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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."
...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.'
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.
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?
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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.
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.
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.
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!
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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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
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?!
It shouldn't be all that hard since in space thermal control based almost solely on radiant energy. Even though the side facing the sun will get very hot, the side facing away from the sun is exposed to empty space with a temperature near absolute zero. If you simply reflect most of the sunlight away on the hot side, slow down what gets absorbed with a little insulation, and arrange to radiate what does get through the insulation (along with any internally generated heat) on the cold side, you should be able to maintain a reasonable temperature.
From what I've read, one of the hardest parts about controlling temperature on this probe is to handle the times when it passes in front of Mercury. Then, the near-zero chill on the "cold" side is temporarily replaced with the radiant heat from the > 400 C surface of the planet. At these times the probe has to be closed up like an ice chest to maintain its internal temperature at reasonable levels until it gets away from the planet.
sure, and is the solar panels aren't generating quite enough power wire a flashlight to them as well and direct its beam back onto the panel!
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.
FRY: This is a great, as long as you don't make me smell Uranus. Heh heh.
LEELA: I don't get it.
PROFESSOR FARNSWORTH: I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all.
FRY: Oh. What's it called now?
PROFESSOR FARNSWORTH: Urectum.
...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?
Thank you for saving me the time. Some people just don't get that, on a spacecraft, you're dealing with a near closed system here apart from solar input. No matter how much insulation you have, if you're not A) reflecting the solar radiation away, or B) radiating the heat away from your craft, you're going to burn up.
Thinking that you can simply insulate a probe enough to handle solar radiation is like thinking that you could swim in a volcano for weeks if only you could find a good enough type of insulation. The insulation for the probe is to help reduce the effects of heating/cooling cycles, not to keep the probe's temperature down.
SILENCE BLATHERING TOADIES! We are your new masters.
You see all these people working on these satellites wearing protective clothing, not to protect the people but to protect the equipment.
Often it's to protect both the people and the equipment from each other. You may recall the "bad day" a year or rwo ago when a 200 million dollar sattelite under construction fell over (because someone took the platform mounting bolts to use in another project without documenting the removal, and later when they tilted the platform...). Some of the pictures I saw showed yellow tape around it to keep people out, as there was fear that some of the sealed gases would leak from damaged tanks.
Tag lost or not installed.
as long as its room temperature in there, why not toss a few people/monkeys/whatever in with it?
That would be because it's going to take several years to arrive.
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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
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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