Slashdot Mirror
NASA Satellite Snaps First Image of Target Asteroid
coondoggie writes "NASA today said that its Dawn spacecraft snapped the first image of the giant asteroid Vesta it hopes to rendezvous with in July. The asteroid is 530 kilometers in diameter, and appears as a small, bright pearl against a background of stars. Vesta is known as a protoplanet, because it is a large body that almost formed into a planet. It's the second most massive object in the asteroid belt, NASA says."
Come on, Network World for a NASA news release? Ridiculous.
Here is the actual NASA press release.
It's next rendezvous after Vesta is an asteroid called Wendows-7.
This is obviously Photoshop. I mean if it were real we should see a 5% whiter pixel in the top left.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Naw, graphics out to be of something that's a real threat...
http://en.rian.ru/cartoons/20110511/163969086.html
I think my eyes are getting better. Instead of a big dark blur, I see a big bright blur.
The title reads, "NASAsatellite Snaps First Image of Target Asteroid".
Is this a SATELLITE or a SPACECRAFT? If it's not orbiting anything, it's not really a satellite.
And, of course, it's missing a space (no pun intended) between NASA and Satellite.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
Dear Chinese Friends,
You are prohibited from viewing this image.
Thank you,
NASA
I am very small, utmostly microscopic.
Is this a SATELLITE or a SPACECRAFT? If it's not orbiting anything, it's not really a satellite.
It's orbiting the Sun .
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
"I am Princess Vespa, daughter of Roland, King of the Druids!"
Maybe they'll find a space camper on that rock?
Talking about asteroid impacts, this is just a question which had popped up in my head. Just thought this will be the best place to get the answer –
I am not an astronomer. So my question below might contain a lot of factual errors and foolishness. But I had this doubt for a long time, which I wanted to solve.
For avoiding asteroid impact – is the following method thought out and discarded?
Keep a pretty big satellite circling (or nearby) the earth. Make it the fastest man made object – if possible even faster than Solar Probe + , by using gravity assists. Now, suppose we find that an asteroid is going to hit the earth, get this satellite to impact the asteroid and nudge it out of position so that it doesnt hit earth.
The advantage of this option is:
1. The satellite is always on standby – so if it is required, we can use it in a short notice (1 year range)
2. The more the time we have – i.e. if the asteroid is going to hit us in say 50 years, more slingshot runs we could do and due to gravity assists so that we can increase the speed to a very huge value
3. The faster it is, the less mass it need be – say a satellite weighing 10 ton and say moving at 200 km/s should be able to nudge a moderate size asteroid –
Comparison:
Asteroid Diameter: 100 m
Asteroid size: approx 10^6 ton – speed 10 km/s
Satellite: size: approx 10 ton – speed 200 km/s
Energy ratio ~= 250 : 1
If, say, we find the asteroid when it is at around 100 Million kms from earth (at least 6 months prior to collision)
This looks good enough to nudge the asteroid enough to avoid collision – from my non-scientific viewpoint. Am I completely wrong here?
Since we usually find asteroids in such time and distances, what are the pitfalls here?
rajmohan_h@yahoo.com
"Keep a pretty big satellite"
Philip J Fry suggested trash.
. . . here's a low-bandwidth version: o
A large body that almost formed into a planet? Pluto has more than twice the diameter (i.e. eight times the volume) and is still no planet.
Dear Taco, Satellites orbit things, Items on transfer orbits would almost by definition not be a satellite.
Why are chinese not allowed to view, i think that is quite bad.
If it was about the energy ratio, you'd be right, but the energy ratio isn't relevant. Alas, it's about momentum, and momentum scales linearly with velocity. This makes the whole thing impractical. Assuming:
- the satellite's path would intersect the asteroid path at right angle,
- the satellite would embed itself in the asteroid
Then, in SI units, the velocity of the compound object is (10E9*[10E3 0] + 10E3*[0 200E3])/(10E9+10E3) = [9.9999 0.002]*1E3 m/s.
The total system would gain a 2m/s motion component in the direction of the satellite's path. Since Earth is about 12.8E6 m in diameter, it'd take about 6E6 seconds to clear Earth -- that's 70 days
Of course we're ignoring the gravitational pull of Earth, so we'd really have to move the asteroid at least a few Earth diameters out. So half a year is cutting it close I'd say.
Alas, your asteroid mass could be off by a bunch of orders of magnitude. The K-T "dino killer" chondrite is estimated at 10E3m in diameter, and I presume its density is about 3ton/m^3. The volume is 5E11m^3, thus mass is 1.5E12 tons. So your mass estimation is off by 6 orders of magnitude. This makes the "clearing maneouver" take proportionally longer -- on the order of a hundred thousand years.
A successful API design takes a mixture of software design and pedagogy.
Solar sails are an example of a space craft using energy that does not need to be carried from earth but regrettably their power is very limited at the distance from the sun where you could possibly still nudge an asteroid.
"The likes of Facebook and WhatsApp are free to those whose privacy is of zero value."
Lets say you write a WEblog, on an article you saw on NASA's site. You want people to see it sure, you post it on /. Great, we all get to see some stuff about the Asteroid.
/.
/. ? If not just move on.
If you like it you should be thanking coondoggie
for posting his WEblog. He posted the NASA link
in the first few lines of the article. SO we get both A link on /. and a link to the NASA source.
/. in the first point.
/.
