tag:blogger.com,1999:blog-86296192572689500912024-03-13T23:51:10.475-03:00One Astronomer's NoiseCebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.comBlogger18125tag:blogger.com,1999:blog-8629619257268950091.post-19745555807000059162024-03-02T18:41:00.002-03:002024-03-02T19:31:27.566-03:00James Webb Discovers that Dwarf Galaxies Have Reionized the Universe<p>Using the unprecedented capabilities of the NASA/ESA/CSA James Webb Space Telescope in <a href="https://explorecosmos.website/" target="_blank">exploring the Universe</a>, an international team of scientists has obtained the first spectroscopic observations of the faintest galaxies during the first billion years of the Universe. These findings help answer a long-standing question for astronomers: what sources caused the reionization of the Universe?</p><p>Much remains to be understood about the timing of the early history of the Universe known as the era of reionization. It was a period of darkness without stars or galaxies, filled with a dense fog of hydrogen gas, until the first stars ionized the gas around them and light began to travel through them. Astronomers have spent decades trying to identify the sources that emitted radiation powerful enough to gradually remove this hydrogen fog that covered the early Universe.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLphyphenhyphensS0q1bVHhuIUFKSk0VCDwKwLHDoIrxxTBqgixCiN7ax93nKAcxJGZvCvMhBBU83Y2YkpvUiomUQGeEnlGJxCNia90Kk1VCHmSQpttgW1rrFzQG0Y0YAiOR6jUqGcMGmzB7eISo6vJuSCiceq4RwQB2EnvZS-gsjfwPPbvO7YlsB-E4ERXNWQns5M/s1140/Dwarf%20Galaxies%20Have%20Reionized%20the%20Universe.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="867" data-original-width="1140" height="486" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjLphyphenhyphensS0q1bVHhuIUFKSk0VCDwKwLHDoIrxxTBqgixCiN7ax93nKAcxJGZvCvMhBBU83Y2YkpvUiomUQGeEnlGJxCNia90Kk1VCHmSQpttgW1rrFzQG0Y0YAiOR6jUqGcMGmzB7eISo6vJuSCiceq4RwQB2EnvZS-gsjfwPPbvO7YlsB-E4ERXNWQns5M/w640-h486/Dwarf%20Galaxies%20Have%20Reionized%20the%20Universe.jpg" width="640" /></a></div><br /><p>The Ultradeep NIRSpec and NIRCam ObserVations before the Epoch of Reionization (UNCOVER) program consists of images and spectroscopic observations of the Abell 2744 lensing cluster. An international team of astronomers used gravitational lenses for this purpose, also known as the Pandora Cluster, to investigate the sources of the Universe's reionization period. Gravitational lenses magnify and distort the appearance of distant galaxies, so they look very different from those in the foreground.</p><p>The 'lens' of the galaxy cluster is so massive that it deforms the structure of space itself, to the point that the light from distant galaxies passing through the deformed space also takes on a deformed appearance. The magnification effect allowed the team to study very distant light sources beyond Abell 2744, revealing eight extremely faint galaxies that would otherwise be undetectable, even for Webb.</p><p>The team found that these faint galaxies are immense producers of ultraviolet light, at levels four times higher than previously assumed. This means that most of the photons that reionized the Universe likely came from these dwarf galaxies.</p><p>"This discovery reveals the crucial role played by ultra-faint galaxies in the evolution of the early Universe," said Iryna Chemerynska, a member of the team from the Institute of Astrophysics of Paris in France. "They produce ionizing photons that transform neutral hydrogen into ionized plasma during cosmic reionization. It highlights the importance of understanding low-mass galaxies in shaping the history of the Universe.</p><p>"These cosmic powerhouses collectively emit more than enough energy to do the work," added team leader Hakim Atek, also from the Institute of Astrophysics of Paris and lead author of the paper describing this result. "Despite their small size, these low-mass galaxies are prolific producers of energetic radiation, and their abundance during this period is so substantial that their collective influence can transform the entire state of the Universe."</p><p>To reach this conclusion, the team first combined data from extremely sensitive Webb images with images of Abell 2744 from the NASA/ESA Hubble Space Telescope to select extremely faint candidate galaxies at the time of reionization.</p><p>This was followed by spectroscopy with Webb's Near-Infrared Spectrograph (NIRSpec). The instrument's multi-shutter array was used to capture multiple spectra of these faint galaxies. This is the first time scientists have reliably estimated how common faint galaxies are. The results confirm that they are the most abundant type of galaxies during the reionization era. This is also the first time that the ionizing power of these galaxies has been measured, allowing astronomers to determine that they are producing enough energetic radiation to ionize the early Universe.</p><p>"The incredible sensitivity of NIRSpec combined with the gravitational amplification provided by Abell 2744 allowed us to identify and study in detail these galaxies from the first billion years of the Universe, despite being more than 100 times fainter than our own Milky Way," said Hakim.</p><p>In an upcoming Webb observation program, called GLIMPSE, scientists will obtain the most sensitive observations ever made in the sky. By targeting another galaxy cluster, called Abell S1063, even fainter galaxies will be identified during the reionization era. This will allow scientists to verify if the dwarf galaxies from the current study are typical of the large-scale galaxy distribution. As these new results are based on observations obtained in one field, the team notes that the ionizing properties of faint galaxies may appear differently if they reside in denser regions.</p><p>Therefore, additional observations in a different field will provide more information and help verify these conclusions. GLIMPSE observations will also help astronomers investigate the period known as cosmic dawn, when the Universe was only a few million years old, to enhance our understanding of the emergence of the first galaxies.</p>MS2http://www.blogger.com/profile/11765803565278277995noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-82150030389480546392022-08-03T16:21:00.004-03:002024-03-02T14:50:37.092-03:00The James Webb Telescope shows amazing images of the Cartwheel Galaxy<p>It is located 500 million light-years from Earth, in the Sculptor constellation. What this stunning photograph reveals about the past and future of this galaxy.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiFO7YA2YgLHcSyfNEwMW767KYk4hTEYq3e09OKwd8Qeuh5RZQtC-XITx-98WL9sdgBBTXsSjSk7rmiFy8M371YROdbCEgK7R23Mma5U5atKIr7h9cSvxIcKxvS60SqTRfgY6ACgrv6w3ToVwTvXLATwNNbHn4jiHx3AlnLAIiVHJkvgJ6VILIqKyhW/s992/webb.webp" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="992" data-original-width="992" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiFO7YA2YgLHcSyfNEwMW767KYk4hTEYq3e09OKwd8Qeuh5RZQtC-XITx-98WL9sdgBBTXsSjSk7rmiFy8M371YROdbCEgK7R23Mma5U5atKIr7h9cSvxIcKxvS60SqTRfgY6ACgrv6w3ToVwTvXLATwNNbHn4jiHx3AlnLAIiVHJkvgJ6VILIqKyhW/w640-h640/webb.webp" width="640" /></a></div><br /><p><i>"This image of Cartwheel and its companion galaxies is a composite from Webb's Near-Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI), revealing details that are difficult to see in the individual images alone," they said. a statement (NASA, ESA, CSA, STScI, Webb ERO production team).</i></p><p>Since it began to generate images, the James Webb Space Telescope has been able to provide a look through time and large amounts of dust. In each photograph, the so-called largest and most powerful telescope ever launched into space managed to amaze the world. It has now released a new image of the Cartwheel Galaxy, also known as the Wagon Wheel Galaxy, located about 500 million light-years from Earth in the Sculptor constellation. What this image revealed, cataloged by experts as “unprecedented”.</p><p>“The Cartwheel Galaxy, located some 500 million light-years away in the Sculptor constellation, is a rare sight. Its appearance, much like that of a cartwheel, is the result of an intense event: a high-speed collision between a large spiral galaxy and a smaller galaxy not seen in this image. and the European Space Agency in a statement.</p><p>In that sense, they highlighted that “collision of galactic proportions cause a cascade of different and smaller events between the galaxies involved; and Cartwheel is no exception", as the image revealed "new details about star formation and the galaxy's central black hole".</p><p>They also noted that this high-speed collision caused Cartwheel to take its current shape, as the impact caused the formation of two rings that spread out from the center of the galaxy "like ripples in a pond after a stone is thrown," they said. . "The collision most notably affected the shape and structure of the Cartwheel Galaxy, which sports two rings: a bright inner ring and a surrounding colorful ring," they described.</p><p>These two rings, they noted, "expand outward from the center of the collision" and, as a result, astronomers called it a "ring galaxy," a less common structure than spiral galaxies like our Milky Way. “The bright core contains a huge amount of hot dust, and the brightest areas are home to gigantic clusters of young stars. On the other hand, the outer ring, which has been expanding for about 440 million years, is dominated by star formation and supernovae,” they continued. "As this ring expands, it collides with surrounding gas and triggers star formation," they noted.</p>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-12512984582803897932018-10-09T23:56:00.005-03:002024-03-02T13:00:46.630-03:00Upcoming astronomical events<div style="text-align: justify;"><b>October</b></div><div style="text-align: justify;"><br />
