1377297
story
hubie writes
"The NEAR spacecraft flew by the asteroid Eros at a closest approach of only 3 miles! Despite what the story says, that is much less than the altitude of a commuter aircraft. Stay tuned for some expected cool closeup shots."
Whoah... (Score:1)
Did anyone read about the Plutino rock they found between Neptune and Pluto? I love space.
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Pictures (Score:1)
It's got some pictures up from today.
Only three miles!?! (Score:3)
I propose a Congressional panel to carefully scrutinize NASA's policies in regards to alien surface-to-air defenses, and whether the NEAR probe and others (Cassini! The Saturnians are watching!) are unjust provocations to our extra-terrestrial brethren.
I, for one, would like to welcome our new overlords, and would like to remind them that as a loyal Slashdot reader, I can be instrumental in rounding up the open-source zealots to toil in their salt mines.
Eros? (Score:3)
Any ideas to what shape an asteroid named "Eros" would be?
Eros? (Score:1)
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Actually 3 miles is high for a commuter (Score:1)
NEAR got a little too near! (Score:1)
Eek. 3 miles is really close for a fly-by. I wonder how much gravity it felt from that.
Actually, the article is right on that nit... (Score:2)
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Pictures! (Score:2)
woohoo! (Score:1)
Hmm... looks like i forgot to put my soapbox tag in there....
Some Pictures (Score:4)
http://nssdc.gs fc. nasa.gov/planetary/mission/near/near_eros.html [nasa.gov]
Enjoy =)
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lemmie get a shot... (Score:1)
JDW
NEAR and first Mac in space (Score:1)
Well my entire thought was, that I remember reading that for part of the cheaper aspect on that mission for the main computer they used, an Apple PowerMac 9500/9600 or major parts from one.
This would totally go against that other story [slashdot.org] that talks about the first webserver and Macintosh computer in space.
Sorry I couldn't find the recent link
Commuter Aircraft (Score:1)
-- "On second thought, let's not go there. 'Tis a silly place."
Height and definitions... (Score:2)
3 miles high is... (Score:2)
This is awesome.... (Score:2)
"sex on tv is bad, you might fall off..."
Look on the bright side (Score:1)
We should've told NASA that 3 miles is too far. We should be able to see the whites of the Erosians' eyes, as well as their surprised expressions.
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Recent Link (Score:1)
Wasn't it on
High Value Mission (Score:3)
The NEAR spacecraft, and the information that it is gathering, are probably one of the most worthwhile missions that NASA has ever had. The detailed look at Eros that it is providing will fill in a lot of details about our scientific knowledge of asteroids.
You can expect to see similiar missions to asteroids in the coming years. SpaceDev [spacedev.com], a publicly owned company, is proposing NEAP [spacedev.com], the Near Earth Asteroid Prospector. This probe, tentatively scheduled to launch in 2003, was originaly planned to visit the Near Earth Asteroid (NEA) Nereus. Recent discovery of hundreds of previously unknown NEA's may cause SpaceDev to delay the mission, and redirect the probe to some better target asteroid.
Additional missions? None scheduled yet. But you can bet they'll happen. The accessable resources of the asteroids have an estimated dollar value of about $100 Billion per person currently living on Earth. Someday soon, someone is going to dig into that Bonanza.
Disappointing graphic in the article (Score:1)
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Eros Photographed, Buggers Discovered!!! (Score:5)
If you don't know what I'm talking about, read Ender's Game
pictures and project home page (Score:2)
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lukas
Satellite drunk drivers (Score:1)
Tech #1: Dude! Watch where you're going with that thing! You're gonna hit the big floating rock!
Tech #2: Nah. We'll miss it by a mile. Three at least. Quit back-terminal driving ya pansy.
...and it sounds pretty kinky... (Score:1)
Re:Eros? (Score:1)
Re:woohoo! (Score:1)
Not to be petty... (Score:1)
I think the author is confusing 'commuter aircraft' and 'passenger aircraft'. Passenger jets operate around 30 to 35,000 feet.
