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NASA Set To Launch Probe To Mercury
antispam_ben writes "CNN is reporting the upcoming Messenger mission to Mercury is set to launch August 2. The spacecraft uses a combination of technologies (insulation, Peltier devices, careful design and orbit, always keeping the shield side toward the Sun) to keep its electronics at room temperature."
I'd rather have them probe Mercury than Uranus.
...well, compared to the melting point of Tin anyway...
'Don't worry' said the trees when they saw the axe coming, 'The handle is one of us.'
I would hope they would make it come down to that temperature, I don't know of any kind of insulation that would actually do that.
Better hope Microsoft isn't watching, they may sue for copyright violation.
Nasa: But it isn't MS Messenger!!
Gates: I don't care, gimme mo' money beeyatch!@#
Der Tod ist der einzige Weg hier raus!
Nasa's Messenger? I wonder if Trillian will cover it...
There are two kinds of people in the world: Those with good memory.
Is room temperature an actual degree? I always thought it was just the temp of the envirnment that the time. If that's the case, room temp for the spacecraft is pretty hot no?
Since aerogels have much higher thermal insulation values than practically any other medium except hard vacuum they are especially excellent insulation candidates in poor to moderate vacuum ranges.
And it rendered on, until the end of its days.
as long as its room temperature in there, why not toss a few people/monkeys/whatever in with it?
Whoa, Peltzer devices? Awesome. I'm not sure how it's going to help us in space, but who am I to say that putting a smokeless ashtray, a juicer and a weird swiss army thing with a toothbrush that shoots out toothpaste onto a space probe is wrong?
http://www.babysmasher.com
http://www.openingbands.com
Does "always keeping the shield side toward the Sun" count as technology?
Sorry if I'm skeptical about this stuff... not in the moon hoax sense, but in the building a base on the moon and sending people to Mars sense.
Is this a novelty or something? Why does it even need to be mentioned?
...developed by nVidia for the NV30 launch, but scaled back because they only need to protect Messenger from a class G star as opposed to a modern graphics card.
While most other planets have been well studied, Mercury has not even had half its surface mapped! Messenger has non-visual light detectors including a laser altimiter which will let it map the whole planet, counteracting its slow rate of rotation. I hope the launch goes well and look forward to the data return. Kudos to NASA for doing some good science on what is considered a less sexy target than some others which seem to hog all the research money.
$#!^ happens, but why does it always have to happen to me???
...to keep its electronics at room temperature.
But what about the other side? Lets ask Roosevelt E Roosevelt:
Well, thank you, Roosevelt. What's the weather like out there?
"It's hot. Damn hot! Real hot! Hottest things is my shorts. I could cook things in it. A little crotch pot cooking."
Well, can you tell me what it feels like?
"Fool, it's hot! I told you again! Were you born on the sun? It's damn hot! I saw... It's so damn hot, I saw little guys, their orange robes burst into flames. It's that hot! Do you know what I'm talking about?"
What do you think it's going to be like tonight?
"It's gonna be hot and wet! That's nice if you're with a lady, but it ain't no good if you're in the jungle."
Ahh, what a great movie.
Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
For more information, see ESA BepiColombo page.
Auferre trucidare rapere falsis nominibus imperium, atque ubi solitudinem faciunt, pacem appellant.
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M'Ger: It's getting hot in here, so take off all your clothes.
P.S. Please send more info on carbon-based units infesting Earth.
"...the spacecraft must swing once past Earth, twice past Venus and thrice past Mercury before slowing down enough to slip into orbit around Mercury"
Her>That's the 2nd time I've seen Mercury! Stop and ask!
Him>I will not ask for directions! I know where we are now
Her>I have to pee! And you promised we'd get some Venutian shopping done!
*NOTE* - It is rather interesting that the craft must maneuver like this to get a stable orbit and not get crushed.
I know thermal issues have always been central to spacecraft design, but this sounds like a nicely engineered approach to temperature control.