</div><ul style="text-align: justify;"><li>October 9: New Moon. This phase occurs at 03:47 UTC.</li>
<li>October 21-22: Rain of Orionian stars. The Orionids produce up to 20 meteors per hour at their peak. It is produced by the dust grains left by Halley's comet, which is known and observed since antiquity. It can be observed from October 2 to November 7. This year reaches its peak on the night of October 21-22. The nearly full moon will block some of the weaker meteors this year, but the Orionids tend to be quite bright so it could still be a good show. Meteors will radiate from the Orion constellation, but they can appear anywhere in the sky.</li>
<li>23 de octubre: Urano en oposición. El planeta azul verdoso estará en su punto más cercano a la Tierra y su cara estará completamente iluminada por el Sol. Será más brillante que en cualquier otra época del año y visible durante toda la noche. Este es el mejor momento para ver a Urano. Debido a su distancia, Urano solo aparecerá como un pequeño punto azul verdoso en todos los telescopios, excepto en los más potentes.</li>
<li>24 de octubre: Luna llena. Esta fase ocurre a las 16:46 UTC. Esta luna llena era conocida por las primeras tribus nativas americanas como la Luna de Full Hunters o “luna del cazador”, porque su luz se aprovecha tradicionalmente para la caza.</li>
</ul><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><b>November</b></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMGjiwn9_HIpQ5Xuamw3UK91-FsdV3GcQEd0_lGfbI3aWbn5dvRsvhF0xGstOaxSQxgmCMYzePlPZsg6c7P73rRBs0EkBgfoOtlFudLoy9cGPWr4Dhmg8VMq3CKJ-4NXMI0SBjCm5_uOgUjji1aAO4_h4hpu6GayXVT-ph831GmM19vvHD9w2W7LEGr7k/s640/Rain%20of%20Taurids.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="427" data-original-width="640" height="428" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiMGjiwn9_HIpQ5Xuamw3UK91-FsdV3GcQEd0_lGfbI3aWbn5dvRsvhF0xGstOaxSQxgmCMYzePlPZsg6c7P73rRBs0EkBgfoOtlFudLoy9cGPWr4Dhmg8VMq3CKJ-4NXMI0SBjCm5_uOgUjji1aAO4_h4hpu6GayXVT-ph831GmM19vvHD9w2W7LEGr7k/w640-h428/Rain%20of%20Taurids.jpg" width="640" /></a></div><div style="text-align: justify;"><br /></div><ul style="text-align: justify;"><li>November 5 and 6: Rain of Taurids. The Taurids are a small meteor shower of long duration that produce only 5-10 meteors per hour. It is born from two separate flows. The first is produced by the dust grains left by Asteroid 2004 TG10. The second sequence is produced by debris left by Comet 2P Encke. The Tauride rain takes place from September 7 to December 10. This year reaches its peak on the night of November 5. The thin crescent moon will leave the skies dark for good observation, especially just after midnight. The meteors will radiate from the constellation of Taurus, but they can appear in any part of the sky.</li>
<li>November 6: The planet Mercury reaches the highest eastern elongation of 23.3 degrees from the Sun. This is the best time to see Mercury, since it will be at its highest point on the horizon in the night sky.</li>
<li>November 7: New Moon. This phase occurs at 16:02 UTC.</li>
<li>November 17 and 18: Leonid meteor shower. The Leonids are a shower of average stars, producing up to 15 meteors per hour at their peak. This rain is unique since it has a cyclonic peak every 33 years, in which hundreds of meteors per hour can be seen. The last of these peaks occurred in 2001. The Leonids are produced by the dust grains left by Comet Tempel-Tuttle, which was discovered in 1865. The rain can be observed from November 6 to 30 and the best day will be from 17 to November 18th. The sky will be quite dark for what could be a good show at dawn. The meteors will radiate from the constellation of Leo, but they can appear in any part of the sky.</li>
<li>November 23: Full moon. This phase occurs at 05:40 UTC. This full moon was known by the first Native American tribes as Full Beaver Moon or "beaver moon", as it is the time of year to place beaver traps before the swamps and rivers freeze.</li>
</ul>
<div style="text-align: justify;"><b>December</b></div><div style="text-align: justify;"><br />
</div><ul style="text-align: justify;"><li>December 7: New Moon. This phase occurs at 07:20 UTC. This is the best time of the month to observe weak objects such as galaxies and star clusters because there is no moonlight to interfere.</li>
<li>December 13 and 14: Rain of Geminid meteorites. The Geminids are the queens of meteor showers. It is considered by many to be the best shower of stars, producing up to 120 multicolored meteors per hour at its peak. It is produced by remains left by an asteroid known as 3200 Phaethon, which was discovered in 1982. This rain occurs annually from December 7 to 17. Its moment of apogee this year will be on the night of December 13 to 14. The Moon will not be a problem. Meteors will radiate from the constellation of Gemini, but they can appear anywhere in the sky.</li>
<li>December 15: The planet Mercury reaches the highest western elongation of 21.3 degrees from the Sun. This is the best time to see Mercury, since it will be at its highest point on the horizon in the morning sky.</li>
<li>December 21: December solstice. The December solstice occurs at 22:23 UTC. The South Pole of the Earth will be inclined towards the Sun, which will have reached its southernmost position in the sky and will be directly above the Tropic of Capricorn at 23.44 degrees south latitude. This is the first day of winter (winter solstice) in the northern hemisphere and the first day of summer (summer solstice) in the southern hemisphere.</li>
<li>December 22: Full moon. This phase occurs at 17:49 UTC. This full moon was known by the first Native American tribes as the Cold Full Moon because this is the time of year when the cold winter air settles and the nights become long and dark.</li>
<li>December 21 and 22: Rain of Ursid stars. The Ursidas are a small meteor shower that produces between 5 and 10 meteors per hour. It is produced by dust grains left by Comet Tuttle, which was discovered for the first time in 1790. The rain takes place from December 17 to 25, with its peak this year on the night of December 21-22. This year, the glow of the full moon will hide all the brightest meteors. The meteors will radiate from the constellation Ursa Minor, but they can appear anywhere in the sky.</li>
</ul>
Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-8248094853631453172018-09-21T21:46:00.004-03:002024-03-02T14:38:41.426-03:00They detect a strange disturbance in the Milky Way<div style="text-align: justify;">The Gaia space probe, the European mission that aims to develop a detailed catalog with the position, distance and speed of more than a billion stars in our galaxy, has just found a surprising "disturbance" in the Milky Way. And it is that the galaxy in which we live is, still, suffering the effects of a past "encounter". In fact, millions of stars do not follow the "sweet and flat" orbit around the galactic center, as would be expected, but move in a similar way to water waves in a pond after throwing a stone. The surprising find is published this week in Nature.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiB-9kwXrcYVb8B-ndkLYkzEYIYKcLMnQqe1wj6XFPE2XAHKLlvW1FrcUmJWOknHN5zLizzcroy639Xcqi8r7ZcdPdESlaGGiU3VqbyzHdCxfpeUGaBNSmORfMYTvquJ0NVulq0TbPwlGNPksSnD_45ugFiyFagAUCrYue-x2230RQJV9o6fmHCBikQ_3I/s1600/Gaia%20space%20probe.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1199" data-original-width="1600" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiB-9kwXrcYVb8B-ndkLYkzEYIYKcLMnQqe1wj6XFPE2XAHKLlvW1FrcUmJWOknHN5zLizzcroy639Xcqi8r7ZcdPdESlaGGiU3VqbyzHdCxfpeUGaBNSmORfMYTvquJ0NVulq0TbPwlGNPksSnD_45ugFiyFagAUCrYue-x2230RQJV9o6fmHCBikQ_3I/w640-h480/Gaia%20space%20probe.jpg" width="640" /></a></div><div style="text-align: justify;"><br /></div>According to the researchers, the encounter with another galaxy took place sometime in the last between 300 and 900 million years. And that encounter was discovered, precisely, thanks to the pattern of movement of the stars in the disk of the Milky Way.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">"We made a graph of the z-coordinate (the height of the stars above or below the disk of the galaxy) versus the velocity Vz (velocity with which the stars move in the vertical direction on the disk) and, surprisingly, what appeared was a perfect spiral, similar to the shell of a snail, "the study's lead author, Teresa Antoja, a researcher at the Institute of Cosmos Sciences at the University of Barcelona (ICCUB), told the Sinc agency.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">"So perfect it seemed to us the way we saw in the graphics of the computer - adds the researcher - that we thought that we could have been wrong in something, or that there would be some problem in the data. But after multiple checks and knowing that the Gaia data has gone through an exhaustive quality control, we came to the conclusion that this spiral was something real ".</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The helical shape detected by the researchers means that the stars are not moving, as would be expected in an equilibrium galaxy, in simple circles around the center of the Milky Way, but rather follow more complex patterns.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">These patterns were revealed because Gaia not only accurately measures the positions of more than a billion stars, but also their speeds in the plane of the sky. And for this subset of a few million stars, Gaia provided an estimate of the full three-dimensional velocities, which allowed a study of stellar motion using the combination of position and velocity.</div>
<h2 style="text-align: justify;">«I was shocked»</h2><div style="text-align: justify;">When Teresa Antoja first observed the patterns on her computer screen, she could not believe what she was seeing. One form in particular strongly attracted his attention. It was a spiral pattern, similar to a snail, that emerged in the graph that traced the altitude of the stars above or below the plane of the Galaxy. Never before had seen anything like it.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">"At the beginning - explains Antoja - the characteristics were very strange for us, I was shocked and I thought there could be a problem with the data". But the Gaia data had been subjected to multiple validation tests before launch. In addition, together with her collaborators, Teresa Antoja carried out multiple tests to look for errors that could explain the observed forms. When not detecting any error, the conclusion was that everything they were seeing was really happening.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The reason why the phenomenon had not been previously detected is simple: never before had the scientists had in their hands an instrument with the power and capacity of Gaia. "It's as if suddenly you put on the right glasses and you could see all the things you could not see before," says the researcher.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Once confirmed that the structures that reflected the data were real, it was time to find out what had caused them and why they were there. "It's like throwing a stone in a pond, and see how the water moves in waves and waves," says Antoja.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">However, unlike water molecules, which end up settling down and recovering their original shape, the stars are able to retain a "memory" of what disturbed them. And that memory is precisely in their movements. With the passage of time, and although the waves are no longer easy to see in the distribution of the stars, it is still possible to locate them when studying their velocities.</div>
<h2 style="text-align: justify;">Cannibal galaxy</h2><div style="text-align: justify;">The next question was to find out what it was that had hit the Milky Way for the stars to behave that way. From other research, we know that our galaxy is a "cannibal", which has been growing by "devouring" other smaller galaxies throughout its history. But that does not seem to be the case on this occasion.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Amina Helmi, from the Dutch University of Groningen and co-author of the study, had already done other work on a small galaxy, Sagittarius, which barely contains some tens of millions of stars and which is currently being cannibalized by the Milky Way. And it turns out that his most recent approach to our galaxy was not a direct hit, but it happened very close to it, almost touching it. Something more than enough for its gravity to disturb some millions of stars in the Milky Way, just as a stone thrown into a pond would disturb the water.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">In addition, it is the case that this last close encounter of Sagittarius with the Milky Way occurred sometime between 200 and 1,000 million years ago, a time that coincides almost perfectly with the one that Teresa Antoja calculated for the origin of the spiral shape of the movement of the stars observed by Gaia.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Now, researchers want to study this galactic encounter in much more detail. "The discovery was easy," Amina Helmi says, "the interpretations are more difficult, and a full understanding of their meaning and implications could take several years."</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The Milky Way, of course, has a very rich story to tell. And we are just beginning to read it.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-83009657496159734232018-09-14T09:27:00.001-03:002024-03-02T14:37:46.801-03:00Uranus smells rotten<div style="text-align: justify;">Although we already knew that Uranus is probably one of the most hostile places for life in the Solar System, now we have one more reason not to travel to this planet: its smell. And is that a team of scientists has just shown that in the upper layers of the atmosphere of Uranium abounds hydrogen sulfide, a gas responsible for the classic smell of rotten eggs.</div><div style="text-align: justify;"><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://4.bp.blogspot.com/-X2Di17Gvaxw/W5unzblUOVI/AAAAAAAAACc/D3k_zydRtQoWMMfhfJAFtAVsZQyvSq7IwCLcBGAs/s1600/uranus.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="570" data-original-width="760" height="480" src="https://4.bp.blogspot.com/-X2Di17Gvaxw/W5unzblUOVI/AAAAAAAAACc/D3k_zydRtQoWMMfhfJAFtAVsZQyvSq7IwCLcBGAs/w640-h480/uranus.jpg" width="640" /></a></div></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The researchers, who publish their work in the journal Nature Astronomy, have discovered that this noxious gas swirls in the clouds of the giant planet. Although it was something that was suspected, nobody until now had been able to demonstrate the composition of these clusters.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Why is it so difficult to study the composition of Uranus clouds? According to Leigh Fletcher, of the University of Leicester, when a layer of clouds is formed by condensation, the forming gas is trapped in an internal deposit at such low levels that it is very difficult to detect it by most of the instruments used up to now. "Only a small amount remains above the clouds in the form of saturated steam," explains the scientist.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The discovery was possible thanks to the Gemini North telescope, located in Mauna Kea (Hawaii), with which the researchers were able to capture the Sun's light by reflecting on the upper layer of the Uranian clouds and analyzing it by spectrometry. "Thanks to the improved data from the hydrogen sulfide absorption line and the wonderful Gemini spectra, we have the fingerprint we needed to 'catch' the culprit," explains Patrick Irwin, a researcher at the University of Oxford and lead author of the study. "The lines we tried to detect were very weak, but due to the high sensitivity of the Gemini spectrometer and the good weather conditions at Mauna Kea we were able to detect them unequivocally."</div>