Just can't abide by misinformation. *grin*
-Greg
Re:Whoah... (Score:2)
False alarm. They found it was an escaped diamond from one of Liz Taylor's rings.
Near skirts?! Eros!? Closeup shots!?
And I thought
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Probe will come very close to Eros, then ... (Score:1)
your pain, i feel it. [ridiculopathy.com]
Downloaded the movie!!! (Score:2)
If that movie is to scale... That asteroid is pretty big.
I am thoroughly impressed and I like the NEAR team "spokes person" saying that the good news was they didn't hit it and there was no bad news. I think we are getting there. This is great. ;)
1996 launch date means probably 1993 technology. I can live with that. I know that 8051 is the processor they used for the Patriot missle and that did a good job of hitting skuds. Therefore even if they used a 68K or 386/486 hardened for space that would be great... That might explain why they were able to avoid getting to NEAR the asteroid. ;) It is probably something thing like 486 or 68K or ASIC which is good. This is only a guess considering the pentium was being hardened for space about 2.0 years ago.
I am excited, this is REALLY good news. ;)
Good WORK!!!
commuters (Score:1)
some more pictures (and a map of eros) (Score:1)
KABOOM! :o) (Score:1)
Wonder if they could also hit Eros
First techie:"hey, were we using miles or meters?"
Second techie:" Um, i think we switched to that metric syst.."
NASA is underfunded! (Score:2)
I probably shouldn't even respond to a post this ignorant, but I can't resist.
First off, the only probes that have been "crashed" into anything (with the exception of probes which are at the end of their useful life) have been called "landers". Any crashes have been purely unintentional! ;-)
Secondly, in those rare cases where a probe is sacrificed in a hostile environment (the upcoming drop of a Cassini module into Jupiter comes to mind), expending the probe is the only way to get any scientific data at all Believe me, the scientists involved would love to extend the useful lifetime of any probe if possible.
Regardless, it's hard to argue that NASA spends too much money - NASA's budget is tiny compared to what is spent on defense, for instance. The payoff from technologies and basic science sponsored by NASA is certainly far beyond anything we're likely to see from other government agencies. That said, I'd certainly like to see more private companies getting involved in space exploration.
Have a nice terrestrial rotation.
Re:Some Pictures (Score:1)
Holy cow! It's a rock! And it's in space! And it's got holes in it! And now we've got pictures!
And in a year, we're gonna smash our spacemobile into the rock! Yeah! Who's king of the world now, huh? King of the universe is more like it! Cha-cha-cha!
Ok, I'm done now.
for those not in the know... (Score:1)
You mean in orbit? (Score:1)
We interrupt your /. program... (Score:1)
After finding out that there are a race of insectoid beings living on Eros, the United States have immediately pumped billions of dollars into NASA for a quick mission. Initial reports are sketchy, but the President really liked the idea titled "Insects are for squashing". It utilizes our current technology of fly swatters and boots.
Re:Only three miles!?! (Score:1)
Put this in perspective. You're sitting out in your back yard, tossing back a Rolling Rock, when all of a sudden a grotesque looking alien object crashes into your pool. What would you think? How would you have any way of deciding whether the aliens were trying to destroy our civilization, or merely were sending out probes to investigate our odd little planet?
I wonder how much thought NASA actually has put into this sort of scenario. Do we need to take precautions to make sure that if, as unlikely as it may be, one of our spacecraft comes in contact with alien life, that it won't be interpreted as hostile or invasive? Hollywood has thrived on our fear of a hostile alien race invading Earth, while we at the same time run the (admittedly very, VERY small) of becoming the embodiment of an alien Hollywood staple.
My odd thought for the day.
Re:Pictures (Score:2)
Did anyone else laugh at the description of the "bird's eye view of the asteroid"? (South Saddle.) I had a fleeting image of some poor confused crow seeing this view as it flailed about with its useless wings and its last breath blew out into the vacuum.
Maybe I'm just too damn literal.