I'm reminded of the faulty heater on one of the Mars Rovers. Could such problems be avoided or at least mitigated by use of more passive thermal management (insulation, heat pipes, heat sinking/sourcing)?
I'm also reminded of the Russian probes to Venus which had uderstandably short lives due to both heat and pressure (possibly corrosive gases as well).
I'm firmly in the camp that promotes more unmanned probes, maximizing the power of money spent on advancing spacecraft technology and knowledge from expanded exploration rather than blowing it all on the dubious value of letting a person stand on Mars.
"but can't we have one spot in the solar system without our flag on it"
What, other than Russia, China, Africa, and the other 90% of the planet that isn't on the North American sub-continent...?
'Don't worry' said the trees when they saw the axe coming, 'The handle is one of us.'
Can someone please tell me where I can buy this special insulation ... my damn electric bill is high as shit!
My Web Site - www.ocean-liners.com
Even though Mercury is 50 million miles from Earth at closest approach, Messenger will travel 5 billion miles to get there. It's technologically infeasible to fly straight to Mercury, a trip of a few months, and so the spacecraft must swing once past Earth, twice past Venus and thrice past Mercury before slowing down enough to slip into orbit around Mercury.
Can someone explain why such a convoluted and time consuming route is required?
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
Entec case fans, Swiftech water cooling with dual radiators, Thermaltake fanless PSU, PC Power bay coolers, the works! Lian-Li designed the case to the BTX standard, and the radiation-hardened 486 is overclocked to 100MHz! All they need now is the NASA case badge...
My Other Computer Is A Data General Nova III.
No.
The funny thing is that they are going to 'plant' the flag by crashing messenger into Mercury. And here I was thinking that flag-burning was a criminal offence in the USA.
No.
It's just a marker that we went there, not that we own it. Sheesh, settle down.
Hokey statistics and ancient misconceptions are no match for a good thought in your head, kid!
[SNIP] Bachtell used X-Acto blades to cut the 3M Nextel fabric and then used an industrial sewing machine to stitch the off-white pieces together into an 8-by-9-foot quilt, using Teflon-coated fiberglass thread. It was a nasty job; the itchy, ceramic-fiber cloth sheds and is bad to inhale.
You see all these people working on these satellites wearing protective clothing, not to protect the people but to protect the equipment. If we have learned anything thing, it's to protect your lungs and eyes. Imagine breathing that fiberglass and some form of ceramic fibers. I guess it's not popular to wear a $30 respirator when dealing with these exotic substances. For you though; if you feel like wearing one then do it - your not a bigger man breathing fiberglass than not.
There will always be homeless and by and large we take of most of our mentally ill. I'd rather spend it on space exploration than pumping some pork into politician's buddies pockets...but then again, we'll have that for awhile too. We all benefit from space exploration. New technologies are discovered, invented, born, what have you.
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you'd think that it would be easier for him to come to us. Nevertheless, it's nice to see that we are taking the first step in establishing contact.
"Look Lois, the two symbols of the Republican Party: an elephant, and a fat white guy who is threatened by change."
Comment 2: Actually, you can colonize Mercury. It wouldn't be easy... but it is conceivable (in a twisted sort of way) to put a colony on the dark side. Oh, btw, the colony would have to move opposite the planets rotation to stay there or else risk extreme sunburn...
we better thank our lucky star that the Sun is not about to be overclocked...
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As with any planetary probe, they are using the scientific standard of the metric system. Of course, as Mercury is smaller than Earth the meter also is smaller. As usual, Earth meters are used until Earth escape velocity is reached. Solar meters are used until the craft decelerates at Mercury. The Mercury meters will then be used for the remainder of the mission.
Well as long as they don't use feet and inches they should be safe
All that technology - what a waste. The cost too!
If they had sent it at night...
For problems, seek only the simplest solution, complexity brings with it more problems.
Sustainability and energy independence essay
False dichotomy. One could opt not to put any flag there.
Isn't pride one of the seven deadly sins?