<h2 style="text-align: justify;">Exploring the history of our Solar System</h2><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The work highlights the differences between the so-called "gaseous giants" (Jupiter and Saturn) and the "ice giants" (Uranus and Neptune). While in the former it is ammonia that is detected in the clouds, in Uranus, and possibly in Neptune as well, hydrogen sulfide is the main component. According to Leigh, these differences would have originated from the moment of the birth of the planets. "During the formation of the Solar System, the balance between nitrogen and sulfur - and therefore between ammonia and hydrogen sulfide - was determined by the temperature and location of each planet."</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">These findings reveal that, although Uranus' atmosphere is a tremendously unpleasant place for humans, this vast world is a fertile ground for exploring the history of our Solar System and perhaps also for understanding the conditions that exist in other large icy planets that orbit stars beyond our Sun.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">With its discovery, the team of researchers has also found a new application for the large telescope. "This work is a new and innovative use for an instrument originally designed to analyze the explosive environments around black holes located in the center of distant galaxies," explains Chris Davis, of the National Science Foundation (USA) , one of the funders of the Gemini telescope. "Using it to solve a mystery in our Solar System is a new application with a lot of potential for future research."</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-38891467796048048902018-08-18T19:07:00.001-03:002024-03-02T14:40:15.726-03:00Astronomers discover a 'super Saturn'<div style="text-align: justify;">A team of astronomers from the Leiden Observatory (The Netherlands) and the University of Rochester (USA) has discovered a ring system close to a star similar to the Sun, named 'J1407'. The finding has been published in the journal Astrophysical Journal.</div><div style="text-align: justify;"><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://2.bp.blogspot.com/-tFEEP7WacNM/W2jG3hmSsJI/AAAAAAAAACQ/zcF_nkNji4ME12NAKqh_P9iLrxlo4MrRACLcBGAs/s1600/super-saturn.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="570" data-original-width="760" height="480" src="https://2.bp.blogspot.com/-tFEEP7WacNM/W2jG3hmSsJI/AAAAAAAAACQ/zcF_nkNji4ME12NAKqh_P9iLrxlo4MrRACLcBGAs/w640-h480/super-saturn.jpg" width="640" /></a></div></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The planet in question was discovered a few years ago by the University of Rochester. Then, it was learned that this seemed to have a considerable size and was surrounded by a ring system, being the first of its kind found outside the Solar system. Now, thanks to the new observations, scientists have discovered that these rings are gigantic: not only are they huge but they count 30 rings and occupy 120 million kilometers (200 times more than those of Saturn). This size would mean that if Saturn had this kind of rings, they would be visible to the naked eye from Earth as we see the Moon every day in the sky, or even better.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Astronomers found these objects when they eclipsed the star, a phenomenon that lasted several weeks and allowed experts to appreciate details such as the fineness of the rings. "The star is too far away for the rings to be seen directly, but a detailed model could be made based on the variations in the light brightness of the star passing through the ring system," explains Matthew Kenworthy, leader of the study.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">"You could think of it as a kind of super-Saturn. In particular, each ring measures tens of millions of kilometers in diameter. If the four large Galilean satellites of Jupiter were ground into dust and ice and the material spread out in their orbits in a ring around Jupiter, the ring would be so opaque to light that a distant observer would see the ring passing in front of the Sun. I would see a deep eclipse, "explains Eric Mamajek, co-author of the study.</div>
<div style="text-align: justify;">According to experts' estimates, this colossal ring system is likely to contain more or less the mass of an Earth in the dust particles that obscure the light and that the planet has an orbital period of more or less a decade of duration.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-20289003943272268602018-08-12T19:01:00.001-03:002024-03-02T14:41:17.102-03:00 Scientists discover a 'young Jupiter'<div style="text-align: justify;">A team of astronomers led by Bruce Macintosh of the University of Standford (USA) has discovered thanks to the Gemini Planet Imager (GPI) instrument, a cutting-edge camera to capture planets, a planet very similar to Jupiter, a "young Jupiter "that weighs twice as much as this one but much less than the exoplanets observed so far directly. Its mass is approximately five times more than Jupiter.</div><div style="text-align: justify;"><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-j_bu1tDfXys/W2jGEdDMrDI/AAAAAAAAACI/i7W3X4gQ9LEy0Thz7cCHBBY8hA5d8vG7wCLcBGAs/s1600/eridani.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="570" data-original-width="760" height="480" src="https://1.bp.blogspot.com/-j_bu1tDfXys/W2jGEdDMrDI/AAAAAAAAACI/i7W3X4gQ9LEy0Thz7cCHBBY8hA5d8vG7wCLcBGAs/w640-h480/eridani.jpg" width="640" /></a></div></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">"To detect exoplanets, other telescopes such as Kepler from NASA see its shadow; however, GPI sees its brightness, which is what we refer to as a direct image, "explains Macintosh.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">His name is 51 Eridani b and orbits around the 51st Eridani star just 13 astronomical units away from its star, which is about 20 million years old.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Thanks to Gemini Planet Imager and its ability to detect objects that have a density much lower than any of those already discovered, it is possible to locate young planets like this one that still retain the heat derived from their formation stage. Thus, in examining thermal emissions, scientists have discovered that methane is the main component of its atmosphere, as in Jupiter.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">In the study they also explain that this exoplanet formed in a similar way to the process that Jupiter experienced in its evolution. The finding has been published in the journal Science.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-76576396682306997992018-08-06T18:58:00.003-03:002024-03-02T14:43:21.322-03:00 Jupiter would have ejected a giant planet from the solar system<div style="text-align: justify;">As if it were a cosmic chess game, a team of astrophysicists from the University of Toronto (USA) has discovered that a close encounter with the planet Jupiter about 4,000 million years ago could have led to the expulsion of another giant planet (the fifth) of our solar system. The study has been published in the journal The Astrophysical Journal.</div><div style="text-align: justify;"><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://4.bp.blogspot.com/-sjCCjs-I0KM/W2jEW45oGTI/AAAAAAAAAB8/IvVS64MOul4AuE_JNG7g7Y7piknoQXWTQCLcBGAs/s1600/jupiter.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="570" data-original-width="760" height="480" src="https://4.bp.blogspot.com/-sjCCjs-I0KM/W2jEW45oGTI/AAAAAAAAAB8/IvVS64MOul4AuE_JNG7g7Y7piknoQXWTQCLcBGAs/w640-h480/jupiter.jpg" width="640" /></a></div></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">For years scientists have theorized about the existence of this fifth giant planet next to Jupiter, Saturn, Uranus and Neptune, which could have been expelled by Saturn or by Jupiter as a result of a planetary encounter in which one of them is freed from the gravitational attraction of its star. Now, new evidence suggests that Jupiter was responsible for this event.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">To reach this conclusion, the astrophysicists studied the moons of these two gaseous giants as well as their moons generating computer simulations based on the current trajectories of Callisto and Iapetus, satellites in regular orbit around Jupiter and Saturn, respectively. Once the simulations were developed, they proceeded to measure the probabilities that Callisto and Iapetus would have generated their current orbit if their host planets had expelled that hypothetical fifth planet from the solar system, since this event would have considerably modified its original orbi</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The results revealed that "Jupiter was able to eject the fifth giant planet, keeping a moon with Callisto's orbit. On the other hand, it would have been very difficult for Saturn to do it because Iapetus would have been excessively unstable, because of the result of an orbit that is difficult to reconcile with its current trajectory, "explains Ryan Cloutier, lead author of the study.