How planets evolve into the diverse worlds we see in our universe remains one of the most pressing questions for scientists to unpack how we got here and where we are going.
Now, a group of scientists is using Webb Space Telescope data to solve a mystery that emerged from the veteran space telescope 20 years ago, upending what planetary scientists already know about how the early Earth lived. Formed from the cosmic ether.
In 2003, the Hubble Space Telescope detected what appeared to be Oldest known planetIt is a giant world that is about 13 billion years old. The discovery raises questions about how such worlds could have formed when their host star was young and contained only a small amount of heavier elements. They are a key component in the formation of planets as we know them.
In new research The team used the Webb telescope. It is a state-of-the-art space observatory that can observe some of the oldest light detected. to study stars in nearby galaxies that are similarly deficient in heavy elements The team discovered that those stars have planet-forming disks. And those disks are older than the young stars in our own galaxy.
“With Webb, we have clear confirmation of what we saw with Hubble. And we need to rethink how we model planetary formation and early evolution. How could it happen in a young universe?'' said Guido de Marchi, a researcher at the European Center for Space Research and Technology. and the lead author of this research study at NASA. release–
in a new study published in the journal Astrophysics earlier this month. The team observed stars in NGC 346, a cluster of stars in the Small Magellanic Cloud. Stars range in mass from about 0.9 times the mass of our sun to 1.8 times the mass of our star.
The team found that even the oldest stars they looked at were still accumulating gas. And the star appears to have a disk around it. This confirms Hubble's observations from the mid-2000s, which revealed stars tens of millions of years old that still have planet-forming discs. They are generally thought to decay after a few million years.
In summary, the team wrote in a report that their findings “Suggests that in low-metal environments Spherical disks could survive longer than previously thought.”
Researchers believe the disk can become stuck for two reasons. One possibility is The absence of heavy elements is beneficial to the dish. This makes them more resistant to the star's radiation pressure. If not, it will quickly explode. Another possibility is that Sun-like stars formed from large clouds of gas. They take longer to break down simply because they are larger.
Elena Sabbi, chief scientist at the National Science Foundation's Gemini Observatory which is part of the foundation's NOIRLab said: “When there is more matter around a star, the accretion lasts for a longer time,” “The disk takes ten times longer to disappear. This has an impact on how planets are created. And what types of system architectures can you have in these different environments? This is very exciting.”
The team used the Webb Space Telescope's Near Infrared Spectrograph (NIRSpec) to examine stars passing through the Small Magellanic Cloud. Last year, a team of scientists used NIRSpec to see sandy clouds On a nearby exoplanet earlier this year This tool is used to detect the first thing called Einstein zigzag In space, it is very different from the spectrographs in the old Webb space observatories. NIRSpec. Observe 100 targets simultaneously Accelerate the rate of crawling and discovery by proxy.
Looking at both ancient and modern star-forming regions could help clarify the origins of our solar system, which is about 4.6 billion years old.