Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
Space News

Messenger Flies by Mercury 170

Posted by ScuttleMonkey from the fun-in-the-sun dept.
Riding with Robots writes "Today, more than three decades after the last spacecraft visited Mercury, Messenger buzzed just 200 kilometers above the planet's surface. During the encounter, the robotic spacecraft conducted a range of scientific observations, including imaging swaths of Mercury's surface that have never been seen up close before. A few of the first pictures are now available, with many more to come in the next few days."
This discussion has been archived. No new comments can be posted.

Messenger Flies by Mercury More

Messenger Flies by Mercury

Comments Filter:
  • When will this ever end? :-)
    • Just cant wait to see the surface of Mercury ..
      Never know .. might be a nice Alien base on it's dark side :D

    • Re:Again? (Score:4, Insightful)

      by Amorymeltzer ( 1213818 ) on Monday January 14, 2008 @07:55PM (#22044304)
      Just as in Biology, a lot of what is observed in Astronomy is what's big, pretty, and easy. Venus and Mercury are two planets that are largely unappealing by normal standards - way too hot, completely dead and barren. It's always good to see good science being done for the sake of science, not public opinion. Cassini and the rovers were fantastic, but the less glamorous missions are just as important to our understanding.

      • Re:Again? (Score:5, Informative)

        by rk ( 6314 ) on Monday January 14, 2008 @09:45PM (#22045406) Journal

        Part of the problem, too, is that it's really tricky to get to Mercury due to the amount of delta-v you need to shed Earth orbit, plus unlike Mars, Mercury has a negligible atmosphere which makes aerobraking useless. That's why they did three slingshot maneuvers to get there. The navigation team at JPL has really outdone themselves with this flight, and are to be commended.

        It actually takes more delta-v to get to the sun than it takes to leave the solar system from here. This is why that whole "send dangerous waste to the sun" is a really bad idea. It takes a huge amount of fuel and if you miss, you've got a dangerous payload in a highly eccentric orbit that almost certainly crosses the Earth's. What could possibly go wrong? :-)

        And maybe it's because I'm a space nerd, but I think MESSENGER is glamorous as hell.

        • Re: (Score:3, Interesting)

          by MorpheousMarty ( 1094907 )
          Perhaps you could clarify something for me. After you break earth's orbit, why would it take any extra energy to get to the sun? (This is assuming of course that the garbage is pointed at the sun and timed so it wouldn't get close enough to Venus and Mercury to divert it's course. Why would getting away from the sun be easier than going towards it?

          And a solution to send garbage safely would be to aim it a bit high or low (perpendicular to orbit of Earth). The slingshot would almost never send it back towar

          • Re: (Score:3, Informative)

            by Tablizer ( 95088 )
            This is assuming of course that the garbage is pointed at the sun and timed so it wouldn't get close enough to Venus and Mercury to divert it's course. Why would getting away from the sun be easier than going towards it?

            If you point it right at the Sun from ground perspective, it will just come back to circle the Earth unless propelled really hard. One needs to find a way to bleed sun-orbiting speed off of it. There's no free lunch.
                     
            • You -could- bleed the speed, by say a solar wind sail paralell to the solar wind movement (this way the sail could be reusable, just reorient it to perpendicular and fly it back home on solar wind) - it would take a long time but we're not in a hurry with these.

          • Re:Again? (Score:5, Informative)

            by rpj1288 ( 698823 ) on Tuesday January 15, 2008 @04:24AM (#22047986)
            Actually, pointing something towards the sun wouldn't really send your payload into the sun unless you pushed really, really, really hard. To get something to approach the sun using chemical rockets, one must think about the concept of an orbit. An orbit is defined by the object's speed around its central body. Thus, in order to get closer to the sun, your payload would have to drop its orbital velocity to near enough to zero, if you want a fast collision. You would need to use energy to get to the limit of earth's gravitational influence, about 1,000,000km out. At this point, you would essentially moving with the same orbital velocity as the earth with respect to the sun. Escape velocity for Earth is about 11km/s. With respect to the Sun, the Earth has an orbital velocity of about 48km/s. This means that to get you probe to go on a straight line to the sun, you would need 59km/s of delta v, which is a hell of a lot, and delta v is (essentially) directly proportional to amount of fuel you must carry. Now, granted, you could take a more circuitous route to arrive at the sun, and use less delta v, but it would still be a significant fraction of the 59km/s.

