Curiosity Rover Sees Solar Eclipse On Mars

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Curiosity Rover Sees Solar Eclipse On Mars

Posted by samzenpus on Monday September 17, 2012 @01:14AM from the differenet-view dept.

SchrodingerZ writes "Though solar eclipses are fairly common on Earth (much more in the southern hemisphere), yesterday the Mars Curiosity Rover caught sight of a partial solar eclipse in Gale Crater on the Red planet. The martian moon Phobos took a small bite out of the sun on the 37th day (Sol 37) of the rover's martian mission. The Curiosity Rover was able to take a picture of the rare event through a 'neutral density filter that reduced the sunlight to a thousandth of its natural intensity.' This protects the camera from the intense light rays seen during an eclipse or looking directly at the sun. It is possible a short movie of the event could be compiled from the data in the near future. More solar transits of Mars's moon (including the second moon Deimos) are predicted to happen in the days to come."

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An eclipse is NOT more common in S. hemishere by Sir_Kurt · 2012-09-17 01:31 · Score: 5, Interesting

I don't know where the submitter or editor got his/her eclipse frequency info, but the chances of an eclipse occuring are equal for both hemispheres. If you look at a specific short enough time span, it may appear to favor one hemisphere over another, but the eclipse geometry is symmetrical. There are times that a total eclipse vs. an annular eclipse will favor one hemisphere over another because the distance of the earth from the sun varies, but over any reasonable time scale this will all average out.
Kurt
1. Re:An eclipse is NOT more common in S. hemishere by slashmydots · 2012-09-17 01:33 · Score: 2, Funny
  
  You forgot to factor in the ancient mayan priest ghosts that can control the eclipses at will.
2. Re:An eclipse is NOT more common in S. hemishere by ArsenneLupin · 2012-09-17 01:45 · Score: 3, Funny
  
  More importantly, you forgot that we don't have any infinite time scale to average on, because the world only exists since a finite amount of time, and will stop existing on December 21st later this year. And during this finite timespan, the southern hemisphere did have noticably more solar eclipses!
3. Re:An eclipse is NOT more common in S. hemishere by hvm2hvm · 2012-09-17 02:44 · Score: 1
  
  I didn't bother to do some math on this but I'm pretty sure the odds even out after a few hundred years...
  
  --
  ics
4. Re:An eclipse is NOT more common in S. hemishere by hvm2hvm · 2012-09-17 02:45 · Score: 1
  
  I meant number of occurences
  
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  ics
5. Re:An eclipse is NOT more common in S. hemishere by Anonymous Coward · 2012-09-17 02:47 · Score: 0
  
  It is probably the submitter's pet theory to reconcile the facts that solar eclipses are fairly common on Earth, and that he never sees one.
6. Re:An eclipse is NOT more common in S. hemishere by Anonymous Coward · 2012-09-17 02:59 · Score: 0
  
  woosh!
7. Re:An eclipse is NOT more common in S. hemishere by fatphil · 2012-09-17 05:12 · Score: 1
  
  Looking at one single saros cycle that's only part way through its life:
  http://eclipse.gsfc.nasa.gov/SEsaros/image/Saros145-big.JPG
  it seems to take just over 100 years to go from grazing the top of the earth (1891) to peaking in central europe (lat 47-ish, sin(47)=0.73) and another just over 50 years to peak in saudi arabia (lat 25-ish, sin(25)=0.42). Alas the latitude doesn't take into account the tilt of the earth, so it's hard to extrapolate to find out when the eclipse will be centred at the equator, and subsequently reach the opposite pole. However, I wouldn't be surprised if a saros cycle lived for 500-ish years. In that time, every latitude will have been touched approximately equally, as there'll be as many new ones starting at one pole as there are ending at the other pole.
  
  Of course, there's probably a known figure for the life of a saros cycle's eclipse activity, I just haven't found it with a quick google. But anyway, such a cycle is plenty plenty of time for it to even out, so I'm sure it's true with a span of only a couple of hundred years too, so you didn't really need to reword your claim.
  
  --
  Also FatPhil on SoylentNews, id 863
8. Re:An eclipse is NOT more common in S. hemishere by fatphil · 2012-09-17 05:29 · Score: 1
  
  http://eclipse.gsfc.nasa.gov/SEsaros/SEsaros.html :
  "Saros 136 will produce 71 eclipses over 1262 years in the following order: 8 partial, 6 annular, 6 hybrid, 44 total, and 7 partial. "
  
  From: http://eclipse.gsfc.nasa.gov/SEsaros/image/SEpanoramaGvdB-big.JPG
  it seems that most cycles have about 50 annular/hybrid/total eclipses, so that would be 900 years of activity.
  
