Category Archives: Comet 67P/Churyumov-Gerasimenko

Comet 67P/Churyumov-Gerasimenko, rosetta, rosetta spacecraft

It’s the Pits On Comet 67P

Leave a comment

From Sinkholes to Jets

Active areas with sinkholes and pits on the Seth Region of Comet 67P/Churyumov-Gerasimenko. The central pit is about 220 meters across and 185 meters deep. Courtesy ESA/Rosetta/MPS for OSIRIS team/MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

It’s quite a week for solar system exploration news. Pluto (which is way more than a planet!) continues to be on everybody’s mind with the upcoming close flyby of the New Horizons mission.  Dwarf planet Ceres is still getting the once-over from Dawn. And, today we’re starting to get more high-resolution images from the Rosetta mission’s OSIRIS camera as it scans Comet 67P/Churyumov-Gerasimenko.  Check out this latest image, showing sinkholes and pits on the surface. It’s more than likely they play an important role in creating the jets of dust we see flowing away from the nucleus. A number of the dust jets trace back to these pits, and that’s giving mission scientists a peek into the interior processes that drive those outbursts.

Active Pits and Sinkholes

Scientists have found at least 18 pits, sort of circular in shape, across various parts of the cometary nucleus. They range in size from a few tens of meters across to a few hundred meters. The deepest ones are around 210 meters, and their floors seem to be covered in dust. Other images of the comet show dust jets rising up from fractures in the walls of the pits. The fractures mean that there are volatiles (gases and ices) just below the surface. AS those materials get warmed by the Sun, they expand, and that forces cracks into the sinkhole walls. The trapped materials, plus dust, come rushing out of the cracks and out to space, creating the jets we’ve all been seeing emanating from the comet.

The pits likely form as the materials rush out, leaving behind a cavity under the surface. The cavities could also have existed since the comet was formed, or some other heating caused ices to vent out after the upper layers warmed up. However the cavities formed, eventually their ceilings can’t hold up any more, and they collapse, creating the pit.

Comet 67P is due to make its closest approach to the Sun on August 13, 2015. The Rosetta spacecraft is orbiting the comet’s nucleus and will be charting how the comet changes up to, during, and after perihelion. The newly awakened Philae lander may also contribute observations, depending on how well it can communicate with the orbiter. This mission is giving us all a new look at some very old ice as it makes its passage through our part of the solar system.

Want to follow the mission? Check out the Rosetta mission pages for more images and announcements.

 

Comet 67P/Churyumov-Gerasimenko, rosetta, rosetta spacecraft

Philae Phones Home

1 Comment

Rosetta’s Lander says “Can You Hear Me Now?”

Artist’s conception of the Philae lander on the surface of Comet 67P/Churyumov-Gerasimenko. In reality, it landed somewhere near a large cliff, and teams are still pinpointing the spot. ESA/ATG medialab

I woke up today to great news that the Rosetta mission’s Philae lander has been awake for a short time now and finally was able to phone home. The mission controllers reported that it talked with the ground team for about 85 seconds, sending data. More than 300 packets have been analyzed and the team is hoping to retrieve more than 8,000 data packets stored on the lander’s onboard memory.  That information would give the science teams a good look at the most recent experiences Philae has had since waking up at some point before it phoned home.

This is really fantastic news, folks. It means that — if Philae stays awake and communicative — that we’ll have “boots on the ground” during the comet’s perihelion passage in mid-August. We’ll get reports from the comet as it warms up during closest approach to the Sun, and get some great images of the landscapes during that time, not to mention temperature and other data.

Want to follow along on Philae’s adventure? I’ll write about it as it comes and you can always go check out the Rosetta Blog for the latest updates!  I’ve written more about the Rosetta mission here and here.

Good to hear from you, Philae!  And, now Rosetta scientists can figure out just where you’re resting by using your signals to triangulate in on you.