Good going Noam and the NEAR Team! (Score:1)
The NEAR team is racking up phenominal amounts of data about asteroids in general (and obviously this one in specific) that will undoubtedly take quite a while to analyze.
This project is one example of an effective, efficient, non-disasterous project that demonstrates that space can be done for cheap cost (relatively speaking) with the right management and mission concepts.
Now if only we can persuade NASA that the standard probe design (or even lander design) should not imitate the recreational lawn dart....
Actually, commuter aircraft do fly at 3mi (Score:1)
Re:Only three miles!?! (Score:2)
Re:woohoo! (Score:1)
Patriot success (Score:2)
Look here [fas.org] for the official story, or here [cdi.org] for another analysis.
But the really interesting report is the Postol/Lewis analysis, including detailed analysis of video evidence, is here [fas.org]
In the interests of balance, This [gbhap.com] is a response to it.
It's not a fly-by (Score:1)
Han Solo did better (Score:2)
Plus he was being chased by hostile foes through a dangerous asteroid field, and escaped from the giant worm which was living in the asteroid, which is why you won't see anyone making a movie about the NEAR spacecraft.
Re:High Value Mission (Score:2)
I agree! Now, why is it that the NASA homepage [nasa.gov] starts with links to speeches by NASA bureaucrats, and not to these amazing close-up photos of Eros? In fact, there are no links to NEAR anywhere on the homepage. In fact, there are no links to NEAR even on the "Hot Topics" [nasa.gov] page. Of course, you can still get directly to the bureaucrat speeches from there. Cause that's a pretty hot topic. Probably you'll all want to do that right away. Yeah. I'm thinkin' those speeches are gonna get purdy damn Slashdotted in jusasec here. Uh-huh.
Not a fly-by (Score:1)
NEAR has been in orbit around Eros for months. The orbit started at about 120Km out. They have gradually flown it closer and closer. The latest orbit is *very* close to the asteroid. Remember, this isn't a simple spherical object. The orbital dynamics are extremely complicated. Over the last few months, one thing they have been doing is building an accurate gravity map so that they can fly this close. I don't know how many "firsts" this mission has chalked up, but it's a lot.
Nice one NASA.
on-board processors (Score:1)
Well you couldn't be more wrong about what processors are in this sucker!
There's actually 7 on-board, 6 of them are Harris RTX2010's [intersil.com] (Harris is now Intersil). This processor can do 6 MIPS at 8MHz.. There is also one Honeywell 1750A [smad.com] that runs the flight program. (2.5 MIPS - The military hybrid of this chip also runs Linux [cleanscape.net] ; ;.)
I quote from the above
"All processors are Harris RTX2010's except the G&C subsystem Flight Computer which is a Honeywell 1750A." Nice little satellite for early 90's.
That's no MAC! (Score:1)
Well you couldn't be more wrong about what processors are in this sucker!
There's actually 7 on-board, 6 of them are Harris RTX2010's [intersil.com] (Harris is now Intersil). This processor can do 6 MIPS at 8MHz.. There is also one Honeywell 1750A [smad.com] that runs the flight program. (2.5 MIPS - The military hybrid of this chip also runs Linux [cleanscape.net] .)
I quote from the above
"All processors are Harris RTX2010's except the G&C subsystem Flight Computer which is a Honeywell 1750A."
Nice little satellite for early 90's.
GLOBE (Score:1)
What processors NEAR runs off of.. (Score:3)
Well you couldn't be more wrong about what processors are in this sucker!
There's actually 7 on-board, 6 of them are Harris RTX2010's [intersil.com] (Harris is now Intersil). This processor can do 6 MIPS at 8MHz.. There is also one Honeywell 1750A [smad.com] that runs the flight program. (2.5 MIPS - The military hybrid of this chip also runs Linux [cleanscape.net] ; .)
I quote from the above
"All processors are Harris RTX2010's except the G&C subsystem Flight Computer which is a Honeywell 1750A."
Nice little satellite for early 90's.
