For the first time ever, astronomers have directly captured a photo of exoplanet forming near a young star, a discovery expected to shed light on the process of planet formation around other stars.
Although, we had never seen the process of planet formation directly, we understand it. So, HOW DO PLANETS FORM? Our models suggest that at the birth of a star in a cloud of dust and gas (mostly hydrogen) called a nebula, the remaining dust and gas, which are not all collapsed under the influence of gravity that formed the star, will constitute the protoplanetary disk, the raw materials for planet building. In this disk, the material within it travels around the star in the same direction. Eventually, the material in the disk will begin to stick together, growing bigger and bigger. Soon, the beginnings of planets — ‘planetesimals’ as they are called — are taking shape.
But between knowing the process and directly observing it, there is still a giant step to be taken … yet. Today, we have what is claimed as “the first image of an extrasolar planet formation” taken by the telescopes of the University of Arizona.
The planet in question is called LkCa 15b. It resides in a young, three-planet system called LkCa 15, located in the constellation Taurus 450 light-years away from us. The host star LkCa 15 is just like our sun but only two million years old, a young star, astronomical speaking, surrounded by a special kind of protoplanetary disk with a gap — some 50 times wider than distance between Earth and the sun.
To date, more than 2,000 exoplanets (planets which orbit a star other than the sun) were discovered but only about 10% have been photographed, none are still in the formation stage.
This is the first time that we’ve imaged a planet that we can say is still forming,
says Steph Sallum ~ lead author of a paper in the journal Nature.
Results like this have only been made possible with the application of a lot of very advanced new technology to the business of imaging the stars. And it’s really great to see them yielding such impressive results,
To carry out this difficult observation, researchers used instruments including the 8.4-m Large Binocular Telescope, the largest telescope in the world, located on Mount Graham in Arizona, and UA’s Magellan Telescope and its adaptive optics system, located in Chile.
That’s because of astronomers at the University of Arizona (UA) who have developed the instruments and techniques that make that difficult observation possible.
The researchers also employed a new technique to look for protoplanets, wherein they searched for the light emitted by hydrogen as the gas falls toward a newly forming planet — its “hydrogen alpha” fingerprint. The process produces a signature red glow, “just like a neon sign,” Laird Close, a University of Arizona astronomy professor and Follette’s graduate adviser, said in the statement.
That single dark shade of red light is emitted by both the planet and the star as they undergo the same growing process,
Kate Follette ~ co-author.
We were able to separate the light of the faint planet from the light of the much brighter star and to see that they were both growing and glowing in this very distinct shade of red.
Astronomers says that more work is needed to explain the giant planet’s location and why it is still growing. The team will continue monitoring LkCa 15 b to better understand the planet formation process, as well as the fingerprint it leaves on the transition disc.
One of the fundamental human questions is whether we’re alone or unique,
It’s cool to look at Jupiter-like exoplanets like LkCa 15 b, but ultimately we’re trying to push the technology to be able to detect Earth-like exoplanets. I’ve always been inspired by the famous ‘pale blue dot’ image of Earth taken by Voyager as it passed Saturn. We’d really like to do that some day for a planet around another star, and this sort of work is moving us in that direction.