Stories tagged JPL


The Curiosity rover: It's going to look for signs of Mars' past habitability. Also, it's way bigger than the other Mars rovers; about 2,000 pounds, and the size of a compact car.
The Curiosity rover: It's going to look for signs of Mars' past habitability. Also, it's way bigger than the other Mars rovers; about 2,000 pounds, and the size of a compact car.Courtesy NASA JPL
Wait, who was I quoting in that headline? Me. I was quoting me, from when I described the upcoming Mars rover landing in my head as "pretty frickin' awesome." Or ... that was very nearly what I thought, but the specifics of what goes on in my brain pit are for adult ears only.

Which adult? This one. Me.

Anyway, NASA's Jet Propulsion Laboratory has produced a video about how the landing of the Mars rover Curiosity will go down, when the spacecraft carrying it reaches the Martian atmosphere on August 4. As you'll see when you watch the video below, there's dramatic music, scientists and engineers speaking dramatically, and dramatic flashing graphics. All very nice and of high production value, but it makes me want to say, "Hey, don't be dorks, dorks. Geez."

But I can't. Because it actually looks pretty awesome. The spacecraft is going to enter the atmosphere going 13,000 miles an hour, which will heat it up to about 1600 degrees. Then a giant, super tough parachute will shoot out, and slow it down to a couple hundred miles an hour. And then the capsule will break open (before it hits the ground), and another flying device will fall out, the "Sky Crane." The Sky Crane will use rockets to zoom away, and then hover above the surface of the planet. It will then lower the actual rover down on a cable. Once the rover touches down, the crane will blast off again, so it doesn't crash into the rover. Pretty amazing. Take a look:

August 4!


Trajectory of comet Elenin
Trajectory of comet EleninCourtesy NASA/JPL-Caltech
Below is a news release from NASA/JPL about a comet that is going through some difficult times. NASA is sort of harsh in this release, imho, and really does not take the comet's feelings into account. Take a gander to see what I mean. Even the title is a little severe.

NASA Says Comet Elenin Gone and Should Be Forgotten

Comet Elenin is no more.

Latest indications are this relatively small comet has broken into even smaller, even less significant, chunks of dust and ice. This trail of piffling particles will remain on the same path as the original comet, completing its unexceptional swing through the inner solar system this fall.

"Elenin did as new comets passing close by the sun do about two percent of the time: It broke apart," said Don Yeomans of NASA's Near-Earth Object Program Office in Pasadena, Calif. "Elenin's remnants will also act as other broken-up comets act. They will trail along in a debris cloud that will follow a well-understood path out of the inner solar system. After that, we won't see the scraps of comet Elenin around these parts for almost 12 millennia."

Twelve millennia may be a long time to Earthlings, but for those frozen inhabitants of the outer solar system who make this commute, a dozen millennia give or take is a walk in the celestial park. Comet Elenin came as close as 45 million miles (72 million kilometers) to the sun, but it arrived from the outer solar system's Oort Cloud, which is so far away its outer edge is about a third of the way to the nearest star other than our sun.

For those broken up over the breakup of what was formerly about 1.2 miles (two kilometers) of uninspiring dust and ice, remember what Yeomans said about comets coming close to the sun – they fall apart about two percent of the time.

"Comets are made up of ice, rock, dust and organic compounds and can be several miles in diameter, but they are fragile and loosely held together like dust balls," said Yeomans. "So it doesn't take much to get a comet to disintegrate, and with comets, once they break up, there is no hope of reconciliation."

Comet Elenin first came to light last December, when sunlight reflecting off the small comet was detected by Russian astronomer Leonid Elenin of Lyubertsy, Russia. Also known by its astronomical name, C/2010 X1, Elenin somehow quickly became something of a "cause célèbre" for a few Internet bloggers, who proclaimed this minor comet could/would/should be responsible for causing any number of disasters to befall our planet.

Internet posts began appearing, many with nebulous, hearsay observations and speculations about earthquakes and other disasters being due to Elenin’s gravitational effects upon Earth. NASA’s response to such wild speculations was then in turn speculated to be an attempt to hide the truth.

"I cannot begin to guess why this little comet became such a big Internet sensation," said Yeomans. "The scientific reality is this modest-sized icy dirtball's influence upon our planet is so incredibly miniscule that my subcompact automobile exerts a greater gravitational influence on Earth than the comet ever would. That includes the date it came closest to Earth (Oct. 16), when the comet’s remnants got no closer than about 22 million miles (35.4 million kilometers)."

Yeomans knows that while Elenin may be gone, there will always be Internet rumors that will attempt to conjure up some form of interplanetary bogeyman out of Elenin, or some equally obscure and scientifically uninteresting near-Earth object. Thinking of ways to make himself any more clear about the insignificance of this matter is somewhat challenging for a scientist who has dedicated his life to observing asteroids and comets and discovering their true nature and effects on our solar system.

"Perhaps a little homage to a classic Monty Python dead parrot sketch is in order," said Yeomans. "Comet Elenin has rung down the curtain and joined the choir invisible. This is an ex-comet."
NASA detects, tracks and characterizes asteroids and comets passing relatively close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes the physical nature of a subset of them, and predicts their paths to determine if any could be potentially hazardous to our planet. There are no known credible threats to date.

Its like the person writing this had a personal vendetta against this poor comet. Though the Monty Python reference at the end helps lighten the mood, the overall dismissive tone of this news release is a bit sad.

Poor Elenin and its remaining "piffling particles".


Comet Temple 1
Comet Temple 1Courtesy NASA/JPL-Caltech/UMD
The following is from a listserv I am on that I thought was interesting.

On February 14, NASA's Stardust-NExT (New Exploration of Tempel 1) mission will encounter Comet Tempel 1, providing a unique opportunity to measure the dust properties of two separate comets (Wild 2 and Tempel 1) with the same instrument for accurate data comparison. The encounter will also provide a comparison between two observations of a single comet, Tempel 1, taken before and after a single orbital pass around the sun.

NASA's Stardust spacecraft will fly within 200 kilometers (about 124 miles) of Comet Tempel 1 on February 14, 2011, at about 8:36 p.m. Pacific Standard Time.

NASA's Deep Impact mission observed Comet Tempel 1 in the summer of 2005, as the comet was inbound toward the Sun on its approximately 5.5-year orbit between Mars and Jupiter. Deep Impact's primary mission was to deliver a special impactor spacecraft into the path of Comet Tempel 1. The spacecraft -- and many ground-based observers -- observed the impact and the ejected material. Scientists were surprised the cloud was composed of a fine, powdery material, not the expected water, ice, and dirt. The spacecraft did find the first evidence of surface ice on the surface of a comet instead of just inside a comet.

The Stardust-NExT mission is a low-cost use of an in-flight spacecraft redirected to a new target. Prior to its tasking for Tempel 1, the Stardust spacecraft successfully flew through the cloud of dust that surrounds the nucleus of comet Wild 2 in Jan. 2004. The particles of cometary material and gathered during this flyby were then returned to Earth aboard a sample return capsule which landed in the Utah desert in January 2006.


The monthly JPL "What's Up" video podcast (above) features the January Quadrantids, which is a meteor shower that peaks in the morning hours of Tuesday January 4th. It's a good night with no moon, and while the shower will look best for our friends in Europe, if it's clear and you are awake, you should be able to spot it between and below the big and little dippers.

I thought it interesting that the meteor shower was named after a constellation that has been demoted. You're not alone Pluto - that International Astronomical Union is a cold-hearted bunch.

Generally interested in meteor showers? Here's a meteor shower calendar.