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Indian American student in team that discovers Jupiter-like planet
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By Arun KumarWashington, Aug 14
An international team of
astronomers, including an Indian-American PhD student, has discovered a
Jupiter like exoplanet outside earth's solar system just a 100 light
years away.
Researchers including Rahul I. Patel, a PhD student
in Physics & Astronomy Department of Stony Brook University, New
York, are calling the exoplanet a "young Jupiter" because it shares many
characteristics of Jupiter.
A paper outlining the full findings is published in Science.
The
finding could serve as a decoder ring for astronomers to understand how
planets formed around the sun as it provides an opportunity to look at
younger star systems in the earlier phase of development, according to a
media release.
Called 51 Eridani b, the exoplanet is the
'faintest' one on record, and also shows the strongest methane signature
ever detected on an alien planet, which should yield additional clues
as to how the planet formed.
"We found that 51 Eridani is surrounded by warm dust that indicates the presence of an asteroid belt," said Patel.
"Finding dust around a star is like seeing a large signpost that tells us there might be a planet," he added.
"This
is because the dust is usually created when lots of large asteroids
collide and destroy each other, usually pushed around by a large planet -
like 51 Eridani b."
Patel led NASA's Wide-field Infrared Survey
Explorer (WISE) to search for any thermal glow that dust and ice grains
resulting from collisions among asteroids and comets in the Solar System
can produce.
His previous work identifying recycled planetary
dust, known as "debris disks," around close to a hundred other star
systems, puts the discovery of the exoplanet in context.
In
addition to being the faintest planet ever imaged, it's also the coldest
- 400 Celsius, whereas others are around 700 °C - and features the
strongest atmospheric methane signal on record.
Previous
Jupiter-like exoplanets have shown only faint traces of methane, far
different from the heavy methane atmospheres of the gas giants in our
solar system.
All of these characteristics, the researchers say,
point to a planet that is very much what models suggest Jupiter was like
in its infancy.
Patel and Stanimir Metchev, a Physics &
Astronomy Professor at Western University in Canada and at Stony Brook
University, are co-investigators on the scientific study.
They
are both members of the international Gemini Planet Imager Exoplanet
Survey (GPIES) team, which is dedicated to imaging and characterising
exoplanets, planets discovered outside of earth's solar system.
"What
makes 51 Eridani particularly interesting is that it also harbours dust
and ice in the planetary system," explained Metchev.
"These are much like the dust and the ice grains produced by collisions among asteroids and comets in the Solar System."
More
data from the European Space Agency's Herschel Space Observatory reveal
that 51 Eridani is also surrounded by a more distant and colder
cometary belt, much like the Kuiper Belt of comets beyond Neptune in the
Solar System."
The two belts - the asteroid and the cometary
belt around 51 Eridani - fall on either side of the newly discovered
planet 51 Eridani b.
"The overall structure bears striking
resemblance to our own Solar System, with Jupiter as the most massive
planet orbiting between a belt of asteroids and a belt of comets,"
explained Metchev.
"In 51 Eridani, we are therefore seeing what
the Solar System resembled at a very young age, around the time when the
Earth was still forming."
(Arun Kumar can be contacted at [email protected])