demotemplate2

Star-Forming Region LH 72

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiNUg4MIA7I-K7vBoK-RUQe0D3D8kedicSkIBuKaAYggvBSqbR0uzpa_6jKkDeafyB4OI17dxG88NXElrXz4cUixN8Sa1N_0jSmfWQRjZzorM-p8oGMQpKrsacn8tdGb33Ih7mTzZAKxabK/s1600/Star-Forming-Region-LH-72.jpg" imageanchor="1"><img alt="Star-Forming Region LH 72" border="0" data-original-height="1078" data-original-width="1100" height="627" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiNUg4MIA7I-K7vBoK-RUQe0D3D8kedicSkIBuKaAYggvBSqbR0uzpa_6jKkDeafyB4OI17dxG88NXElrXz4cUixN8Sa1N_0jSmfWQRjZzorM-p8oGMQpKrsacn8tdGb33Ih7mTzZAKxabK/s640/Star-Forming-Region-LH-72.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">In one of the largest known star formation regions in the Large Magellanic Cloud (LMC), a small satellite galaxy of the Milky Way, lie young and bright stellar groupings known as OB associations. One of these associations, called LH 72, was captured in this dramatic NASA/ESA Hubble Space Telescope image. It consists of a few high-mass, young stars embedded in a beautiful and dense nebula of hydrogen gas.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Much of the star formation in the LMC occurs in super-giant shells. These regions of interstellar gas are thought to have formed due to strong stellar winds and supernova explosions that cleared away much of the material around the stars creating wind-blown shells. The swept-up gas eventually cools down and fragments into smaller clouds that dot the edges of these regions and eventually collapse to form new stars.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">The biggest of these shells, home to LH 72, is designated LMC4. With a diameter of about 6000 light-years, it is the largest in the Local Group of galaxies that is home to both the Milky Way and LMC. Studying gas-embedded young associations of stars like LH 72 is a way of probing the super-giant shells to understand how they formed and evolved.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">This image was taken with Hubble’s Wide Field Planetary Camera 2 using five different filters in ultraviolet, visible and infrared light. The field of view is approximately 1.8 by 1.8 arcminutes.</div><br />Image Credit: ESA/Hubble, NASA and D. A. Gouliermis<br />Explanation from: https://www.spacetelescope.org/images/potw1147a/

Star-Forming Region LH 72

In one of the largest known star formation regions in the Large Magellanic Cloud (LMC), a small satellite galaxy of the Milky Way, lie young...

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Januari 22, 2018

Volcán de Colima Eruption

Volcán de Colima Eruption

Colima, Mexico January 26, 2017 Image Credit & Copyright: Sergio Tapiro

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Januari 21, 2018

Globular Cluster Messier 79

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgOqK3hGKID9kGMtxdxwA1CJnZphIE9fNOAvNjUIr-QgCUI2eRSOv4xS7l9qLc2xwNuDkf5krQGXZx_X3xKWv_KDGqM3kAUbUuDsLNK0xsQleshW1hy3_dCVFGOF_3O2PBhl6Ms903WZTY0/s1600/Globular-Cluster-Messier-79.jpg" imageanchor="1"><img alt="Globular Cluster Messier 79" border="0" data-original-height="1002" data-original-width="1503" height="427" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgOqK3hGKID9kGMtxdxwA1CJnZphIE9fNOAvNjUIr-QgCUI2eRSOv4xS7l9qLc2xwNuDkf5krQGXZx_X3xKWv_KDGqM3kAUbUuDsLNK0xsQleshW1hy3_dCVFGOF_3O2PBhl6Ms903WZTY0/s640/Globular-Cluster-Messier-79.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">It’s beginning to look a lot like Christmas in this NASA/ESA Hubble Space Telescope image of a blizzard of stars, which resembles a swirling storm in a snow globe.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">These stars make up the globular cluster Messier 79, located about 40 000 light-years from Earth in the constellation of Lepus (The Hare). Globular clusters are gravitationally bound groupings of up to one million stars. These giant “star globes” contain some of the oldest stars in our galaxy. Messier 79 is no exception; it contains about 150 000 stars, packed into an area measuring just roughly 120 light-years across.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">This 11.7-billion-year-old star cluster was first discovered by French astronomer Pierre Méchain in 1780. Méchain reported the finding to his colleague Charles Messier, who included it in his catalogue of non-cometary objects: The Messier catalogue. About four years later, using a larger telescope than Messier’s, William Herschel was able to resolve the stars in Messier 79 and described it as a “globular star cluster.”</div><div style="text-align: center;"><br /></div><div style="text-align: center;">In this sparkling Hubble image, Sun-like stars appear yellow-white and the reddish stars are bright giants that are in the final stages of their lives. Most of the blue stars sprinkled throughout the cluster are aging “helium-burning” stars, which have exhausted their hydrogen fuel and are now fusing helium in their cores.</div><br />Image Credit: NASA and ESA, S. Djorgovski (Caltech) and F. Ferraro (University of Bologna)<br />Explanation from: https://www.spacetelescope.org/images/potw1751a/

Globular Cluster Messier 79

It’s beginning to look a lot like Christmas in this NASA/ESA Hubble Space Telescope image of a blizzard of stars, which resembles a swirling...