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-75661218056336320762018-07-23T16:13:00.001-03:002024-03-02T14:50:24.707-03:00The threat that comes from space<div style="text-align: justify;">Although we have always thought that if there was danger that something would fall on our heads would be asteroids, a team of astronomers from the University of Buckingham and Armagh Observatory have warned that the real danger comes from a few peculiar objects located in the outer Solar System and that have been observed during the last two decades.</div><div style="text-align: justify;"><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://3.bp.blogspot.com/-b-scW9OScvM/W1YfusvM42I/AAAAAAAAABk/jN1WBSvWyXcqwqY2mYZ7NuapTjjCaI4LwCLcBGAs/s1600/space.jpg" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="570" data-original-width="760" height="480" src="https://3.bp.blogspot.com/-b-scW9OScvM/W1YfusvM42I/AAAAAAAAABk/jN1WBSvWyXcqwqY2mYZ7NuapTjjCaI4LwCLcBGAs/w640-h480/space.jpg" width="640" /></a></div></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">These giant objects are called Centaurs, since they seem to be a mixture of asteroids and comets (like the mythological Centaur half man, half horse), move in unstable trajectories while crossing the orbits of Jupiter, Saturn, Uranus and Neptune. Obviously, the gravitational pulls to which they are subjected by these gaseous giants cause their orbits to be altered and that, from time to time, they enforce the path to Earth.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The Centaurs have a typical size of 50 to 100 km and a single body has more mass than the set of all the asteroids that cross the Earth's orbit discovered to date. According to the calculations made by this team of astronomers, one of these Centaurs goes towards the Earth once every 40,000-100,000 years, although the problem is not that it is going to hit us; It is something much worse. When it is close to the Sun it disintegrates, creating a cloud of dust and solid debris and flooding the inner Solar System with debris that makes the impact of some of them with our planet inevitable.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-67388465678772958412018-07-15T16:35:00.005-03:002024-03-02T14:53:24.976-03:00 Enceladus and Europe gather several of the ingredients necessary for life<div style="text-align: justify;">NASA is focusing its efforts on seeking extraterrestrial life in the Solar System and beyond. And life, as we understand it, depends on three main factors: liquid water, a source of energy for metabolism and the right chemical ingredients, mainly carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. In the Solar System there are two possible ocean worlds that meet some of these requirements, necessary for a place to be habitable. Enceladus and Europa, two satellites of Saturn and Jupiter respectively, are the most reliable candidates, as revealed by NASA today. "We have never been so close to detecting a place with some of the ingredients necessary for an environment to be habitable," says Thomas Zurbuchen, a NASA astrophysicist.</div><div style="text-align: justify;"><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqqYPqVLl2PjjhVX8dI2-VCBCBLcRdjeK-UtHMqa-ygWVUiuSLaRbcf8vSyq1JZa1_80COX5axnK_5v4uAqrKNKd1tk2v0MoiCS3u7edypAtNyg-YM_T2iNHWQBOAeE4AU3rHhtcuw8SimIcRIBzFs5F-JKw9QzJgokafgLJ_2IlaM5dy4zxEMMBkXKS4/s2160/Enceladus%20and%20Europe.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1080" data-original-width="2160" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqqYPqVLl2PjjhVX8dI2-VCBCBLcRdjeK-UtHMqa-ygWVUiuSLaRbcf8vSyq1JZa1_80COX5axnK_5v4uAqrKNKd1tk2v0MoiCS3u7edypAtNyg-YM_T2iNHWQBOAeE4AU3rHhtcuw8SimIcRIBzFs5F-JKw9QzJgokafgLJ_2IlaM5dy4zxEMMBkXKS4/w640-h320/Enceladus%20and%20Europe.jpg" width="640" /></a></div><br /><div style="text-align: justify;">Hydrogen gas, which could potentially provide a source of chemical energy for life, is distributed by the ocean that would be in the underground of Enceladus thanks to the hydrothermal activity of the seabed. If there were microbes then they could use hydrogen for energy by combining hydrogen with carbon dioxide dissolved in water. This chemical reaction called methanogenesis, because it produces methane as a byproduct, is at the roots of earthly life and could be crucial to the origin of life on Earth. The Cassini spacecraft has shown that Enceladus has almost all the necessary ingredients to be habitable; Phosphorus and sulfur have not yet been detected in the ocean, but scientists suspect that they might exist, since the rocky core of Enceladus appears to be chemically similar to meteorites that contain both elements.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">On the other hand, some images taken by the Hubble Space Telescope indicate that the water vapor columns of Europe could be a real phenomenon, sprouting intermittently in the same region of the lunar surface. A new image shows a column that rises about 100 kilometers above the surface of Europe. Researchers believe that, as with Enceladus, this could be evidence that water is being expelled from inside the moon.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-76364032996794092982018-07-08T05:34:00.002-03:002024-03-02T15:04:49.909-03:00 5 applications for astronomy students<div style="text-align: justify;">A selection of the best applications for astronomy students that you can download for free on your iPad or iPhone.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">If you ever used to look for astronomy applications you will know that the vast majority are paid, with a price range ranging from 3 to 30 euros. Without giving up on offering the best applications for students of astronomy with free download, we achieved a short list but that gathers the highest astronomical references passing through NASA, the stars, the planets or the lunar phases. What are you waiting for to turn your Smartphone into a guided telescope?</div><div style="text-align: justify;"><br />
</div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjE6eKBt51A8cfmaT7_NlK-AyM3HEClhgbQTImXdM8XymWfTae4YYmzpcNUhorqAmpSDCmmLpQ7ttUXdLgTkIRzP7MB7zgsQ6_-ubvScGoHnT7OdIj2mlW1qDPEoIia9f-hn6yCVM-zFW_REX8BBMlrEPoQ-lPhJzXzgxxhqcSeK31WvVSau2xYZh2xCKA/s512/Star%20Chart.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="512" data-original-width="512" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjE6eKBt51A8cfmaT7_NlK-AyM3HEClhgbQTImXdM8XymWfTae4YYmzpcNUhorqAmpSDCmmLpQ7ttUXdLgTkIRzP7MB7zgsQ6_-ubvScGoHnT7OdIj2mlW1qDPEoIia9f-hn6yCVM-zFW_REX8BBMlrEPoQ-lPhJzXzgxxhqcSeK31WvVSau2xYZh2xCKA/w400-h400/Star%20Chart.png" width="400" /></a></div><br /><div style="text-align: justify;"><br /></div><div style="text-align: justify;"><b>1. Star Chart</b></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">It uses GPS technology to calculate in real time what the location of a star or planet is even when the sun shines. Find out the name of your favorite star pointing towards it with the camera of your iPhone, transforming it into a virtual telescope that allows you to see a 3D universe. The Star Chart works like a plane of the night sky implemented by the astronomers to identify stars, constellations or galaxies, facilitating the realization of distance calculations or probabilities of phenomena.</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPDmJSygwZ1vFYsvrvIhWUO6eF2oDxAvQg_6KVOT7-sQY8RX3xFCV4u6hsooOvdkRwALzBwd9fzRadXlCx73VTT4HGg9HGKCX8jQCynW615zi_X8Wr362YGyhXYy5gjhbEXw2N9H7MXL1GX3vfyf_m9l8nQWWC76ZgeHsqRAnsmNdqe5atdtf7pftVmOY/s246/nasa.webp" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="246" data-original-width="246" height="400" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjPDmJSygwZ1vFYsvrvIhWUO6eF2oDxAvQg_6KVOT7-sQY8RX3xFCV4u6hsooOvdkRwALzBwd9fzRadXlCx73VTT4HGg9HGKCX8jQCynW615zi_X8Wr362YGyhXYy5gjhbEXw2N9H7MXL1GX3vfyf_m9l8nQWWC76ZgeHsqRAnsmNdqe5atdtf7pftVmOY/w400-h400/nasa.webp" width="400" /></a></div><div style="text-align: justify;"><br /></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;"><b>2. NASA</b></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">The official NASA app in its original language to watch its TV broadcasts, videos, its latest releases and even the viewing of its satellite trackers. You can choose between your favorite missions to get direct access to them, receiving the latest information. Send notifications of your tweets as well as upcoming important sightings with the geographic location so you do not miss them. Undoubtedly, an essential app for every student of astronomy or a fan of the mysteries of the universe.</div><div style="text-align: justify;"><br />