            With regards to you second question, unless the highly inclined orbit was altered again at perigee and apogee with respect to the sun, your payload would return to the Earth's orbit.

            Note: I am not a rocket scientist, at least not for a while, but I have done a bit of interplanetary stuff like this. All the numbers come from google. And it is entirely possible I'm quite mistaken, but I hope this was a bit helpful.

          • Re: (Score:3, Interesting)

            by CheshireCatCO ( 185193 )
            The answer is easiest to see in terms of angular momentum. (Orbits are really all about angular momentum, more so than energy.) If you break free of Earth's immediate gravity, you're still in pretty much the same orbit as the Earth going around the Sun. You have to dump a lot of that angular momentum to reach Mercury or the Sun, and that takes quite a bit of work. Remember, escape speed from the Earth's surface is around 11 km/sec, but the Earth's orbital speed is around 30 km/sec. You have to dump abo
            • Thank you for your answer, unfortunately I still don't get why you couldn't pick an angle to escape the Earth that would get you to the Sun. I guess I just don't get orbits, but I will spend some time thinking about it. I don't see why you need to slow down to get close to the sun, I would want to hit it as fast as possible (I'm not a patient man). I do understand that if you leave the earth you're still moving like heck relative to the sun, I should probably meditate on that for a while. Thanks again.
              • Think of it like this:

                Escape speed from Earth is 11 km/sec and you end up barely moving relative to the Earth once you're reasonably far away (say past the Moon). So you share the 30 km/sec orbital speed with the Earth. That means that you're moving *sideways* to the direction of the Sun at that gawdawful speed. If you try to move toward the Sun, you'll still slip to the side and miss it. You've got to kill your sideways orbital speed first, and then you (automatically) drop down closer to the Sun. (Ir

          • Re: (Score:2)

            by Dieppe ( 668614 )
            Try this experiment. Go to a playground with a merry-go-round. You might have to go old school for that. Now stand on the edge and propel it, oh, clockwise. Get it going pretty fast. Now try to reach for the middle. Better yet, drop a coin like a probe from the planet earth. Where does it go? Toward the center?
          • The Earth is moving very quickly in its orbit.

            Imagine you are in an aircraft travelling over a target on the ground, and you have to drop some small projectile to hit that target just as you pass over it. If you just drop the projectile, the speed of the plane will cause the projectile to have a horizontal velocity equal to the speed of the aircraft, and you will miss your target by a wide margin. To make the projectile fall vertically, you have to throw it backwards from the aircraft with a backwards veloc

        • Re:Again? (Score:4, Interesting)

          by Tom Rothamel ( 16 ) on Tuesday January 15, 2008 @01:19AM (#22047108) Homepage

          That's why they did three slingshot maneuvers to get there. The navigation team at JPL has really outdone themselves with this flight, and are to be commended.


          Interestingly enough, the navigation of this flight was outsourced to Kintex [kinetx.com]. The mission itself is managed by APL... AFAIK, JPL wasn't particularly involved.

          • Re: (Score:2)

            by rk ( 6314 )
            Ah, quite right you are. Thanks for the correction. I've been out of the space game a couple years now, and remembering who's doing what (apart from the things I actually worked on... I was an MGS, Odyssey, & MER guy) isn't part of my daily routine anymore :-). So, yeah, the sentiment still stands, but for the KinetX and Johns Hopkins folks. That's some fancy flying!
  • Just looked at the photos and was hoping for something of higher resolution or of higher details. Is Messenger going to get any closer to the planet?

  • Three Cheers for NASA! (Score:5, Insightful)

    by spaceyhackerlady ( 462530 ) on Monday January 14, 2008 @06:26PM (#22043198)

    Hats off to the folks who put this together. I was in high school the last time we saw any closeup pictures of Mercury. Every time we send probes to other panets we find out really cool stuff. Messenger should be no exception.

