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Closing in on 67P…

As I write this – on a wet and windy afternoon in Kendal, when the Cumbrian Sky isn’t fifty but a hundred different shades of grey – the ESA Rosetta probe is now less than 1000km from the icy nucleus of Comet 67P. And while there has been no increase in the number of hi resolution images being released by the OSIRIS camera team (time to face facts, Stu: They Just Don’t Care what people out here want  to see… get over it… move on…) the navcam images are being released daily, which is brilliant, and yesterday a new OSIRIS image was released, and we are starting to see actual features on the nucleus. Let’s take a look at the latest images.

First, here’s the navcam image released yesterday…

30 July NAVCAM

That image confirms the basic shape of the comet – a small part and a large part stuck together in the middle – and there are tantalising hints of features on its surface. Now, the first thing people like me do when an image like that is released is to fire up our favourite image processing programs and try to sharpen it up and bring out details lurking in it. It’s a very inexact thing, and everyone who does it… well, most people who do it… are well aware that as soon as you start messing about with carefully manipulating and enhancing images like that you run the risk of actually adding features which aren’t there, confusing matters for everyone. Sharpening, boosting contrast and altering the curves of an image can introduce imaging artefacts to it, giving the impression of craters, hills and other features which aren’t actually there. So, I had a go on that latest navcam image, and this is what came out the other end…

30 July NAVCAMb

…which looks sharper, yes, and does give the impression of a cratered and hilly body, but really, there’s no way of knowing if anything there is real or not, so it’s just a bit of fun really.

However, the new OSIRIS image does show some real detail, most people are agreed, and here it is…

Comet_on_29_July_2014

Now, something as reasonably sharp as that will stand up to some enhancing and manipulating, so what does it look like after a spot of that?

Comet_on_29_July_2014b

Now that IS interesting… can’t wait to see the next OSIRIS image (but I’ll have to for another week – I know! Stop it!!) which will surely tell us just how cratered the nucleus is. It should also tell us if there is a big boulder sitting on the nucleus (that big black thing roughly in the centre of the nucleus, perhaps sitting on a ridge overlooking the “waist” of the nucleus..?

Comet_on_29_July_2014d

There is a lot more coverage of Rosetta’s mission on t’internet now, as more and more bloggers and science writers wake up to the fact that something very special indeed is a about to happen – Mankind’s first rendezvous with, and landing on, a comet. But some have been covering the story from the start, for all 7bn miles of Rosetta’s epic journey, and one of the best, The Planetary Society’s Emily Lakdawalla, has illustrated her latest excellent blog post with a brilliant image showing how big Comet 67P is compared to the comets visited by other spacecraft in the past. Here it is…

20140731_comets_sc_0-000-020_2014

Image credits: Halley: Russian Academy of Sciences / Ted Stryk. Borrelly: NASA / JPL / Ted Stryk. Tempel 1 and Hartley 2: NASA / JPL / UMD. Churyumov-Gerasimenko: ESA / Rosetta / MPS for OSIRIS Team MPS / UPD / LAM / IAA / SSO / INTA / UPM / DASP / IDA. Wild 2: NASA / JPL. Montage by Emily Lakdawalla.

 

Now, if you look carefully at that image something very interesting jumps out at you… of the seven comets now visited, photographed and studied by spacecraft, four appear to be “binary objects” like 67P. What does that mean? What’s its significance? Well, that’s one of the questions Rosetta will be trying to answer. But might it mean that collisions between comet nuclei are – or were, once – common “out there”?

As I’ve been writing this today’s navcam image has been posted online, and yes, detail is definitely appearing on the nucleus…

navcam july 31st

Wow! That’s a big improvement on yesterday’s! And with just a little bit of good-natured amateur enhancing, this is what appears…

navcam july 31st b

We now have several days worth of images to compare, and it seems to me that we can now start to be reasonably confident about some of the features on those images being real and not just imaging artefacts. Maybe. Perhaps.

31 labels

Then again they might all just be artefacts, I don’t know. But, you see, this is EXACTLY why we’d love to be able to see more of the OSIRIS images! Not so we can scoop scientists to their discoveries – seriously, give me a break! – but so we can share their thrill of discovery as new features swim into view. That’s one of the most exciting parts of any mission.

From now on the navcam images of the nucleus of comet 67P should show more and more detail, and we will start to be able to map the nucleus’s surface features, at least roughly. Just think about that. After a journey of almost 7bn miles, lasting almost a decade, a probe called Rosetta is closing in on a comet, a body just a few miles across, little more than a mote of dust compared to the size of the solar system, and soon we’ll be close enough to be able to map it. Isn’t that fantastic?

 

 

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One Response

  1. […] Oben der Kern gestern aus 1327 km Distanz (welche Details auch immer man schon glaubt), auch noch ein Kommentar, ein OSIRIS-PI-IV (mit bemerkenswertem erstem Kommentar und Widersprüchen zu einem früheren) und […]

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