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Astronomy Picture of the Day -- MESSENGER's First Day
NASA ^ | October 08, 2011 | (see photo credit)

Posted on 10/08/2011 8:06:16 AM PDT by SunkenCiv

Explanation: One solar day on a planet is the length of time from noon to noon. A solar day lasts 24 hours on planet Earth. On Mercury a solar day is about 176 Earth days long. And during its first Mercury solar day in orbit the MESSENGER spacecraft has imaged nearly the entire surface of the innermost planet to generate a global monochrome map at 250 meters per pixel resolution and a 1 kilometer per pixel resolution color map. Examples of the maps, mosaics constructed from thousands of images made under uniform lighting conditions, are shown (monochrome at left), both centered along the planet's 75 degrees East longitude meridian. The MESSENGER spacecraft's second Mercury solar day will likely include more high resolution targeted observations of the planet's surface features. (Editor's note: Due to Mercury's 3:2 spin-orbit resonance, a Mercury solar day is 2 Mercury years long.)

October 08, 2011

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; mercury; science
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[Credit: NASA/JHU APL/CIW]

1 posted on 10/08/2011 8:06:23 AM PDT by SunkenCiv
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To: SunkenCiv

Nice pictures though it seems like such a waste of resources since man would be incinerated if he attempted to make a landing there.

Still I have to give credit to NASA for a great picture.


2 posted on 10/08/2011 8:13:51 AM PDT by puppypusher (The World is going to the dogs.)
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To: SunkenCiv

Bush’s fault. That’s what happens when you don’t re-elect Obama and give the planet a chance to heal.....


3 posted on 10/08/2011 8:14:38 AM PDT by JusPasenThru (HEY UNION MEMBER: INVEST IN YOUR OWN DAMN INFRASTRUCTURE FOR A CHANGE!)
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To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; married21; steelyourfaith; Mmogamer; ...

4 posted on 10/08/2011 8:16:50 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: puppypusher

>>Nice pictures though it seems like such a waste of resources since man would be incinerated if he attempted to make a landing there.

Well, not really, if he landed on the back side he’d be frozen to death.

COULD YOU IMAGINE THE SUNRISE ON MERCURY THOUGH?


5 posted on 10/08/2011 8:17:32 AM PDT by struggle
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To: puppypusher

Thanks, SunkenCiv, for all your postings, which provide us with nuggets of goodness amidst the political gloom.


6 posted on 10/08/2011 8:18:07 AM PDT by bkopto (Obama is merely a symptom of a more profound, systemic disease in American body politic.)
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To: struggle

Right...so imagine the only ‘reasonably habitable’ temps would be a narrow band, running roughly north-south, where space zero meets sun melt...
I’ve always wondered what that’s like.


7 posted on 10/08/2011 8:27:38 AM PDT by spankalib
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To: JusPasenThru

Looks like the Moon, which is probably why this pic makes it look like Mercury’s mooning us.


8 posted on 10/08/2011 8:27:56 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: puppypusher

Silly, they’ll go at night.


9 posted on 10/08/2011 8:28:10 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: puppypusher
man would be incinerated if he attempted to make a landing there.

Only on the day side (mercury is tidally locked) and the right kind of thermal shielding would make a dayside landing feasible. At this point there's no reason to land but mercury is rich in heavy metals and may be prime mining territory in the distant future.
10 posted on 10/08/2011 8:30:04 AM PDT by cripplecreek (MLB Playoff thread http://www.freerepublic.com/focus/f-chat/2786167/posts)
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To: SunkenCiv

11 posted on 10/08/2011 8:31:30 AM PDT by JoeProBono (A closed mouth gathers no feet)
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To: struggle; spankalib

The day is 176 Earth days long, so, plenty of time to explore the night-side surface, given the probable length of the mission. Mercury’s one of the handful of Solar System destinations possible for human landfall.

Of course, the night-side surface will be explored by starlight. There’s no twilight, because Mercury’s got very little atmosphere, despite its density.


12 posted on 10/08/2011 8:31:45 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: bkopto

My pleasure, and thanks for the kind remarks.


13 posted on 10/08/2011 8:31:52 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: struggle

Mercury is tidally locked but there is some sun movement in the sky due to its somewhat elliptical orbit. As I understand it, near the terminator between day and night there are 3 sunrises and 3 sunsets per mercurian day for some reason.


14 posted on 10/08/2011 8:33:02 AM PDT by cripplecreek (MLB Playoff thread http://www.freerepublic.com/focus/f-chat/2786167/posts)
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To: JoeProBono

Thanks JPB! Nice link, btw.


15 posted on 10/08/2011 8:33:02 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: cripplecreek

Thanks for the MLB thread link!


16 posted on 10/08/2011 8:33:12 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: SunkenCiv

I’m going to start a new thread for the ALCS and NLCS playoffs this afternoon and will post the link in my tagline for that too.


