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Earth lost 40% mass during formation

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Earth lost 40% mass during formation
Earth lost 40% mass during formation. IANS

London, Sep 28: The violent and chaotic process that led to the formation of Earth resulted in the loss of more than 40 per cent of its mass, says a study.

Analysing a mixture of earth samples and meteorites, the scientists shed new light on the sequence of events that led to the creation of our home planet.

Planets grow by a process of accretion – a gradual accumulation of additional material – in which they collisionally combine with their neighbours.

This is often a chaotic process and material gets lost as well as gained, said the study published in the journal Nature.

Massive planetary bodies impacting at several kilometres per second can generate substantial heat which, in turn, produces magma oceans and temporary atmospheres of vaporised rock.

Repeated loss of this vapour envelope during continued collisional growth causes the planet’s composition to change substantially.

“We have provided evidence that such a sequence of events occurred in the formation of the Earth and Mars, using high precision measurements of their magnesium isotope compositions,” said lead researcher Remco Hin from University of Bristol in Britain.

“Magnesium isotope ratios change as a result of silicate vapour loss, which preferentially contains the lighter isotopes. In this way, we estimated that more than 40 per cent of the Earth’s mass was lost during its construction,” he said.

For the study, the researchers analysed samples of the Earth together with meteorites from Mars and the asteroid Vesta, using a new technique to get higher quality measurements of magnesium isotope ratios than previously obtained.

“We now show that vapour loss during the high energy collisions of planetary accretion has a profound effect on a planet’s composition,” Hin said.

“This process seems common to planet building in general, not just for Earth and Mars, but for all planets in our Solar System and probably beyond, but differences in the collision histories of planets will create a diversity in their compositions,” he added. (IANS)

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Three astronauts return to Earth after staying at space station for five months

A Russian Soyuz spacecraft carrying Expedition 53 crew mates naming Randy Bresnik of NASA, Paolo Nespoli of European Space Agency (ESA) and Sergey Ryazanskiy of Roscosmos landed in Kazakhstan at 2.37 p.m. after spending five months a The International Space Station.

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Three astronauts landed on Earth after spending five months at space station.
Three astronauts landed on Earth after spending five months at space station. IANS
  • Three astronauts land in Kazakhstan
  • The astronauts spent nearly five months at The International pace Station
  • The astronauts ventured for three spacewalks

Washington, Dec 14, 2017: Three astronauts landed in Kazakhstan on Thursday after spending nearly five months at the International Space Station.

A Russian Soyuz spacecraft carrying Expedition 53 crewmates Randy Bresnik of NASA, Paolo Nespoli of European Space Agency (ESA) and Sergey Ryazanskiy of Roscosmos landed at 2.37 p.m. Kazakhstan time, NASA said.

During his time aboard the orbital complex, Bresnik ventured outside the space station for three spacewalks.

Along with NASA astronauts Mark Vande Hei and Joe Acaba, Bresnik lead a trio of spacewalks to replace one of two latching end effectors on the station’s robotic arm, Canadarm2.

They also lubricated the newly replaced Canadarm2 end effector and replaced cameras on the left side of the station’s truss and the right side of the station’s US Destiny laboratory.

Ryazanskiy conducted one spacewalk with fellow cosmonaut Fyodor Yurchikhin in August to deploy several nanosatellites, collect research samples and perform structural maintenance.

Bresnik now has spent 150 days in space on two flights. Ryazanskiy now has 306 days in space on two flights. Nespoli has logged 313 days in space on his three flights.

The Expedition 54 crew continues operating the station, with Alexander Misurkin of Roscosmos in command.

The three-person crew will operate the station until the arrival of three new crew members on December 19, NASA said. (IANS)

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Ram Setu : Where Science meets Hindu religion, Science affirms but Congress Party denies

Science Channel affirms that Ram Setu was man made not natural, NASA released images

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Ram Setu
Ram Setu between India and Sri Lanka (Pic by NASA)
  • Science channel affirms that Ram Setu was man- made not natural
  • In 2007 Congress Party submitted an affidavit in court saying Ram Setu is a myth

An American science channel on Tuesday affirmed on the existence of Ram Setu, saying that there exist evidence suggesting that the bridge connecting India and Sri Lanka was man-made not natural.

The Discovery Communications-produced show, “Ancient Land Bridge”, quotes American archaeologists to affirm that 30-mile line between India and Sri Lanka is made up of rocks that are 7,000 years old, older than the sandbar supporting them, which is approx 4,000 years old. The video claims that the structure is man made, not natural, citing images from a NASA satellite. Interestingly, the carbon dating of beaches near Dhanushkodi and Mannar Island sync with the date of Ramayana.

