Rosetta’s Comet Keeps On Jetting Even After the Sun Goes Down

67P/Churyumov-Gerasimenko certainly isn’t a comet that dreads sundown. Images acquired by the OSIRIS instrument aboard ESA’s Rosetta spacecraft in April 2015 reveal that some of the comet’s dust jets keep on firing even after the Sun has “set” across those regions. This shows that, as the comet continues to approach its August perihelion date, it’s now receiving enough solar radiation to warm deeper subsurface materials.

“Only recently have we begun to observe dust jets persisting even after sunset,” said OSIRIS Principal Investigator Holger Sierks from the Max Planck Institute for Solar System Research.

The image above was captured by OSIRIS on April 25 and shows active jets near the center, originating from shadowed areas on the comet’s smaller “head” lobe. The region is called Ma’at – see maps of 67P’s regions here and here.

(Also it looks kind of like an overexposed image of a giant angry lemming. But that’s pareidolia for you.)

Detail of the active jets. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

It’s thought that the comet has now come close enough to the Sun – 220.8 million kilometers, at the time of this writing – that it can store heat below its surface… enough to keep the sublimation process going within buried volatiles well after it rotates out of direct solar illumination.

Read more: What Are Comets Made Of?

Comet 67P and Rosetta (and Philae too!) will come within 185.9 million km of the Sun during perihelion on Aug. 13, 2015 before heading back out into the Solar System. Find out where they are now.

Source: ESA’s Rosetta blog

Jason Major

A graphic designer in Rhode Island, Jason writes about space exploration on his blog Lights In The Dark, Discovery News, and, of course, here on Universe Today. Ad astra!

Recent Posts

Lunar Night Permanently Ends the Odysseus Mission

On February 15th, Intuitive Machines (IM) launched its first Nova-C class spacecraft from Kennedy Space…

3 hours ago

Webb Joins the Hunt for Protoplanets

We can't understand what we can't clearly see. That fact plagues scientists who study how…

6 hours ago

This Supernova Lit Up the Sky in 1181. Here’s What it Looks Like Now

Historical astronomical records from China and Japan recorded a supernova explosion in the year 1181.…

8 hours ago

Hubble Sees a Star About to Ignite

This is an image of the FS Tau multi-star system taken by the Hubble Space…

9 hours ago

This Black Hole is a Total Underachiever

Anyone can be an underachiever, even if you're an astronomical singularity weighing over four billion…

10 hours ago

Someone Just Found SOHO's 5,000th Comet

The Solar and Heliospheric Observatory (SOHO) was designed to examine the Sun, but as a…

10 hours ago