WISE Discovers 95 New Near-Earth Asteroids 112
astroengine writes "NASA's Wide-Field Infrared Survey Explorer (WISE) has turned up 25,000 new asteroid discoveries, 95 of which are near-Earth objects (NEOs). This mission is as fascinating as it is frightening. Capable of spotting any cosmic object glowing in infrared wavelengths, WISE has become an expert asteroid hunter, seeing these interplanetary vagabonds, some of which get uncomfortably close to our planet."
Re:A WISE old owl? (Score:3, Interesting)
Hey Slashdot! (Score:4, Interesting)
The question is... (Score:3, Interesting)
The question is, would they tell us -- the general public -- if any of them were a real threat?
Some NEOs also head out to Mars and the Asteroids (Score:5, Interesting)
Maybe if we want to get a probe out that way it could hitch a ride - and keep an eye on its dangerous companion as well.
While we're at it, Ceres is a nice asteroid to visit. It will be in a good spot in four years. It's likely completely covered with ice, could have liquid water, and has a nice low escape velocity - especially when you consider the rotational boost at the equator. Why, it's got a lot of the stuff you would be looking for in a fuel depot in the asteroid belt as a gateway to the stars. If Obama wants to visit Asteroids, let me recommend the biggest one.
I think if I was writing sci-fi I'd put habitation rings on the poles of Ceres and then accelerate them until they had a comfortable .5G or so on the perimeter. Probably counter-rotate the rings and tunnel through the planetoid from axis to axis. Nuclear power of course. Access through the Axis where it's close to 0G. An AI controlled water-based auto gyro-balancing mechanism can correct for people and stuff moving about on the wheels and hosing up the gyro. Asteroid mining ships wouldn't dock, they're too big. They'd get their water and provisions by scheduling an intercept vector. Launching would be a matter of pumping water to the right spot on the equator, embedding potables and manufactured goods and trackers and letting it freeze and then letting it out on a tether until it had even more rotational velocity and letting it go at the right moment. On Ceres the space elevator idea works well. Maybe snow-coat the package for impact absorption and target an asteroid close to the miner far off in the belt. Trade for fissionables and high grade ore - just launch the package into a Ceres intercept vector tagged with an invoice number and minimal course-correction waldos for close approach control.
Asteroid miners could visit on shuttles though - land on the equator, hop a local shuttle and enter through the Axis, or better yet - an elevator to the Core habitat with tunnels to the poles. Maybe I'd spin the core habitat too, and land the elevator just off it. With a surface gravity of 0.02G, the core pressure can't be too high for a habitat that's well armored by the mass of the planetoid. The equator gives a nice rotational vector for liftoff, reducing escape delta-v by almost 1/4. It's a great spot for a spaceport and colony - except for the long winters of course. Probably some cultural differences between Ringers and Grounders on Ceres to build a story around, lots of caves to explore to work in an ET angle. With 2.6 million square kilometers of surface area maybe some real-estate issues. A few billion years ago it was quite a lot warmer out this far, as the Sun was much brighter, so the alien relics can represent species more like us. Lots of ice to take cores of and find evidence of panspermia for the stories.
While we're at it, let's have asteroid miners drop laser reflectors and/or radar transponders on the largest asteroids they visit - that just happen to illuminate much of the belt in a way that facilitates object tracking.
Ceres is too rock-active for an interstellar spaceport and starship shipwright. For that you need a low-G environment near a planet that's swept its orbit so I would put that on Phobos probably.
There are lots of rocks out there. Impacts have to be fairly frequent too for added drama. It's likely by now the dust-to-pea sized stuff is well collected by now into larger asteroids so it's just the Walnut-to-city sized stuff to worry about. I wonder if anybody's calculated asteroid intercepts for Ceres yet. Ceres has had a long time to intercept the easy targets, just as Earth has, but there are a lot more rocks in that neighborhood than ours.
Re:The next step (Score:5, Interesting)
Its pretty easy to move something bigger, given enough time. Potential mitigation of Apophis, among other asteroids, has been extensively studied. Note that its approximately 270 meters and 2.7e10 kg, enough to cause significant regional destruction, wiping out a continent.
As an example case study that I worked on, a 500 kg spacecraft hovering a few hundred meters away from an asteroid for a year is enough to move it 10s of Earth radii. Note that you'd need similar behavior to get a good track. The key is to make the move early. This particular plan was intended to eliminate the threat of a 2036 impact, which is well known to correspond with a 600-meter wide 'keyhole' during the 2029 approach. By moving the asteroid a few meters forward or backwards in 2022, the threat is mitigated -- you move it by kilometers and in 2029, and 10s of Earth radii in 2036.
Closed orbits over many revolutions are incredibly sensitive to very small changes, and close flybys, which are likely for a potential threat, increase the sensitivity by orders of magnitude. The key ingredients are time, tracking, and high fidelity trajectory models.
Re:This isn't scary at all (Score:3, Interesting)
Nope according to quantum theory they didn't exist before because we couldn't measure them. Or was that intelligent design? I always get the two confused. Both require the belief that in the beginning there was nothing and then it exploded.
Ah, but in quantum mechanics, once we observe something ("cause the the wave function to collapse into a determined state", to be technical), we retroactively determine it's existence at least as far back from the observation as uncertainty principle allows us to theoretically calculate.
So even if an asteroid doesn't exist now, if we observe it as a fiery ball hurtling across the sky and getting rapidly bigger, it's existence will get retroactively established back through the history of the universe.
The only protection is to observe that an asteroid is not in a certain location, and thus snuff out the possibility of one popping up there magically just to annoy (and kill) us. Once we have observed all possible locations where a rogue asteroid could be, we can be sure none will pop out of nothingness.
Or alternatively, if you think magically appearing asteroids are not a plausible idea, you can think the asteroid was there all the time, but that's boring... ;-)