Commuter aircrafts (Score:2)
Re:Downloaded the movie!!! (Score:2)
Honeywell MIL-STD-1750A 9MHz
512K RAM
256K EEPROM
16K PROM
Attitude Computer... :-)
Harris RTX2010 6MHz
64K RAM
64K EEPROM
2K PROM
For those that care. The specs for these processors are impressive. ;)
Face on Eros (Score:3)
If you look at frames 43, 44 & 45 of this orbital animation of eros [nasa.gov] you can clearly see a huge boo-scary tortured-looking face on the surface! I know it's a meritless thing to point out and has no real scientific significance (like the infamous "face on Mars"), but considering that:
Re:on-board processors (Score:1)
Look at the specs on the memory they included in the satellite. I included it in my correction of myself.
Re:Can objects orbit at really low altitudes? cm? (Score:1)
Quick crash course in orbital flight:
Every second, Earth (and any other object, for that matter) pulls a smaller object tward it at a set ammount acceleration (on Earth, its 9.81 m/s/s). So, if you travel at 30,000 km/s (just the throw out a number) you will still fall twards the Earth at 9.81 m/s/s. However, since the Earth is round, you will go out 30,000 km every second, while falling 9.81 m. Repeat this over and over and you will form an orbit around the planet. Objects in orbit are quite literaly falling around the Earth.
If you want to go higher in orbit, you mearly go faster and you will automaticly be pushed there. To go lower, just go slower. This is why there is a set speed and height for objects in geosyncronis orbit (which is when you are hovering over a specific point on the planet's surface).
This shows that there is a practical limit to just how slow you can go around the Earth, or else gravity won't care how fast you're going, you're going to hit that mountian! :)
So, the answer is, yes, you could, if gravity were low enough and your craft manuverable enough.
I hope this was clear. It helps if you have a few diagrams to show, but I don't have the time to make a few and give you the links to them, sorry.
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Re:Can objects orbit at really low altitudes? cm? (Score:1)
You could actually launch a rock into orbit around Eros by throwing it. If it were spherical that would be kind of fun, pitch it, then watch it slowly come around the horizon from behind you.
Re:Only three miles!?! (Score:1)
Its funny, I read the law on the internet, and read about the team but now I don't have a clue as to where to start searching for it now. It was brought up in a Slashdot article many years ago, and with all the scrutiny Slashdot could muster at that time it actually turned out as legitimate.
Re:woohoo! (Score:2)
Re:Can objects orbit at really low altitudes? cm? (Score:1)
Go back to physics class or take some calculus and rethink your "go faster and you will automatically be pushed [farther out]" idea.
Color Pictures? (Score:1)
more pictures (Score:1)
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Re:Actually 3 miles is high for a commuter (Score:1)
Re:3 miles high is... (Score:1)
Entrance to alien Hall of Records found on Eros (Score:1)
Re:Eros? (Score:2)
Re:Entrance to alien Hall of Records found on Eros (Score:1)
Re:Some Pictures (Score:1)
In other words, the link works.
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Re:Some Pictures (Score:2)
Believe me, if Eros had holes in it, as opposed to craters, I'd be phoning my broker with SELL orders, and then practicing up on my Wing Commander and other 3D space-combat game skills.
Cripes, didn't anybody here read Ender's Game? The buggers are out there, I tell you! They're out there!
Re:Actually, the article is right on that nit... (Score:2)
Commuter aircraft these days are typically things like ATR-42s and bigger. Unless the trip is really short, they usually fly at FL180 (18,000 ft) and above. Turbines are just thermodynamically a lot more efficient higher up. Virtually all commuter airlines are running turboprops. True - Redwing Airlines in Missouri, whose fleet consists of a single piston powered Piper Seneca (unpressurized) aren't going to be flying that high, but the majority of commuter airliners will be up that high so that their turbine engines at least get good fuel economy. The commuter airlines that operate the new regional jets will be up at FL250 (25,000') and higher, rubbing shoulders with their major airline brethren.
Also, ATC is there to serve us, and not the other way around. If you ask, ATC will normally give, especially once you're out of the busy terminal area. ATC in the United States are very good at working with the pilots to get them what they need.
