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Pasta Shaped Rock — Sign of Life on Red Planet Astrosat Peers Into The SPACE STORIES — A SNAPSHOT Pasta Shaped of this kind of extensive filamentous rock on other planets, we would know Rock — Sign it’s a fingerprint of life.” He further added, “It’s big and it’s unique. No of Life on Red other rocks look like this. It would be definitive evidence for the presence of Planet alien microbes.” Sulfuri can survive in extremely ESEARCHERS at the Illinois hot, fast-flowing water bubbling up from University, USA, have found a underground hot springs. The bacteria Rkind of rock on the red planet can withstand exposure to ultraviolet light which appears like Fettuccine Pasta. and most importantly survives only in It is believed that the formation of environments with extremely low oxygen such type of unusual shape and structure levels, using sulfur and carbon dioxide of the rocks on the earth is controlled by as energy sources. These are the special a bacteria called Sulfurihydrogenibium traits which make it a suitable candidate yellowstonense (Sulfuri). This bacteria to colonize on Mars and other planets. is ancient and can withstand harsh According to Bruce Fouke, environments that are similar to the “Bacteria form tightly wound cables condition on Mars. The appearance of that wave like a flag that is fixed on such rock on the planet indicates that one end. These Sulfuri cables look these bacteria once lived on Mars. amazingly like fettuccine pasta, while The research was published in the Bruce Fouke, Geology Professor further downstream they look more like journal Astrobiology. at the University who led the NASA- capellini pasta,” he added. “This should funded study, told the Illinois News be an easy form of fossilized life for a Source: Illinois University (news.illinois.edu) Bureau that, “If we see the deposition rover to detect on other planets.” in this cavity region for at least the last have old stars and there has been no AstroSat Peers 100 million years. recent formation of stars in them,” Galaxies are very large aggregates explained K. George, who carried into the Heart of billions of stars held by gravitation. out the study at the Indian Institute of Milky Way, our home galaxy, is Astrophysics, Bengaluru. of Jellyfish believed to house nearly ten billion stars A blue galaxy can become red if it with the Sun as one among them. On a stops forming stars. Galaxies may stop Galaxy larger scale, it has been found that even forming stars due to various processes galaxies flock together due to gravity in within the galaxy itself such as the effect HE Ultraviolet Imaging groups of hundreds to thousands, known of the supermassive black hole at the Telescope onboard India’s space as galaxy clusters. centre; the presence of a rectangular bar- Tobservatory, AstroSat, has The region between these galaxies like structure which is made up of stars provided an insight into processes at is filled with very hot gas whose and located near the centre; or massive work in the heart of a jellyfish galaxy. temperature can be as high as millions explosions accompanying stellar death Researchers who studied the of degrees. As a galaxy moves through called supernovae. The stripping of gas anatomy of a jellyfish galaxy called this hot gas, some of the cold gas from the galaxy due to its motion in the JO201 have found that it comprises in the galaxy's outer regions can be a central bright region surrounded pulled back, leading to the formation by a bright broken ring-like emission of stars in structures that resemble structure. Ensconced in between is a tails or tentacles. This gives them the cavity or void like region of rather faint appearance of jellyfish, and hence, ultraviolet emission. The ultraviolet light teir name jellyfish galaxies. One such from the bright ring is due to young stars jellyfish galaxy is JO201, which has formed in the last 200 to 300 million been studied by astronomers from India years. and abroad as a part of an international By comparing this with images from collaboration called GASP. other telescopes at different wavebands, “Galaxies come in two researchers have shown that the cavity is varieties — those that appear blue have due to the scarcity of young stars. This young stars and are the star-forming means no new stars have been formed variety, while red ones are those which Ultraviolet image of the centre of the Jellyfish galaxy JO201 imaged using AstroSat. The cross marks the 54 | Science Reporter | September 2019 position of active galactic nucleus in the galaxy. New Mechanism Explaining the Disappearance of Methane on Mars HE planet Mars has always been speculated for the existence of life due to its similarities to the Earth. Nearly Tfifteen years ago the first observance of methane on Mars aroused great interest around the scientific world. However, a mysterious phenomenon is the presence and disappearance of methane on the planet. Sometimes very low concentrations can also be measured which is not a mis-measurement but rather a mechanism