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View Full Version : So is the Mercury MESSENGER still a go for 2004?



Earl Snake-Hips Tucker
2003-Mar-05, 07:24 PM
http://messenger.jhuapl.edu/

ToSeek
2003-Mar-05, 08:20 PM
The propulsion system (http://messenger.jhuapl.edu/press_release_1_31_03.html) is complete as of January 31.

The March 2004 launch date is a hard deadline due to the planetary configurations necessary. MESSENGER either launches then or not for quite a long time (years) thereafter. I worked in APL's Space Department for a while, and MESSENGER was by far the most frantic project at the time.

Zap
2003-Mar-05, 10:01 PM
Good. It's about time we send another spacecraft to Mercury (BTW, there is another Mercury mission in the works called BepiColumbo, it will come shortly after MESSENGER). Some unanswered questions about Mercury include

-Origin of Mercury's high density
-Composition and structure of its crust
-Tectonic and volcanic history
-Characteristics of the thin atmosphere and miniature magnetosphere
-Nature of the mysterious polar caps

If all goes well, MESSENGER will begin extensive studies on Mercury in 2009.

ToSeek
2003-Mar-19, 04:52 PM
One year to go! (http://www.spaceflightnow.com/news/n0303/18messenger/)

sacrelicious
2003-Mar-26, 10:47 PM
strange name if you ask me. exactly what kind of message are we sending to mercury? maybe something like "hey, get off of there, it's hot!", or "dude, better duck or that solar flare will fry ya!"

yes, i think they could have thought of a much better name than "messenger" for a probe that is intended for as hostile and desolate a planet as that.

Senor Molinero
2003-Mar-26, 11:37 PM
Sacrelicious,
Mercury was the messenger of the Roman gods, (Greek equivalent Hermes) because he travelled so swiftly through the heavens.

sacrelicious
2003-Mar-27, 12:15 AM
Sacrelicious,
Mercury was the messenger of the Roman gods, (Greek equivalent Hermes) because he travelled so swiftly through the heavens.

well I know that, but it still doesn't fit with the objective of the mission. it's just a clumsy reference.

ToSeek
2003-Dec-22, 06:13 PM
MESSENGER spacecraft shipped from APL to Goddard for environmental testing (http://www.spaceflightnow.com/news/n0312/21messenger/)

This means the spacecraft has been successfully put together. This step is to make sure it can handle the rigors of launch and the space environment.

Sever
2003-Dec-30, 04:54 AM
Mercury has ice caps? :o :o :o

Swift
2003-Dec-30, 01:42 PM
Mercury has ice caps? :o :o :o
Obviously not in direct sunlight. It is suspected that in some very deep craters, where the bottom is in permanent shadow, there is probably ice. This would be particularly true at the poles (sun would be closer to the horizon). The night side of Mercury also get very cold.

cyswxman
2003-Dec-31, 03:43 PM
By the way, Earl...Welcome to the board!! :D

ToSeek
2004-Mar-10, 05:03 PM
MESSENGER ships to KSC (http://www.spaceref.com/news/viewpr.html?pid=13807) - preparing for May 11 launch.

ToSeek
2004-Apr-07, 04:17 PM
MESSENGER getting prepped for a July launch (http://www.floridatoday.com/news/space/stories/2004a/spacestoryN0407MERCURY.htm)

tracer
2004-Apr-07, 05:50 PM
The March 2004 launch date is a hard deadline due to the planetary configurations necessary. MESSENGER either launches then or not for quite a long time (years) thereafter.
?? A launch in July 2004 hardly sounds like "years" after March 2004.

ToSeek
2004-Apr-07, 06:25 PM
The March 2004 launch date is a hard deadline due to the planetary configurations necessary. MESSENGER either launches then or not for quite a long time (years) thereafter.
?? A launch in July 2004 hardly sounds like "years" after March 2004.

Yes, I was wondering that myself. I guess there was more wiggle room in the launch date than I was aware of. Apparently the window runs through August 13. (http://www.spacetoday.net/Summary/2272) So there is some wiggle room, but they've already used up most of it.

EDIT: more right than I thought. From Wikipedia (http://en.wikipedia.org/wiki/MESSENGER):


The spacecraft was scheduled to launch during a 12-day window that opens May 11, 2004, aboard a Boeing Delta II rocket from Cape Canaveral Air Force Station, Florida. But on March 26, 2004, NASA announced that a later launch window starting at July 30, 2004 with a length of 15 days would be used. This will significantly change the trajectory of the mission and delay the arrival by two years.

The new plan calls for MESSENGER to make an Earth flyby a year after launch to receive a gravity-assisted boost, two swings past Venus in October 2006 and June 2007, then three flybys of Mercury in January and October 2008 and September 2009 before starting a year-long orbit in March 2011.

Originally, the craft was to use a gravitational slingshot maneuver passing Venus three times to aid its insertion into Mercury orbit, reaching it in 2009.

So MESSENGER is going to leave a couple of months late but arrive a couple of years late.

tracer
2004-Apr-08, 01:28 AM
Yeah, it'll take two more years before it can orbit Mercury, but look on the bright side -- its first flyby of Mercury will happen a year earlier than the orignal Mercury rendezvous date!

Maybe those flybys will give us some good pictures of the "other" side of Mercury (the side that Mariner 10 couldn't photograph).

JohnOwens
2004-Apr-08, 05:27 AM
Yay! We can finally get rid of that blank half in Celestia in a few years! :wink:

Jack Higgins
2004-Apr-08, 12:12 PM
:D

ToSeek
2004-Apr-12, 04:10 PM
MESSENGER to the Sun (http://www.astrobio.net/news/modules.php?op=modload&name=News&file=article&sid= 916&mode=thread&order=0&thold=0) - more about MESSENGER and particularly how it will manage to avoid being toasted.

jfribrg
2004-Apr-14, 02:54 PM
Can someone explain why all these flybys are necessary? Did Sprit and Opportunity use any gravity assists? If not then how did they get to Mars so fast? Or are we simply trying to maximize the scientific value of the mission by sending Messenger to Venus instead of going straight to Mercury?

ToSeek
2004-Apr-14, 04:12 PM
Can someone explain why all these flybys are necessary? Did Sprit and Opportunity use any gravity assists? If not then how did they get to Mars so fast? Or are we simply trying to maximize the scientific value of the mission by sending Messenger to Venus instead of going straight to Mercury?

It's all about changing your velocity and where you are in the gravity well. Mars is easy to get to because it's close by, and the relative speeds between the Earth and Mars are not that great. Mercury is deep in the Sun's gravity well, so slowing a probe down enough to be captured into orbit is difficult. And MESSENGER is a low-cost Discovery mission, not a full-up effort like Galileo, Cassini, or New Horizons. And even Galileo and Cassini had to use inner-planet gravitational assist trajectories in order to get to Jupiter with their allotted quota of fuel.