IPB

Welcome Guest ( Log In | Register )

31 Pages V  < 1 2 3 4 > »   
Reply to this topicStart new topic
MESSENGER News Thread, news, updates and discussion
Guest_Sunspot_*
post Jun 1 2005, 08:40 AM
Post #16





Guests






http://messenger.jhuapl.edu/news_room/pres...se_5_31_05.html

"NASA’s Mercury-bound MESSENGER spacecraft – less than three months from an Earth flyby that will slingshot it toward the inner solar system – successfully tested its main camera by snapping distant approach shots of Earth and the Moon."
Go to the top of the page
 
+Quote Post
um3k
post Jun 1 2005, 05:01 PM
Post #17


Member
***

Group: Members
Posts: 331
Joined: 2-May 05
Member No.: 372



No focusing problems on this baby! cool.gif
Go to the top of the page
 
+Quote Post
lyford
post Jun 1 2005, 06:30 PM
Post #18


Senior Member
****

Group: Members
Posts: 1264
Joined: 18-December 04
From: San Diego, CA
Member No.: 124



I always enjoy these far off shots of Earth. They really drive home how BIG space is and how SMALL our home is...

Anybody seen a higher rez version?


--------------------
Lyford Rome
"Zis is not nuts, zis is super-nuts!" Mathematician Richard Courant on viewing an Orion test
Go to the top of the page
 
+Quote Post
paxdan
post Jun 1 2005, 07:43 PM
Post #19


Member
***

Group: Members
Posts: 557
Joined: 29-March 05
Member No.: 221



QUOTE (lyford @ Jun 1 2005, 07:30 PM)
I always enjoy these far off shots of Earth.  They really drive home how BIG space is and how SMALL our home is...

Anybody seen a higher rez version?
*


i think this is the highest we are going to get without image processing.

from the article:

The image is cropped from the full MDIS image size of 1024x1024 pixels
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Jun 1 2005, 07:49 PM
Post #20





Guests






QUOTE (RNeuhaus @ Jun 1 2005, 02:48 AM)
Is Mercury's atmosphere similar to Moon rather than Mars? What is the composition of Mercury's atmosphere (hellium, hydrogen, oxygen, potassium and sodium)? Wiill the Messenger spacecraft  answer these questions?
*


It will indeed provide a great deal of additional information on Mercury's atmosphere -- which is incredibly rarified and thus similar to the Moon's atmosphere rather than Mars'. Indeed, both worlds actually have what is described as an "exosphere" -- from which the atoms and molecules escape almost immediately -- rather thann any stable atmosphere. Its surface density is only about one trillion atoms per cubic centimeter. (I'd have to look this up -- I haven't been following the discoveries regarding Mercury's atmosphere closely -- but I think this is an atmospheric density roughly a trillionth of Earth's.)

We also have confirmed recently that Mercury's exosphere contains small amounts of calcium. The exosphere seems to come from atoms "sputtered" off Mercury's surface rocks by the impacting atoms of the solar wind -- a phenomenon much more intense on Mercury than on the Moon, thanks to its closer proximity to the Sun -- and it is suspected that Mercury's magnetic field focuses this activity so that much of the sputtering occurs near the planet's poles.

Messenger's "Mercury Atmospheric and Surface Composition Spectrometer" really consists of two separate, entirely different instruments that might as well count as two separate experiments; they have little to do with each other. Its near-infrared spectrometer will map surface mineral composition, while its ultraviolet spectrometer will specialize in measuring the density, distribution and composition of the exosphere. (I don't know whether it can measure calcium, but I suspect it can -- and one of its goals will be to try to identify additional elements in the atmosphere, such as magnesium, silicon and sulfur.) Messenger's "Energetic Particle and Plasma Spectrometer" also has some ability to directly detect different elements' ions by mass spectrometry -- again, I'd have to do some digging for the details.
Go to the top of the page
 
+Quote Post
Bob Shaw
post Jun 2 2005, 09:00 PM
Post #21


Senior Member
****

Group: Members
Posts: 2488
Joined: 17-April 05
From: Glasgow, Scotland, UK
Member No.: 239



Bruce:

Can Messenger's instruments detect He on the surface of Mercury? I'm thinking of those old lunar He3 strip-mining plans...

Bob Shaw


--------------------
Remember: Time Flies like the wind - but Fruit Flies like bananas!
Go to the top of the page
 
+Quote Post
JRehling
post Jun 3 2005, 12:53 PM
Post #22


Senior Member
****

Group: Members
Posts: 1572
Joined: 20-April 05
Member No.: 321



QUOTE (Bob Shaw @ Jun 2 2005, 02:00 PM)
Bruce:

Can Messenger's instruments detect He on the surface of Mercury? I'm thinking of those old lunar He3 strip-mining plans...

