Categories: Comets

A Comet Seen at the end of its Life. It’s covered in talcum powder

Astronomers finally managed to observe a comet nearing the end of its life. And they found that it’s covered in talcum powder. They have no idea why.

It’s usually very tough to observe the nucleus of a comet. When comets come close enough to observe, they become active. Any volatile ices, like water and ammonia, evaporate under the intense heat of the sun, giving them their characteristic coma. While a pretty sight for stargazers, the coma obscures the nucleus.

When comets are far from the sun and inactive, they’re pretty much too far away to observe.

But in 2016 astronomers got lucky with Comet P/2016 BA14 (PANSTARRS). When it was first discovered, it was mistaken for an asteroid, but follow-up observations revealed that it was actually the burnt-out husk of a comet. After so many trips too close to the sun, it had simply lost almost all of its ices.

In March of 2016, a team of astronomers from the National Astronomical Observatory of Japan (NAOJ) and Koyama Astronomical Observatory of Kyoto Sangyo University used the Subaru telescope to monitor the comet as it approached within 3.6 million kilometers of Earth – a rare opportunity to get a (relatively) closeup view of such a strange comet near the end of its life.

They found that the surface of P/2016 BA14 is covered with organic molecules and large grains of phyllosilicate.

On Earth, you may be more familiar with large grains of phyllosilicate as talcum powder.

Analysis of the talcum found that the comet had once been heated to over 330 degrees Celsius, which is far hotter than its current orbit allows. This suggests that at one time the comet managed to pass much closer to the sun.

However, the team isn’t sure if the talcum was there all along – and just exposed once the comet lost its coma – or it formed later on.

“This result provides us a precious clue to study the evolution of comets.” comments Dr. Takafumi Ootsubo, the lead author of this research, “We believe that further observations of the comet nuclei will enable us to learn more about the evolution of comets.”

Paul M. Sutter

Astrophysicist, Author, Host | pmsutter.com

Recent Posts

The Moon’s Ancient Volcanoes Could Have Created Ice Sheets Dozens of Meters Thick

Everyone loves looking at the Moon, especially through a telescope. To see those dark and…

8 hours ago

Spacesuits are Leaking Water and NASA is Holding off any Spacewalks Until They can Solve the Problem

NASA's spacesuits are getting old. The extra-vehicular mobility units - EMUs for short - were…

11 hours ago

Starliner Launches Successfully, but Two of its Thrusters Failed

Boeing's CST-100 Starliner successfully launched and rendezvoused with the ISS, a crucial step towards performing…

12 hours ago

NASA is Building a Mission That Will Refuel and Repair Satellites in Orbit

NASA is planning a mission to demonstrate the ability to repair and upgrade satellites in…

21 hours ago

The “Doorway on Mars” is More Like a Dog Door

Mars Curiosity rover took a panorama of this rock cliff during its trip across Mount…

1 day ago

Thanks to Gaia, Astronomers are Able to Map Out Nebulae in 3D

In this 2D image of nebulae in the Orion Molecular Complex, the submillimetre-wavelength glow of…

2 days ago