responsible for the disappearance of methane in Simulation of wind erosion on Mars. Image Credits: Mars Simulation the atmosphere. Laboratory, AU Though various mechanisms have been proposed explaining the production of methane but the reasons for the disappearance This is the process which is more effective than of methane remained unidentified. An interdisciplinary group photochemical processes explaining how methane gets removed of researchers at Aarhus University, Denmark, conducted from the atmosphere and then deposits in the soil within the an investigation and proposed a mechanism explaining the observed time periods. disappearance of methane on Mars. Researchers investigating Scientists have also demonstrated that these mineral surfaces for years have suggested that in a Mars-like atmosphere, wind- can form reactive chemicals, for example, hydrogen peroxide driven erosion can be responsible for the disappearance of and oxygen radicals, which are extremely poisonous to living methane from the Mars atmosphere. Importantly, they explained creatures, including bacteria. that wind-generated saltation can oxidize minerals and ionize The outcomes are significant for evaluating the likelihood of gases like methane causing bond formation between ionized life on or close to Mars' surface. In various follow-up studies, methane and minerals. the specialists will analyze what is happening with the bound The researchers based their study on Mars-analogue minerals, for example, basalt and plagioclase, and demonstrated methane and whether the erosion procedure in addition to the that these solids can be oxidized and gases are ionized during the gases in atmosphere likewise changes or even totally evacuates erosion process. In this manner, the ionized methane reacts with more complex organic material, which can either originate on the mineral surfaces and bonds to them. Subsequently, the team Mars itself or has come to Mars as a feature of shooting stars. demonstrated that the carbon atom, for example, methyl group The study has been published in Icarus. from methane, bonds to the silicon particle in plagioclase, which is likewise a dominant compound of Mars' surface material. Source: Aarhus University (https://international.au.dk/) hot gas between galaxies in a cluster because of the AGN, and not due to tail-like structure, far out in the galaxy. could also impede the formation of stars. young stars. The energy released from According to the authors, this galaxy Regarding the curbing of star- the AGN heats up cold gas clouds is unique as it provides direct evidence formation in this galaxy, researchers present close by. As stars are formed of internal and external mechanisms at favour the hypothesis of the Active from cold gas clouds, this heating of work to halt the formation of stars in Galactic Nucleus (AGN). Most large gas leads to an arrest of star formation. the galaxy. galaxies are believed to possess This, in turn, results in a scarcity of The research results have been supermassive black-holes at their young stars giving the galaxy a cavity- centres. The mass of these supermassive accepted for publication in the journal like appearance around the AGN. black holes could be hundreds of Monthly Notices of Royal Astronomical The incomplete ring structure seen thousands to billions of times the mass Society. The team included scientists with lack of ultraviolet towards the left of Sun. The gas and dust from the from the GASP collaboration and the of the bright ring is explained due to neighbourhood swirling at very high Indian Institute of Astrophysics. velocities into the supermassive black the lack of young stars in this region. hole increase the brightness of the However, in this case, this cessation Sarita Vig, India Science Wire central region multi-fold, and the galaxy of star-formation is explained due to [Sarita Vig is an astrophysicist and an is said to pass through an AGN phase. external effects, a result of gas being associate professor at the Indian Institute In JO201, it is reported that the stripped out from this galaxy. Notice of Space Science and Technology (IIST), central region is bright in ultraviolet that this is the same side which has the Thiruvananthapuram] September 2019 | Science Reporter | 55 that the jet is in the direction of Scorpius constellation. The Indian Astronomers find explosion should have resulted in a compact stellar object such as a neutron star or a pulsar or a black hole. However, there Evidence of Supernova is no trace of either yet. Massive stars with a mass more than 8-10 times that of our Remnants Sun end up as supernova explosions. The explosions brighten to intensity of million suns for a few days and then slowly fade OR several centuries, astronomers have been fascinated into oblivion. The bursts throw up vast amounts of gas and by large explosions that occur at the end of a star’s particles at high velocity in all directions and they appear mostly Flifecycle, resulting in a phenomenon called supernova.
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