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Space

First Probe To Orbit Mercury May Help Us Learn How Planets Form 88

An anonymous reader writes "Next month, the first space probe in nearly 40 years will approach the planet Mercury, with an array of instruments that could help answer fundamental questions about how planets form. The mission is called MESSENGER, for Mercury Surface, Space ENvironment, GEochemistry and Ranging. On March 17 it will pull into orbit around mercury, after more than six years of maneuvering between the Earth, Venus and Mercury itself."
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First Probe To Orbit Mercury May Help Us Learn How Planets Form

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  • by Adambomb ( 118938 ) * on Tuesday March 01, 2011 @02:25AM (#35345346) Journal

    On the bright side the solar panels don't have to be very large," Blewett said.

    I see what you did there.

  • That article is far worse than your average /. post: it lacks cohesion, and sounds more like rambling than a serious piece of journalism. I would bet the author hasn't had it proof-read, probably not even by himself. There must be better articles around describing this event.
    • Agreed. "Because Mercury, unlike Earth, is not tilted relative to its orbital plane, there are areas near the poles where the sun would never come up over the horizon. Those areas are a lot colder than the rest of the planet. Most scientists think the mystery material is water. These regions were discovered when ground-based astronomers bounced radio waves off the planet." How is this 'mystery material' that the author is talking about relevant? We can infer, but for a topic that usually sends science repo
      • Oh yes that as well. And he's writing about "this mystery material" without having introduced it beforehand... what mystery material I'd say. Oh and considering the temperature there can be so many other ice-like substances, like methane or carbon dioxide. That there is water in space is no surprise - no water out there would be more of a surprise. I always hear talk about meteors being clumps of rock and ice.

        • by Anonymous Coward
          It wouldn't have been a mystery material if he'd introduced it, now, would it?
  • The mission is called MESSENGER, for MErcury Surface, Space ENvironment, GEochemistry and Ranging.

    They certainly did a lot of "ranging" coming up with that acronym.

    New game-show? "NASA would like to buy a vowel for....ten million dollars!" *clap* *clap*
       

    • by Tablizer ( 95088 )

      by the way, after budget cuts they shortened it to MESS

    • by mangu ( 126918 )

      The mission is called MESSENGER, for MErcury Surface, Space ENvironment, GEochemistry and Ranging.

      They certainly did a lot of "ranging" coming up with that acronym.

      Actually, ranging is an important part of any space mission. What they call "ranging" is measuring the distance from an earth station to the spacecraft and it's what allows then to calculate the orbit the spacecraft is following.

      Without accurate ranging the spacecraft would either get lost in space or crash on the planet. With accurate enough ranging one can even find out details about the planer's interior. Thanks to ranging, we know that Mars has a liquid core [sciencedaily.com].

      • by Tablizer ( 95088 )

        Yes, but don't almost all non-landing probes do that as part of their standard navigation? It's almost like calling a PC a "compu-fan" because it has a fan(s) inside.

    • Also, geochemistry? Shouldn't that be hermechemistry?

    • They certainly did a lot of "ranging" coming up with that acronym.

      One of the instruments on the probe is a laser altimeter, which is a kind of LIDAR (which stands for Light Detection and Ranging). So regardless of the stupidity of the overall name, the acronym letter actually fits.

      If I were in charge, though, I'd just call it "Messenger" without all-caps. The word itself is fine (and Mercury-related) without trying to cram it into a backronym.

    • NASA, if you want to call a probe "Messenger", just call it "Messenger" and explain to the members of the media who slept through middle school that you called it that because Mercury was the Roman messenger of the gods. You don't need to emulate the US Congress and try to justify the names you want to use with backronyms that violate several Geneva Convention prohibitions against torture (e.g. U.S.A. P.A.T.R.I.O.T. Act), and which even Stan Lee would be embarrassed by.
  • by Anonymous Coward

    how is plannet formed
    how solarsystem get pragnent

  • Video from MESSENGER (Score:4, Interesting)

    by SnoopJeDi ( 859765 ) <snoopjedi&gmail,com> on Tuesday March 01, 2011 @03:13AM (#35345492)
    OT, but one of my favorite spacecraft videos is the departure video [youtube.com] from MESSENGER.
  • This will let you see how things look from any spacecraft: http://space.jpl.nasa.gov/ [nasa.gov]

  • Thinking of Mercury also makes me think of the very good horror/sci-fi movie "Sunshine". (Partial SPOILER ALERT).

    I really liked it except the intensity of the Sun, even at those distances, was dialed up a bit too high. I mean, when the captain gets "blown" by the very brief exposure to the (dying) sun, it was a little too much considering he was in a very heavily heat shielded suit. And the ship wasn't even yet at Mercury's orbit! I guess just slowly being cooked to death was not dramatic enough for the

    • Oh, and to add to my nit-picking, when the thermally unshielded crew members are exposed to the vacuum of space (now in shadow) they shouldn't instantly freeze solid. They would, of course, eventually do so (if they were kept in shadow) but the thermal conductivity of a vacuum is so low it would take awhile (think Thermos bottles). And evaporative cooling wouldn't be that much faster (even Bedouins in the driest deserts don't get cold from sweating). Still the writer's needed a contrast between fire and

      • Re:Movie "Sunshine" (Score:5, Informative)

        by tragedy ( 27079 ) on Tuesday March 01, 2011 @04:49AM (#35345824)

        Just a note. Oxygen transport in your body isn't based on the oxygen being dissolved in your blood. It combines chemically with the hemoglobin. So, suddenly exposed to a vacuum, you still might have some gases come out of solution in your body, so maybe the bends, and your body would swell a bit quite possibly accompanied with some discomfort. I'm not sure what would happen with sinuses and eardrums and so forth. Also, if your lungs were full, you probably wouldn't be able to contain the pressure. I'm pretty sure it wouldn't be able to blow out your chest or anything, but there could be internal rupturing, or maybe the air would just force itself out of your mouth and nose. In any case, if you had enough oxygen in your blood to stay conscious for two minutes, then it looks like you'd stay conscious for two minutes regardless of the pressure (as long as you don't pass out from the pain of your ear drums bursting, etc.)

