Hello all,
Arie asked me for an update, so here it is!
We have just passed a major mission milestone, over two years at the comet! A nice way to celebrate that was the rendering of the orbit around the comet since July 2014.
http://blogs.esa.int/rosetta/2016/08/05/celebrating-two-years-at-the-comet/
We have called it the “spaghetti plot” for obvious reasons (see the image at the top). I have used a similar plot in talks I have given. It shows we have spent a lot of time in the terminator plane (plane separating night side and day side) and a lot of time > 10 km from the comet, all due to the dust environment being so challenging for navigation, as I mentioned previously. So there is lots of work to fill in the gaps using simulations. It also shows the cool fly overs and the excursions too. From all these orbits we have orders of magnitude more data than ever before from a comet, there really is some awesome science to be done.
Some Rosetta papers are now starting to put different data sets together, which is where some of the major science will be done. A highlight was a paper by Björn Davidsson, who has used the various observations, primarily from OSIRIS (and the observation small 1 -3 metre cometessimals all over the comet), to look at viable formation mechanisms for the comet, concluding that Rosetta observations suggest comets were formed slow and late in the solar system and so are primordial, and didn’t get processed much by collisions. http://blogs.esa.int/rosetta/201607/28/how-comets-are-born/ Papers examining the longer term trends are starting to appear, this paper by Gianrico Filacchione and co-authors have shown how the comet surface evolved before the landing in 2014, getting brighter and icier with time (see the image beneath the link). http://blogs.esa.int/rosetta/2016/04/07/the-colour-changing-comet/
We finally saw the publication of the Rosina detection of Glycine on the comet, underpinning the idea that comet have the capability of providing the building blocks of life http://blogs.esa.int/rosetta/2016/05/27/rosettas-comet-contains-ingredients-for-life/ Talking of science, in March this year, we had a very nice science meeting in Leiden. http://sci.esa.int/rosetta/56356-from-giotto-to-rosetta-50th-eslab-symposium/ We discussed the latest results from Rosetta and put them in context with results overall made by cometary missions, but also in the more general astrophysical context, with a very nice talk by very awesome Prof. Ewine Van Dishoeck from Leiden University for example. The papers from that meeting are being put together for a special issue in the Monthly Notices of the Royal astronomical Society, and should be available to download without a fee!!! Stay tuned for that as there are some good updates on the comet, including the fireworks we saw at perihelion and also some of the large outbursts we have seen, including this year, with a paper on an event from 19 February which should feature as an ESA blog post, but i cant link to it at the time of writing this, so go have a look yourself! Here is a selfie from the meeting J, note the Rosetta spacecraft model on the left, and also the wonderful comet inspired art by Ekaterina Smirnova. http://www.ekaterina-smirnova.com In fact the Rosetta mission has inspired a lot of people artistically, so much so that my colleague Claudia Mignone, here at ESTEC, put together a blog post and Tumblr page highlights this all http://blogs.esa.int/rosetta/2016/05/12/artistic-tributes-to-rosetta/There is music also in those pages, and as I had some music in my last post, here is some more- the composer Vangelis has an album coming out inspired by Rosetta!!!http://blogs.esa.int/rosetta/2016/07/29/new-vangelis-album-inspired-by-esas-rosetta-mission/Since October we gradually approached the comet again, to get within 10 km of the surface. We then did a special excursion into the tail region, to examine the plasma interactions there, and got this awesome high phase angle shot (~159 degrees between the spacecraft – comet -sun) http://blogs.esa.int/rosetta/2016/04/01/cometwatch-27-march/ We then did a fly by at 30 km at zero phase angle! http://blogs.esa.int/rosetta/2016/04/15/cometwatch-10-april/ Following this we gradually approached the comet again, getting to within 7 km before carrying out from special elliptical orbits designed to investigate the radial profile of the coma, and then in July- August to move into the end of mission orbit. Which we have started on with an 8 x 13 km ellipse, which takes 3 days to complete and is tilted 20 degrees from the terminator, with the closest approach on the dayside. Every 3 days we will look to get closer on the next orbit. This week 18 021 August we will look to alter the elliptic orbit to get to a 15.1 x 6 km orbit, and dip< 5 km from the surface. This is the final phase of the mission, slowly spiralling closer and closer to the comet, and finally we will impact on 30 September.
So we are getting some of the closest data ever, as I write this, OSIRIS released another nice image (also shown here above): https://planetgate.mps.mpg.de/Image_of_the_Day/public/OSIRIS_IofD_2016-08-18.html We are so close that you cant tell what part of the comet we are looking at !!!In the case of the NAC image from 15 August 2016, it’s the Seth region on the back of the duck, near Anubis, the field of view of the NAC camera for that image is shown in the graphic as a grey square. The Seth region is cool, full of the pits we are interested in when considering the source of some of the activity of the comet.These pits were highlighted in a paper earlier by Jean-Baptiste Vincent, and identified to be the source of some of the jets. http://blogs.esa.int/rosetta/2015/07/01/comet-sinkholes-generate-jets/ This work has been expanded and I there is a nice paper in the MNRAS special issue from ESLAB on this, and there will be a blog post also. These regions are also shown to contain so called “goose bumps”, small 1-3 metre features that are considered to be the building blocks discussed in the Davidsson paper I mentioned above.
Note that ESTEC has an open day again this year (http://www.esa.int/dut/ESA_in_your_country/The_Netherlands/ESTEC_Open_Day_2016_op_2_oktober). It is 2 days after the Rosetta EOM, and I hope to give a talk at ESTEC on Rosetta, rounding up the operational part of the mission.For me, I will have mixed emotions about the end of the operations of Rosetta, personally, things wont be as hectic as the last few years .I will still have lots of work to do making sure we have the best science data in the archives. We still have DECADES of data analysis to do with the data however, there really is a “schatkist” of science there! As I said last time, stay tuned to the Rosetta blog. http://blogs.esa.int/rosetta/
Hi Matt, thanx for the update! We’re all looking forward for the ‘crash’ of Rosetta on 67P on september 30th. Do you think there is a possibility that Rosetta (or parts of it) will survive the crash?
Parts could survive and likely will, but the spacecraft won’t be in good shape, it was designed to “fly” not land. Once we lose contact with the HGA (high gain antenna) that is it, we won’t know anything more about Rosetta.
Until some curious scientist sometime in 2070’s decides he want to take a look and makes a flyby with his spaceship.
Just dreaming. 😉
Kind regards,
Gert (Enceladus)