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Mars Space Science

Mars Swings Unusually Close to Earth 335

amazon10x writes "Mars will come unusually close to the Earth on Saturday; the second time in 60,000 years. The last occurrence was in 2003. 'This is the best we're going to see Mars, so we should strike the iron while it is hot,' said Kelly Beatty, executive editor of Sky & Telescope magazine. The Red Planet will be 43.1 million miles from Earth at 11:25pm [Eastern time]." Update by J : Starting a few hours after sunset, look fairly high in the eastern sky.
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Mars Swings Unusually Close to Earth

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  • Unusual? (Score:2, Interesting)

    Usually, when you use the word "unusual", it implies a sort of unexpectedness of the event. If there was an unusual swing of Mars towards Earth, I don't think it would be minor news.
    • Re:Unusual? (Score:4, Informative)

      by laughingcoyote ( 762272 ) <barghesthowl&excite,com> on Friday October 28, 2005 @02:41AM (#13895057) Journal

      "Unusual" can also mean "rare"-I think that's the context it's used in here.

    • by WARM3CH ( 662028 )
      In galactic scales, for an event to accure only once every 60,000 year, the word is not "unusual". The correct word in these situations is "normal" or even "quite often"!.
      • by aussie_a ( 778472 ) on Friday October 28, 2005 @03:20AM (#13895161) Journal
        How about twice in 2 years, while having not occurred until 60,000 years before that?
        • by bdeclerc ( 129522 ) on Friday October 28, 2005 @06:42AM (#13895603) Homepage
          And the worst thing about this whole thing is that it isn't true!

          While in 2003 Mars passed us closer then at any other time in the last 60.000 years, it passes us by pretty close every 15 and 17 years. The 2003 passage was a "whopping" 1% closer to us than the 1971 pass, and this year's pass at 43 million miles is not unusual at all, every 15-17 years there's at least one pass that is significantly closer than that, the 1988 pass being at 37 million miles - noticably further than 2003, but much closer than this year's passage.

          So as usual, take main stream press accounts of science stuff with a very big grain of salt!
          • An it will continue to pass closer and closer until *SPLAT*.

            Haven't you noticed? 5 years ago, it would have been rare to meet 2 dense induhviduals in a week! Now, I usually encounter at least 1 a day. This accumulating density is subtly increasing the Earth's gravitational field. (Yes, yhat's also why your scale keeps going up.)

            I believe reality television is to blame. I eagerly tuned in to the first season of Survivor, thinking "Oh boy! Televised Darwin Awards!" But, wha?? They *vote* people off? The smart people? This isn't "survival of the fittest", it's survival of the weaseliest. (It is so a word, Dilbert [dilbert.com] says so and that's good enough for me!)

            And weaselness is closly related to denseness. Don't believe me? Take a minute to talk to your upper management. Then another minute to see what they get away with. See!?
          • by phlegmofdiscontent ( 459470 ) on Friday October 28, 2005 @08:36AM (#13896066)
            In addition, the article states that Earth and Mars are usually 140 million miles apart, as if they just stay stationary and only occasionally move closer. 140 million may be the average, but the separation is always changing. Seriously, this is why other countries laugh at the US, because even our science writers lack even a grade-school education in science.
        • by purfledspruce ( 821548 ) on Friday October 28, 2005 @07:12AM (#13895682)
          It's still not "unusual" -- these orbits have been known and tracked since ancient times and are fully predictable. It has to do with the different orbital velocities and the slightly eccentric orbits. The two planets will be close to each other again in 2 years and 2 months, just like always, it's just that they'll be slightly further apart the next time that we get close together.

          Imagine an egg still in its shell. Looking down at the egg, it's like the shell is the orbit of Mars and the yolk (still inside the shell, of course) is the orbit of the Earth. In 2003, when the two planets got as close as they can get, it was like both were on the wide end of the egg, where the yolk is closest to the shell. Well, Mars' orbit takes about two years and two months to complete, so this year Mars and the Earth meet up near the wide end of the egg again. In two years' time, though, Mars will be a little further along the shell of the egg when it catches up to Earth, which will be a little further from the wide end of the egg.

          In 60,000 years or so, the closest approach will have walked all the way around the edge of the egg until it's at the "closest closest approach," the wide end of the egg. There's nothing unusual about it.

        • by jridley ( 9305 )
          Yeah, except it's not true. The pass 2 years ago was closest in 60,000 years, but this one's not unusually close at all. Mars is at opposition with Earth every 2 years, and every time there's all kinds of sloppy science reporting. When I read this on CNN yesterday, I just shook my head.

