by Paul Gilster | Jan 14, 2005 | Outer Solar System
The first images coming back from Titan are raw (i.e., unprocessed), and we’ll have more (up to 350, apparently) available soon. The first picture shows what appear to be drainage channels, as you can see below.
This is one of the first raw, or unprocessed, images from the European Space Agency’s Huygens probe as it descended to Saturn’s moon Titan. It was taken with the Descent Imager/Spectral Radiometer, one of two NASA instruments on the probe. Credit: ESA/NASA/University of Arizona
The second image (via Emily Lakdawalla in Darmstadt) seems to be from the surface. Notice the rounded rocks, perhaps evidence of erosion from some kind of liquid (though I notice JPL is calling these ice blocks rather than ‘rocks’). Now comes the fun part: we’ll be getting details and more images all night long and unravelling the data will take months. What a story, and what a triumph for ESA, NASA and the Italian Space Agency!
by Paul Gilster | Jan 14, 2005 | Outer Solar System
Incoming data shows that Huygens’ instruments were functioning nominally throughout the descent. From this morning’s (EST) press conference, this statement by Jean-Jacques Dordain, ESA’s Director General:
“The morning was good; the afternoon is better. We were an engineering success this morning, but we can say this afternoon that we are also a scientific success. We are the first visitors to Titan, and scientific data that we are collecting now shall unveil the secrets of the new world. In fact we have got on the ground station data from Huygens long after the touchdown, more than two hours. I must say that we are short of ground stations! The batteries are much more solid than the number of ground stations which can receive the signal. Cassini has just started to deliver the data collected by Huygens, and we might be able to see the results during the night.”
And this fascinating detail from Emily Lakdawalla’s weblog for the Planetary Society:
One thing that may have helped the probe last a long time was that it appeared to stay unexpectedly warm. At an elevation of only 50 kilometers (about 30 miles) above the surface, her interior was still at a balmy 25 C (77 F), despite the outside temperature being a frigid -180 C (-290 F). [Project scientist Jean-Pierre] Lebreton wasn’t ready to say what this might mean. It could be overperformance of the spacecraft, but it could also mean a wide variety of unexpected things about the atmosphere. For those of you who like instant results, I think you’ll be disappointed on an answer to this question, because after all Huygens was a mission focused almost entirely on Titan’s atmosphere, so it’s going to take a very long time to synthesize scientific conclusions from all of this.
by Paul Gilster | Jan 14, 2005 | Outer Solar System
Huygens, now on the surface of Titan, has been transmitting data for five hours now, twice the expected time. Signals received by the Parkes Observatory in Australia first confirmed that the probe had survived the landing. It has also been confirmed that at least one experiment — the Doppler Wind Experiment — has been successful.
Update: Cassini has turned toward Earth and is now transmitting Huygens data, with about forty minutes of preliminaries before the crucial science data are sent. ESA scientists should start looking at the first datasets around 1130 EST.
The key question remains: how sound are the data? From John Noble Wilford’s story on the New York Times Web site (free registration required):
The possibility remains that a design flaw in Cassini’s radio receiver system will hopelessly scramble the data. Engineers anticipated that signals from the wind-tossed Huygens would vary widely in frequency and strength, and thus compensated for it in the receiver’s design. But they had failed to take into account frequency shifts that would also throw off the timing of the encoded data, leaving it a garbled mess.
In early 2000, an ESA engineer recognized the problem. Finally, ESA and NASA engineers found a way to reduce the frequency shifts to acceptable levels by altering the trajectory and orientation of Cassini during the critical maneuvers.
by Paul Gilster | Jan 14, 2005 | Outer Solar System
The Green Bank radio telescope in West Virginia has picked up the Huygens carrier signal, which should have been activated after the opening of the main chute and the dropping of the heat shield. The signal carries no data other than this: Huygens made it through the entry into Titan’s atmosphere. We should have data available by 1310 EST, routed from Huygens through Cassini. From an ESA press release:
What the Green Bank radio telescope has detected is only a ‘carrier’ signal. It indicates that the back cover of Huygens must have been ejected, the main parachute must have been deployed and that the probe has begun to transmit, in other words, the probe is ‘alive’. This, however, still does not mean that any data have been acquired, nor that they have been received by Cassini. The carrier signal is sent continuously throughout the descent and as such does not contain any scientific data. It is similar to the tone signal heard in a telephone handset once the latter is picked up.
Says Project Scientist Jean-Perre Lebreton, “It looks like we heard the baby crying.”
Update: ESA now reporting data as well as the carrier signal.
by Paul Gilster | Jan 13, 2005 | Outer Solar System
The Planetary Society’s Emily Lakdawalla is covering Huygens events from Darmstadt here. From her latest post:
Another item that was news to me came from Marty Tomasko, the University of Arizona researcher who heads the Descent Imager Spectral Radiometer team (that’s the main camera on Huygens). His last images are expected to come from about 150 meters off the ground. But, if Huygens survives the landing, DISR could still take pictures. What’s cool about that is if Huygens lands in a liquid, it would be taking pictures through that liquid, seeing what’s suspended in it. But I’ve been taking an informal poll of the science team to find out what they think they will land on, and no one has predicted liquid. The predictions range from “icy” to “squelchy” (the latter is how Surface Science Package investigator John Zarnecki described it ). After a few of these questions during the press briefing, Tomasko finally said, “This is probably not the best day to speculate. Probably you should save that question for 36 hours, and then we’ll have a much better answer to give you.”