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Januari 19, 2018

Spiral Galaxy NGC 1398

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5NRU81904M0QIxrnInx2CQeTalrlKauDs2HwBa5GC4AHQMsaUHBlBfq-lZwqW3u9CRVQaFjnuVqsO__hTYK1MdmVwYXwyOxVwiU-ULucle4RzIVhouG-8-BnyMbPq2u2qJVjhxBfndOEq/s1600/Spiral-Galaxy-NGC-1398.jpg" imageanchor="1"><img alt="Spiral Galaxy NGC 1398" border="0" data-original-height="1600" data-original-width="1578" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5NRU81904M0QIxrnInx2CQeTalrlKauDs2HwBa5GC4AHQMsaUHBlBfq-lZwqW3u9CRVQaFjnuVqsO__hTYK1MdmVwYXwyOxVwiU-ULucle4RzIVhouG-8-BnyMbPq2u2qJVjhxBfndOEq/s640/Spiral-Galaxy-NGC-1398.jpg" title="" width="631" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">This picture shows spectacular ribbons of gas and dust wrapping around the pearly centre of the barred spiral galaxy NGC 1398. This galaxy is located in the constellation of Fornax (The Furnace), approximately 65 million light-years away.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Rather than beginning at the very middle of the galaxy and swirling outwards, NGC 1398’s graceful spiral arms stem from a straight bar, formed of stars, that cuts through the galaxy’s central region. Most spiral galaxies — around two thirds — are observed to have this feature, but it’s not yet clear whether or how these bars affect a galaxy’s behaviour and development.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">This image comprises data gathered by the FOcal Reducer/low dispersion Spectrograph 2 (FORS2) instrument, mounted on ESO’s Very Large Telescope (VLT) at Paranal Observatory, Chile. It shows NGC 1398 in striking detail, from the dark lanes of dust mottling its spiral arms, through to the pink-hued star-forming regions sprinkled throughout its outer regions.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">This image was created as part of the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.</div><br />Image Credit: ESO<br />Explanation from: https://www.eso.org/public/images/potw1801a/

Spiral Galaxy NGC 1398

This picture shows spectacular ribbons of gas and dust wrapping around the pearly centre of the barred spiral galaxy NGC 1398. This galaxy i...

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Januari 18, 2018

The Bluest of Ice

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiZmv3-T9wSDUOdiMblFIeL-6bNaDsQ-3HtKOWMAn-jkcHiDP04ew2CtxxWj6ndiKvTpqKvbp7eae1EhnqmnonzKG6n9WzynkWAhIwI9KQIwYTbcv2ly7aXRMbhsWyvoRxb-5F9IWVOl5Tg/s1600/Bluest-of-Ice.jpg" imageanchor="1"><img alt="The Bluest of Ice" border="0" data-original-height="1067" data-original-width="1600" height="427" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiZmv3-T9wSDUOdiMblFIeL-6bNaDsQ-3HtKOWMAn-jkcHiDP04ew2CtxxWj6ndiKvTpqKvbp7eae1EhnqmnonzKG6n9WzynkWAhIwI9KQIwYTbcv2ly7aXRMbhsWyvoRxb-5F9IWVOl5Tg/s640/Bluest-of-Ice.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">Acquired on November 29 by Operation IceBridge during a flight to Victoria Land, this image shows an iceberg floating in Antarctica's McMurdo Sound. The part of the iceberg below water appears bluest primarily due to blue light from the water in the Sound. The undersides of some icebergs can be eroded away, exposing older, denser, and incredibly blue ice. Erosion can change an iceberg’s shape and cause it to flip, bringing the sculpted blue ice above the water’s surface. The unique step-like shape of this berg—compared to the tabular and more stable berg in the top-right of the image—suggests that it likely rotated sometime after calving.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Operation IceBridge—an airborne mission to map polar ice—recently made several flights out of the McMurdo and Amundsen-Scott South Pole stations, giving researchers greater access to the interior of the icy continent. For the ninth year in a row, flights over Antarctica have turned up ample science data, as well as spectacular images.</div><br />Image Credit: NASA/Chris Larsen<br />Explanation from: https://www.nasa.gov/image-feature/the-bluest-of-ice

The Bluest of Ice

Acquired on November 29 by Operation IceBridge during a flight to Victoria Land, this image shows an iceberg floating in Antarctica's Mc...

