One of the most common and, nevertheless, challenging way to discover exoplanets is taking pictures of a planet. Most of the time, the images of exoplanets are artists’ impressions of how they would look like. Now, we have the first direct photo of two young alien worlds. The scientists captured on the image two baby exoplanets pinching gas from their host star.
We now have the first direct photo of baby exoplanets orbiting a young star
PDS 70 is a young star system located at 370 light-years away from Earth and placed in the constellation Centaurus. While observing it in a previous study, researchers discovered an exoplanet orbiting around PDS 70. Now, they spotted another one. The image the astronomers took shows that the star system is still in its early age, and it provides precious testimonies about how planetary systems form and evolve, being the second multi-planet system observed by direct imaging. However, it’s the first photo of a young exoplanetary system.
The European Southern Observatory’s Very Large Telescope from Chile had directly imaged in the protoplanetary disk of PDS 70 the new planet, PDS 70c. The first confirmed planet to be directly imaged in 2018 was PDS 70b. Its mass is estimated between 4 and 17 times greater than Jupiter, and it orbits approximately as far away from its star as Uranus orbits from our Sun. The new planet, PDS 70c orbits about as far as Neptune does from our Sun, weighing less than its sister planet, at between 1 and 10 Jupiter masses.
The two baby exoplanets are pinching gas from their host star
With the system being so young, about 6 million years old, the central star is surrounded by a disk of gas and dust. A significant gap in this disk have been cleared out by the planets stretching about 1.9 to 3.8 billion miles away and which are now surrounding the star in this gap.
These baby exoplanets appear to be the source of these gaps in the dust clouds surrounding the young star. The planets’ gravity pinches nearby material inwards, as they orbit, and vac all of the nearby dust and gas, creating a gap. In the end, a planet will stop growing when the material runs out. This process is well known by our researchers, who strongly believe that this is the way the planets in our solar system formed. Unfortunately, in so many other systems we can’t see the planets themselves, only the gaps being visible.
Astronomers’ theories of how planets form are stronger due to the discovery of these two baby exoplanets and gaps in the PDS 70 young star system. Acting like Jupiter and Saturn with their resonance shaping a large part of the solar system’s early history, the two planets of PDS 70 system are orbiting in a resonance, having the inner planet circling its star twice as often as the outer planet. It is known for a fact that resonances like these can cause the planets to migrate over time.