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</div><div style="text-align: justify;"><b>3. Night Sky</b></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Astronomical observation that guides you in the search for a constellation or a space station, adding animated models in 3D and the possibility of reducing the irradiation of light to avoid eye damage. The digital crown allows you to travel through time in the celestial vault to enjoy the most important astronomical events in history. You will receive automatic notifications for the departure and start of all the planets, according to your geolocation. It is also possible to select elements to add personalized reminders corresponding to astronomical phenomena.</div>
<div style="text-align: justify;"><b>4. Lunar Phase</b></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Know the position of the moon at all times expressed in latitude and longitude, its age, the exact hours at which each phase begins and how much time is left for sunrise or sunset according to your geolocation. You can find out what happened to the moon the day before or what will happen in the next few days according to astrological predictions. The interface is simple to use so that all the necessary information is on your screen, with simple navigation guided by large options buttons.</div><div style="text-align: justify;"><br />
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</div><div style="text-align: justify;"><b>5. Star Walk + Star Atlas</b></div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">Explore models of celestial bodies in 3D as they were interpreted in ancient times up to the present, receive information about lunar phases, planetary movements or positioning of satellites. You will access thousands of scientific articles for curious space, explaining the biggest unknowns of the great vault. Pointing with the iPhone camera towards a star, you can discover its name or determine if it really is a planet. The night mode protects your eyesight with soft red tones that will make a difference when you are away from the city.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-32374707623583653012018-06-27T22:29:00.002-03:002024-03-02T18:59:08.724-03:00 The worst storm on Mars already covers the entire planet<div style="text-align: justify;">It's getting worse. The spectacular dust storm that has plunged a large part of Mars into darkness in the last two weeks has grown in size and is now officially "global". The phenomenon caused NASA's historic rover Opportunity to suspend its scientific operations, but another explorer robot arrived in 2012, Curiosity, which is currently studying the soil of a place known as Gale Crater, will not be affected by dust. The reason is that although your old companion can not work without sunlight-which is not received by the storm, the most modern has a battery of nuclear energy that works day and night. He has even been able to take a selfie in the storm.</div><div style="text-align: justify;"><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgykxzyDacMRdMQUSodp-IbxrEX7CbosslbTHotaZB14eTRLerPnAFQNdUg8CDtogXAnEdfWWgBOgT20xmW-B-A3GVqMitgFQHN_dyJu2FZXBK0t65QN33Qao06TIG2MO8Vg3Q43Zci4zjCfpKSOcEnEX4xDYVJ9uCmkmxkyrk6TtF_Jvkc2OZUH21bnrI/s1050/Martian%20dust%20storms.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="788" data-original-width="1050" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgykxzyDacMRdMQUSodp-IbxrEX7CbosslbTHotaZB14eTRLerPnAFQNdUg8CDtogXAnEdfWWgBOgT20xmW-B-A3GVqMitgFQHN_dyJu2FZXBK0t65QN33Qao06TIG2MO8Vg3Q43Zci4zjCfpKSOcEnEX4xDYVJ9uCmkmxkyrk6TtF_Jvkc2OZUH21bnrI/w640-h480/Martian%20dust%20storms.jpg" width="640" /></a></div><div style="text-align: justify;"><br /></div>
<div style="text-align: justify;">Although Curiosity is on the other side of the planet with respect to Opportunity, which transits through the Valley of Perseverance, the dust has steadily increased over it, more than doubled over the weekend. The "tau", the index that measures the opacity of the haze, is now above 8.0 in the Gale crater, the highest that the mission has recorded. The last time it was measured on Opportunity was close to 11, enough so that the oldest active rover on Mars (it has been on the Red Planet for fifteen years) can not make precise measurements. If you consider that a storm that Opportunity barely survived in 2007 reached a tau of 5.5, things do not look very good for the veteran.</div><div style="text-align: justify;"><br /></div>
<div style="text-align: justify;">But NASA scientists also see the positive side of things. As they explain, Curiosity offers an unprecedented possibility to answer some questions. Why do some Martian dust storms last for months and become massive, while others remain small and last only a week? "We have no idea," says Scott D. Guzewich, an atmospheric scientist at NASA's Goddard Space Flight Center in Greenbelt, Md., Who leads Curiosity's dust storm investigation.</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-31878683360149370882018-06-19T13:47:00.003-03:002024-03-02T18:29:02.846-03:00Mars declares war<div class="separator" style="clear: both; text-align: center;"><a href="https://3.bp.blogspot.com/-dJrr-O1ngn4/WykzXtBai8I/AAAAAAAAABU/8LpOBcjdrPYKdV-UsKYHvVX1KioAG3ilACLcBGAs/s1600/you-realize-of-course-this-means-war.jpg" style="margin-left: 1em; margin-right: 1em;"><img alt="This means war !!" border="0" data-original-height="1000" data-original-width="1000" height="400" src="https://3.bp.blogspot.com/-dJrr-O1ngn4/WykzXtBai8I/AAAAAAAAABU/8LpOBcjdrPYKdV-UsKYHvVX1KioAG3ilACLcBGAs/s400/you-realize-of-course-this-means-war.jpg" title="This means war !!" width="400" /></a></div>
Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-16939232518590175182009-02-22T14:04:00.002-02:002024-03-02T19:19:36.048-03:00Stellar Images<p>In a remarkable display of celestial beauty, the Hubble Space Telescope has recently captured a stunning new image of the Crab Nebula (M1), one of the most iconic and well-studied remnants of a supernova explosion. This captivating image, released by NASA and the European Space Agency (ESA), showcases the intricate and dynamic structure of the nebula, offering astronomers a deeper understanding of the processes at play within this cosmic wonder.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgIncWPelRo1Di1HjSkkyzC_3Ll_nYAbfuhPm45lavAjEbEyaXh3hvRPT9Erre4q_FpkdbSPcc6laXB9mEgAG3MR6pJ0W9vZA3MGJGmnYvOk1BpBxJ61kuweCsrHse0fA6lW5Du21yBZB1h-HcK90jE0g37piUELNf_lGxIt42ZQ4LR3e0VIFwacUNgppA/s419/Crab%20Nebula%20(M1)%20Supernova.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="236" data-original-width="419" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgIncWPelRo1Di1HjSkkyzC_3Ll_nYAbfuhPm45lavAjEbEyaXh3hvRPT9Erre4q_FpkdbSPcc6laXB9mEgAG3MR6pJ0W9vZA3MGJGmnYvOk1BpBxJ61kuweCsrHse0fA6lW5Du21yBZB1h-HcK90jE0g37piUELNf_lGxIt42ZQ4LR3e0VIFwacUNgppA/w640-h360/Crab%20Nebula%20(M1)%20Supernova.jpg" width="640" /></a></div><br /><p>The Crab Nebula, located approximately 6,500 light-years away in the constellation Taurus, is the result of a supernova explosion observed by Chinese astronomers in the year 1054. This event, which was visible during the day for several weeks, left behind a rapidly expanding cloud of gas and dust, now known as the Crab Nebula. The nebula's intricate structure is a testament to the complex interplay of stellar winds, magnetic fields, and high-energy particles that characterize the aftermath of a supernova.</p><p>The new image, captured by Hubble's Wide Field Camera 3, reveals the nebula's intricate filamentary structure in unprecedented detail. The image showcases the nebula's inner regions, where the rapidly spinning neutron star, or pulsar, at the heart of the nebula resides. The pulsar, which is the collapsed core of the original star, emits beams of radiation that sweep across the surrounding nebula, creating the intricate web of filaments seen in the image.</p><p>This new image of the Crab Nebula not only serves as a stunning visual representation of the beauty of the cosmos but also provides astronomers with valuable insights into the processes that shape the evolution of supernova remnants. By studying the Crab Nebula in various wavelengths of light, astronomers can gain a deeper understanding of the physical processes at play within this dynamic and ever-changing cosmic environment.