If you want to drive astronomers crazy at a party, casually ask them how planets form.
Despite 400 years of modern astronomy, many compelling theories, and countless supercomputer-powered simulations, we still don’t know much about how a young star’s disc of debris becomes an orderly solar system.
Blinding starlight and incredible distances make it hard to learn about what’s going on in planetary nurseries.
However, a team of astronomers on Monday released what they say is the first-ever image of a newborn planet.
In the photo above, the planet’s parent star, called PDS 70, is blocked out in the center to help astronomers see the planetary disc around it. The baby world, named PDS 70b, appears as the bright orange-yellow blob just off to the right and below. (The large oval is farther-out dust and gas that may form new planets.)
“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 Kepler, a researcher at the Max Planck Institute for Astronomy who helped lead the research, said in a press release. “The problem is that until now, most of these planet candidates could just have been features in the disc.”
Astronomers took the image of the newborn planet with the Very Large Telescope, which is actually an array of four observatories in the high Atacama desert of northern Chile. Specifically, the scientists used an instrument called SPHERE, which was built within the last decade to study far-off planetary systems.
At just 5.4 million years old, the infant planet is very youthful compared to Earth, which is more than 4.5 billion years old.
The star, PDS 70, is about 82% as massive as the sun and 370 light-years from Earth.
The baby planet takes 120 Earth-years to orbit the star, at a distance of about 22 astronomical units. One astronomical unit is the distance between the sun and Earth, or nearly 93 million miles. So if you dropped PDS 70b into our own solar system, the world would orbit somewhere between Uranus and Neptune.
PDS 70b has an atmosphere — but it’s no place you’d want to visit. Astronomers who’ve studied the data believe the world is a gas giant whose atmosphere is about 1,000 degrees Fahrenheit, which is hot enough to melt lead. The planet is also as hefty as a few Jupiters, which is on the upper range of planethood. If it were any larger, it’d be considered a type of failed star called a brown dwarf.
Researchers now hope to use the new image to sorting through a raft of conflicting theories about when solar systems are built, how quickly, and by what means.
“This discovery shows us that we are finally able to find and study planets at the time of their formation,” Thomas Henning, an author on both studies, said in a press release. “That is the fulfilment of a long-cherished dream.”