Ram Setu in Ramayana
Ram Setu (Satellite image by NASA)

The description of Ram Setu in Ramayana

In ‘Yuddha Kanda’ of the Ramayana, building of Ram Setu has been described. Rama Setu took 5 days to build by under the supervision of architects Neel and Nala. It is believed that Ram Setu is made of a chain of limestone shoals. It is 30 Km Long and 3 Km Wide. It Starts from Dhanushkodi tip of India’s Pamban Island and ends at Sri Lanka’s Mannar Island. Sea in these areas is very shallow. In Ramayana it is mentioned that the bridge was built by stones and these stone which floated on water by touch of Nala & Neel.

Ram Setu
Pic credit : Promo released by the US-based Science Channel

Politics on Ram Setu

Ram Setu is the historical and archeological evidence of Ramayana. The new findings by NASA have already sparked a political debate in the country with BJP leaders questioning the Congress’ previous stand where the party had told the Supreme Court that there was no historical proof that Lord Rama had ever existed. Congress party made u-turn and claimed they never questioned existence of Lora Ram. But In 2005, the UPA-1 government had proposed a shipping canal project that would have dredged the area and damaged the formation on sea, referred to as the Ram Setu by Hindus. The project was thus challenged by the BJP in the apex court.

Responding on the new affirmations, Minister of State for Home Affairs Kiren Rijiju said, “This is what the BJP has been saying all along.” Firebrand BJP leader Subramanian Swamy said, “the US scientists said what was already know”. On Tuesday, Smriti Irani posted the trailer of the show on her Twitter account, saying, “Jai Shri Ram.”

Ram Setu is the national heritage of India and it must be preserved.

– by Shaurya Ritwik, Shaurya is Sub-Editor at NewsGram and writes on Geo-politcs, Culture, Indology and Business. Twitter Handle – @shauryaritwik

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NASA’s plan on getting Martian samples to Earth

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NASA brings Martian samples to Earth from Mars.
NASA brings Martian samples to Earth from Mars. IANS
  • NASA plans on getting Martian samples to Earth from Mars
  • To know if life existed anywhere other than on Earth

Washington, Dec 11: (IANS) NASA has revealed how it plans to bring back Martian samples to Earth for the first time with the help of its next rover mission to the Red Planet, Mars 2020.

After landing on Mars, a drill will capture rock cores, while a caching system with a miniature robotic arm will seal up these samples. Then, they will be deposited on the Martian surface for possible pickup by a future mission, NASA said.

“Whether life ever existed beyond Earth is one of the grand questions humans seek to answer,” said Ken Farley of NASA’s Jet Propulsion Laboratory in Pasadena, California.

“What we learn from the samples collected during this mission has the potential to address whether we’re alone in the universe,” Farley said.

Mars 2020 relies heavily on the system designs and spare hardware previously created for Mars Science Laboratory’s Curiosity rover, which landed in 2012.

Despite its similarities to Mars Science Laboratory, the new mission has very different goals – it will seek signs of ancient life by studying the terrain that is now inhospitable, but once held flowing rivers and lakes, more than 3.5 billion years ago.

To achieve these new goals, the rover has a suite of cutting-edge science instruments.

It will seek out biosignatures on a microbial scale.

An X-ray spectrometer will target spots as small as a grain of table salt, while an ultraviolet laser will detect the “glow” from excited rings of carbon atoms.

A ground-penetrating radar will look under the surface of Mars, mapping layers of rock, water and ice up to 10 metres deep, depending on the material.

The rover is getting some upgraded Curiosity hardware, including colour cameras, a zoom lens and a laser that can vaporise rocks and soil to analyse their chemistry, NASA said.

The mission will also undertake a marathon sample hunt.

The rover team will try to drill at least 20 rock cores, and possibly as many as 30 or 40, for possible future return to Earth, NASA said.

Site selection has been another milestone for the mission. In February, the science community narrowed the list of potential landing sites from eight to three.

All three sites have rich geology and may potentially harbour signs of past microbial life. But a final landing site decision is still more than a year away.

“In the coming years, the 2020 science team will be weighing the advantages and disadvantages of each of these sites,” Farley said.

“It is by far the most important decision we have ahead of us,” Farley said.

The mission is set to launch in July/August 2020. (IANS)