MESSENGER Enters Orbit Around Mercury

krswan writes "From the NASA press release: 'At 9:10 p.m. EDT, engineers in the MESSENGER Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., received the anticipated radiometric signals confirming nominal burn shutdown and successful insertion of the MESSENGER probe into orbit around the planet Mercury.' If you don't know much about this little spacecraft, check out its website. Designed with a completely passive cooling system, it will stay at 600C on the sun side, but room temperature behind the sunshade. During its 6-year journey it used solar panels as sails, relying on the solar wind instead of thrusters to adjust its trajectory. Over the next year it will build a high-res map of Mercury, and maybe determine if there is really ice hiding within polar craters (PDF)."

Comments

This is what space exploration should look like

[lwsimon]

This is what we should be doing - high-tech, compact probes doing important work all over the solar system.

Guys in suits in space is cool, but we need to learn, understand, and develop commercial applications first. The rest will come in time.

Re:This is what space exploration should look like

[camperdave]

Which program do you think has inspired more children to enter the sciences Apollo or Voyager? Which do you think has had a bigger cultural and economic impact, manned spaceflight or planetary probes?

Untrue

[MyLongNickName]

". During its 6-year journey it used solar panels as sails, relying on the solar wind instead of thrusters to adjust its trajectory"

I do not think this is true;

"These views of MESSENGER show the orientation at the start of trajectory correction maneuver 43 (TCM-43). Because TCM-43 will use the large bi-propellant thruster to place the spacecraft into orbit about Mercury, TCM-43 is also called Mercury orbit insertion (MOI). "

"MESSENGER’s dual-mode propulsion system includes a 660-newton (150-pound) bipropellant thruster for large maneuvers and 16 hydrazine-propellant thrusters for smaller trajectory adjustments and attitude control. The Large Velocity Adjust (LVA) thruster requires a combination of hydrazine fuel and an oxidizer, nitrogen tetroxide. Fuel and oxidizer are stored in custom-designed, lightweight titanium tanks integrated into the spacecraft’s composite frame. Helium pressurizes the system and pushes the fuel and oxidizer through to the engines."

And I know I read about this mission using chemical propulsion several times during the mission to make course adjustment.

Re:Untrue

[Buggz]

Not for boost, but for steering aka adjusting trajectory - sure! Like when you're rowing, just dipping an oar into the water will cause your boat to turn.

Re:Untrue

[Digicrat]

Inaccurately worded, but true none-the-less.

The solar wind isn't used in place of traditional thrusters, but as a complement to them, allowing the spacecraft to save precious fuel.

Google yields a good explanation of this from an old article at http://www.spacedaily.com/reports/MESSENGER_Sails_On_Sun_Fire_For_Second_Flyby_Of_Mercury_999.html discussing the cancellation of several TCMs due to the successful usage of solar sailing.

Re:Most boring planet?

[CFBMoo1]

Mercury has a magnetic field unlike Venus or Mars. If I remember one article right it's also more dense of a planet. Maybe we'll find some nifty raw materials there that some day in the future we could harvest.

Really proud of the U.S.A.

[wisebabo]

I know the US has done a lot of bad things and made some pretty bad mistakes but I just wanted to celebrate one of its (many) good achievements. Only the US has sent (or is sending) a probe to every major object in the solar system (yes that includes you Pluto). Only the US has launched four "Great Observatories" (Hubble, Chandra, Compton, Spitzer). Only the US has... well the list goes on and on even in just the field of unmanned space exploration.

Of course the Cosmos is not solely an American prerogative. So here's a question; why haven't other wealthy federations/countries (EU, Japan) been hitting in their weight class? Is it because only the US (and to a lesser extent) the USSR had the close linkage between the military development of ballistic missile technology and space exploration as a means of bolstering national pride? Or, is it because the US is a nation full of dreamers and visionaries who pursue ideals (and ideologies) that may not appeal as much to the pragmatic and efficient Europeans (I'm mostly thinking of Germany) and Japanese? Is the reason why 70% Americans profess to strongly believe in God the same reason why they are (relatively) so willing to spend billions on space exploration? Do the same impulses that drive many (stupid) Americans to deny Evolution and Global Warming paradoxically cause them to fund the most productive scientific community on earth?

And maybe that will answer this follow up question: will rising China follow (and perhaps surpass) the US in space exploration? If it is a matter of military development and national pride then perhaps yes. If it is something more cultural though...?

On a related note: there was a recent article in (I think) the NYTimes about how, the Chinese Central Committe (the assemblage that runs China) got together recently. Since many of the members of this elite group were laden with the latest iPad and iPhones, a major topic of discussion was; why hadn't China produced anyone like Steve Jobs and would it ever? Say what you will about Mr. jobs, he has created and revolutionized several industries from scratch (personal computing, "windows" based computing, computer animated movies (Pixar), digital distribution of media, portable digital media devices, cellphones, tablet computers). Basically the article concluded that unless China were to become more democratic, less authoritarian and less hierarchal, they would have little chance of allowing a (paraphrased) Beatles fanatic, fruitarian, hippy dropout who spent a year in India before returning to start a self-proclaimed revolution, from becoming a success.

Or is there another reason why the US has been blessed (cursed*?) by people like Jobs? (Education? Drugs? Fluorine in the water supply?)

*"cursed" might be what some of his employees would say. He, like others whom I would call visionary (like James Cameron), have not been known to provide the most caring and supportive of work environments.