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| This is the first clear image of a planet caught in the act of formation around the dwarf star PDS 70. |
Here is a reprint of the July 2, 2018 CNN article by Ashley Strickland, announcing the new planet:
A planet-hunting
instrument has captured the first confirmed image of a newborn planet that's
still forming in our galaxy.
To the right of the black circle at the center
of the image, the round bright planet can be seen within the disk of gas and
dust around the young dwarf star PDS 70. Of course, the center isn't naturally
this dark. Instead, the researchers used a coronagraph to block the bright
light of the star in order to look at the disk and the planet.
It's carving out a path through the disk
around the star, which is in the Centaurus constellation. The protoplanetary
disk is the "planet factory" full of gas and dust around young stars.
The planet was found in a gap in this disk, which means it is close to where it
was born and still growing by accumulating material from the disk.
The planet, dubbed PDS 70b, was detected by an
international team using the European Southern Observatory's Very Large
Telescope in Chile and its planet-hunting instrument, called SPHERE. The
instrument is considered to be one of the most powerful planet hunters in
existence.
The discovery by two teams of researchers is
detailed in two papers published in the journal Astronomy & Astrophysics on Monday.
"These discs around young stars are the
birthplaces of planets, but so far only a handful of observations have detected
hints of baby planets in them," Miriam Keppler of the Max Planck Institute
for Astronomy, who led one team, said in a statement. "The
problem is that until now, most of these planet candidates could just have been
features in the disc."
André Müller, also with the Max Planck
institute and leader of the second team, said in a statement that
"Keppler's results give us a new window onto the complex and
poorly-understood early stages of planetary evolution. We needed to observe a
planet in a young star's disc to really understand the processes behind planet
formation."
SPHERE was able to measure the planet's
brightness at different wavelengths, which enabled the researchers to determine
the properties of its atmosphere.
This is incredibly challenging, because even
though SPHERE used the coronagraph to block the star, it had to seek out the
planet's signal in multiple ways.
Researchers were able to determine that it's a
giant gas planet and has a blisteringly hot surface temperature of 1,832
degrees Fahrenheit. This is at least a few times the mass of Jupiter, the
largest gas giant in our solar system, and well above the highest temperature
recorded on any planet in our solar system.
They also deduced that it has a cloudy
atmosphere.
Although the planet looks close to its star in
the image, it's 1,864,113,576 miles away. That's the same distance as Uranus
from our sun. It takes the planet 120 years to orbit the star, which fits with
astronomers' predictions that gas giants would need to form quite far from
their stars.
Directly imaging the planet is a game-changer. Going forward, researchers will be able test models of how planets form and learn more about the history of how the earliest planetary systems formed, like our own solar system.
"After more than a decade of enormous efforts to build this high-tech machine, now SPHERE enables us to reap the harvest with the discovery of baby planets!" Thomas Henning, director at the Max Planck Institute for Astronomy and leader of the teams, said in a statement.
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| Proto-torus shape. Energy from the middle; containment from the boundary. Chalk drawing by Cyd Ropp. |
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