          The reporting last time was ridiculous; some even stated that Mars would look as big as the moon; this again was sloppy misquoting; S&T had said that Mars IN A 75X TELESCOPE would appear as big as the Moon does TO THE
      • but we live on earth. for us, it is unusual.
    • I think "unusual" is a good word, as it's not usually this close.

      "Irregular" would be a poor choice, on the other hand. The movement of the planets is quite regular.
  • Time zone? (Score:5, Insightful)

    by lisany ( 700361 ) <slashdot.thedoh@com> on Friday October 28, 2005 @02:41AM (#13895055)
    Well what time zone? 11:25pm here could be 6:25am somewhere else. Bad slashdot!
    • Re:Time zone? (Score:5, Informative)

      by mmjb ( 866586 ) on Friday October 28, 2005 @02:59AM (#13895113)
      From TFA:
      On Saturday, Mars' orbit will bring it 43.1 million miles away from Earth, with its closest pass scheduled for 11:25 p.m. EDT.

      EDT is 4 hours behind of Coordinated Universal Time (UTC), ergo closest orbit will be at 03:25 a.m. UTC.

      I think.
    • Re:Time zone? (Score:3, Informative)

      by m50d ( 797211 )
      No true geek would use anything but UTC, wherever you are.
      • Re:Time zone? (Score:3, Interesting)

        by pv2b ( 231846 )
        No true geek would use anything but UTC, wherever you are.

        No.

        A true geek would know all the different ways employed to measure time, included, but not limited to, the various different variations of Universal Time, Atomic Time, Solar Time, Sidereal Time, Ephermis Time and Terrestrial Time, not to mention time according to the day/night cycle of an extra-terrestrial body. He would also be able to tell you in minute detail the differences between GMT and UTC.

        Time zones are easy, they're all just simple offset
    • Right, but anywhere you are in the world, at 11:25, you'll be facing more or less towards the outside of the solar system. The closest you would ever get to mars, assuming perfectly circular orbits would be at 12:00 midnight with mars directly along the vector perpendicular to the tangent of Earth's path. So at 11:25 no matter where you are in the world, you could be the closest to mars. Now it might be that lateral distance is much more important than the distance gained by being on the correct side of
    • Re:Time zone? (Score:5, Informative)

      by Dwonis ( 52652 ) * on Friday October 28, 2005 @08:49AM (#13896140)
      The earth is spherical, and it rotates. (!)

      When it's 11:25 PM wherever you are, that's the time to look.

    • Maybe... (Score:3, Informative)

      by Greyfox ( 87712 )
      11:25PM in EVERY timezone! After all, it doesn't do much good to look while the sun's still up!

      Use as directed. Comment not valid in Canada or either of the two poles. Author not responsible for alien abductions due to stargazing.

  • What time zone is that time in?

  • This time around it will be not so close to the horizon when it is visable, look to the west, it will be the brightest object in the sky.
  • Re: (Score:2, Insightful)

    Comment removed based on user account deletion
    • Re:Wow. (Score:4, Funny)

      by ozmanjusri ( 601766 ) <aussie_bob.hotmail@com> on Friday October 28, 2005 @03:39AM (#13895221) Journal
      Given advances in technology by that point, it should make a great time to put men on Mars.

      How long will we have to wait intil we're advanced enough to put women there as well?
    • Given advances in technology by that point, it should make a great time to put men on Mars.

      I mentioned this elsewhere in this article, but I'll repeat it here too since it's relevant.

      While that is indeed considerably closer than it would be on the average random day, every couple of years Mars gets within about 49 million miles of Earth. This event's 43.1 million miles, while smaller than usual, doesn't represent an amazingly rare 4x difference.

      • Re:Wow. (Score:5, Informative)

        by macpeep ( 36699 ) on Friday October 28, 2005 @04:16AM (#13895293)
        Exactly. And even more importantly for Mars missions and such is that the energy / velocity required to get to Mars varies hardly at all between the every couple of year distance of 49 million miles vs. this year's 43.1 million miles. It's easier to visualize if one understands that one doesn't fly in a straight line to Mars from Earth. That is, to fly from Earth to Mars today, you wouldn't travel 43.1 million miles just because that's the distance today. Rather, you'd travel something like 500 million miles cause you'd fly in a so called Hohman transfer orbit that essentially traces an elliptical orbit that has a periapsis (closest to sun) point that touches Earth's orbit and apoapsis (furthest from the sun point that touches Mars' orbit. The distance of the arc of that orbit between the periapsis and apoapsis is very roughly 500 million miles and varies VERY little depending on how close Mars was to Earth at launch time. And equally small is the variation in flight time and required fuel, thrust and delta velocity.