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Januari 17, 2018

π1 Gruis

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEij_StP10On1JXoq1aVAb5o7Yd8doWkdC_H0HFLP1zXGW8WQxSSrwIJ7JEnmGV8eEBzBHKFOWSvGQRThUx8RQrURvZlMEj8unGnxvmiLcgxk2B_TfV7ppa_3rFhh2a0FvLKqyzsolV88qYS/s1600/HD-212087.jpg" imageanchor="1"><img alt="π1 Gruis" border="0" data-original-height="1600" data-original-width="1600" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEij_StP10On1JXoq1aVAb5o7Yd8doWkdC_H0HFLP1zXGW8WQxSSrwIJ7JEnmGV8eEBzBHKFOWSvGQRThUx8RQrURvZlMEj8unGnxvmiLcgxk2B_TfV7ppa_3rFhh2a0FvLKqyzsolV88qYS/s640/HD-212087.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">Astronomers using ESO’s Very Large Telescope have for the first time directly observed granulation patterns on the surface of a star outside the Solar System — the ageing red giant π1 Gruis. This remarkable new image from the PIONIER instrument reveals the convective cells that make up the surface of this huge star, which has 350 times the diameter of the Sun. Each cell covers more than a quarter of the star’s diameter and measures about 120 million kilometres across. These new results are being published this week in the journal Nature.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Located 530 light-years from Earth in the constellation of Grus (The Crane), π1 Gruis is a cool red giant. It has about the same mass as our Sun, but is 350 times larger and several thousand times as bright. Our Sun will swell to become a similar red giant star in about five billion years.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">An international team of astronomers led by Claudia Paladini (ESO) used the PIONIER instrument on ESO’s Very Large Telescope to observe π1 Gruis in greater detail than ever before. They found that the surface of this red giant has just a few convective cells, or granules, that are each about 120 million kilometres across — about a quarter of the star’s diameter. Just one of these granules would extend from the Sun to beyond Venus. The surfaces — known as photospheres — of many giant stars are obscured by dust, which hinders observations. However, in the case of π1 Gruis, although dust is present far from the star, it does not have a significant effect on the new infrared observations.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">When π1 Gruis ran out of hydrogen to burn long ago, this ancient star ceased the first stage of its nuclear fusion programme. It shrank as it ran out of energy, causing it to heat up to over 100 million degrees. These extreme temperatures fueled the star’s next phase as it began to fuse helium into heavier atoms such as carbon and oxygen. This intensely hot core then expelled the star’s outer layers, causing it to balloon to hundreds of times larger than its original size. The star we see today is a variable red giant. Until now, the surface of one of these stars has never before been imaged in detail.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">By comparison, the Sun’s photosphere contains about two million convective cells, with typical diameters of just 1500 kilometres. The vast size differences in the convective cells of these two stars can be explained in part by their varying surface gravities. π1 Gruis is just 1.5 times the mass of the Sun but much larger, resulting in a much lower surface gravity and just a few, extremely large, granules.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">While stars more massive than eight solar masses end their lives in dramatic supernovae explosions, less massive stars like this one gradually expel their outer layers, resulting in beautiful planetary nebulae. Previous studies of π1 Gruis found a shell of material 0.9 light-years away from the central star, thought to have been ejected around 20 000 years ago. This relatively short period in a star's life lasts just a few tens of thousands of years – compared to the overall lifetime of several billion – and these observations reveal a new method for probing this fleeting red giant phase.</div><br />Image Credit: ESO<br />Explanation from: https://www.eso.org/public/news/eso1741/

π1 Gruis

Astronomers using ESO’s Very Large Telescope have for the first time directly observed granulation patterns on the surface of a star outside...