    If we can't go there ourselves, we can send robots. Robots are cool. :-)

    ...laura

  • Correction (Score:3, Informative)

    by Kozar_The_Malignant ( 738483 ) on Monday January 14, 2008 @06:27PM (#22043216)

    >A few of the first pictures are now available, with many more to come in the next few days.

    Actually, only a few approach images are available. The first images from the close approach will not be available until 01/05/08 when Messenger has finished data collection and points its antenna towards Earth and begins to transmit data. Can't wait for images of a very harsh environment.

    • Oops... (Score:5, Informative)

      by Kozar_The_Malignant ( 738483 ) on Monday January 14, 2008 @06:30PM (#22043258)

      The first images from the close approach will not be available until 01/05/08

      That should be 01/15/08. After 15:00 EST.

    • Re:Correction (Score:5, Insightful)

      by the_other_chewey ( 1119125 ) on Monday January 14, 2008 @07:23PM (#22043950)
      The first images from the close approach will not be available until 01/05/08

      Could we please use unambiguous date formatting?
      Something like YYYY-MM-DD?
      I guess you actually meant 2008-01-15 with a typo.

      • Re:Correction (Score:5, Funny)

        by stefanlasiewski ( 63134 ) <slashdot AT stefanco DOT com> on Monday January 14, 2008 @08:10PM (#22044432) Homepage Journal
        *clearly* he meant 01/15/8000000000008 , which in in the Mecurian calendar means the first month, fifteenth day in the 8-Trillion-and-8th Mecurian solar rotation.

        Plus, the Mercury citizens have learned to simply abbreviate as '08' on their paper calendars-- if you write all the zeros, the paper calendars usually catch fire before you are done-- so it's important to write quickly!
      • How is 2008-01-05 unambiguous? Maybe something like 05-Jan-2008, where the month can't possibly be confused with day.

        • Re:Correction (Score:5, Insightful)

          by the_other_chewey ( 1119125 ) on Monday January 14, 2008 @09:16PM (#22045068)
          How is 2008-01-05 unambiguous?

          ISO 8601.
          Additionally, I'm completely unaware of anyone or anyplace using
          YYYY-DD-MM as a date format, and my googleing seems to confirm that.
          • I'm going to use that format from now on, and I'm going to call it the Reverse Polish Stardate.

          • Re: (Score:2, Insightful)

            by Mr. Slippery ( 47854 )

            ISO 8601.

            Standardization and unambiguity are different beasts.

          • Additionally, I'm completely unaware of anyone or anyplace using
            YYYY-DD-MM as a date format, and my googleing seems to confirm that.
            Yeah, but you are depending on your reader having that same knowledge? You can't expect everyone to know that factoid (you yourself had to check on google).

        • Re: (Score:3, Informative)

          by Detritus ( 11846 )
          Month names are not portable, they need to be localized. We have an ISO standard (YYYY-MM-DD) for dates, let's use it.

          • Re: (Score:2)

            by mattr ( 78516 )
            That's also the standard in Japan, but with periods: 2008.01.15
            which sanity is erased by common use of imperial reign (this is year Heisei 20).

            Matt

          • Re: (Score:2)

            by dargaud ( 518470 )

            We have an ISO standard (YYYY-MM-DD) for dates, let's use it
            Sure, as soon as the US finishes adopting the metric system... I say this in jest, but time/date is a lot harder to standardize than other measurement units and a lot of thought have poured into it. During the french revolution they tried to standardize all units, even time. They succeeded for all, except for time and and the US.

            • Re: (Score:3, Insightful)

              by MightyYar ( 622222 )
              I'll accept that the US is the last holdout of Imperial units when I can't walk into any pub in London and hear people ordering "pints".

              • Re: (Score:2)

                by dargaud ( 518470 )
                I think Nigeria is the only other holdout... As for the pint, it works fine and is unit-neutral if you just order a 'glass'... C;-)
          • You don't really need portability on an English-language web site, though.