        Peppe
    • Re:Wow. (Score:3, Insightful)

      Given advances in technology by that point, it should make a great time to put men on Mars.

      This makes virtually no difference to the effort required to transfer an object to Mars from Earth. The orbit would be an elliptical transfer orbit (the most efficient), and is far more dependent on the position of Mars relative to Earth (hence "launch windows" for probes).

      The 7ish million miles will make naff all difference - the point is actually when someone will stump up the cash, and when we figure out how

    • So this date in 2018 is a great time to put people on Mars... but what about getting them back? does that mean they've got to wait there for 13/50/ 10,000 years before they can come back.... errr.... I sense a problem here....
      • by Yakman ( 22964 ) on Friday October 28, 2005 @04:48AM (#13895356) Homepage Journal
        but what about getting them back?

        Who says it has to be a return mission? Come on, don't you think there would be plenty of qualified volunteers for a one way mission? This is why I think China will be space pioneers (well, 2nd generation pioneers) - because they will be able to launch one way missions without too many naysayers complaining about it.
        • by idlake ( 850372 )
          The Chinese government does not want to go down in history as a government that sends people to their death in interplanetary travel; it's bad PR, it's bad for business, and it doesn't even fit in with the philosophy underlying Chinese governmental authority.

          In any case, what would the motivation be? The only reason for manned travel to Mars in the near future is as a publicity stunt and to make people believe that the universe works like it does in Star Trek. That illusion is going to be destroyed if you
  • Time Zone (Score:4, Informative)

    by acd294 ( 685183 ) on Friday October 28, 2005 @02:46AM (#13895075) Homepage
    For those like me wondering the time zone, I actually RTFA:

    On Saturday, Mars' orbit will bring it 43.1 million miles away from Earth, with its closest pass scheduled for 11:25 p.m. EDT.
    • Re:Time Zone (Score:3, Informative)

      by merdaccia ( 695940 )

      And just to further confuse the crap out of people, at 11:25pm Eastern Daylight Time, Europe will be in Winter time, having changed its clocks just a few hours before. So 23:25 EDT will be 03:25 GMT, not the typical 04:25 GMT.

      Either way, it's on Saturday night. I'll have trouble seeing my feet, let alone Mars.

      • What?! GMT doesn't change with the seasons, GMT == UTC == Zulu for all intents and purposes. Infact, I don't know of any timezones that change during the year - people switch to seasonal timezones, but the timezones themselves don't change.

        • Re:Time Zone (Score:3, Insightful)

          by evilandi ( 2800 )
          Correct. I'm a Brit in the UK; today Friday 28 October we are in BST (British Summer Time) which is GMT+1. It will remain BST tomorrow Saturday.

          At 3AM BST Sunday morning, it will become 2AM GMT. It will then be GMT through to the last Sunday in March.

          This is even more annoying than usual, because we are using Windoze laptops on a ghost hunt overnight Saturday night / Sunday morning. We are expecting very annoying data logging problems at 2AM BST/3AM GMT as Windoze automatically switches timezone. Which is w
          • I wrote: problems at 2AM BST/3AM GMT

            Correction: 3AM BST/2AM GMT. See how confusing it is? We really should have picked a better night for the investigation.
          • Switch the laptops to Casablanca time - it's the same as GMT without the BST switch.

            Or you could just un-tick the 'auto adjust for daylight savings' checkbox until you've done the ghost hunt?

            -Jar.
            • Or you could just un-tick the 'auto adjust for daylight savings' checkbox until you've done the ghost hunt? ...and if Windoze still cocks up we can call it evidence of paranormal intervention! Result!
          • "We are expecting very annoying data logging problems at 2AM BST/3AM GMT as Windoze automatically switches timezone. Which is why I'm recommending we use a Linux laptop which has been forced to GMT hardware clock."

            Are you sure that is your only option?

            Is there a ghost of a chance that your recommendation will acted apon?

            Boom-Boom! Thankyou, I'll be here all night.
      • Re:Time Zone (Score:2, Informative)

        by sheppos ( 633308 )
        Actually, GMT doesn't change, the UK for instance is currently using BST which is GMT+1. On Saturday we switch back to using GMT.
    • pass scheduled for 11:25 p.m. EDT.

