Small Solar System Discovered, and the Youngest Rocky Planets Ever Found
By: April Carson
Two of the most unique solar systems uncovered to date. Astronomers have reported discovering what is considered a “miniaturized” mini-solar system and another star system home to some of youngest rocky planets discovered so far, making them an excellent place for further research into this field!
The astronomers have just announced that an international team led by the Center for Astrobiology (CAB) has measured the mass of seven exoplanets, located in two multiple planetary systems. The first system contains four planets which are reduced versions of our own Solar System and one planet out there may actually hold some very young rocky worlds - believed so far to be only 2-3 thousand years old! This latest discovery opens up vast opportunities for studying early phases on Earth's formation but also helps us understand how life evolved here as well.
One of the great questions in astrobiology is how we can find life on other planets. As more and more are discovered, it's becoming clearer that this question has an answer - over 4 thousand so far! The first step was taken by NASA back in 1990 with their discovery of exoplanets (a type of planet orbiting stars besides our Sun). This year alone marks a new milestone; as June 2nd 2020 comes around there are 5 219 candidate explains waiting for us to explore them thoroughly enough to know whether or not they contain some form of life.
With these discoveries it's starting to become clear that the best place for life is a planet orbiting a star, rather than a star itself or other galactic objects such as black holes and neutron stars. We've only found the occasional system with multiple planets around one star yet, but scientists are hopeful that recent advances in technology will allow them to find more in the near future.
The discovery of extrasolar planets is one that has revolutionized astronomy. To understand their atmospheres, it's necessary to measure accurately the mass and size for each planet in a system- but how does this work? The K2 Collaboration is made up of researchers from the European Southern Observatory (ESO), who designed an instrument with HARPS at La Silla Observatory (Chile) to investigate these unique planets without doubt or error; they refer to themselves as the K2 Collaboration.
Two multi-planetary systems, the K2-32 system, made up of four planets, and the K2-233 system, a young planetary system (less than 400 million years old) with three planets, have been investigated in relation to this collaboration by a scientific team directed by the CAB.
However, they are all in orbits that are twice as small as those of Mercury. K2-32 is one of the few multi-planetary systems with four or more known planets, all of whose planet masses and radii have been determined.
K2-233 is a second planetary system that astronomers investigated. It contains two Earth-sized, rocky inner planets (K2-233 b and K2-233 c) and a mini-Neptune outer planet (K2-233 d). Jorge Lillo Box, a researcher at the CAB's María de Maeztu Unit, was the first author on the article. The team also included scientists from other Spanish institutions such as IAC and IAA as well as international collaborators.
They are the youngest rocky planets known to date, with densities comparable to Earth. This is the first time that planetary history as early as Earth's can be studied.
Finally, as proven by astronomers, all of these planets transit (eclipse their star), making them a good reference for future studies using the James Webb Space Telescope to analyze their atmospheres. According to David Barrado, CAB researcher and co-author of the article, “...there are relatively few planets whose ages are known in a sufficiently accurate manner as those detected around the star MWC 480. In fact, this system's properties provides a 'snapshot' of planetary evolution similar to that seen on Earth five billion years ago".