Tuesday December 12, 2017
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Comets: The harbingers of life on earth?

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Rosetta

 

By K.S.Jayaraman

Bengaluru: Did a comet strike jump-start life on Earth? The findings of the European Space Agency’s Rosetta Mission tend to suggest this possibility.

An instrument on board the Philae Lander of Rosetta Mission has identified 16 organic molecules on the surface of a comet that are potentially “prebiotic”, or necessary for life, the mission scientists have reported in a recent issue of the journal Science.

“These are the first organic molecules to be ever reported directly, from in-situ analyses, from the surface of a comet,” Chaitanya Giri, a co-investigator of Cometary Sampling and Composition Experiment (COSAC) of the Rosetta Mission and one of the authors, told IANS.

On November 12, 2014, Philae Lander became the first space probe to soft land on the surface of a comet called 67P/Churyumov-Gerasimenko. Besides COSAC, Philae carried several scientific experiments on board, with each trying to decipher the nature of the comet.

COSAC – which is a gas chromatography-mass spectrometer – aimed to study the surface ‘organic’ chemical composition of the comet, said Giri, a post-doctoral research scientist in the Department of Planets and Comets at the Max Planck Institute for Solar System Research (MPS) in Gottingen, Germany.

According to the report, the Philae Lander bounced off the comet’s surface multiple times after the touchdown before coming to rest. The dust cloud kicked up from the bounces entered the COSAC instrument, which analysed the dust. “The entire COSAC team studied the mass spectra data generated by it,” Giri said.

The COSAC team, led by Fred Goesmann, involved scientists from France, Germany, Ireland, the Netherlands, Spain, Switzerland and the United States. Giri, the only Indian on board, has been part of the team for the past five years in various capacities, beginning as a trainee doctoral student.

According to the Science report, as many as 16 molecules were identified by the experiment. Twelve of these had been reported earlier from remote ground-based telescopes and fly-by missions whereas COSAC has reported four novel molecules that have never been reported earlier, Giri said.

These new molecules are acetamide, methyl isocyanate, propionaldehyde and acetone. Other re-reported molecules include hydrogen cyanide, formamide and glycolaldehyde.

“All these molecules are of great significance for triggering pre-biotic chemistry – the precursor processes towards the formation of life,” Giri said. These are the same molecules that are known to be the building blocks for the origin of life on Earth and are major constituents of known molecular biological processes, he said.

For instance, Glycolaldehyde is known to play a crucial role in the prebiotic synthesis of sugars. Hydrogen cyanide is a known and important precursor for synthesis of amino acids and nucleobases. Formamide and acetamide are known to play a crucial act in the formation of nucleobases and phosphorylation of nucleosides to nucleotides. Within their chemical structure they also contain the so-called “CONH” bond that is the only known way to polymerize amino acids into peptides and further into proteins.

“For centuries, comets have been regarded as omens of destruction,” Giri said. “Our findings have revolutionized human perception of comets. The COSAC-reported potentially prebiotic molecules now point to the likely role of comets as harbingers of life on Earth.”

However, many important questions yet remain unanswered and further exploration of comets and other small bodies is indicated, he added.

“Rosetta is an icon of international co-operation, public support and state-of-the-art science and technology. Such missions are crucial prerequisites for human advancement in outer space. The knowledge gained through Rosetta urges us to explore even further,” he said.

(IANS)

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Researchers Claim The Existence Of Planet Nine

Researchers from an American University have laid evidences to prove the presence of Planet Nine

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Planet Nine
Kuiper Belt indicates the presence of Planet Nine
  • The science communities since a long time have been debating upon the existence of Planet Nine. 
  • Space highlights different shreds of evidence based on which scientists are stating the claim.

What Is Planet Nine?

Planet Nine is a hypothetical planet present in the far outer Solar System, whose mass is estimated to be 10 times more than the mass of Earth. The planet is said to be 20 times farther than the sun than Neptune is.

What Do Researchers Have To Say?

Dr Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology, said that there were five different lines of observational evidence which pointed to the existence of Planet Nine. He stated that if this theory does not sound believable, then people would have to come up with the answers of the five pieces of evidence which could lead to further confusion.

Also Read: Five Students from Telangana Selected for the NASA Human Exploration Rover Challenge

Batygin in 2016 published a study examining the six known objects in the Kuiper Belt, a  circumstellar disc in the Solar System beyond the planets that extends from the orbit of Neptune towards interstellar space.

The study examines all the objects have elliptical orbits pointing in the same direction and are tilted the same way. These serve as evidence to the planet’s existence.

It is being said that the objects are tilted 30 degrees downward compared to the plane where the eight official planets circle the sun. Researchers also made use of computer simulations of the solar system including the Planet Nine and to demonstrate that there should be more objects tilted a whopping 90 degrees to solar plane. It was revealed that five such objects, which fit these parameters were already known.

