Space and astronomy news
Astronomers have watched the young binary star system SVS 13 for decades. Astronomers don’t know much about how planets form around proto-binary stars like SVS 13, and the earliest stages are especially mysterious. A new study based on three decades of research reveals three potentially planet-forming disks around the binary star.
Continue reading “Planets Have Just Started to Form in This Binary System”
Can one type of planet become another? Can a mini-Neptune lose its atmosphere and become a super-Earth? Astronomers have found two examples of mini-Neptunes transitioning to super-Earths, and the discovery might help explain a noted “gap” in the size distribution of exoplanets.
Continue reading “Mini-Neptunes can Lose gas and Turn Into Super-Earths”
When young stars coalesce out of a cloud of molecular hydrogen, a disk of leftover material called a protoplanetary disk surrounds them. This disk is where planets form, and astronomers are getting better at peering into those veiled environments and watching embryonic worlds take shape. But young stars aren’t the only stars with disks of raw material rotating around them.
Some old, dying stars also have disks. Can a second generation of planets form under those conditions?
Continue reading “A Second Generation of Planets can Form Around a Dying Star”
When it comes to observing protoplanetary disks, the Atacama Large Millimetre/sub-millimetre Array (ALMA) is probably the champion. ALMA was the first telescope to peer inside the almost inscrutable protoplanetary disks surrounding young stars and watch planets forming. ALMA advanced our understanding of the planet-forming process, though our knowledge of the entire process is still in its infancy.
According to new observations, it looks like chaos and disorder are part of the process. Astronomers using ALMA have watched as a star got too close to one of these planet-forming disks, tearing a chunk away and distorting the disk’s shape.
What effect will it have on planetary formation?
Continue reading “A Star Passed too Close and Tore Out a Chunk of a Protoplanetary Disk”
It’s one of nature’s topsy-turvy tricks that the deep interior of the Earth is as hot as the Sun’s surface. The sphere of iron that resides there is also under extreme pressure: about 360 million times more pressure than we experience on the Earth’s surface. But how can scientists study what happens to the iron at the center of the Earth when it’s largely unobservable?
With a pair of lasers.
Continue reading “There’s So Much Pressure at the Earth’s Core, it Makes Iron Behave in a Strange Way”
Our conventional models of planet formation may have to be updated, according to a pair of new papers.
Accretion is the keyword in current planet formation theory. The idea is that the planets formed out of the solar nebula, the material left over after the Sun formed. They did this through accretion, where small particles accumulate into more massive objects. These massive boulder-sized objects, called planetesimals, continued to merge together into larger entities, sometimes through collisions. Eventually, through repeated mergers and collisions, the inner Solar System was populated by four rocky planets.
But the new research suggests that the collisions played out much differently than thought and that objects collided with each other several times, in a series of hit and runs, before merging. This research fills some stubborn holes in our current understanding.
Continue reading “The Early Solar System was Messier and More Violent Than Previously Believed”
New research shows that other sunlike stars in our galaxy aren’t so kind to their planets. Up to a quarter of them may consume planets before they even establish a solar system. That consumption leaves behind a distinct chemical fingerprint in the stars, which can help researchers understand how common planetary systems are…and how often they get destroyed.
Continue reading “Many Sunlike Stars Gobbled up Some of Their Planets”
One of the less appreciated aspects of George Lucas’ vision for Star Wars was that he predicted the existence of planets in binary star systems years before we saw even the first exoplanet. Now a team from the University of Cambridge and the Max Planck Institute for Extra-terrestrial Physics have found how exactly those planets can form without being torn apart by their accompanying suns.
Continue reading “This is how you get Tatooines. Binary Star Planet Formation”
Planetary formation theory has been undergoing a lot of changes recently, with an ever expanding litany of events that can potentially impact it. Everything from gravity to magnetic fields seems to impact this complex process. Now scientists want to add another confounding factor – massive solar flares thousands of times more powerful than the most powerful we have ever observed from the Sun.
Continue reading “The Sun is Mellow Yellow Today. Billions of Years Ago? Not So Much”
Magnetic fields are great for lots of things – directing explorers, levitating trains, and containing nuclear fusion reactions are just an example of what these invisible forces can do. Now we can ascribe another feature to magnetic fields – they can give planets a rocky core.
Continue reading “Does Mercury Have a big Iron Core Because it’s so Close to the Sun’s Magnetic Field?”