            • Re: (Score:2)

              by Detritus ( 11846 )
              It can still be a problem for people whose primary language is not English.
              • This is an English-language site - and one which uses a relatively high level of vocabulary, at that. If they can get through all of the techno-babel and then get hung-up on the months of the year, I think they'll be able to deal :)
      • I prefer something like 14.JAN.08 myself...

        RS

        • Except it is the fifteenth. Or fifteen, I never know.

          And writing the month in letters is language-specific.

      • in before unix timestamp
      • How about we all just use day-of-year notation? 2008-015 (time unknown).

        Or, better suggestion, write the month's name: 15 Jan. 2008.

    • Re: (Score:2)

      by ashitaka ( 27544 )

      will not be available until 01/05/08
      Jan. 5th? May 1st?

      I know the following post was less vague as there aren't 15 months, but for clarity sake can we ask for ISO dates?

      2008-01-05: No mistakes.

  • great flyby animation (Score:5, Informative)

    by imipak ( 254310 ) on Monday January 14, 2008 @06:46PM (#22043492) Journal
    There's a really nice animation on the Flyby 1 page [jhuapl.edu]: 10Mb version [jhuapl.edu], 84Mb version [jhuapl.edu].

  • It's a FAKE! (Score:5, Funny)

    by Conspiracy_Of_Doves ( 236787 ) on Monday January 14, 2008 @06:58PM (#22043644)
    That can't be real! There aren't any stars [badastronomy.com] in the background!

    • Re: (Score:2, Funny)

      by Jefan ( 1096649 )
      And if you look closely in that first picture, you can see a Coke bottle in one of the craters in the lower left hand corner!

    • Re: (Score:2, Funny)

      by subnomine ( 849148 )
      So...like the 2008 Golden Globe awards?

    • Re: (Score:3, Funny)

      by Max Littlemore ( 1001285 )

      Not only that, but if you look closely enough, you can see it's just one of the faked moon photos upside down! Definitely a hoax!

  • A good quick read (Score:4, Informative)

    by coffee412 ( 787700 ) on Monday January 14, 2008 @07:22PM (#22043940)
    Section of Reworked Venera-13 Image http://www.mentallandscape.com/V_DigitalImages.htm [mentallandscape.com] Checkout the venus pics if you havent already from the link above. Mercury surface pics would be cool.
  • We all know about the Face on Mars, but I wonder if they will finally find the Butt on Mercury?
  • can we see the images in Google Mercury ?
    How about crater level imaging?

  • Global warming on Mercury (Score:5, Funny)

    by heroine ( 1220 ) on Monday January 14, 2008 @09:05PM (#22044946) Homepage
    There's a planet with a serious global warming problem.

    • Re: (Score:3, Funny)

      by TempeTerra ( 83076 )
      Nonsense. It's part of a perfectly natural cycle the planet goes through and if you stop driving your SUV you might even make the planet COLDER than it should be. There is no global warming problem ;)
    • [cue dorky serious response] Venus, despite being much farther from the Sun than Mercury, actually has higher surface temperatures. The reason is that its atmosphere is mostly CO2 and methane, which have created a very strong greenhouse effect.
  • ...that thought the headline referred to the Mercury Messenger program that is "compatible" with a certain large vendor's offering?
  • ... preferably the kind that has its SPF measured in "powers of ten".



    (Just kidding. I know the probe actually has a physical sunscreen that keeps it from being toasted).

  • Extremely Close (Score:4, Interesting)

    by PhotoGuy ( 189467 ) on Sunday January 20, 2008 @08:10PM (#22121732) Homepage
    200km! Wow, that's incredibly close to Mercury. For comparison's sake, geosynchronous orbit (where all our TV and most communication satellites live) are at 36,371 km from earth, 181 times as far as this probe went to mercury. Even the highest resolution earth imaging satellites we have orbit at around 500km.

    While you can't scoop up the dirt, being that close for visuals has to be nearly as good as landing there...

Slashdot Top Deals

C'est magnifique, mais ce n'est pas l'Informatique. -- Bosquet [on seeing the IBM 4341]

Close