</p>MS2http://www.blogger.com/profile/11765803565278277995noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-84556467676957578342008-12-11T00:30:00.003-02:002024-03-02T16:24:32.284-03:00Seeing Extrasolar Planets, Part I: Fomalhaut b<p> A little while ago the first images of exoplanets were released and caused quite a stir in the astronomical community, as well as on the <a href="https://gugnico.blogspot.com/2008/11/carnival-of-space-79.html">blogosphere</a>! Here at UVa, like good little grad students, we read and discussed the discovery papers shortly after they were released. I read the papers and took notes of our discussion and just wanted to share some highlights of those to go beyond the press releases.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfYWE47b6lIkt6BSW-EQfknnve7PuU4jkISElaSe6a5tb9xQZmHfKbRxxWjnAEBznwlIgft_ZOB1EDURzAb7vwcveqAcdci6IVu_wpbN6W89Ofb6F2hHqzR0sTqkuvEHLHBehhMTW7DYok2EWWPljqQSgXD7dmcvkdIQmbDpa_NEKSMOJn0J6CD46Dx2E/s1280/Fomalhaut%20b.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="855" data-original-width="1280" height="428" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfYWE47b6lIkt6BSW-EQfknnve7PuU4jkISElaSe6a5tb9xQZmHfKbRxxWjnAEBznwlIgft_ZOB1EDURzAb7vwcveqAcdci6IVu_wpbN6W89Ofb6F2hHqzR0sTqkuvEHLHBehhMTW7DYok2EWWPljqQSgXD7dmcvkdIQmbDpa_NEKSMOJn0J6CD46Dx2E/w640-h428/Fomalhaut%20b.jpg" width="640" /></a></div><br /><p>First, Kalas et al. (astro-ph and Science) present optical images from the Hubble of the star Fomalhaut and its planetary companion, cleverly named Fomalhaut b. From the initial press release, a few of us couldn’t help but think, are you sure that’s a planet in those two images and not some artifact of the imaging? Sure enough the paper lists all six epochs of data in which the planet is imaged. Some are in 2004, others are in 2006, and this allows us to see the motion of the planet in its orbit. The change in position is much larger than the errors, showing it to be a real movement in an orbit! Not only that, but Fomalhaut is moving with respect to us, and this proper motion across the sky can be measured. If the speck of light is really a planet orbiting the star, then its proper motion must be the same. It must be moving along with the star. These observations show that, indeed, it is!</p><p>It had previously been hypothesized that a planet must exist in that region for the debris disk around the star to have the particular shape that it has. The planet’s gravity affects the dusty disk such that it has a sharp inner edge, and the center of the disk is 15 AU away from the star! Given these characteristics of the debris disk and the actual observations of the planet’s location, models show that it is probably around 3 times the mass of Jupiter. The models quite definitively rule out very massive objects, close to brown dwarf masses. What we have here is definitely a planet.</p><p>Two points are not enough to constrain the orbital parameters of this planet, especially when the orbit’s inclination, or tilt with respect to us, is not well known. However, the planet is approximately 115 AU away from the star. Remember, 1 AU defines one “astronomical unit” or the mean distance between the Earth and the Sun (roughly some 93 million miles.) The furthest planet in our solar system, Neptune, orbits at an average of 30 AU from the Sun. The Kuiper Belt, populated with icy bodies such as Pluto, is at roughly 50 AU from the Sun. Fomalhaut b orbits at more than double that! This is reminder that planetary system formation scenarios must take in a wide range of solar systems as end products from their models. For decades, we only had a sample size of one, our dear Sol and its puny companions, on which to base our models. Now, theorists must take into account such large systems as Fomalhaut, and all those super-Jupiters that orbit incredibly close to their stars (what would be within Mercury’s orbit.) I suspect that will be a fruitful field to come!</p><p>There is a lot more that the paper covered that I won’t get into here. Various hypotheses are raised about the planetary atmosphere from the brightness of the planet in different color filters, but this is highly model-dependent and on shaky ground without an actual spectrum. What really fascinated me, as usual, was in the description of HOW the observations were made. Seeing a planet next to a star is a difficult task! Planets are teeny, tiny little guys giving off (more likely reflecting) just a small amount of light compared to the whopping bright furnaces that are their parent stars. The device they used (the the Advanced Camera for Surveys High Resolution Channel in its coronagraphic mode, for the curious) has two occulting spots that literally block the light from the parent star. Images were tried with one, then the other, occulting spot covering the star. However, an occulting spot still leaves a bright halo of light in the image. One way to remove this halo is to image another bright star in this mode, such as Vega, and subtract that halo from the one around Fomalhaut. Another method, and I really thought this was brilliant, was to rotate the instrument for different images. In each successive image, the actual astronomical objects will rotate around your frame, but the errors from the device itself and the halo will stay fixed! Thus errors can be separated from objects. Although these are certainly not new techniques, they have been applied in a way that has let us see exoplanets for the first time, which is just cool. Again, there are more great descriptions of the methods used in the supplement sections of the article, and I highly encourage reading them if you are interested in such things.</p><p>Needless to say, I am impressed at the work of these astronomers in gathering and analyzing all of these data. And, the Hubble Space Telescope, as if you weren’t already impressed with its awesomeness, has added another scientific achievement to a very long list. Since writing this took longer than I thought, I’ll have to summarize my thoughts on the other planetary system to be imaged, HR 8799, some other time!</p><p>Many thanks to the lovely Jo for presenting on this topic in a timely fashion, and the journal club attendees for the great discussion!</p>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-26029463768982784942008-11-16T15:25:00.014-02:002024-03-02T17:35:37.360-03:00Carnival of Space #79<p>Gather around, one and all, for the dazzling display of lights known as the Carnival of Space! But this time, it's not a carnival lit by twinkling bulbs, but by the nuclear furnaces of stars and the fires of our own imagination. This week, we embark on a journey through the planets, starting from Earth and venturing through our solar system to the edges of other star systems beyond.</p><p>The night sky has always been a source of wonder, mystery and enchantment. We stand in awe of the endless twinkling stars and the celestial bodies that grace the skies above. And now, we invite you to join us as we embark on a journey to explore the mysteries of space, to bask in the radiance of stars and to ignite our imaginations.</p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiZ5nffzzyKOmkjbC-_wYaAsauR-1joRuPX4EtG6VnMHvbltoGUGDjkbUlJEYqItlVjC-Az6IldSkxgpC6l-2HOTMOfZGtHnjHb2we4OobjSLjmiCYXiJlB59bEOw07vVXLZ7diSuIV0Jeh5rc106zyvCKWkBMpOYCSs53RPrDL4H5uUJ-Pbd-i4yRCk2Y/s1000/Carnival%20of%20Space.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="562" data-original-width="1000" height="360" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiZ5nffzzyKOmkjbC-_wYaAsauR-1joRuPX4EtG6VnMHvbltoGUGDjkbUlJEYqItlVjC-Az6IldSkxgpC6l-2HOTMOfZGtHnjHb2we4OobjSLjmiCYXiJlB59bEOw07vVXLZ7diSuIV0Jeh5rc106zyvCKWkBMpOYCSs53RPrDL4H5uUJ-Pbd-i4yRCk2Y/w640-h360/Carnival%20of%20Space.jpg" width="640" /></a></div><br /><p>We begin our journey here on Earth, where we are but mere mortals, gazing up at the night sky in wonder. But as we journey through our solar system, we see that we are not alone. The planets, each unique and mysterious in their own way, orbit the sun, their fiery brother. From the gas giants Jupiter and Saturn, with their swirling storms, to the red and dusty Mars, our next-door neighbor, we see the beauty and the power of our solar system.</p><p>And as we journey beyond our solar system, we reach the realm of the stars. The fiery beacons that light up the night sky, each one a mystery waiting to be uncovered. We see the stars in their newborn phase, encased in swirling clouds of gas and dust, and we see them in their death throws, exploding in brilliant supernovae.