ESA’s Rosetta mission is again teaching us about what happens on comets! The latest science was published in Nature this week, and shows that pits on a comets surface are generated by sinkholes that eject jets of material! Super cool!![tweet https://twitter.com/ESA_Rosetta/status/616291712152039425]
The ESA Rosetta mission to land a spacecraft on a comet has moved into new territory, as the Philae Lander on the comet has woken up after months of having no power! Previous posts on the ESA Rosetta mission here!
Hello Earth! Can you hear me? #WakeUpPhilae—
Philae Lander (@Philae2014) June 14, 2015
Philae Lander (@Philae2014) June 14, 2015
Philae Lander (@Philae2014) June 14, 2015
Science has a special issue this week with the first published data from the ESA Rosetta mission! Check out the introduction to the special issue with a great synopsis of the papers and the Rosetta mission science completed thus far. The rest of the reports and articles can be found here.
Rosetta is uniquely positioned to further the understanding of these primitive bodies, having revealed an unusual and fascinating object. After rendezvous, the Rosetta spacecraft moved from 100 km above the comet to a bound orbit only ~10 km away. This early period of the mission has revealed previously unseen details of a comet nucleus, as Rosetta’s instruments recorded measurements that were once impossible. This issue of Science contains the first published scientific results from Rosetta at comet 67P.
See all the previous CauseScience posts on ESA’s Rosetta Mission and Philae Lander here!
Those people paying close attention may recognize the first author on the introduction, Matt Taylor, who caused quite a stir during the Philae landing.
Explainer: what Philae did in its 60 hours on Comet 67P
By Mark Lorch, University of Hull
The drama of Philae’s slow fall, bounce and unfortunate slide into hibernation was one of the most thrilling science stories of a generation. But what in its short 60 hours of life on Comet 67P did it achieve?
The short answer is analytical chemistry.
Philae’s payload included three instruments that are quite common in chemistry labs, but when deployed on a comet could answer questions about the origins of the solar system and life itself.
Right- or left-handed life
Four billion years ago the solar system was an unsettled place. Earth was undergoing heavy bombardment by asteroids and comets. This continuous shower may have delivered a significant amount of water to our planet. But the comets weren’t just dirty snowballs. A third of their contents was probably complex organic (that is, carbon-based) molecules. These compounds may well have triggered the chemistry that led to life on our planet.
One of Philae’s goals is to provide evidence that the organic chemicals on a comet are sufficiently similar to the building blocks of life to support the comet impact theory for abiogenesis. A key factor is whether Comet 67P (and by extension other comets) contain predominantly right- or left-handed molecules.
Many molecules come in one of two forms, known as stereoisomers, which chemists designate as left- or right-handed. These two forms are identical apart from the fact that they are mirror images of each other.
Your hands are a perfect analogy. Structurally, they are the same except for the fact that you can’t superimpose one on the other. And so it is with stereoisomers.
Strangely, life on Earth is based entirely on left-handed molecules. It is perfectly possible to make the right-handed versions, but life just doesn’t. Where this preference for left-handedness comes from is a mystery. One theory is that the bias came from within the chemistry of comets. In the comets, right-handed molecules may have been preferentially destroyed by a combination of sunlight (to provide energy to trigger chemical reactions) and liquid water (with which the organic compounds could react).
Philae’s COSAC instrument is designed to sniff away at the comet’s organic contents and figure out whether they look like the building blocks of life and, importantly, whether the comet contains the same preference for lefty chemistry as Earth-bound life.
Homegrown detritus or alien debris
Most theories hold that comets were formed from the same nebula that gave birth to rest of the solar system. But this need not be the case. It could be that they are truly ancient bodies that entirely, or in part, pre-date the solar system, or perhaps they have congregated here much more recently? Philae’s Ptolemy instrument aims to answer this question by comparing the ratios of different isotopes within Comet 67P.