I like their cooling solution much better; high temperature superconductors and peltiers to move the heat to a central location, where the kinetic energy is used to power a communications laser.
Too bad our current superconducting technology is scaling more slowly the higher temperature it gets. What we're currently calling "high temperature" means room temp. We'll make it there eventually. But without a whole new technology (nanotech anyone?) we'll never make superconductors that remain super conducting at temperatures much higher than that.
But what about a laser powered by heat? Can it happen without having to reach the ionization temperature of the lasing medium? Anyone have any insight?
I am disrespectful to dirt! Can you see that I am serious?!
And here I was thinking that flag-burning was a criminal offence in the USA. It definitely is, if you consider laws to be stricken as unconstitutional to be valid.
If you don't know where you are going, you will wind up somewhere else.
I'd say they are assuming a bit too much. First of all, they are assuming that someday, someone will drop by and find that flag. Secondly, i personally wouldn't be so optimistic as to think that America and its star spangled banner will everywhere and always be remembered. Supposing that a future mission would actually find that flag on Mercury, the odds are that it would only serve to show that someone has already been there.
Man is a slave because freedom is difficult, whereas slavery is easy.
We're already on the only planet which he has put his flag on. You going to stay here and hope nothing bad happens?
I've read analyses which say that the poles of Mercury have permanently shadowed areas which are close to sunlit zones (for power) and just might contain water ice. So yes, it may be possible for people to live there. (Getting on and off would be difficult due to the density; the kinetic energy energy of orbit is proportional to the density, so you couldn't use a LEM-equivalent lander despite the rough equivalence of the size.)
Sustainability and energy independence essay
Correct. According to article II of the Outer Space treaty (signed by the USA): "Outer space, including the Moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means."
For those that care, here's the link for the NASA site on Messenger. http://www.nasa.gov/mission_pages/messenger/main/i ndex.html
I know the future of exploration is in the private sector, but must NASA pander so obviously to its industrial sponsors? At least the craft's design is pretty cool... http://new-cars.com/concept/2003/mercury-messenger -concept-photos.html
Ceci n'est pas un post.
False dichotomy. One could opt not to put any flag there.
:)
I'm hopeful that (more) future spacecraft will have bold company logos on them instead of national flags. THAT would get rid of this silly flag debate.
Isn't pride one of the seven deadly sins?
Yes, but not everyone has Christian beliefs or has a negative view of pride in one's accomplishments.
Tag lost or not installed.
...isn't the 5 gigamile trip. It's the launch window. They have a 12 second launch window to either launch it or wait for the next 12 second window-- the next day, at the earliest. Because of the multiple fly-bys, the math gets a little complicated, and error tends to cascade towards failure.
;-)
Talk about performance anxiety!
Wife: OK Honey, I'm ready. You've got 12 seconds.
Enough for a high school boy, I imagine, but not us mighty slash dotters, right?
A month later the rescue ship arrives at the crash site and sees footprints heading off into the night. And coming over the horizon 180 degrees away from there is a very dusty and extremely tired astronaut :-)
Real Daleks don't climb stairs - they level the building.
It definitely is, if you consider laws to be stricken as unconstitutional to be valid. How long was the discussion here on the Pledge of Allegiance? A lot of people seem to consider laws valid, constitutional or no, where flags and things are concerned.
Real Daleks don't climb stairs - they level the building.
The planet does indeed spin - Mercury rotates on its axis 1.5 times per solar orbit (see http://www.solarviews.com/eng/mercury.htm). Because of this 3:2 resonance, a Mercury solar day (sunrise to sunrise) is equivalent to 176 Earth days.
e sign.html.
So what this means is that for every Earth year Messenger is orbit, 4 Mercury Years will pass, which consists of 2 Mercury Solar Days (see http://messenger.jhuapl.edu/the_mission/mission_d
This gives the spacecraft many passes over the light and dark side of the planet, so much that they can spend one (Mercury) day doing global mapping and the second (Mercury) day doing targeted science investigations.