  --
  Also FatPhil on SoylentNews, id 863
9. Re:An eclipse is NOT more common in S. hemishere by gsslay · 2012-09-17 22:18 · Score: 1
  
  Well the introductory sentence is a all wrong anyway, Currently it starts off discussing how common eclipses are on Earth, which makes no sense at all. What does the the frequency of eclipses on Earth have to do with anything, unless it is used as a comparison to those on Mars? But that comparison never appears. We still don't know how common they are on Mars,
  So perhaps it should say
  "Though solar eclipses are fairly common on Mars (much more in the southern hemisphere)......"
Mar's moon? by Anonymous Coward · 2012-09-17 01:35 · Score: 5, Funny

What is this Mar they are speaking about?
1. Re:Mar's moon? by Anonymous Coward · 2012-09-17 02:19 · Score: 0
  
  What is this Mar they are speaking about?
  Well... the only Mar I know of is Andrew Mar, who is a BBC journalist.
  But I can't imagine he has his own moons. He's not that big.
2. Re:Mar's moon? by RaceProUK · 2012-09-17 02:41 · Score: 1
  
  Andrew Marr
  FTFY, and spoiled the joke too I guess.
  
  --
  No colour or religion ever stopped the bullet from a gun
Mars' not Mar's by Anonymous Coward · 2012-09-17 01:37 · Score: 0

Just wanted to say.
1. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 01:47 · Score: 1
  
  Actually, it's "Mars's". Just because it ends in 's' doesn't mean you treat it like a plural when making it possessive.
2. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 01:49 · Score: 0
  
  Actually Mars's, since Mars is not a plural.
  (There's also a dubious exception for proper nouns ending with two 's' sounds, such as Moses->Moses' or Isis->Isis', but Mars doesn't qualify, and that rule's silly anyway).
3. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 02:11 · Score: 4, Interesting
  
  Actually, it does, depending upon whose style manual you are using. In some style manuals, proper names ending with a single "s" take the possessive as "s'" and not "s's" for reasons of euphony; but in all style manuals, proper names ending with a double "ss" take the possessive as "ss's."
4. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 02:23 · Score: 0
  
  I think we can all agree it's definitely not Mar's.
5. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 04:33 · Score: 0
  
  I think you're making this up. The correct possessive form of a word that ends in 's' is:
  
  Mars’
6. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 06:15 · Score: 0
  
  Fortunately, /. is not any sort of publication that would mandate a particular style guide, so while posting here we can completely disregard any style guide which tells us to break the language in illogical ways "for reasons of euphony". Universally accepted rules might get a pass, but when there's widespread disagreement, choose the logical option.
7. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 07:58 · Score: 0
  
  Agnosticism is the only logical option, as it is the only option that can be defended on logical grounds.
8. Re:Mars' not Mar's by Anonymous Coward · 2012-09-17 20:37 · Score: 0
  
  In school English lessons, we learned that it should be
  Mars' Moon
  i.e.: put the apostrophe there, but not an additional s.
Eclipse, or transit? by Anonymous Coward · 2012-09-17 01:41 · Score: 5, Insightful

I thought we only called it an eclipse when the occluding body is of comparable angular diameter? Phobos is something like half the solar diameter (depending on latitude); I'd call it a transit.
1. Re:Eclipse, or transit? by Charliemopps · 2012-09-17 01:59 · Score: 5, Funny
  
  And you're probably the same asshat that declassified Pluto as a planet.
2. Re:Eclipse, or transit? by Anonymous Coward · 2012-09-17 01:59 · Score: 2
  
  I don't know what the official rules are for the nomenclature; however how about making it this: if the observer is on a body and the occlusion is caused by a moon of said body it is an eclipse. If the occlusion is viewed from space or is caused by a body that is not orbiting the body on which the observation occurs, call it a transit.
3. Re:Eclipse, or transit? by Anonymous Coward · 2012-09-17 02:19 · Score: 0
  
  In a lunar eclipse, the occluding body is the earth. The earth is not of comparable angular diameter as seen from earth. It is not even of comparable angular diameter as seen from the moon.
4. Re:Eclipse, or transit? by mbone · 2012-09-17 05:24 · Score: 1
  
  Yes, properly these are transits, not partial eclipses.
5. Re:Eclipse, or transit? by mbone · 2012-09-17 05:31 · Score: 1
  
  Eclipse : nearer body covers the other body
  Partial eclipse : the body could cover the other body, but doesn't (i.e., it nicks it).
  Transits : the nearer body is not big enough to cover the other body. Phobos and Deimos, as seen from the surface of Mars, fall in this category.
  The angular size of the Moon is so close to that of the Sun, as seen from the Earth, that a special kind of transit is possible, which has a special term - an annular eclipse, where a thin ring of the Sun's surface is still visible (because the Moon is near apogee, and far enough away to not fully cover the Sun). This is a special case; the term annular eclipse has a long history, and I have never heard it used to describe any other kind of transit.
SW Reference by Anonymous Coward · 2012-09-17 01:52 · Score: 0

That's No Moon!!
Not Fair by Anonymous Coward · 2012-09-17 01:56 · Score: 0

I've been on earth for how many years and I've only seen a couple. Curiosity has only been on Mars for like a month and it's already seen one. By next month it'll have seen 2. In a year it will have seen 12.
Eclipses viewed from MER by Geoffrey.landis · 2012-09-17 01:56 · Score: 3, Informative

