Should NASA be thinking about sending a manned mission to an asteroid?
This isn’t as silly as it might sound. A major factor in landing on another object in space is what is called "delta-v" — literally the difference in velocities of the two objects. Everything is moving, and if you leave a moving object — oh, say, the Earth — and want to land on another, you have to change your velocity enough to zero out the differences in your velocities. That means burning fuel, and that’s a precious commodity.
So the best targets are ones that have very little delta-v from the Earth, and many asteroids fit the bill. They may be on similar orbits to the Earth, or there may be one part of the orbit where the asteroid is moving relatively slowly compared to the Earth. So in fact, getting to some asteroids may be easier than getting to the Moon, even if it means a longer trip!
MY old friend Dan Durda, who knows his stuff about such things, was recently interviewed on an Oklahoma TV station about this topic and as usual does a great job talking about it.
As far as a timetable goes… I wonder. We have to wait for the Orion rockets to be able to do this, and the Moon looms large in NASA’s schedule. But I think slipping something like this in the docket is just what NASA should be doing. And we may see it happen around the same time we go back to the Moon.
February 9th, 2007 at 11:27 am
I just hope no one ends up on the terrible ASTEROID OF THE APES!!!
Here’s an excerpt from the movie:
Taylor: “Dodge! Read the atmosphere!”
Dodge: “What atmosphere!? This rock’s only two miles across!”
February 9th, 2007 at 11:45 am
[…] “A manned spaceflight to an asteroid“, no Bad Astronomy; […]
February 9th, 2007 at 12:00 pm
Ah, I can see Hoagland saying that this is how we’ll find & hide the evidence for the long-lost civilization that created antigravity & destroyed the planet between Mars & Jupiter, thus creating the asteroid belt in the first place!
Or ignorant masses of people worrying about how this mission will cause an asteroid to hit Earth, and NASA, being omnipotent and all, will hide the fact from the public, because we all know that in order to rule the world, the world has to be destroyed first.
Man, even bad movies have better thought-out plots than those two scenarios. Why DO people believe strange things?
Anyway, the asteroid mission sounds kind of cool, and certainly do-able from a technology standpoint. But will the public be behind it? (I personally hope so, but I won’t hold my breath!)
February 9th, 2007 at 12:11 pm
Is this a job for a solar sail test?
Or maybe I just want to hear astronauts using more nautical terms.
NASA: You’re sailing a little close to the wind.
Probe: We’re close hauled along a lee shore.
NASA: Don’t get pooped.
Probe: She should fetch back her destination in a couple tacks.
NASA: You want to overhaul the buntlines?
Probe: No, but I told you we should have Bermuda rigged this thing.
February 9th, 2007 at 12:12 pm
Part of the problem NASA has these days capturing the public’s imagination - besides having love-crazed astronauts ride cross-country in diapers - is the fact that since 1969, we’re been going where man HAS gone before.
An asteroid mission - where man has NOT gone before - will do much more for the public’s fascination with space than even a return trip to the Moon.
February 9th, 2007 at 12:31 pm
I’d go. In a heartbeat.
Of course, what would the purposes be of humans traveling to an asteroid?
* Testing various flight technologies?
* Testing various landing equipment?
* Searching for water or rare minerals?
* Because its there?
I have to say, there is definitely something significant about a human actually running his or her fingers thru the soil of another planetary body, as compared to a cold robitic arm. As long as Bruce Willis isn’t on the crew list, I am all for it!
February 9th, 2007 at 12:46 pm
Ok, Landing a man on a asteroid, Why? Machine not good enough for you?
If we pick a small enough of an asteroid the sheer fact of bumping it from landing on it will change it’s orbit ever so slightly. Then in a couple hundred years, here it comes on a collision course with us (Earth) returning the favor of a visit.
The odd of this occurring are of course astronomical but you know the woowoos will be out thick on this one.