Bob Shaw
*


In principle, He can be detected (quite easily, in fact), but that would only be if it existed in bulk concentrations, which it certainly will not. Lunar Prospector showed no He signal I'm aware of on the Moon. The quantity just isn't much to speak of.
Go to the top of the page
 
+Quote Post
Buck Galaxy
post Jun 4 2005, 02:46 AM
Post #23


Junior Member
**

Group: Members
Posts: 24
Joined: 6-March 05
Member No.: 185



QUOTE (JRehling @ Jun 3 2005, 12:53 PM)
In principle, He can be detected (quite easily, in fact), but that would only be if it existed in bulk concentrations, which it certainly will not. Lunar Prospector showed no He signal I'm aware of on the Moon. The quantity just isn't much to speak of.
*



Huh? I thought the moon's regolith was full of He3?
Go to the top of the page
 
+Quote Post
Phil Stooke
post Jun 4 2005, 03:05 AM
Post #24


Senior Member
****

Group: Members
Posts: 5726
Joined: 5-April 05
From: Canada
Member No.: 227



Buck Galaxy said:

Huh? I thought the moon's regolith was full of He3?



No - it has minute amounts of He3. Major strip-mining would be needed to collect the amounts needed for the proposed power schemes.

Phil


--------------------
... because the Solar System ain't gonna map itself.
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Jun 4 2005, 05:55 AM
Post #25





Guests






Specifically, it's about one part He-3 per 100 million -- which gives you a better idea of the serious problems with mining the Moon for He-3 even if we finally do figure out how to fuse the stuff commercially (which we are absolutely nowhere near right now).
Go to the top of the page
 
+Quote Post
Bob Shaw
post Jun 4 2005, 05:26 PM
Post #26


Senior Member
****

Group: Members
Posts: 2488
Joined: 17-April 05
From: Glasgow, Scotland, UK
Member No.: 239



Mining the moon for He3 would, of course, give us access to all sorts of other things in the process - not least being meteorites from Earth, Mars, Venus and so on. Possibly even fossils from a certain nearby life-bearing planet (our own!).


--------------------
Remember: Time Flies like the wind - but Fruit Flies like bananas!
Go to the top of the page
 
+Quote Post
Toma B
post Jun 15 2005, 04:41 PM
Post #27


Member
***

Group: Members
Posts: 619
Joined: 9-May 05
From: Subotica
Member No.: 384



So there will not be another image of Earth for how long? huh.gif
Why don't they snap a picture at least once a week? blink.gif


--------------------
The scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.
Jules H. Poincare

My "Astrophotos" gallery on flickr...
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Jun 16 2005, 02:56 AM
Post #28





Guests






Because Messenger is usually too close to Earth to see it as more than a speck -- only during its close flybys of Earth will its camera be able to see Earth clearly. (I believe there is only one more Earth flyby planned before it moves on to using repeated flybys first of Venus and then of Mercury itself to finally put itself into an orbit almost parallel to Mercury, thus allowing it to use an acceptably small amount of fuel to finally brake into orbit around Mercury itself. The Europa Orbiter -- when they finally fly it -- will, after it enters orbit around Jupiter, use repeated flybys of Callisto, Ganymede, and finally Europa itself to match orbits in a similar way with Europa before braking into orbit around Europa.)
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Jun 16 2005, 02:57 AM
Post #29





Guests






"Because Messenger is usually too close to Earth to see it as more than a speck..."

Gaaah. I'm going senile. Make that "too FAR FROM Earth to see it as more than a speck".
Go to the top of the page
 
+Quote Post
gpurcell
post Jun 16 2005, 03:34 PM
Post #30


Member
***

Group: Members
Posts: 215
Joined: 21-December 04
Member No.: 127



QUOTE (BruceMoomaw @ Jun 16 2005, 02:56 AM)
Because Messenger is usually too close to Earth to see it as more than a speck -- only during its close flybys of Earth will its camera be able to see Earth clearly.  (I believe there is only one more Earth flyby planned before it moves on to using repeated flybys first of Venus and then of Mercury itself to finally put itself into an orbit almost parallel to Mercury, thus allowing it to use an acceptably small amount of fuel to finally brake into orbit around Mercury itself.  The Europa Orbiter -- when they finally fly it -- will, after it enters orbit around Jupiter, use repeated flybys of Callisto, Ganymede, and finally Europa itself to match orbits in a similar way with Europa before braking into orbit around Europa.)
*


Bruce, do you know if they are planning to do science during the Venus encounters?
Go to the top of the page
 
+Quote Post

31 Pages V  < 1 2 3 4 > » 
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 21st October 2014 - 05:26 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.