Every location on Mars gets an eclipse by both Phobos and Deimos twice a year.
It's nice that Curiosity is looking into the sky, but it's worth pointing out that this is by no means the first time we've watched eclipses from the surface of Mars-- we've caught both Phobos and Deimos transiting the sun, from both of the the MER rovers:
Spirit http://www.lpl.arizona.edu/~lemmon/mer/phobos_transit_104a.gif
and Opportunity http://www.lpl.arizona.edu/~lemmon/mer/Phobos_Sol45B.gif
A nice page from 2006 is here: http://www.bibalex.org/eclipse2006/MarsEclipses.htm

--
http://www.geoffreylandis.com
1. Re:Eclipses viewed from MER by Anonymous Coward · 2012-09-17 02:27 · Score: 3, Informative
  
  Every location on Mars gets an eclipse by both Phobos and Deimos twice a year.
  You can't even see Phobos from the polar regions (> 70 degrees or so) -- it's always below the horizon -- so how can it eclipse anything?
  And the morons mod your crap to +4... gotta love /.
2. Re:Eclipses viewed from MER by Anonymous Coward · 2012-09-17 02:42 · Score: 5, Informative
  
  A nice page from 2006 is here: http://www.bibalex.org/eclipse2006/MarsEclipses.htm
  
  Every location on Mars gets an eclipse by both Phobos and Deimos twice a year.
  Dude, re-read your link.
  
  A nice page from 2006 is here: http://www.bibalex.org/eclipse2006/MarsEclipses.htm
  "The two moons pass between Mars and the Sun so frequently that solar eclipses would not be a rare event to the Martian observer. Phobos eclipses the Sun 1,300 times a year; but the eclipses are so brief, lasting about 20 seconds!"
  "As the orbits of Phobos and Deimos lie near the plane of Mars' equator, and due to the proximity of the moons to Mars, Phobos (and its eclipses) cannot be seen above Martian latitude 69, and Deimos (and its eclipses) cannot be seen above latitude 82."
3. Re:Eclipses viewed from MER by mbone · 2012-09-17 05:23 · Score: 1
  
  Every location on Mars gets an eclipse by both Phobos and Deimos twice a year.
  No, only at the equator :
  
  There is a narrow band, centered on the equator of Mars, within which every point is eclipsed at least once during each semiannual eclipse season. Outside that band, the density of coverage decreases slowly with increasing distance from the equator, until the limiting latitudes are reached.
  
  BTW, a surface transit (that is a more appropriate proper term, as neither moon ever fully eclipses the Sun) was also observed by the VIking Lande 1 in the 1970's.
  And for the Earth solar eclipses, over an 18.6 year cycle, are equally likely in either terrestrial hemisphere.
4. Re:Eclipses viewed from MER by Geoffrey.landis · 2012-09-17 05:51 · Score: 1
  
  You can't even see Phobos from the polar regions (> 70 degrees or so) -- it's always below the horizon -- so how can it eclipse anything?
  OK, good point. You get transits (eclipses) at every place on the surface of Mars from which you can see the moons.
  No transits of Phobos from locations where you can't see Phobos.
  
  --
  http://www.geoffreylandis.com
Moon? by mu51c10rd · 2012-09-17 02:18 · Score: 0

That's no moon...
PHOBOS by Iniamyen · 2012-09-17 02:46 · Score: 2

Did anyone else read "Phobos" in the Quake 3 Arena guy's voice?
itty bitty moons by Quiet_Desperation · 2012-09-17 03:12 · Score: 2

Aren't *all* eclipses of Mars partial?
1. Re:itty bitty moons by Anonymous Coward · 2012-09-17 03:33 · Score: 0
  
  Depends how long your ladder is.
2. Re:itty bitty moons by Hatta · 2012-09-17 03:37 · Score: 1
  
  Depends on whether you consider an annular eclipse to be partial or not.
  
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  Give me Classic Slashdot or give me death!
3. Re:itty bitty moons by doti · 2012-09-17 05:09 · Score: 1
  
  relevant:
  http://allaboutjeff.wordpress.com/2009/05/03/the-distance-of-the-moon-by-italo-calvino/
  
  --
  factor 966971: 966971
Re:Science? by camperdave · 2012-09-17 05:53 · Score: 2

Just because you find it a lame, artsy shot, doesn't mean that science isn't happening. Oh, and like it or not, the only way NASA is going to get funding for future missions is by mass market appeal, and that means lame, artsy shots.

--
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In Soviet Russia... by CohibaVancouver · 2012-09-17 08:36 · Score: 1

Sun take bite out of Phobos!
Re:Science? by cynyr · 2012-09-18 12:25 · Score: 1

yep, wouldn't want to test out the instruments before getting to the good place to make sure they are in good working order. Also who says the rover paused for more than a few seconds to tale this shot. Adjust arm while moving, pause to take shot, continue moving while parking arm again.

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