        Hmmm. Before posting, something just occurred to me about how good a pressure vessel your lungs might actually be. I looked up the PSI trumpet players manage, because I've heard about how professionals manage to rupture their lungs sometimes and end up with air directly entering their body cavities. I found this [abel.hive.no] which says that student trumpet players were able to manage 35-50 PSI and professionals between 75-95 PSI. The question there is how much of that pressure is actually found in the lungs and how much is produced by clever use of the lungs as a lower pressure air supply, producing the pressure mostly in the mouth and feeding it with careful work? I'm not sure, but it makes it seem that it's quite possible that a healthy adult may very well be able to hold air at around 14.5 PSI without even being forced to breath out. For that matter, if they're in space in the first place, they probably weren't even breathing air at 1 atmosphere to begin with. The US space program uses a mostly oxygen atmosphere at only about 5 PSI.

        So, it looks like you wouldn't want to just take a stroll out into the hard vacuum of space on a regular basis, but it looks like it's actually pretty survivable in most of our solar system.

        • Man.. you just grossed me out.. with science!
        • I think 15 seconds in vacuum is the limit. The lungs will empty immediately. Air is kept there by suction and you lose that in vacuum. Oxygen transport out of the blood and into vacuum means that the blood headed for the brain will have almost no oxygen so once that hits the brain you are gone. Having said that 15 seconds is enough to find the lever and close the door of the emergency airlock then pull the lever to blow the lock though I reckon the pulse of oxygen deprived blood would have knocked Bowman ou

          • by bytesex ( 112972 )

            You could still be saved by others though, after those fifteen seconds. In space, the question is for how long.

          • by tragedy ( 27079 )

            Little late to reply to this, but I'm going to anyway. From what I can find, it looks like you very well may be able to hold the oxygen in your lungs even in a vacuum. Air may be brought into your lungs by suction, which does rely on air pressure, but once it's in there, you hold it in with your trachea mouth, etc. It may or may not be the case that the lungs empty immediately, but what I can find suggests that you can probably manage to hold in the 5+ psi you're likely to have in your lungs. Also, even if

        • by Alioth ( 221270 )

          You won't stay conscious for more than a few seconds.

          The lungs are not a one-way system; effectively, if there is less oxygen in the lungs than there is in the blood, the lungs work in reverse and remove oxygen from the blood. At airline altitudes, the time of "useful consciousness" is something like 30 seconds. At 50,000 feet, time of useful consciousness is between 6 and 9 seconds because the lungs strip the oxygen out of the blood so efficiently. This is why if there is only one crew member in the flight

    • Unless the chromosphere of the sun is surrounding you pretty much any mirror will protect you from the sun. And the mirror doesn't have to be heavy. A thin sheet of polished metal will do fine. Good film though. Along with Moon its great to see indie SF films being made.

    • Here's hoping Messenger results aren't being displayed on live TV globally when suddenly the Messenger feeds wink out, and you hear a voice in the background sat "Oh, shit...did you see the size of that flare? I gotta get home to my family".
    • by hazem ( 472289 )

      It made me think of Asimov's short story, Runaround, featured in the I-Robot collection (among others, probably). http://en.wikipedia.org/wiki/Runaround [wikipedia.org]

      I'm particularly fond of the audiobook version read by Scott Brick.

      It features a funny robotics-expert duo, Donnovan and Powell, who are sent to Mercury after a failed mining mission some 20 years earlier. They have robots and plans to bring the station back on line, but of course, there's a problem... involving robots.

    • I was so pissed off when that movie turned into a damn slasher flick, they were doing everything right up until then.
    • And a believable scary "monster!"

      You mean the seemingly psychic space zombie? Sorry, how was that believable again? Or, for that matter, even necessary to the plot?

  • Messenger is a great name, perfectly respectable with a sort of a cute "ZOMG HI Mercury! LUV Earth!" edge to it.

    And then you just had to go and fucking ruin it with a horrendous backronym didn't you.

  • The article:

    Mercury also spins very slowly, and does so in such a way that a single day on Mercury lasts 176 days - two of the planet's years.

    Wikipedia:

    It completes three rotations about its axis for every two orbits.

    Which is correct?

    • http://www.nasa.gov/pdf/168019main_MESSENGER_71504_PressKit.pdf [nasa.gov] "page 6" (8/33)

      Rotates on its axis once every 59 Earth days, but because of its slow rotation and fast speed around the Sun, one solar day (from noon to noon at the same place) lasts 176 Earth days, or two Mercury years

      Although I'd say the article is clearer, both the article and Wikipedia are technically correct because Wikipedia talks about three rotations, not days. Calculating the length of a solar day on Mercury requires accounting for the orientation of a point on Mercury to the Sun; as Mercury rotates once, it also travels through 59/88 of an orbit, so one rotation != one solar day on Mercury and the article and Wikipedia are not in con

"What man has done, man can aspire to do." -- Jerry Pournelle, about space flight

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