In terms of heat - the highly elliptical, near polar orbit is designed so that the heat shield always faces the sun, giving the instruments a nice room temperature setting on the other side of the shield. There is the possibility of heat from the surface, but the instruments are designed to take that into account.
Gilthalas
Software Engineer, Space Dept, JHU/APL
Support Space Science!
Ahhh. One of those "never take pride in your work" folk. Sorry chum, not everyone thinks non-excessive pride is bad. In fact, some even think that excessive humility is bad. And, probably fake, thereby making it excessive self-pride.
So, let's hope he doesn't screw this one up! Don't press the red button....whatever it does, don't press it!
- launch_0715.html
Here's an article with a bit more info than the quoted CNN story:
http://planetary.org/news/2004/messenger_ready-to
Oh, I'm sure it'll happen.
See? Proof by Bartlett's. :-)
True. I was hedging my bets, though. American jingoists, in my personal (and thus necessarily limited) experience, tend to be the same sort who assert that America is a Christian nation.
Karma: pi (Mostly due to circular reasoning in posts).
...so this mission doesn't have to worry about providing power like the missions to the outer planets. There should be more solar power than they could possibly want. That's probably why the solar panels are 1/3 solar cells and 2/3 mirrors.
Of course, they have other problems that don't occur on outer planet missions like making sure your space craft doesn't melt.
That would be The Johns Hopkins University Applied Physics Laboratory, where I used to work. NEAR was the Near Earth Asteroid Rendezvous, the spacecraft that landed on an asteroid (a year or two ago?). I know a number of the people from APL involved in the project. There's a pretty detailed article in our local paper (local to JHU/APL) that describes more of the background. And of course their Messenger website is informative too.
I mod down all the "free iPod"-sig losers.
A factor that I can't judge is that many aerogels are made of silica, which has a much lower melting point than ceramics like alumina; it may be that the available aerogels were not sufficiently heat-resistant to do the job.
Sustainability and energy independence essay
The Venera landers were able to make it down to the surface, and IIRC one or two of them actually sent back pictures for a while. Their lifespans were very strictly limited by their insulation; as heat soaked in there was no way to pump it out again, and it did not take long before the electronics were too hot to function.
Sustainability and energy independence essay
False dichotomy. One could opt not to put any flag there.
We *could*, but why should we? You don't like our flag there? Go take it down and put yours up. Or a UN flag if you're so 'community aware'...
Isn't pride one of the seven deadly sins?
Is it? Okay. Um. So what was the point again?
We have pride in our accomplishments. I'm sorry if you're jealous of our feats, but too bad.
"Ignorance more frequently begets confidence than does knowledge"
- Charles Darwin
I'll bet that Newtonian physics was good enough, and GR corrections would have been down by the 5th decimal place or lower. It is barely possible to measure GR effects in the precession of the perihelion of Mercury, let alone in the delta-V from leaving your burned fuel lower in a gravity well.
Sustainability and energy independence essay
Okay, first of all, I don't remember reading anything in the article about Atzanteol's contribution to the Messenger program, so calling it one of "our" feats is stretching it a bit.
Second, I'm from Ohio. Insofar as anyone not connected to NASA can take credit for this, I can, too. I just don't see any reason to scatter litter all over the cosmos. "Give a hoot; don't pollute." Remember that one?
I'd prefer NASA's shrinking budget get spent on things like... oh, let's say... science.
And neither do I.
Historically speaking, the seven deadly sins weren't supposed to be things you should never do. They were actually considered positive things. What made them deadly is that it seems to be human nature to over-indulge in them, and that can lead to serious problems. The deadly sins were acts that (initially) monks needed to be mindful of within themselves. "All things in moderation," as it were.
The point, which you seem to have missed, is that I consider this excessive. Now, reasonable men may differ on this, and if you disagree, fine. But don't assume that just because I'm less of a braggart than most, that I take no pride in what I do. Announcing that someone less prideful than you must have no pride at all is yet another false dichotomy.