More near stuff (Score:2)
Re:Good going Noam and the NEAR Team! (Score:3)
Agreed. NEAR is an awesome bit of work. Though the mission came extremely close to disaster. The reason we're reading about this in 2000 is because they damn near lost the spacecraft on first approach, and executed a miraculous recovery. It delayed the mission a year (waiting for the next orbit), but it didn't cost us much in terms of scientific return at all.
It's also a great demonstration of the fact that if you're in orbit around something - thinking of NEAR, Eros, and the Sun - whether you throw an object "up" or "down" makes no difference, it'll intersect your position next orbit.
That is, if you want to go "up" or "down" and you're in orbit, you thrust "forward" or "back". The EROS recovery was basically "screw it, don't waste fuel chasing the rock this year, because if we just relax, Newton will put us back on target for another encounter next year")
Re:Not to be petty... (Score:1)
Many commuters fly at 18,000+ these days. They are pretty much all turbine powered, and turbines just operate more efficiently at higher altitude. Keeps them above all the VFR traffic too, and helps with weather avoidance.
Commuter airlines are now getting regional jets too, such as the Canadair regional jet and the Embraer offerings and the like. These cruise up with the big boys (FL250 and above), but they typically are doing the longer commuter airline routes.
Re:That's no MAC! (Score:1)
There are rad-hard versions of Power PC processors that could fly in space. However, these are emphatically not Macs. JPL flies and rad-hard RS6000, I believe, which has common lineage with the Power PC.
Any Color Photo ? (Score:1)
Do the NEAR spacecraft have a color camera ? I only find b/w photos of Eros.
How is it possible that in year 2000 it has no color camera !? The old 70's Viking Mars lander had one!
Re:Can objects orbit at really low altitudes? cm? (Score:2)
Both of your descriptions are accurate, it is just that you are describing different things. The parent post is talking about an object that is allready in a stable orbit. In that case if you increase the tangential component of your velocity you would move into a higher orbit. What you are describing is the tangential velocity required to maintain a stable orbit, which is also true.
Just because something doesn't make sense at first doesn't mean that it is wrong, maybe you just haven't wrapped your head around it properly.
Rocks (Score:1)
How did they come to be there given the level of Eros's gravity? If a meteor hit Eros, the debris from the impact would fly off far too fast to be recaptured by Eros, yet if the rocks aren't impact debris, where did they come from?
Re:Eros? (Score:1)
Re:Only three miles!?! (Score:1)
I'd be thinking "Hot damn! I bet I can get at least 10 grand for that on eBay!"
Quick! Call Ender! (Score:1)
Re:Actually, the article is right on that nit... (Score:1)
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But that can't be right... (Score:1)
Re:Some Pictures (Score:1)
Repealed in 1991 (Score:2)
Eros Photographs (Score:1)
"And here we see that, yes, surprisingly, this is just a big rock. Over here we have some holes, and here, just behind that small rock, is a big rock. And there's another rock. And another one. Lots of rocks people. Great stuff."
The only fool bigger than the person who knows it all, is the person who argues with him.
Eros Surface(s) near skirts (Score:1)
Test for censorware (Score:1)
I wonder if any censorware program will not block it.
Physics lesson #1 (Score:1)
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Re:woohoo! (Score:2)
Well, the last intentional crash of a probe was the Lunar Prospector [go.com], which was a wildly successful mission. NASA achieved all their goals including more accurate mapping of the moon than ever before, and once the mission was over the Prospector would have become so much space junk.
Except there's been a speculation about the moon that's lasted since we first began studying it in earnest. Does the moon have any water, even in crystaline form? They decided to sacrifice a sentimental piece of space junk to observe the impact and do a spectral analysis of the resulting shower of debris. Unfortunately, the results were negative. No water on the moon, at least in the region they hit.
What if they had? Well, water is a fundamental requirement for life, as well as one of the ingredients they use for propellant in outer space. So if they'd found ice on the moon it would have increased the chances of a lunar base by a large percentage, meaning we'd have a relatively convenient launching base for the exploration of the rest of the solar system. So don't knock it: there was a point to it.