      I'm still wondering. I have no idea how many hours from GMT EDT would be. I am not even sure that there are not multiple zones that use the EDT acronym. Like Eastern Dagestan Time, or something.
      • I'm still wondering. I have no idea how many hours from GMT EDT would be. I am not even sure that there are not multiple zones that use the EDT acronym. Like Eastern Dagestan Time, or something.

        It'd be rather more useful if times were quoted in UTC or with a quoted offset rather than using a (to most of the world) fairly meaningless acronym...
    • by squoozer ( 730327 ) on Friday October 28, 2005 @04:03AM (#13895272)

      This is obviously a Martian invasion plan. First they submit a story to /. that doesn't contain the timezone which confuses us a bit. Then they choose a time zone that plenty of people don't know (judging by the other comments). Then, and this is the one that really convinced me it's an invasion, they make sure that the conversion from the given timezone to to the ones used in Europe is as difficult as possible (most of Europe switches from daylight savings time to standard time on that night). This is a cunning ploy to keep us on the back foot while they get their ships of death in place. It should be evidence enough for any one.

      To arms, the Martians are coming.

      P.S. There are some dubious looking bumps in the sand on Mars. I think they might be hiding WMDs!

  • All this (Score:2, Insightful)

    damn light pollution! Looks like a good excuse for a road trip.
  • The Distance... (Score:3, Informative)

    by CrackedButter ( 646746 ) on Friday October 28, 2005 @02:48AM (#13895078) Homepage Journal
    is so close, yet so far!
  • Getting closer! (Score:3, Insightful)

    by e.loser ( 923789 ) <{moc.liamg} {ta} {ermah.nosaj}> on Friday October 28, 2005 @02:50AM (#13895085)
    Second time in 60,000 years that we know of? If the last time it happened was in 2003, and this is only 2 years later, and the next time is "scheduled to be in 2018 (FTFA)", is it possible we just didn't have the technology to detect it back then?
  • From article (Score:5, Informative)

    by smeenz ( 652345 ) on Friday October 28, 2005 @02:51AM (#13895090) Homepage
    As I know nobody will actually read the article, I'll summarise it here:

    It won't be as close as it was in 2003, but it will be more visible to more of the earth's population
    This is the closest it will be until 2018
    Hubble will be snapping party photos of it for posterity's sake.
    Also, here's a diagram showing the realtime orbits of the inner planets [fourmilab.ch] so you can see for yourself.
  • once per 60'000? (Score:3, Interesting)

    by Janek Kozicki ( 722688 ) on Friday October 28, 2005 @02:57AM (#13895103) Journal
    second time in 60,000 years. The last occurrence was in 2003.

    So the event that happens once per 60,000 years - happens now a SECOND time, just after two years?

    No (the summary is of course poorly written), in 2003 it was 35 million miles (56 000 000 km), and then it was an event once per 60,000 years. Now it is 43.1 million miles (69 000 000 km) and it is an event once per .... oops I don't know. But it happens more often ;)
  • by dascandy ( 869781 ) <dascandy@gmail.com> on Friday October 28, 2005 @03:00AM (#13895116)
    The information in the article in SI units:

    > On Saturday, Mars' orbit will bring it 69.4 million kilometers away from Earth, with its closest pass scheduled for 3:25 p.m. UTC.

  • Mars feels it comes "unusually close to the Earth". Like in "Since a couple of years I feel irresistibly attracted to Earth." Or like suddenly Mars' orbit has changed.

    Just bear in mind that 60k years is a fart in planetary history. This coming close to Earth could have -or has been- predicted hundreds of years ago.
  • Hunker Down (Score:4, Funny)

    by chkMINUS ( 910577 ) on Friday October 28, 2005 @03:10AM (#13895141)
    With all the natural disasters lately, I'm stocking up on food and water in case it hits.
  • by troon ( 724114 ) on Friday October 28, 2005 @03:20AM (#13895162)

    ...and they want their geocentric theory back...

    From TFA: The two planets -- normally separated by about 140 million miles -- will not be this close again until 2018.

    Normally separated by 140 million miles? On average, Earth orbits at 93m miles, Mars at 140m miles, both roughly on the same plane. That means the distance will vary periodically from around 230m miles to 47m miles. This current phenomenon is a "minimum minimum" which is why it is notable.

    It sounds like CNN looked up the orbital distance from Mars and assumed that it orbits the Earth...

