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This early morning at JPL ... Steve Collin's celebrates as the first close up's of Comet Hartley2 come up on the screen of the control room.

First close-ups ... higher rez photos were still being downloaded when I had to leave

Steve linked this one on his facebook page. Pretty cool.

http://twitpic.com/33unfp/full" onclick="window.open(this.href);return false;

And Nasa is beginning to add to its gallery online....

http://www.nasa.gov/mission_pages/epoxi ... index.html" onclick="window.open(this.href);return false;

Very interesting. I'd like to know where it is in space (i.e., near which planet, orbit, etc.). And is EPOXI a 2-part mission? (Adhesive humor. ) Here's text from NASA's site:

PASADENA, CALIF. – NASA's EPOXI mission successfully flew by comet Hartley 2 at about 7 a.m. PDT (10 a.m. EDT) today, and the spacecraft has begun returning images. Hartley 2 is the fifth comet nucleus visited by a spacecraft.

Scientists and mission controllers are currently viewing never-before-seen images of Hartley 2 appearing on their computer terminal screens.

"The mission team and scientists have worked hard for this day," said Tim Larson, EPOXI project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "It's good to see Hartley 2 up close."

Mission navigators are working to determine the spacecraft's closest approach distance. Preliminary estimates place the spacecraft close to the planned-for 700 kilometers (435 miles). Eight minutes after closest approach, at 6:59:47 a.m. PDT ( 9:59:47 a.m. EDT), the spacecraft's high-gain antenna was pointed at Earth and began downlinking vital spacecraft health and other engineering data stored aboard the spacecraft's onboard computer during the encounter. About 20 minutes later, the first images of the encounter made the 37-million-kilometer (23-million-mile) trip from the spacecraft to NASA's Deep Space Network antennas in Goldstone, Calif., appearing moments later on the mission's computer screens.

"We are all holding our breath to see what discoveries await us in the observations near closest approach," said EPOXI principal investigator Michael A'Hearn of the University of Maryland, College Park.

A post-encounter news conference will be held at 1 p.m. PDT (4 p.m. EDT) in the von Karman auditorium at JPL. It will be carried live on NASA TV. Downlink and schedule information is online at http://www.nasa.gov/ntv" onclick="window.open(this.href);return false; . The event will also be carried live on http://www.ustream.tv/nasajpl2" onclick="window.open(this.href);return false; .

EPOXI is an extended mission that utilizes the already "in-flight" Deep Impact spacecraft to explore distinct celestial targets of opportunity. The name EPOXI itself is a combination of the names for the two extended mission components: the extrasolar planet observations, called Extrasolar Planet Observations and Characterization (EPOCh), and the flyby of comet Hartley 2, called the Deep Impact Extended Investigation (DIXI). The spacecraft has retained the name "Deep Impact."

JPL manages the EPOXI mission for NASA's Science Mission Directorate, Washington. The University of Maryland is home to the mission's principal investigator, Michael A'Hearn. Drake Deming of NASA's Goddard Space Flight Center, Greenbelt, Md., is the science lead for the mission's extrasolar planet observations. The spacecraft was built for NASA by Ball Aerospace & Technologies Corp., Boulder, Colo.

Not knowing anything about this stuff, what exactly are we seeing? Is this a "photograph" or some other form of image capture? To most, a comet is something with a long tail. Does this have that and it's just not captured in this type of image? What are the "jets" coming out of the nucleus? What is the light source?

Dirty Snowball is also an obscene sex act.

That's one Google search I'd like to take back. :unimpressed:

Rick -- I believe that is a straight digital photograph using visible light.

Comets in general are made up of ice and bits of rock or dust. They spend most of their time far out beyond the orbit of Pluto. The ones we get to see have elongated elliptical orbits that carry them into the domain of the planets where they are lit up by the sun. The tails are formed when they get close enough to the sun for the sun's light to evaporate some of the ice, releasing dust, ice fragments, and water vapor. The loose debris and vapor is "blown" away from the sun by the momentum of the sunlight ("whoa, light has momentum?" That Einstein guy and his wacky ideas...), so it forms a tail pointing away from the sun. The tail is really bright because light scatters off the small particles in all directions. The glow and streaks you see in the photos are probably jets of water vapor boiling off the surface closest to the sun. If the comet gets closer to the sun those will develop into the tail.