I send the /. link. I do not by pass it.
One of my friends replys to all, "Oh, I get it
here is the link" and he sends the by pass link.
Do you see?
NASA seems to not be all into the promotion thing. So its not going out of its way to post this on
So I ask you, Did you liked seeing the info about the asteroid on
So you see CmdrTaco also the right thing! If he bypassed coondoggie then there would be no reason for coondoggie to post to
When I e-mail friends about stuff I see on
PS. I have mod points, I did not use'em. I wanted to tell you about your error. So I saved your karma. Did I do the right thing?
Actually, I was calculating momentum - not energy ratio - if you check the result of calculations I had mentioned (100 M to 10 M kms distance). But, I agree that my post was misleading since I mentioned energy ratio and not momentum specifically.
Also, for dino-killer I dont think any impact option is feasible at all - other than the hovering spacecraft idea. But the probability of dino killer is pretty low, compared to the 100m asteroid. So, I was considering for moderate asteroid impacts (torino scale - 8/9).
I was just wondering whether it is possible for such impacts?
rajmohan_h@yahoo.com
Here is a low bandwidth and pixel-efficient version: .
2019 is going to be the year of Linux on the desktop.
Need not be. Check out gravity assists.
How are they supposed to protect it from mynocks chewing on the power couplings?
I swear to God...I swear to God! That is NOT how you treat your human!
Nothing comes for free, even in a gravity assist. Every Newton Second of momentum gained by the craft is a Newton Second lost by the planet or moon giving the gravity assist. Nothing comes for free. The real question is who pays.
When our name is on the back of your car, we're behind you all the way!
I hope the satellite doesn't get Marooned Off Vesta.
Well lets take a closer look at this submission.
1.) The first sentence "NASA today said that its Dawn spacecraft snapped the first image of the giant asteroid Vesta it hopes to rendezvous with in July.", with an embedded hyperlink, seems to indicate that what I click on should bring me to a NASA web page. It doesn't. The link goes to a blog.
2.) The official NASA news release could have been easily embedded into the summary. It wasn't and that wasn't an accident. It is to force a click thru and generate the submitter revenue.
3.) The submitter is the writer of the blog, self pimpage if you will. This site used to be a community that posted links to interesting articles they have come across in their web surfing. This isn't a reader submitting an article, this is a blog writer trying to drive traffic to his site.
That's awesome. You should be writing documentaries like this one: http://www.imdb.com/title/tt0120591/
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
I guess at that distance, you can't yet see the little French prince standing on it.
Isaac Asimov's first sale was Marooned Off Vesta.
I, for one, would welcome having the mission commemorate him somehow.
Isaac Asimov wrote a short story called Marooned off Vesta
You're making a (common) incorrect assumption: that the change in velocity you impart maps linearly to a change in distance in the future.
When trying to avoid an impact, the best approach is to shift the phase (the location within the largely fixed orbital path) so that the intersection with the orbit of the Earth occurs either a little before we get there, or a little after. Thus most of the time you're either pushing or pulling in the velocity direction (changing the period ever so slightly).
The thing about the orbit phase, though, is that its incredibly sensitive to anything you might to do the orbit, particularly when you start talking about multiple revolutions. Slight period shifts compound and build up, and a small change leads to a much larger changes later (much larger than distance = velocity*time would suggest). As you might imagine, this can prove to be a huge advantage for any mitigation plan that has a good lead time (10-20 years). Thus while the 70 days estimate is probably decent, most serious mitigation plans focus on early detection so that we can take advantage of gravity to help us out.
Ummm... orbital velocity is inversely proportional to its altitude above the earth. For LEO stuff, it's about 17,000 MPH (sorry about the units). If you want a faster velocity, you have to orbit lower, and then atmospheric drag would take it out within a few orbits. The moon's tangential velocity, relative to the earth, is only about 2700 km/h (or 1700 MPH).
Less is more.
Didn't we learn our lesson the first time we tried to colonize Vesta and Telus?
It does seem unnatural to have a giant 8bit blob flying our way.. or any where in space. It's like that game asteroids.
Very informative. I'll run some numbers to see whether phase shifting would work in a short-term scenario (6 months advance warning).
A successful API design takes a mixture of software design and pedagogy.
NASA seems to not be all into the promotion thing. So its not going out of its way to post this on /.
Bullshit. NASA has a huge website and sends out press releases to the media.
So I ask you, Did you liked seeing the info about the asteroid on /. ? If not just move on. If you like it you should be thanking coondoggie for posting his WEblog. He posted the NASA link in the first few lines of the article. SO we get both A link on /. and a link to the NASA source.
Coodoggie is a parasitic plaigiarist. He's using NASA's content and adding his own ads, then whoring for hits here. His submission had no links to the NASA story, only his own blog. And he DID NOT provide a link to NASA in his submission. In his blog he steals not only NASA's story, but hotlinks their images.
So you see CmdrTaco also the right thing!
He did, finally, after seeing the comments here. If you look now, besides correcting the typo in the headline "NASAsatellite" (from Coodoggie's submission) NASA's page is now linked directly.
When I e-mail friends about stuff I see on /. I send the /. link. I do not by pass it.
If I was your friend (not likely, I guess) I'd sigh at you sending me to a page which had a link to a blog which had a copy of a story from a real site. After a while I'd just ignore your posts. You don't need to credit every asshole who mentions an article. Just go to the source.