  • War!!! (Score:2, Funny)

    by BarryNorton ( 778694 )
    Don't tell me this, just as I'm (re-)reading War of the Worlds!
  • people please (Score:5, Informative)

    by macpeep ( 36699 ) on Friday October 28, 2005 @03:51AM (#13895246)
    We all went to school and we all know how this works. Let's just calm down and consider how rare or not rare this event is.

    Earth orbits the sun in a nearly circular orbit at a mean distance of 1 astronomical unit (by definition of AU). Mars on the other hand orbits the sun in a less circular orbit that takes it as far as 1.67 and as close as 1.38 astronomical units from the sun. As we all know, it takes earth 1 year to orbit the sun (again, by definition of a year). It takes Mars 687 days (1.88 earth years).

    Let's put this into more "human" terms using an analogy. Let's imagine a rock in the middle of a field. And let's put two people walking in circles around the rock. One person at a distance of 10 meters and the other at a distance that varies between 14 and 17 meters from the rock. Very quickly we'll notice that the closest the people can ever come from eachother is 4 meters and the furthest they can come is 27 meters. But we also notice that as they walk around, the person closer to the rock will take 1 minute to walk around the rock and the person on the outside will take 1.88 mintues so the one on the inside will be overtaking the one on the outside roughly every other minute (once per two years in Mars-Earth terms). And whenever they overtake, the distance will be anything from 4 to 7 meters. And quite often, it will be a distance of 4 to 5 meters or so. It's not rare at all. What's rare is that it would be VERY close to the minimum 4 meters.

    So.. when we say it's "amazingly close" and "closer than in 60000 years", it's more like getting within 4.1 meters instead of 4.25 in the analogy above. We're not talking about 4 meters vs. 27 meters or anything like that.

    Conclusion: this isn't THAT special at all. Mars isn't THAT much closer at all. For example for Mars missions and such, the difference in distance is mostly irrelevant.

    Peppe
    • When I say that the difference in distance is mostly irrelevant, I meant the difference in distance of the closest approach - which happens roughly every two years. It doesn't matter much in terms of delta velocity if the distance from Earth to Mars is 0.38 or 0.42 astronomical units. It would matter much if the distance is 0.4 or 2.5 AU though, but that's irrelevant since missions to Mars are only started when the two planets are close to the closest approach. And that's no rare event at all - it happens o
  • Doom (Score:5, Funny)

    by MacGod ( 320762 ) on Friday October 28, 2005 @04:14AM (#13895289)
    This is just so the demons can use those teleport pads to beam themselves to Earth. Here's hoping that by the time they arrive, we've figured out how to hold a flashlight AND a gun!
    • > This is just so the demons can use those teleport pads to beam themselves to Earth. Here's hoping that by the time they arrive, we've figured out how to hold a flashlight AND a gun!

      No problem, I always shoot with my eyes closed.
    • Re:Doom (Score:3, Funny)

      by trongey ( 21550 )
      Forget the flashlight. Somebody's gotta get busy scattering boxes of shotgun shells all over the place! Well, that and developing body armor that automatically jumps off of the ground and puts itself on you when you step on it.
      But what about the Leather Goddesses?
  • Yes, under the name Ares he bonked Venus (aka Aphrodite), the wife of Vulcan (Hephaestos), who, having his suspicions, set up a trap and caught them at it in bed with a net, and then called all the other Olympians in to see his catch, and -

    Ok, I guess porn wasn't read for the quality of the plots way back then either.
  • The attraction between earth and mars is then

    6.67*10^-11*6*10^24*6.4*10^23/(54*10^9)^2 = 8,7*10^16 Newton
    (metric units)

    it seems a large number but if you see the mass of the earth 6*10^24 it means every kg recives a force of 1,5*10^-8 Newton.

    My weight is about 80 kg it means the mars attracts me with 1,2*10^-6 N what is about 0,12 mg.

    Just to get some idea of relations...
  • "Seeing it clearly" is much more dependent on the distance through the atmosphere you have to look through. The distance to Mars is only a teensy, tiny, itsy-bitsy, microscopically shorter right now.

    To see Mars most clearly you should wait until it's as high above the horizon as possible, not until it's a wee bit closer.

  • by ChrisCampbell47 ( 181542 ) on Friday October 28, 2005 @10:54AM (#13897022)
    I am so tired of this story. Every 22 months it comes back and I have to explain it to all the non-technical members of my extended family who ask me about it, expecting a freaking flash in the sky or a moon sized UFO or some crazy crap like that.

    Think about this: all of these people are voters. Now extrapolate to environemental policies, energy issues, stem cell research ...

    Freedom is on the march!

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