NASA's Mars Fleet Checks In
All Three NASA Mars Orbiters Healthy After Comet Flyby
“All three NASA orbiters around Mars confirmed their healthy status Sunday after each took shelter behind Mars during a period of risk from dust released by a passing comet. Mars Odyssey, Mars Reconnaissance Orbiter and the Mars Atmosphere and Volatile Evolution (MAVEN) orbiter all are part of a campaign to study comet C/2013 A1 Siding Spring and possible effects on the Martian atmosphere from gases and dust released by the comet. The comet sped past Mars today much closer than any other know comet flyby of a planet.”
– NASA’s Mars Odyssey Orbiter Watches Comet Fly Near
– NASA’s MAVEN Studies Passing Comet and Its Effects
– NASA’s Mars Reconnaissance Orbiter Studies Comet Flyby
I’m always happy to hear about the Mars spacecraft. I just wish we had more around other planets – every planet should have a good orbiter around it.
I agree. Mercury, Venus, Earth, Mars, and Saturn have orbiters. Jupiter will have one again in mid 2016. Ceres and Vesta are sharing an orbiter. Alas, I don’t see even new flybys of Uranus or Neptune (the last in the late 1980’s) with proposed orbiters on budget holds, and Pluto will soon have its only temporary visitor.
And every former planet (Ceres and Pluto having been demoted).
What about Pallas, Juno, and Vesta? They were considered planets for about 40 years along with Ceres, before the discovery of many more asteroids in the late 1840s and 1850s.
It would be interesting to have a sort of super-Dawn probe(s) with serious (or replenishable) propellent reserves for its electric drive , spending decades roaming the asteroid belts, dropping sampler probes. There is a vast array of strange critters out there.
i agree. a Dawn redux that flies by, say, 10 or more asteroids.
Just like we have found that planetary moons are the really exciting stuff – often more than the planet, asteroids are intriguing objects that come in a zoo of varieties.
And beyond just basic research (altho that is reason enough), there is unlimited potential resources and maybe even future colonies.
http://www.nss.org/settleme…
And to give people a sense of scale…
The first compares Itokawa with Orion and ISS. The second contrasts tiny Itokawa with some proper asteroids.
The lifetime of an ion thruster is limited by wear and tear (specifically grid erosion from the keV Xe ion beam.) That’s why Dawn has three thrusters; to run them to death, one after the other. So just tanking up with more Xe wouldn’t be enough.
On the other hand, you don’t necessarily need more delta-v than Dawn to visit a dozen asteroids. Dawn is specifically targeting two of the biggest, and they aren’t exactly on similar orbits. This might make an interesting project for an aerospace engineering student: Given a spacecraft like Dawn, how many asteroids could it orbit? Make it over 100 km radius to be interesting, and you’ve got a mix of low-thrust trajectory optimization and a variation on the traveling salesman problem.
I would choose from a range of diameters, going for what’s interesting. Flybys may have to suffice for some,
With the newer “NEXT” ion engines running for more than 5 1/2 years, my “super-Dawn” with 4 or five of these puppies, and relying on extended coast phases, it should be able to explore for a period stretching maybe to decades.
Adding in some solar sails would also be cool:
http://books.google.com/boo…