Incredibly, it’s been a week since the ESA probe ROSETTA arrived at Comet 67P and the first truly close-up views of its surface were revealed to the world. I’m hoping that means that there will be some new OSIRIS images released today, as it seems to be a once a week deal, but we’ll have to wait and see. In the meantime, there will almost certainly be a new NAVCAM image to drool over later this afternoon, because, true to their word, ESA are now releasing those daily, allowing us all to virtually fly alongside (or sit on!) Rosetta as she keeps pace with the comet, and see what she sees.
The pics released over the past few days have been very interesting. We’re now seeing parts of the nucleus we hadn’t seen before, and it’s now very clear that the surface of 67P is a very complicated, very tortured place indeed, scarred and sculpted by processes and events as yet unknown, but which will hopefully become clearer as the days, weeks and months pass…
Above: August 9th image (enhanced by myself)
Above: August 10th ESA image, and below, same image cropped, rotated and enhanced by myself, simply to make it look more dramatic, I’ll admit! 😉
Above: image taken on August 11th, cropped and enhanced by myself to bring out surface texture and features.
Looking at those images, 67P seems quiet and serene, almost asleep, but in truth there is a lot of activity going on right now, and I really hope ESA soon releases some images exposed to show the jets and spurts of gas and dust shooting out of the nucleus.
It’s incredible to think that in a year’s time 67P will be at its closest point to the Sun – “perihelion” – and will be at its mist active, and the images sent back by Rosetta should show great jets, plumes and gouts of icyy, dusty material shooting off the nucleus, the surface fracturing and cracking, and more. But before then we get to watch the comet “wake up”, and see how it changes over time. That’s something cometary astronomers and armchair explorers have dreamed for doing for a long, long time, and pretty soon comparing ROSETTA’s images taken on different days should start to reveal changes on the surface. Really looking forward to that!
In the meantime, I;m sure that the ROSETTA team are frantically putting together their first maps of the nucleus, to help with identifying possible landing sites for the probe’s “Philae” lander. Philae is a fascinating spacecraft in its own right, and if all works well will provide us with the first ever images taken from a comet’s surface, which will be truly historic. To find out more about the plans for Philae’s departure from ROSETTA and its landing on the comet, I emailed some questions to Dr Hermann Böhnhardt, lead scientist for the Philae lander, and he was very generous with his time and sent me back replies almost right away!
How many "departure" images of the orbiter do you plan on taking with the cameras onboard Philae after separation from Rosetta? HBO: Less than a handful, since the lander has to balance the internal mass storage and data uplink to the orbiter for all activities of the separation, descent and landing.
During the descent, will the cameras onboard Rosetta take any images of Philae? HBO: This is mostly in the hands of the orbiter planning, but I assume that they will try, and even after landing Osiris should be able to image the lander, at coarse resolution though.
During the descent, will the cameras onboard Philae take any wide angle images of the nucleus of 67P? HBO: yes, this is the plan and a task of the Rolis camera.
After landing, will the cameras onboard Philae be able to take wide angle "landscape images" of the comet's surface, or will they be focussed on the ground close to the lander? HBO: CIVA is meant to take images of the landscape of the landing site just after landing when the Sun is up. The cameras shall provide a 360 deg view covering the sky, the landscape to the horizon and even parts of the landing legs (namely the soles of the landing pads). The ground close to the lander will be imaged by Rolis just (i.e. seconds) before touch-down.
How soon do you expect images taken by Philae to be released after they have been taken? HBO: The landscape images and also other available science and engineering data will be used to assess where and how Philae has landed at the surface. This is a task for the first hours just after landing since the subsequent sciops of the lander depends on this information. We expect to have direct data and commanding to the lander via the orbiter by the time of Philae touch-down and some time window thereafter which will be used to uplink the data from the descent and touch-down to Earth. This should include also the landscape and ground images. The Civa images are foreseen to be released immediately after reception and pipeline processing to the lander and ESA Rosetta teams for analysis. Release to the public is a decision to be taken by the CIVa PI and ESA. My expectation is that images from the lander will come out shortly (less than 24h) after they have arrived on ground.
Looking forward to November's landing even more now!
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