Who calculates the new orbit of the target asteroid after we have landed and taken-off again?
February 9th, 2007 at 12:48 pm
The BA says:
“…getting to some asteroids may be easier than getting to the Moon”
But, JFK said,
“We choose to go to the Moon, and to do the other things, not because they are easy, but because they are hard.”
February 9th, 2007 at 1:05 pm
Capt. Action Says:
“The odd of this occurring are of course astronomical but you know the woowoos will be out thick on this one.”
This reminds me of about a year and a half ago, when the impactor was about to slam into that comet. There was a typical alarmist on Usenet, wailing about the potential for the comet to be knocked off course- STRAIGHT FOR EARTH. I clearly recall this poster saying, “I just wish I could be there [Mission Control] when it goes terribly wrong.” It was funny.
“Who calculates the new orbit of the target asteroid after we have landed and taken-off again?”
That ought to be easily calculable, knowing the interaction between the asteroid & spacecraft. It’d undoubtedly be no more severe than perturbations due to the Yarkovsky Effect.
February 9th, 2007 at 1:16 pm
I never thought about sending people to one of the asteroids, but…why not? That sounds like a pretty good idea to me! Not much science in it, but that could be a great interest-gatherer for NASA.
February 9th, 2007 at 1:17 pm
How about 99942 Apophis? Can’t take much energy to get THERE…
February 9th, 2007 at 3:09 pm
The best thing about getting people to an asteroid is that it could eventually pave the way for asteroid mining operations.
Ben Bova would be thrilled!
February 9th, 2007 at 3:12 pm
Should NASA be thinking about sending a manned mission to an asteroid?
Definitely. Asteroids are much more useful than Moon what comes to minerals. In addition, it doesn’t hurt to learn to deflect potentially dangerous ones.
If we seriously want to learn to live in space, asteroids should be considered potential targets for settlement. There are several unknowns, however. For example, it is not known if there many monolithic asteroids or are all more or less porous rubble piles held together by their own gravity.
It could be relatively easy to make a monolithic asteroid livable: just carve it up and put it spinning in order to create artificial gravity. Pump in air collected from cometary/asteroidal oxygen and nitrogen. Radiation, a deadly danger to a spacefaring civilizations is solved by the thick layer of rock.
All necessary materials (rock, metals, carbon, water, air) are relatively easy to collect; there are more than plenty of energy available if the surface of the asteroid is coated with solar panels. Modern solar planets work well even at the distance of Jupiter. Deep gravity wells are not a problem, which saves a lot of fuel and allows more lightweight spaceship design.
I don’t think it is unlikely that asteroid belt is populated before the Moon or Mars.
Question is, what we are waiting for!?
February 9th, 2007 at 3:56 pm
If we pick a small enough of an asteroid the sheer fact of bumping it from landing on it will change it’s orbit ever so slightly. Then in a couple hundred years, here it comes on a collision course with us (Earth) returning the favor of a visit.
For an asteroid that does not already cross Earth’s orbit, that would only be possible for an asteroid lighter than whatever vehicle lands on it. Think of it this way: a rocket is going to expend only the enough energy to give it the minimum change in velocity that puts it into an Earth crossing orbit. Worst case, all that change in momentum is imparted into the asteroid (requiring all the rocket exhaust to hit the asteroid, which is never going to be the case with realistic rockets). By conservation of momentum, if the asteroid is heavier than the rocket, its change in velocity is going to be smaller than the rocket’s, meaning it will not have a sufficient change in velocity to attain an Earth crossing orbit.
On the other hand, if the asteroid is already on an Earth crossing orbit, perturbing that orbit is just as likely to postpone the inevitable collision as it is to make it happen sooner.
February 9th, 2007 at 4:03 pm
If we can land on one of those metal rich asteroids, then imagine the possibilities. Mining an asteroid will come to closer to reality.
Phil, didn’t you once write in your book that trillions of dollars worth of pure metal can come from an asteroid?