A given element is defined by the number of protons in its nucleus. For example carbon always has six protons. However the number of neutrons can vary giving rise to carbon-12 (six protons and six neutrons), carbon-13 (with seven neutrons) and carbon-14 (with eight neutrons). All these different variations are known as isotopes. The ratio of these isotopes in any given body will vary depending on its origins. And since the material in the solar system came from more or less the same place, the isotopic carbon ratios for the Sun, the Earth and asteroids are pretty much the same.
But comets might be different, in fact remote measurements of comet Hale-Boop suggest that it may be an extra-solar alien. The problem is there were large uncertainties in these readings, so we can’t be sure of their accuracy. By sending the Ptolemy instrument to the surface of a comet this should all be resolved, as its isotopic measurements are meant to be as accurate as those performed on Earth, and the solar or alien origins of Comet 67P can be confirmed.
The snowball factories
If comets came from the same stock as the rest of the solar system where and how were they produced? The Hubble telescope spotted comets in the Kuiper belt just beyond Neptune, meanwhile the Oort Cloud (another 10,000 times further away) is thought to contain icy bodies that may, paradoxically, have condensed nearer to Jupiter and Saturn.
Figuring out where 67P may have originated is the job of APXS, an instrument designed to determine the elemental composition of dusty parts of the comet. By comparing this to material on Earth, the origins of which we are more confident about, we should be able to figure out the birth place of 67P.
Mark Lorch does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.
Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
These incredible images show the breathtaking journey of Rosetta’s Philae lander as it approached and then rebounded from its first touchdown on Comet 67P/Churyumov–Gerasimenko on 12 November 2014.
The mosaic comprises a series of images captured by Rosetta’s OSIRIS camera over a 30 minute period spanning the first touchdown. The time of each of image is marked on the corresponding insets and is in GMT. A comparison of the touchdown area shortly before and after first contact with the surface is also provided.
GO AND WATCH THIS xkcd cartoon flip book from yesterday’s comet landing! NOW!! It is informative, adorable, cute, hilarious, exciting, and more!!
Today I posted that the European Space Agency’s landing of Philae on Comet 67P made science history. But, I was wrong. The Philae Lander and Rosetta Spacecraft Mission has made history for HUMANKIND!!! The Philae lander is a huge step forward for space technology and science! It is also just plain exciting!
ESA (@esa) November 12, 2014
One of the coolest parts about the ESA Rosetta Mission, is that the team of scientists and engineers in charge of the Comet Landing included WOMEN! Compare this to the team of NASA scientists and engineers that sent astronauts to the moon (JoAnn Hardin Morgan was the single woman engineer at NASA during Apollo 11). However, the Rosetta Mission is not the first time women have contributed to amazing things in space. Check out Beverly Wettenstein’s long list of incredible contributions women have made in space!
The ESA Rosetta Mission included at least four women who are listed as team members, but I would guess there are many more who contributed but are not listed!
It takes hundreds of people — machinists, engineers, scientists, and many others — to get a spacecraft from the planning stages to its destination in outer space. The people in this gallery represent just a few of the folks who make space exploration ideas a reality.
Let’s celebrate Claudia Alexander (U.S. Rosetta Project Scientist), Margaret Frerking (Co-I with MIRO instrument), Lori Feaga, (ALICE Co-I with University of Maryland), Marilia Samara (ScRI, EIS instrument), and the many other women who contributed to the Rosetta Mission. CauseScience applauds all of these women for their amazing success today, and over the last decade of the mission. These women are the best at what they do, and break down barriers for girls and women in Science, Technology, Engineering, and Math!! CONGRATS!!
Max Mutchler (@maxmutchler) November 12, 2014
ConneXions (@ConneXionsGCI) November 12, 2014
Please inform CauseScience if you know other women that were part of ESA’s Rosetta Mission so we can add their names!
Add Professor Monica Grady to the list of Rosetta women!!
You may have read about shirtgate, and how Rosetta Project Scientist Matt Taylor has been ridiculed on twitter for his sexist and embarassing choice of clothing. While it is certainly important to draw attention to his harmful behavior, celebrating the amazing women that contributed to the history of HUMANKIND is much more important!!