Sunset

Proffesor Frédéric Pont at the University of Exeter has simulated what sunsets on planets orbiting distant stars  would look like.

What does the sunset look like on HD 189733 b? Amazingly, we know quite accurately. This is because the colour of the sunset is exactly what is measured when collecting the transmission spectrum of the atmosphere of a transiting planet. We have measured the transmission spectrum of ’189 with the STIS spectrograph on the Hubble Space Telescope. STIS covers visible wavelengths, and HD 189733 is bright enough that the precision of the spectrum is sufficient for a precise translation into colours perceived by the human eye.

What does the sunset look like on HD 209458 b?

Spirit, Already Dead

On January 26th, 2274 Mars days into the mission, NASA declared Spirit a 'stationary research station', expected to stay operational for several more months until the dust buildup on its solar panels forces a final shutdown.

If the Spirit rover is just a little robot crawling around on a little red planet somewhere, then why are we so sad that it is dying? The rover is certainly easy to anthropomorphize, but I think there is more to it. The spectrum of sentient to insentient, is just that a spectrum. When we speak of these concepts we make subtle judgments through the connotation of our words. For example is the robot going to die, or is it going to shutdown? On some level it must be alive, or, at least it was.

Landing on Titan

This strange movie is a visual aggregation of the data which the Huygens lander gathered when landing on Saturn's moon Titan on January 14th 2005. Huygens is part of the wildly succsesful Cassini-Huygens mission. Cassini is still taking fantastic pictures of Saturn and its moons while Huygens ended its journey on a methane riverbed and claims honors as the most distant touch-down ever made by a human built spacecraft. To the right here you can see the orange image that Huygens had as it came to rest stranded on the cold world; the rocks in the image are actually water ice. And further to the right is the grey image of a similary scaled image for comparison to the Moon's surface. I was struck by the flashing lights and strange sounds in the video. Every detail of the video expresses some aspect of the spacecrafts data aquisition. For a complete description of the data try this and here is an explanation for the sounds.

Sounds from a left speaker trace Huygens' motion, with tones changing with rotational speed and the tilt of the parachute. There are also clicks that clock the rotational counter, as well as sounds for the probe's heat shield hitting Titan's atmosphere, parachute deployments, heat shield release, jettison of the DISR cover and touch-down.

 Sounds from a right speaker go with DISR activity. There's a continuous tone that represents the strength of Huygens' signal to Cassini. Then there are 13 different chimes - one for each of DISR's 13 different science parts - that keep time with flashing-white-dot exposure counters.

Drake

Image by Lou Brooks

I just attended a colloquium by Frank Drake. Frank Drake is best known for his Drake equation which determines the number of intelligent civilizations in our galaxy that we might expect to encounter or rather have the possibility of communicating with. Drake told us that at the time the equation was something he thought up just before a conference in front of an eclectic collection of scientists and it was overshadowed by talking dolphins and Melvin Calvin (that is of the Calvin Cycle) winning the Nobel prize. The Drake equation went on to have quite a legacy, and despite the non-detection of intelligent extraterrestrial life people believe in the Drake equation's predictions today even more than they did then. I am not going to show or even discuss the Drake equation in depth here because if you know it you know it and it is not actually particularly enlightening, further to me the Drake equation is just a version of a Fermi problem that suffers from the Fermi paradox.

The Search for Extraterrestrial Intelligence, SETI, is an ongoing and very serious endeavor, for example the Allen Telescope Array is currently being constructed and looks very promising. As I always encourage people to get involved with programs like SETI@home; you could help discover aliens and what not simply by running a nifty screen saver (which I should mention is extremely scientifinic in fact, I quote "The colors you see in the graph signify absolutely nothing.", so you know it is real science). I leave you with words from an articulate speaker, Jill Tarter (a TED 2009 prize winner), to summarize.