I read on Wiki that Apollo once had a manned flyby of Venus planned. I’m willing to bet that with Orion might take up on those old missions.
February 9th, 2007 at 4:25 pm
How about a fisking of politically driven bad space science? I am thinking mainly of scientific “policy” based on bad fifties scifi. I am thinking now of the mirrors and soot “plans” to deal with global warming, but the arbitrary unfunded Mars manned mission decree, the refusal to negotiate space weapons treaties and the recent Chinese demonstration of a kinetic kill attack, the SDI, many imposed NASA funding and mission decisions, etc. are all fodder.
February 9th, 2007 at 4:26 pm
It was thought that the so-called M-type asteroids consist of pure iron-nickel, but now it seems that it is not the case.
Still, there are many iron-nickel asteroids that must have come from metallic asteroids.
February 9th, 2007 at 4:42 pm
I’ve been an advocate of this for a long time. When ‘W’ announced the return to the Moon I realized hey this same hardware can get us to an asteroid. It would be a strange wonderful mission. The entire body could be explored. One problem dust! Any stirred up will take 15 minutes or more to return to the surface and the astroNOTS would weigh about the same as a handfull of paperclips!
Asteroids have a lot of possible future uses, unlike the moon. They can be mined, they could be a truly amazing tourist experience. A hollowed out asteroid could allow for human powered flight, strap on some wings and flap! Unlike the moon you’re more likely to find a good mix of materials. Of course any practical knowledge would be useful in the case one needs to be diverted (as well as the hardware to get to one and quickly to move one out of harms way. An asteroid mission is a longer flight but less energy an excellent goal midway between the 3 day cake walk to the moon and the 3 month odyssey to mars. As far as tunneling goes any new settlers could probably bore through the entire body. The center might well have some pretty hefty gravity (any body have any idea how much?) I don’t think it would approach earth or moon gravity though.
February 9th, 2007 at 6:59 pm
Good piece. The interviewees did well, and, probably more importantly, the reporter and editor put things together coherently.
I’ve been researching these missions for a project, and they are intriguing, however, there’s a very narrow group of objects for which the delta-v to visit them is not BIG. Inclination is a big factor, and any eccentricity in the orbit means you’ve got to apply a lot of thrust to follow the rock for a while. The few that don’t require a lot of delta-v are in such close synchronization with Earth that you have to wait YEARS for a proper line-up.
Also, the 60-90 day mission length is a tough sell. Possible, assuming the patience to wait or more discoveries, but most ‘close approaches’ of the asteroids we know of now are still ~1-2Mkm away. That’s on the order of weeks of flight time one way. You can cut it down but again, you’re burning propellants and you’ll just need to counteract the additional speed anyway.
I’m hoping I’m wrong in my calculations. Anyone who wants to talk about it please email me from my website.
February 9th, 2007 at 7:59 pm
I proposed this very thing right here on the BA Blog about 6 months ago. Dibs on the window seat!
February 9th, 2007 at 11:15 pm
To me, the real question is not whether it is easy to send a man to an asteroid, but whether it is necessary. What would he (or she!) be doing there that an unmanned probe cannot, and that will justify the extra expense? For the cost of every manned mission of any sort, we can finance probably dozens of unmanned ones. This alone should make us skeptical to any proposals for manned space expeditions, unless in that one manned expedition, they will be doing more science than the dozen unmanned ones would have been able to do.
And not to be overly cynical, but I think the only reason why George Bush is even aware of the moon’s existence is because the Chinese have plans in the works to send someone there. I think he doesn’t want them to take all of it, so he wants to get there first. Of course, he probably thinks the moon is a place somewhere in Mexico.
February 10th, 2007 at 5:12 am
Well, we may have a new record of 21 postings before our current president got mentioned in a non-flattering light.