As for the unintentional crashes, all I can say is that when you mix up your math you get all sorts of problems. NASA got too cocky and skimped on their error-checking in their haste to get projects out the door. They're paying for that, but I still support them. In times of peace, the kind of technological breakthroughs we've experience can at least in part be due to the push for space exploration. That air conditioning unit you can't live without? Space exploration. Minaturization of technology? Space exploration. Don't think that just because we're putting money into a project that doesn't provide immediate gratification (except for those astronomy buffs among us), we're not also researching a better way of life for everyone. If they figure out efficient waste recycling, [go.com] it'll have benefits for the entire world.
Re:Physics lesson #1 (Score:1)
300 000km/s. Nevertheless, everything else you are saying is probably true.
Physics lesson #2 (Score:2)
If you want to try working out the orbital speeds yourself, you'll need the gravitational constant G (6.67 * 10^-11 N m^2/kg^2) plus the mass and dimensional data on the NASA page linked above.
I find it interesting that you could land on Eros with the equivalent of a big pogo stick, and launch yourself to escape velocity the same way.
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Re:Physics lesson #1 (Score:1)
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Physics lesson #3 (Score:1)
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Get your missions right! (Score:1)
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Would you settle for "close pass"? (Score:1)
This BBC article [bbc.co.uk] has the picture I was hoping for. Looks smoother than the Moon to me, lots of dust with a few rocks and no rims on the craters. It also contains this utterly hilarious typo:
I guess Eros is even more of a "near-earth asteroid" than anyone thought!--
Re:Only three miles!?! (Score:2)
How could any right-thinking red-blooded American like yourself just lie down and accept the threat from these alien sons of bitches? Surely you're not going to let this threaten democracy and our way of life? Show some true Yankee grit and tell NASA and the Air Force to put a nuke right up their ugly green ass :)
Fun with physics! (Score:4)
You are right about being able to orbit at any altitude, of course, friction of the atmosphere would become significant at lower altitudes.
You were only partially right when you said that the earth's gravity pulls at 9.8 m/(s^2), actually, according to Universal Gravity, two bodies will attract eachother with a force governed by the following equation:
F=(G M m)/(r^2)
Where F is the force of attraction, G is the gravitational constant (about 6.67*10^-11 m^3/(kg/s^2)), M and m are the masses, and r is the distance between the the two bodies' centers of gravity.
That is all well and good, but it dosen't tell us what the force of attraction for the earth is. To discover that, we have to use another equation, Newton's second law:
F= m a
Where F is force, m is mass, and a is (you gussed it) acceleration.
We can set F equal to F and yeald:
m a = (G M m) / r^2
We can cancel out the two small 'm's to get:
a = (G M) / r^2
We need a 'r' and a 'M', so I will now stipulate that the radius of the earth is about 6.38*10^6 m and that the mass of the earth is 5.98*10^24 kg. An abitious slashdoter could most likely find much more accurate figures, but these will fit our purposes. Consequently, we can find the acceleration due to gravity with:
a = (6.67*10^-11 * 5.98*10^24) / ((6.38*10^6)^2)
I hope you can see that 'a' would be significantly less were an object higher (say, 500km) from the surface of the earth, as 'r' would increase:
a = (6.67*10^-11 * 5.98*10^24) / ((6.38*10^6 + 500*1000)^2)
Back to the original question: How fast must an object to travel to orbit the earth at the surface? To answer that, we have to call apon yet another equation, that of centripical acceleration in circular motion:
a = (v^2) / r
We know that the centripical acceleration is the acceleration due to gravity, which we found to be 9.799 m/(s^2) at the surface of the earth, and we know 'r' to be the radius of the earth, so to find 'v' (velocity) we could have:
v = sqrt( a r )
As you can see, this is significantly less than your figure of 30,000 km/s!
(*) Us Americans, who's brains have been destroyed by the English System, would get more sense out of 17,687 mi/hr.