from the when-can-I-view-these-on-google-maps? dept.
http://www.jpl.nasa.gov/news/news.php?release=2014-308
Scientists have found that the surface of comet 67P/Churyumov-Gerasimenko—the target of study for the European Space Agency's Rosetta mission—can be divided into several regions, each characterized by different classes of features. High-resolution images of the comet reveal a unique, multifaceted world.
ESA's Rosetta spacecraft arrived at its destination about a month ago and is currently accompanying the comet as it progresses on its route toward the inner solar system. Scientists have analyzed images of the comet's surface taken by OSIRIS, Rosetta's scientific imaging system, and defined several different regions, each of which has a distinctive physical appearance. This analysis provides the basis for a detailed scientific description of 67P's surface. A map showing the comet's various regions is available at: http://go.nasa.gov/1pU26L2
The new comet maps will offer valuable insights for members of the Rosetta team, who are gathering in Toulouse, France, on September 13 and 14, to determine a primary and backup landing site from five candidates they previously had selected.
For background, see: Rosetta: Landing Site Search Narrows which was published on August 25, 2014:
The European Space Agency's Rosetta mission has chosen five candidate landing sites on comet 67P/Churyumov-Gerasimenko for its Philae lander. Philae's descent to the comet's nucleus, scheduled for this November, will be the first such landing ever attempted. Rosetta is an international mission spearheaded by the European Space Agency with support and instruments provided by NASA.
Choosing the right landing site is a complex process. It must balance the technical needs of the orbiter and lander during all phases of the separation, descent and landing, and during operations on the surface, with the scientific requirements of the 10 instruments on board Philae. A key issue is that uncertainties in navigating the orbiter close to the comet mean that it is possible to specify any given landing zone only in terms of an ellipse—covering about-four-tenths of a square mile (one square kilometer)—within which Philae might land.
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As the Rosetta lander approaches its target comet for a landing in November there are a series of pictures available, and these images have been postprocessed to highlight jets from the comet.
The Rosetta Space Probe is a European Space Agency mission to land a probe on the comet 67P/Churyumov-Gerasimenko. The pictures are taken from Rosetta's Navigation Camera (NAVCAM) at a distance of 28.6 kilometers as it closes in on the comet ahead of the scheduled descent of the Philae lander.
This particular image is an example of the ESA releasing detailed mosaic images for amateurs to process, which started a few weeks ago, and continues to provide some stunning NAVCAM images.
The raw images were released on the ESA blog and there's a summary of the mission objectives available.
Rosetta has been covered previously on Soylent at arrival and mapping of 67P.
A quick note to mention that the ESA have announced that:
The European Space Agency’s Rosetta mission will deploy its lander, Philae, to the surface of Comet 67P/Churyumov–Gerasimenko on 12 November 2014.
There is a Press Release with more details available. For additional background on the Rosetta probe, there have been Soylent stories on the Probe's wakeup from hibernation, arrival at 67P, mapping the comet and camera images.
For more information see the ESA Rosetta Page.
Traveling around space can be hard and require a lot of fuel, which is part of the reason NASA has a spacecraft concept that would hitch a free ride on one of the many comets and asteroids speeding around our solar system at 22,000 miles per hour (on the slow end). Comet Hitchhiker, developed at NASA's Jet Propulsion Laboratory, would feature a reusable tether system to replace the need for propellant for entering orbit and landing on objects.
The spacecraft would first cast an extendable tether toward the object and attach itself using a harpoon attached to the tether. Next, it would reel out the tether while applying a brake that harvests energy while the spacecraft accelerates. This allows Comet Hitchhiker to accelerate and slowly match the speed of its ride, and keeping that slight tension on the line harvests energy that is stored on-board for later use, reeling itself down to the surface of the comet or asteroid. A comet hitchhiker spacecraft can obtain up to ~10 km/s of delta-V by using a carbon nanotube (CNT) tether, reaching the current orbital distance of Pluto (32.6 AU) in just 5.6 years.
Unfortunately rocket scientists apparently don't read SN, or they'd know from discussions last year that it simply won't work. It seems that the idea defies "basic orbital mechanics" and "makes no sense".
Original Submission
(Score: 4, Interesting) by TGV on Saturday September 13 2014, @03:23PM
I've got nothing to add, but I find this a fantastic enterprise: a satellite is orbiting a comet. It was cool at the start, but now that they actually have got it in orbit, I'm impressed. If they can actually land a probe, I will be deeply impressed.
(Score: 2) by evilviper on Sunday September 14 2014, @01:20AM
I'd really like to see a space agency "lassoing" a long-periodic comet... using it as a free ride to a very distant perihelion, then using it as a springboard to push off of, into inter-stellar space, and in the direction of the nearest solar system.
Even after many decades of the "space age", we are still completely ignorant of, say, information about any planets outside our solar system. Flinging a sensor package off a comet, then going full-bore towards Alpha Centuri, would give us the opportunity to expand our horizon, and actually get better and better data on whats out there, as the craft gets ever-nearer to our stellar neighbors.
Want to get people excited about space? A fuzzy distant photograph of a planet in another solar system would sure do it, and for less than the cost of a manned Mars mission, which won't really add much to our scientific knowledge.
Hydrogen cyanide is a delicious and necessary part of the human diet.
(Score: 1, Informative) by Anonymous Coward on Sunday September 14 2014, @04:52AM
If you can match speed with a comet, you could enter its orbit, with or without the comet: they don't give you any useful ride.
If you latch onto a comment and wait until its far out, if you let go, you will fall along its orbit, and keep following it: it won't help you launch anywhere.
We have a couple of space craft heading out of the solar system already. Comets by definition are at less than escape velocity. We have already done much better than a ride on a comet can ever do.
Consider learning basic orbital mechanics: all points on an orbit are energetically equivalent. This is trivially derived from conservation of energy. Your post makes no sense.
(Score: 2) by aristarchus on Sunday September 14 2014, @07:56AM
Sometimes, just going along for the ride is enough. Fair skies, Philae, and I hope you don't get fried in perihelion.
(Score: 2) by evilviper on Sunday September 14 2014, @06:49PM
That's what the lasso is for... Some kind of very long cable on a winch to let the comet pull the craft, with lots of slack so to smooth out the sudden change in momentum.
Having a solid and massive surface behind your craft, to push away from, can give you more of a boost than just firing rockets. You could do without it, but it's a beneficial option to have available.
"Single-apparition or [non-periodic] comets are those with a hyperbolic or parabolic osculating, which makes them permanently exit the Solar System after a single pass of the Sun."
Utter nonsense!
Voyager I is at 128.26 AU.
"Long-period comets such as Comet West and C/1999 F1 can have apoapsis distances of nearly 70,000 AU"
https://en.wikipedia.org/wiki/Long-period_comet#Long_period [wikipedia.org]
Your response is a combination of complete misunderstandings of my idea, as well as some some horrible misconceptions about space of your own.
Hydrogen cyanide is a delicious and necessary part of the human diet.