</p><p>We stand in awe at the vastness of space, the endless expanse of stars and galaxies, and the mystery of what lies beyond. The Carnival of Space is a celebration of the wonder and the beauty of the cosmos. It is a reminder that we are but a small part of something much larger, something that has always been, and always will be, beyond our grasp.</p><p>So come, join us, on this journey through the stars. Let us bask in the light of the horned nuclei of stars, and let us ignite our imaginations as we explore the mysteries of space. This is the Carnival of Space, where the lights are not just twinkling bulbs, but the fires of the cosmos itself. A place where we can all come together to marvel at the beauty of the night sky, and to dream of what lies beyond.</p><p><br /></p><p style="text-align: right;"><i>This text has come from the twisted 'mind' of an artificial intelligence.</i></p><p><br /></p>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-29956558867662465042008-09-04T13:20:00.001-03:002024-03-02T13:28:56.100-03:00Seeing Black Holes<p>A press release from the Center For Astrophysics at Harvard came out yesterday that was SO EXCITING to me that I was bouncing up and down. In today's Nature, astronomers write about the successful attempt to resolve the supermassive black hole at the center of our galaxy using 1.3 mm VLBI. And now you are going, "huh? jargon say what?"</p><p>As most people now know, black holes are supremely dense objects. The gravitational field around them is so strong, they can severely warp space around them, and nothing, not even light, is fast enough to escape its gravitational pull once inside a certain radius. It is a weird concept, since it has essentially infinite density at a single point in space, yet we do find evidence that these things exist. For example, we can watch the orbits of stars around the very center of our Milky Way galaxy, and determine the mass of the dark object that lives there. It has so much mass in such a small area, that physics has no other explanation for what it could be, and any other explanation would be even weirder. Around some black holes, we can measure the orbits of gas, and measure the mass and limit the size.</p><p>Want to visualize where this is? If you look up towards the Southern sky (if you are in the Northern Hemisphere) towards the constellation Sagittarius the hunter, or teapot, and you are at a dark site, then you can look right at the center of the Milky Way galaxy, that band of light that stretches across the sky.</p><p></p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiauuVcQ-qKiR3eJ8Ln6BzhExL0vb7hDMj9YMCfGl_DEa9NyOh3o6UXHGcyPBO-xX6laSNHzUZp0VUek5MUa9wgQcpJXuuhQaWezIYkYz2-CHxF2FalsSsi22bhVxH0E-f2lYSbqM6qQDPgkPrrJPR5eFsEV-ZJtXPtxUMKXBXHX5EN4W24PXHIoKPcojk/s500/black%20hole%20at%20the%20center%20of%20our%20Milky%20Way.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="500" data-original-width="500" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiauuVcQ-qKiR3eJ8Ln6BzhExL0vb7hDMj9YMCfGl_DEa9NyOh3o6UXHGcyPBO-xX6laSNHzUZp0VUek5MUa9wgQcpJXuuhQaWezIYkYz2-CHxF2FalsSsi22bhVxH0E-f2lYSbqM6qQDPgkPrrJPR5eFsEV-ZJtXPtxUMKXBXHX5EN4W24PXHIoKPcojk/w640-h640/black%20hole%20at%20the%20center%20of%20our%20Milky%20Way.jpg" width="640" /></a></div><p>Image from here with caption: "The supermassive black hole at the center of our Milky Way galaxy lies behind dense clouds of gas and dust. The center of the galaxy is a little above the "spout" of the teapot-shaped constellation Sagittarius at the upper right of this photograph."</p><p></p><p>Remember, this is at the very center of the hustle and bustle of our Milky Way, whereas we are way out, 27,000 light years away, in some backwater spiral arm!</p><p>Astronomers want to actually measure the size of these black holes in order to test the theories. Although a black hole by definition gives off no light, the gas swirling around and into it does, giving off radiation at many wavelengths from the radio through the optical and into the x-ray. The Hubble telescope has shown us that supermassive (or millions of times the mass of our sun) black holes exist in the center of almost every galaxy that has a "bulge" in the center. The center, or bulge, of our Milky Way is not easily viewed by us in visible light since we have to look through the plane of the galaxy in order to see it, and there's lots of attenuating dust in the way. But we can see signs of our black hole, dubbed Sgr A*, in the infrared, radio, and x-ray. In order to see something as tiny (at this distance) as the black hole, you need a big, big telescope.</p><p>Enter VLBI, or Very Long Baseline Interferometry. This is a technique by which you link up multiple telescopes across long distances, either in real-time or later in a computer, in order to make one giant telescope. The telescope formed from this can be as big as the Earth! It isn't a very sensitive telescope, but it has very good angular resolution, meaning it can see very tiny, tiny things. In this study, they achieved a resolution of "37 micro-arcseconds - the equivalent of a baseball seen on the surface of the moon, 240,000 miles distant," by linking up telescopes in Hawaii, Arizona, and California. The light that they were tuned to has a wavelength of 1.3 mm, so this can also be called "millimeter wave interferometry."</p><p>So, go ahead and read the press release for more information on what they found and what theory they are testing. In summary, they were able to detect the structure and size of things around the black hole, thus squeezing in to see how small the black hole really is. But there is more work to be done! "Future investigations will help answer the question of what, precisely, they are seeing: a glowing corona around the black hole, an orbiting "hot spot," or a jet of material."</p><p>Other than the fact that this is really cool science, I was personally excited about this since I learned all about these experiments back in 2003 when I was at MIT Haystack Observatory for a summer internship. I'm really glad to see that the team is succeeding in their goal after years of hard work.</p><div><br /></div>MS2http://www.blogger.com/profile/11765803565278277995noreply@blogger.com0tag:blogger.com,1999:blog-8629619257268950091.post-27256254436511763312008-05-29T23:45:00.001-03:002024-03-02T18:59:23.244-03:00Mars Madness<div style="text-align: justify;">Lots of cool news has been floating around on the Phoenix Mars lander. It has taken its first snapshots of the Martian north polar cap, and will be beginning its three-month scientific mission. Keep yourself updated on the project site! The first few days seem to drag out... take pictures of site, take pictures of self, do checks, move arm... but everything on a robotic planetary mission must be done with extreme caution and care. If something gets stuck, no one can drive out there and give it a kick or solder on a new part. There is no on-site operator. I'm pretty thankful that my project is only a 2.5 hour drive away for such reasons! And so all of these things are done with extreme precision, and the science has to be planned very carefully. </div><div style="text-align: justify;"><br /></div><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivBF3i9-xNWBTkkbEsEeEpkn0QHYMAdAKmY5elhgzes9tivv7g_tC8O7fvf7NAWE4my8pBMdyeYa8SA8wDt7n14KQcgPyulerFAUIefeS3noObNlfajGW6TZBBRePmYTYB4DZCt8BGb9IoNXJWergxP6m8tC4zeChFck_MrBFV8epJWWR8yY6CE4yTW8g/s1600/Phoenix%20Mars%20lander.webp" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="1109" data-original-width="1600" height="444" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEivBF3i9-xNWBTkkbEsEeEpkn0QHYMAdAKmY5elhgzes9tivv7g_tC8O7fvf7NAWE4my8pBMdyeYa8SA8wDt7n14KQcgPyulerFAUIefeS3noObNlfajGW6TZBBRePmYTYB4DZCt8BGb9IoNXJWergxP6m8tC4zeChFck_MrBFV8epJWWR8yY6CE4yTW8g/w640-h444/Phoenix%20Mars%20lander.webp" width="640" /></a></div><div style="text-align: justify;"><br /></div><div style="text-align: justify;">One particular image of the lander during its descent was captured by the Mars Reconnaissance Orbiter, and it's absolutely stunning. It's so incredible, that the BadAstronomer even makes a video to express the wonder and awe at this fantabulous image. My favorite quote from that...</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">"This is what science does... We don't just wonder, we actually go and take a look."</div><div style="text-align: justify;"><br />
</div><div style="text-align: justify;">*Update* Check out detailed Phoenix coverage by the Planetary Society!</div>Cebhttp://www.blogger.com/profile/13685023457071437706noreply@blogger.com0