I saw a very nicea idea for a Mercury colony in a story once. What you do is to lay a railroad track around the equator. On the track is, well, a city. The city is pushed around the track by thermal expansion of the rails, so it doesn't even need power.
I choose to remain celibate, like my father and his father before him.
I don't know if the ellipticity of Mercury's orbit is such that the apparent motion of the Sun can reverse, and I'm not about to go digging for all the numbers when I have paying work to do. Maybe you can either document it or refute it.
Sustainability and energy independence essay
naeem
from Red/Green/Blue Mars. Not sure if it was described in Green Mars or Blue Mars... Power and light came from solar collectors in orbit , overhead. Read them too.
then why a flag? Why not a plaque that shows where the craft came from? That would probably last longer, and be relevant farther into the future.
I'm in the hole of the broadband donut.
Because the flag is *not* actually meant so much for future generations (from other planets?) to see, but for people living on this planet right now. The message is: "America was here." "America is a great country" -- for not any old country can build and launch a probe to Mercury.
Man is a slave because freedom is difficult, whereas slavery is easy.
For example, if Mercury's axis were exactly perpendicular, and you wanted to keep stay at least one mile below the horizon, and you round Mercury's radius to 1500 miles, then your track would only have to be about 55 miles away from a pole for a total length of about 345 miles. That's substantially shorter than the 9500 mile equatorial track you'd otherwise have to build, and since the angle of incidence would be much shallower your track wouldn't get nearly as hot during the day.
Also, since Mercury's day is about 59 Earth days long, a base on a near-polar track would only have to travel about .25 miles per hour. Contrast that with the more spritely 6.7 miles per hour of equatorial speed you'd need to maintain. If the base-moving motor were to break down, a near-polar astronaut could easily manage that pace on foot during an emergency evacuation.
Dewey, what part of this looks like authorities should be involved?
to keep its electronics at room temperature."
rtta
-x
We paid for the thing, we can take pride in it. I don't play for the Red Sox, but I can take pride in the 'home team' winning. Sorry that you feel no connection to our country. You should try, it's really quite nice here.
And I doubt a flag really cost that much, nor is it that much 'litter' on an entire *planet*.
"Ignorance more frequently begets confidence than does knowledge"
- Charles Darwin
If I had the points today. Interesting idea about the polar route.
Yow! I'm supposed to have a plan?
The hard part of the problem you were given was the continous burn since that makes a simple problem that can be solved explicitely into a numerical-methods problem that is pretty involved if you don't have a programmable calculator. I don't recall ever being given that question (it's pretty unrealistic too since, to date, there has only been one spacecraft that has used a continous-burn engine). Unless this was a take-home test (in which event kudos to you for solving such a difficult problem which a general Physics course usually wouldn't go that in depth) or your memory is a bit foggy--or you wasted your effort on such a trivial peturbance of its orbit.
So who else is missing the big picture? I mean, if we can insulate an alloy against temperatures that extreme, why isn't my RAM running at 4ghz? huh?
For those lacking taste, the reference is to Good Morning, Vietnam
InfoSec that matters, when it counts.
contrary to american belief, the USA doesn't extend to Mercury (or even to most of Earth)
Don't forget Monster Garage, Monster House, Monster Car, Monster Bike, uh ... etc. This infotainment is all about entertaining the plebians, while pretending to inform every once in a while.
I also lement the direction the Discovery Channel, TLC, etc, have gone.
Global warming is neither science, nor politics. It is a religion.
This guy spent a lot of time optimizing these imgages, and offers a very cool site about the Soviet Venera program in general. Very cool stuff.
Aerobraking was used by Mars Global Surveyor (still in orbit but only needed aerobraking initially) but no other spacecraft has used it since. I assume their analysis of the technique has lead them back to using reentry rockets instead. I'm not saying they won't work but if they'd been the cat's meow on MGS then they'd have used them everywhere, like they've now gone with airbags on the Twin Rovers.
$#!^ happens, but why does it always have to happen to me???