Greg Peng wrote:That's one Google search I'd like to take back. :unimpressed:

You fool!

Doug Kott wrote:And is EPOXI a 2-part mission? (Adhesive humor. )

Actually.... "EPOXI combines two targets: the Deep Impact Extended Investigation (DIXI), and the Extrasolar Planet Observation and Characterization (EPOCh). "

Will Kalman wrote:

Doug Kott wrote:And is EPOXI a 2-part mission? (Adhesive humor. )

Actually.... "EPOXI combines two targets: the Deep Impact Extended Investigation (DIXI), and the Extrasolar Planet Observation and Characterization (EPOCh). "

I often miss my target with EPOXI, but it cleans up well with denatured alcohol.

That Collins guy needs a haircut and a good shave!





Nice job, Steve!!!!!

John Stimson wrote:Rick -- I believe that is a straight digital photograph using visible light.

Comets in general are made up of ice and bits of rock or dust. They spend most of their time far out beyond the orbit of Pluto. The ones we get to see have elongated elliptical orbits that carry them into the domain of the planets where they are lit up by the sun. The tails are formed when they get close enough to the sun for the sun's light to evaporate some of the ice, releasing dust, ice fragments, and water vapor. The loose debris and vapor is "blown" away from the sun by the momentum of the sunlight ("whoa, light has momentum?" That Einstein guy and his wacky ideas...), so it forms a tail pointing away from the sun. The tail is really bright because light scatters off the small particles in all directions. The glow and streaks you see in the photos are probably jets of water vapor boiling off the surface closest to the sun. If the comet gets closer to the sun those will develop into the tail.

Thanks John.

Greg Peng wrote:That's one Google search I'd like to take back. :unimpressed:

LMAO

Geez, I had no idea! :barf:

It was really neat getting to see these first close-ups at the same time as the team that's been working
for two years on the project, while dining on coffee and pastries, and having various particpants explaining what was going on.

We also got to see a scientist make a pint size comet using water, dirt, ice cream, dried ice, more water ... while sneaking bites of ice cream.

I would definitely go to the JPL Open House when you have a chance. The 3D close-up video of the suns surface is not to be missed!

Gotta go to that open house...

Back in 1993, our magazine did a test on JPL's micro-rover called Rocky IV at the time; I think it became Sojourner as part of the Pathfinder mission (I bet Steve could clarify this!). Written by a very talented guy named Kim Reynolds who moved to the Dark Side (Motor Trend!) a while back. Top speed was 0.037 mph, with a quarter-mile time of 24,139 seconds. But entry velocity into the Martian atmosphere was 14,000 mph!

Doug Kott wrote:Top speed was 0.037 mph, with a quarter-mile time of 24,139 seconds. But entry velocity into the Martian atmosphere was 14,000 mph!

slow and steady wins the race

Doug Kott wrote:Gotta go to that open house...

Back in 1993, our magazine did a test on JPL's micro-rover called Rocky IV at the time; I think it became Sojourner as part of the Pathfinder mission (I bet Steve could clarify this!). Written by a very talented guy named Kim Reynolds who moved to the Dark Side (Motor Trend!) a while back. Top speed was 0.037 mph, with a quarter-mile time of 24,139 seconds. But entry velocity into the Martian atmosphere was 14,000 mph!

April issue?

Yes, our April Fools' road test. We've done a lot of eclectic things over the years...Goodyear blimp (and the new Zeppelin up at Moffet Field), Alaskan sled dog team, sedan chair carried by servants, Concorde vs. QE2, P-51 vs. Messerschmitt (the latter a micro-car, not the warbird).