Skip to main content

Remember that alien comet? Scientists figured out what it’s made of

Late last year, astronomers grabbed the public’s attention when they announced they has observed an alien comet. 2I/Borisov, as it was named, had traveled to our solar system from a different planetary system, making it a very rare visitor. Now, a study of the comet using data from the Hubble Space Telescope has revealed more about its composition and origin.

There was great interest in studying the comet because of its unusual status. “With an interstellar comet passing through our own solar system, it’s like we get a sample of a planet orbiting another star showing up in our own back yard,” said John Noonan of the Lunar and Planetary Laboratory at the University of Arizona.

Recommended Videos

The researchers found that the coma of the comet, or the envelope which forms around its nucleus, had a larger amount of carbon monoxide than water ice. In fact, its ratio of carbon monoxide to water ice was three times greater than any comet we’ve seen in our solar system.

Please enable Javascript to view this content

That was unexpected, as carbon monoxide shifts from ice to gas very easily, much more so than water ice, so typically you find a lot more water ice than carbon monoxide ice. It also had carbon monoxide in its inner layers that were revealed when outer layers were stripped away as it passed close to the sun.

Comet 2I/Borisov
Comet 2I/Borisov NASA , ESA , K. Meech (University of Hawaii), and D. Jewitt (UCLA)

That tells astronomers that the comet’s home system must have been unusual as well. “Borisov’s large wealth of carbon monoxide implies that it came from a planet formation region that has very different chemical properties than the disk from which our solar system formed,” astrophysicist Dennis Bodewits, the study’s lead author from Auburn University in Alabama, said in a statement.

“Because of the abundance of carbon monoxide ice that survived so close to the Sun, we think that comet Borisov comes from a much colder place and from a very different debris disk around a star than our own.”

Astronomers believe that the comet was formed a long way away from its star, which is why its carbon monoxide didn’t largely sublimate away. They also think that, because of its very high speed (it traveled through our solar system at 21 miles per second), the comet must have been kicked out of its system by a passing star or giant planet.

Studying this object is not merely a curiosity, however, as it can also teach astronomers about the evolution of different planetary systems. “We’ve been studying the composition of comets here for decades and using this information to understand how planets in our solar system formed and evolved,” said Kathleen Mandt, a planetary scientist and study author from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.

“Measuring the composition of a comet from another planetary system was an opportunity we couldn’t miss!”

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
Microsoft is making a major change to using your iPhone in Windows
The Dell XPS 13 on a table with the Start Menu open.

In a recent Windows Insider Blog post, Microsoft announced it's adding the option for iPhone users to access their phones from the Start menu. Thanks to a special widget next to the Start menu, when you connect your phone, you can see data such as notifications, battery indicators, recent contacts, connection status, and more.

To enjoy this feature, you must use the recent Windows 11 preview build from the Dev and Beta channels, and you must be a Windows Insider. You must also update the Phone Link app to version 1.24121.30.0 or higher, have a Microsoft account, and have a PC that supports Bluetooth LE. Microsoft said it does not support PCs running Pro Education or Education SKUs. Even if this doesn't affect you, the update is rolling out in phases, so reaching your PC might take some time if you don't already have it.

Read more
Where to buy the RTX 5090 and RTX 5080 today
The RTX 5080 sitting on a pink background.

The day is finally upon us -- Nvidia's best graphics cards are here, and you can buy them now. The RTX 5090 and the RTX 5080 are now available at various retailers, both online and in brick-and-mortar stores. There's just one problem: The cards may suffer from limited availability, so the sooner you shop, the better.

While we expect these GPUs to sell out quickly over the next few weeks, it's still possible to buy them today. Find out where to buy the RTX 5090 and the RTX 5080 today.
RTX 5090

Read more
Microsoft is killing this popular Word feature and replacing it with AI
Microsoft word document.

In a Microsoft Support blog post, the software giant announced the end of a helpful feature called Smart Lookup available in Word. It appears like an attempt to get users to use Microsoft's Copilot AI. The feature has been around since 2016, and it gives users definitions, relevant links, and synonyms directly inside of Word. Now, it's gone for good.

Nevertheless, if you right-click on a word and choose Search from the context menu, you will see only an empty search panel. Some users will see a message saying, "Sorry, something went wrong. Please try again," while others will see a blank space that never stops loading. Microsoft even removed the Smart Lookup feature from the standalone Office 2024 suite.

Read more