17 posted on 10/08/2011 8:34:58 AM PDT by cripplecreek (MLB Playoff thread http://www.freerepublic.com/focus/f-chat/2786167/posts)
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To: cripplecreek

I was wrong about it being tidally locked but its got an odd orbit to axis rotation ratio. 3 days take 2 mercurian years.

http://en.wikipedia.org/wiki/Mercury_%28planet%29


18 posted on 10/08/2011 8:38:36 AM PDT by cripplecreek (MLB Playoff thread http://www.freerepublic.com/focus/f-chat/2786167/posts)
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To: cripplecreek

“Mercury’s axial tilt is almost zero,[75] with the best measured value as low as 0.027 degrees.[7] This is significantly smaller than that of Jupiter, which has the second smallest axial tilt of all planets at 3.1 degrees. This means that to an observer at Mercury’s poles, the center of the Sun never rises more than 2.1 arcminutes above the horizon.[7]

At certain points on Mercury’s surface, an observer would be able to see the Sun rise about halfway, then reverse and set before rising again, all within the same Mercurian day. This is because approximately four days before perihelion, Mercury’s angular orbital velocity exactly equals its angular rotational velocity so that the Sun’s apparent motion ceases; at perihelion, Mercury’s angular orbital velocity then exceeds the angular rotational velocity. Thus, the Sun appears to move in a retrograde direction. Four days after perihelion, the Sun’s normal apparent motion resumes at these points.[18]”

http://en.wikipedia.org/wiki/Mercury_planet#Orbit_and_rotation


19 posted on 10/08/2011 8:40:01 AM PDT by ETL (ALL (most?) of the Obama-commie connections at my FR Home page: http://www.freerepublic.com/~etl/)
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To: struggle; puppypusher; SunkenCiv
>>Nice pictures though it seems like such a waste of resources since man would be incinerated if he attempted to make a landing there.

Well, not really, if he landed on the back side he’d be frozen to death.

Are there areas where the porridge is just right?

20 posted on 10/08/2011 8:41:24 AM PDT by decimon
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To: struggle

>>Nice pictures though it seems like such a waste of resources since man would be incinerated if he attempted to make a landing there.

Well, not really, if he landed on the back side he’d be frozen to death.

COULD YOU IMAGINE THE SUNRISE ON MERCURY THOUGH?

A sunrise on Mercury would be fantastic.The only problem I see would be that your retinas would burn out from the intensity of the exposure.

As far as making a landing on the dark side of the planet you would still be exposed to the suns maximum radiation on the approach to the planet.Unless of coarse you made the trip at night.Ha,Ha,Just joking.


21 posted on 10/08/2011 8:50:15 AM PDT by puppypusher (The World is going to the dogs.)
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To: SunkenCiv

Looks about like our Moon. That’s what I thought it was at first glance.


22 posted on 10/08/2011 9:00:42 AM PDT by KoRn (Department of Homeland Security, Certified - "Right Wing Extremist")
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To: decimon

"Sunrise Over Mercury"


23 posted on 10/08/2011 9:02:05 AM PDT by JoeProBono (A closed mouth gathers no feet)
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To: JoeProBono
Looks more like From a Buick 8.
24 posted on 10/08/2011 9:05:28 AM PDT by aruanan
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To: SunkenCiv

I’d imagine the ‘darkside’ of Mercury would be preferable for exploration because it would also be well protected from the dangers that can come from the Sun. Might be an excellent place to look at mining operations.


25 posted on 10/08/2011 9:05:39 AM PDT by KoRn (Department of Homeland Security, Certified - "Right Wing Extremist")
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To: puppypusher
man would be incinerated if he attempted to make a landing there.

I saw a science documentary about Mercury, which always has the same hemisphere facing the sun.

It turns out that there is about a 60 mile temperate band running north to south, in an eternal "twilight zone" between the sun side and the dark side. According to the show, the temperature in that zone would accommodate human life.

The show was about what life would be like in a human operations base established in that zone.

It was pretty cool.

26 posted on 10/08/2011 9:10:31 AM PDT by Maceman (Obama: As American as nasei goreng)
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To: decimon

Survival on Mercury would be an engineering problem, just as it was on the Moon. The similarity with the Moon is probably very great. Mercury may have enough atmosphere to produce windstorms, which may be sandstorms somewhat analogous to those on Mars (which has an atmosphere that is very tenuous).


27 posted on 10/08/2011 9:50:17 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: ETL; cripplecreek; KoRn; Maceman; puppypusher

Thanks ETL.


28 posted on 10/08/2011 9:53:28 AM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: Maceman

Ok, possible stupid question of the day, but why are planets always round? Why not square, rectangular, lopsided, asymetrical, whatever. Why always round? An inquiring mind wants to know.


29 posted on 10/08/2011 9:54:19 AM PDT by flaglady47 (When the gov't fears the people, liberty; When the people fear the gov't, tyranny.)
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To: flaglady47

Gravity pulls all the mass toward its center. If you collected all the asteroids together into a single lumpy mass, they would eventually settle into a globe.