Asking why send people is perfectly valid, and if your goal is basic composition studies, photo-spectroscopy, and perhaps a sample return, then Brian’s statements about robotic missions are correct. Spirit and Opportunity have done incredible things on Mars, but their principal investigator, Steve Squyres, stated that a crewed mission could do all that they’ve done and more in just a couple days. In-depth science, able to alter its methods moment-to-moment based on new discoveries, requires people on the scene with the right equipment. Mining is also people-intensive, though less so on Earth than it’s been in the past. Colonization, which I hope comes to pass, is by definition a human endeavor.
To me, it boils down to this: If our purpose is to write scientific papers, then robots are the way to go. If we want to do more, people have to be there.
February 10th, 2007 at 8:31 am
Troy: Gravitational acceleration decreases as one approaches from the surface to a bodies center, ergo, there would be NO “gravity” at the center of an asteroid.
Which is what makes all the material resources of such small bodies accessible.
If you want to know what can be done with asteroid resources, read Dr. Gerard K. O’Neilles book, The High frontier.
Gary 7
February 10th, 2007 at 10:33 am
are there any currently known candidates for this mission? i understand that by the time the mission could be run there will likely be hundreds more discovered, but what objects are reachable now?
also, i’m imagining bearded hillbilly astronauts staking claims on prime asteroids, living in abandoned mines, waving their bird-guns at passing spacecraft - “git offa my propitty!”
February 10th, 2007 at 10:37 am
What’s the effect of actually hollowing out the insides of an Asteroid. It seems to me that all that mass raised to the surface and exported would change the orbit and, in fact, the little gravity it had.
What is the effect of the rocket powered freight vessel leaving the asteroid? And the many such trips that would be needed to effectively exhaust that source of minerals or whatever?
As a closing ceremony, would someone ‘pull the plug’, and collapse the shell to a much smaller ‘oid, or instead, even tow it back to Earth to be exhibited in a museum, or even go on a world tour?
February 10th, 2007 at 1:51 pm
NASA has to take a manned trip to the bank before they can afford to buy so many future missions.
February 10th, 2007 at 3:15 pm
To me, the real question is not whether it is easy to send a man to an asteroid, but whether it is necessary. What would he (or she!) be doing there that an unmanned probe cannot, and that will justify the extra expense?
You can’t learn to life in space and to colonize the Solar System using only robots…
Otherwise, of course, robots are superior in almost every way. With the future advanced robotics and artificial intelligence you can scrub the word ‘almost’.
Why colonize space? Because otherwise our species will face a certain extinction, sooner or later. It’s that simple.
February 11th, 2007 at 12:50 pm
As to candidates with a low delta-v requirement, my best find so far is 1991 VG. Unfortunately the nice, slow close approach doesn’t happen until 20 Nov 2068. On the bright side, the astronauts could celebrate the 100th anniversary of Apollo 8 on their trip…
You can see what a plot of it looks like by going to this website:
http://neo.jpl.nasa.gov/orbits/
and searching for 1991 VG
February 11th, 2007 at 2:27 pm
One of the best arguments (apart from the simple fact that increasing knowledge is always good) that I read for this was that it would actually fit in easily in the series of testlaunches that will no doubt happen for the new hardware. According to the guy it was a relatively easy mission to build, based on an earth orbit test flight. Getting science data from a testflight, and a fantastic publicity bonus too.. perfect
Can’t find it anymore so unfortunately I can’t give a link.
February 12th, 2007 at 9:45 am
I realized one thing; the astronauts will certainly need to watch their step.
On such a small body, one could inadvertinly leap right off the surface! Oops.
June 27th, 2007 at 2:42 am
Turbocharge Space exploration, if they start a metal industri into space into a astroid it would denfenetly spice up things, and make manned missions to other planets in ower solarsystem easyer.
But ill guess the moon aint bad either, but after all after the astroid is mined, it would definetly be suitable for living in. And makeing it self a suitable big “bus”, to other planets, if they want many people at once to move this would be a way to do it.