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Januari 03, 2018

Cassiopeia A

<div style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiItkGvHjMC9p7-U2E3DnF6nQOxHFX3CmecJKr59wTC2vItwv6QMukSHIFXIFuqePHwSsNfvXY1vfL95LL4WD7brtagz9tjJIBjXG6IwgYYtkLGXMcD7GnEWcb2A2ctl839LWFFW1AZBUve/s1600/Cassiopeia-A-14.jpg" imageanchor="1"><img alt="Cassiopeia A" border="0" data-original-height="1600" data-original-width="1600" height="640" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiItkGvHjMC9p7-U2E3DnF6nQOxHFX3CmecJKr59wTC2vItwv6QMukSHIFXIFuqePHwSsNfvXY1vfL95LL4WD7brtagz9tjJIBjXG6IwgYYtkLGXMcD7GnEWcb2A2ctl839LWFFW1AZBUve/s640/Cassiopeia-A-14.jpg" title="" width="640" /></a></div><div style="text-align: center;"><br /></div><div style="text-align: center;">Where do most of the elements essential for life on Earth come from? The answer: inside the furnaces of stars and the explosions that mark the end of some stars’ lives.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Astronomers have long studied exploded stars and their remains – known as “supernova remnants” – to better understand exactly how stars produce and then disseminate many of the elements observed on Earth, and in the cosmos at large.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Due to its unique evolutionary status, Cassiopeia A (Cas A) is one of the most intensely studied of these supernova remnants. A new image from NASA’s Chandra X-ray Observatory shows the location of different elements in the remains of the explosion: silicon (red), sulfur (yellow), calcium (green) and iron (purple). Each of these elements produces X-rays within narrow energy ranges, allowing maps of their location to be created. The blast wave from the explosion is seen as the blue outer ring.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">X-ray telescopes such as Chandra are important to study supernova remnants and the elements they produce because these events generate extremely high temperatures – millions of degrees – even thousands of years after the explosion. This means that many supernova remnants, including Cas A, glow most strongly at X-ray wavelengths that are undetectable with other types of telescopes. </div><div style="text-align: center;"><br /></div><div style="text-align: center;">Chandra’s sharp X-ray vision allows astronomers to gather detailed information about the elements that objects like Cas A produce. For example, they are not only able to identify many of the elements that are present, but how much of each are being expelled into interstellar space.   </div><div style="text-align: center;"><br /></div><div style="text-align: center;">The Chandra data indicate that the supernova that produced Cas A has churned out prodigious amounts of key cosmic ingredients. Cas A has dispersed about 10,000 Earth masses worth of sulfur alone, and about 20,000 Earth masses of silicon. The iron in Cas A has the mass of about 70,000 times that of the Earth, and astronomers detect a whopping one million Earth masses worth of oxygen being ejected into space from Cas A, equivalent to about three times the mass of the sun. (Even though oxygen is the most abundant element in Cas A, its X-ray emission is spread across a wide range of energies and cannot be isolated in this image, unlike with the other elements that are shown.)  </div><div style="text-align: center;"><br /></div><div style="text-align: center;">Astronomers have found other elements in Cas A in addition to the ones shown in this new Chandra image. Carbon, nitrogen, phosphorus and hydrogen have also been detected using various telescopes that observe different parts of the electromagnetic spectrum. Combined with the detection of oxygen, this means all of the elements needed to make DNA, the molecule that carries genetic information, are found in Cas A.  </div><div style="text-align: center;"><br /></div><div style="text-align: center;">Oxygen is the most abundant element in the human body (about 65% by mass), calcium helps form and maintain healthy bones and teeth, and iron is a vital part of red blood cells that carry oxygen through the body. All of the oxygen in the Solar System comes from exploding massive stars. About half of the calcium and about 40% of the iron also come from these explosions, with the balance of these elements being supplied by explosions of smaller mass, white dwarf stars.   </div><div style="text-align: center;"><br /></div><div style="text-align: center;">While the exact date is not confirmed, many experts think that the stellar explosion that created Cas A occurred around the year 1680 in Earth’s timeframe. Astronomers estimate that the doomed star was about five times the mass of the Sun just before it exploded. The star is estimated to have started its life with a mass about 16 times that of the Sun, and lost roughly two-thirds of this mass in a vigorous wind blowing off the star several hundred thousand years before the explosion.  </div><div style="text-align: center;"><br /></div><div style="text-align: center;">Earlier in its lifetime, the star began fusing hydrogen and helium in its core into heavier elements through the process known as “nucleosynthesis.” The energy made by the fusion of heavier and heavier elements balanced the star against the force of gravity. These reactions continued until they formed iron in the core of the star. At this point, further nucleosynthesis would consume rather than produce energy, so gravity then caused the star to implode and form a dense stellar core known as a neutron star. </div><div style="text-align: center;"><br /></div><div style="text-align: center;">The exact means by which a massive explosion is produced after the implosion is complicated, and a subject of intense study, but eventually the infalling material outside the neutron star was transformed by further nuclear reactions as it was expelled outward by the supernova explosion.</div><div style="text-align: center;"><br /></div><div style="text-align: center;">Chandra has repeatedly observed Cas A since the telescope was launched into space in 1999. The different datasets have revealed new information about the neutron star in Cas A, the details of the explosion, and specifics of how the debris is ejected into space.  </div><br />Image Credit: NASA/CXC/SAO<br />Explanation from: https://www.nasa.gov/mission_pages/chandra/images/chandra-reveals-the-elementary-nature-of-cassiopeia-a.html

Cassiopeia A

Where do most of the elements essential for life on Earth come from? The answer: inside the furnaces of stars and the explosions that mark t...

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Januari 01, 2018