30 posted on 10/08/2011 10:22:41 AM PDT by cripplecreek (MLB Playoff thread http://www.freerepublic.com/focus/f-chat/2786167/posts)
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To: decimon

Perhaps it bears further investigation?


31 posted on 10/08/2011 10:37:25 AM PDT by mikrofon (Local "Goldilocks" zone)
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To: cripplecreek

In a Hermetically-sealed environment, as it were....


32 posted on 10/08/2011 10:41:23 AM PDT by mikrofon (Stopping now ;)
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To: cripplecreek

Gravity pulls all the mass toward its center. If you collected all the asteroids together into a single lumpy mass, they would eventually settle into a globe.

Aha! Brilliant, my dear Watson. Question answered. I think the same process took place on my older physique, a simple lumpy mass that has settled into a globe, lol. Thanks for the info.


33 posted on 10/08/2011 10:48:45 AM PDT by flaglady47 (When the gov't fears the people, liberty; When the people fear the gov't, tyranny.)
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To: SunkenCiv

Somewhat rugged climate, but it won’t be long before some developer builds timeshares.


34 posted on 10/08/2011 11:50:08 AM PDT by left that other site (Psalm 122:6)
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To: Maceman

I imagine the radiation on Mercury must be brutal being so close to the sun. If the radiation levels on Mars are a problem for future maned exploration imagine the levels on Mercury.


35 posted on 10/08/2011 12:28:34 PM PDT by HenpeckedCon (What pi$$es me off the most is that POS commie will get a State Funeral!)
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To: struggle

What if “he” landed at some geographic mid-point between night and day. Or is that only a theoretical mid-point that is too small for a human craft to occupy, leaving it in real time mostly on one side or the other of such a midpoint.

If more than just a small and theoretical midpoint is possible, to land at, then would it be possible to have equipment that would use the temperature differential between the two sides of the midpoint to (a) produce energy or a “heat exchange process”, for the craft and (b) sufficient to protecting the craft, inside and out, from the temperature extremes? Just a thought.


36 posted on 10/08/2011 2:31:39 PM PDT by Wuli
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To: SunkenCiv
Mercury’s hot and cold south pole
37 posted on 10/08/2011 4:17:18 PM PDT by Sawdring
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To: Sawdring; Fred Nerks

Thanks, that’s not a site I’m wildly fond of, but that’s an excellent couple of paragraphs about the differences in impact energy. Given that Mercury doesn’t seem to be differentially cratered (as Mars is — a single large impact event formed a great many of Mars’ craters, in the “hemisphere of craters”), the surface also doesn’t appear to be as cratered as it should be if the planet formed at the same time as the Earth, and/or if it formed in what is now the Inner Solar System.

Since tidal forces from the Sun push the planet (and Earth, and any other body in prograde orbit) to higher orbit, even as it sucks down the rotational energy by the same process, Mercury had to either have been born from the Sun and migrated outward, or formed further out and at some point moved in. :’)


38 posted on 10/08/2011 6:01:40 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: SunkenCiv

Why don’t you like Discover?


39 posted on 10/08/2011 6:27:26 PM PDT by Sawdring
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To: Sawdring

I meant Plaitt and his “Bad Astronomy”. He often lives up to the name though. :’)


40 posted on 10/08/2011 6:44:11 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: SunkenCiv

its most unlikely, but it looks likes vegitation at the north pole...


41 posted on 10/08/2011 6:52:16 PM PDT by sit-rep
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To: left that other site

:’) What will happen is, a startup company will get $600 million to build the timeshares, build one, and be unable to account for the rest of the money. Zero’s fault.


42 posted on 10/08/2011 6:55:45 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: sit-rep

I kinda love that deep, charcoal-lookin’ impact crater on the right hemisphere. :’)


43 posted on 10/08/2011 7:01:13 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: SunkenCiv

They will have PLENTY of solar Energy!


44 posted on 10/08/2011 7:25:56 PM PDT by left that other site (Psalm 122:6)
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To: JoeProBono

“I’m gonna buy me a Merc-rayh...”


45 posted on 10/08/2011 7:55:54 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list)
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To: aruanan

That’s not a Buick.


46 posted on 10/08/2011 7:56:40 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list)
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To: SunkenCiv

Irresistible!


47 posted on 10/08/2011 7:57:14 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list)
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To: left that other site

As long as it’s used there, I’m okay with that. :’)

If there were something that could be made into fuel using electricity on the Moon, and delivered in the same way as the titanium, it might even be an export. :’)


48 posted on 10/08/2011 7:57:55 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: left that other site

Whoops. This made much more sense when I thought I was in a different topic. [blush]


49 posted on 10/08/2011 8:01:57 PM PDT by SunkenCiv (It's never a bad time to FReep this link -- https://secure.freerepublic.com/donate/)
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To: TheOldLady
That’s not a Buick.

The car (especially the grill) reminded me of the illustration of the car on the cover of "From a Buick 8" by Stephen King.
50 posted on 10/09/2011 4:14:00 AM PDT by aruanan
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