The study led to the birth of two more ideas. Researchers said that this planet could have tilted the planets of the solar system during the last 4.5 billion years.

Planet Nine’s existence could also tell the reason as to why Kuiper Belt objects orbit in the opposite direction as compared to other things in the solar system.

-Prepared by Megha Acharya of NewsGram.

(the story was originally published in PTI)

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Hubble captures farthest active inbound comet

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nasa's hubble space telescope

Washington, Sep 29: NASA’s Hubble Space Telescope has captured the farthest active inbound comet ever seen, at a whopping distance of 1.5 billion miles from the Sun.

Slightly warmed by the remote Sun, it has already begun to develop an 80,000-mile-wide fuzzy cloud of dust, called a coma, enveloping a tiny, solid nucleus of frozen gas and dust, according to a study published in the Astrophysical Journal Letters.

These observations represent the earliest signs of activity ever seen from a comet entering the solar system’s planetary zone for the first time.

The comet, called C/2017 K2 (PANSTARRS) or “K2”, has been travelling for millions of years from its home in the frigid outer reaches of the solar system, where the temperature is about minus 226 degrees Celsius.

Comets are the icy leftovers from the formation of the solar system 4.6 billion years ago and therefore pristine in icy composition.

“K2 is so far from the Sun and so cold, we know for sure that the activity — all the fuzzy stuff making it look like a comet — is not produced, as in other comets, by the evaporation of water ice,” said lead researcher David Jewitt of the University of California, Los Angeles.

“Instead, we think the activity is due to the sublimation (a solid changing directly into a gas) of super-volatiles as K2 makes its maiden entry into the solar system’s planetary zone. That’s why it’s special. This comet is so far away and so incredibly cold that water ice there is frozen like a rock,” Jewitt said.

Based on the Hubble observations of K2’s coma, Jewitt suggests that sunlight is heating frozen volatile gases – such as oxygen, nitrogen, carbon dioxide, and carbon monoxide – that coat the comet’s frigid surface.

These icy volatiles lift off from the comet and release dust, forming the coma. Past studies of the composition of comets near the Sun have revealed the same mixture of volatile ices.

“I think these volatiles are spread all through K2, and in the beginning billions of years ago, they were probably all through every comet presently in the Oort Cloud,” Jewitt said.

“But the volatiles on the surface are the ones that absorb the heat from the Sun, so, in a sense, the comet is shedding its outer skin. Most comets are discovered much closer to the Sun, near Jupiter’s orbit, so by the time we see them, these surface volatiles have already been baked off. That’s why I think K2 is the most primitive comet we’ve seen,” Jewitt added.(IANS)

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Landmark Achievement: 6 Astronomers from India Discover Giant Radio Galaxies (GRGs)

A team of 6 astronomers from India have reportedly discovered Giant Radio Galaxies (GRGs) which are the largest known galaxies in the universe

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Giant Radio Galaxies
Out of total known galaxies, only 300 have been classifies as Giant Radio Galaxies. Wikimedia
  • Six astronomers from India have recently discovered the largest galaxies known to the universe, called Giant Radio Galaxies (GRGs)
  • Only 300 out of total number of galaxies are classified as Giang Radio Galaxies
  • The research was successful taking into account the research of last 6 decades of radio astronomy

July 06, 2017: A team of six astronomers from India has made a landmark discovery. Using the research from last six decades of radio astronomy and a 20-year-old survey, the team has detected the existence of Giant Radio Galaxies (GRGs).

Giant Radio Galaxies are known to be the largest galaxies in the universe. The reason for their large size is unknown as of now. As one of the lead researcher, Pratik Dabhade from Inter-University Centre for Astronomy and Astrophysics (IUCAA), explains in the study, “The huge size of GRGs has defied any theoretical explanation so far. Our work will help in understanding how these galaxies grow to be so large.”

The other researchers also involved include Joydeep Bagchi (IUCAA), Mamta Pommier (CNRS Observatoire de Lyon), Madhuri Gaikwad (Max Planck Institute Bonn), Shishir Sankhyayan (IISER Pune) and Somak Raychaudhary (IUCAA).

Also Read: “Do not Stand and Drink Water”: Here is Why it is often said so

Their research has been published in Journal Monthly Notices of the Royal Astronomical Society. The Giant Radio Galaxies are found co-existing with a supermassive black hole at the core of center of the nucleus. High energy particles are discharged at the speed of light which emerges into two giant radio lobes.

The Giant Radio Galaxies are known to be the last stage of evolution of galaxies, mainly because of their massive size. However, these galaxies are visible only through radio telescopes.

– by Saksham Narula of NewsGram. Twitter: @Saksham2394