Brian's Brain

Last week, I had quite a thrill. It wasn't cheap. But it was free...well, except for my taxpayer contribution to it.

On the way back home from my customary early morning first walk with the dog, I noticed my across-and-down-the-street neighbors standing in their driveway. The neighborhood is normally pretty dead at 6AM, so when they waved me over I decided to see what was up. They're satellite fans (for professional reasons, among others...note the location of the Americas editorial office...) and, as it turns out, they were waiting for the International Space Station (which isn't, I know, technically a satellite...and yes, I also know, isn't a NASA-only program) to pass overhead.

I'm not sure which of the multitude of online resources they used to determine this, although the docent at an astronomy seminar I attended last Saturday night recommended Heavens-Above. Regardless, right on schedule the ISS emerged on the southwest horizon a few minutes later, glittering brightly (estimated value –2, according to my neighbors) in the reflected light of the partially illuminated moon and pending dawn. We were able to discern it for nearly the entire duration of its six-minute (it was moving fast) sojourn across the sky...it disappeared from view shortly before dipping beneath the northeast skyline due to contending illumination from the soon-to-rise sun.

I was admittedly quite moved by the event. While I'd had conceptual knowledge of the ISS (which, by the way, was just forced to dodge space junk for the first time in five years) for quite some time now, I'd never seen it with my own eyes before. And although I see satellites almost every night, it's quite different to comprehend a spacecraft that at the time contained 5 human beings. Being born in 1966, I'm too young to remember the Mercury program, and having lived in light pollution-plagued Sacramento until last October, I'd never bothered trying to see the Space Shuttle.

In light of last week's experience, I thought that now would be as good a time as any to update you on other space programs whose news I've been collecting:

• The maneuvers NASA successfully orchestrated during Cassini's mid-August fly-by of Enceladus, one of Saturn's moons, are pretty mind-boggling (and identified the source of the moon's periodic ice plume emissions, to boot). Saturn's distance from Earth ranges from 1,195,772,020 km (aka ~66.5 minutes at the speed of light in a vacuum, 299,792.458 km/sec, i.e. the rate at which radio communications from Earth to Cassini travel) to 1,658,854,980 km (~92.25 minutes)...I'm not sure what the exact Earth-to-Saturn distance was during the Cassini fly-by of Enceladus. At the time, Cassini was going 40,000 mph (~64,374 km/h, aka ~18 km/sec). And in spite of those formidable barriers, NASA was able to put Cassini in a moon-matching spin that resulted in clear captured images. This Slashdot comment neatly sums up my thoughts: "2 wind-up orbits around the Sun, 2 gravitational slingshot maneuvers by Venus, one each by Earth and Jupiter, all with only 1 course correction. Then 7 years later it goes into orbit around Saturn! Oh, and it is powered with plutonium. It then sweeps by Enceladus 22 times, drops a probe on Titan, and does countless other science experiments and images. This is why they call it rocket science. Wow."
• Early results from the Fermi Gamma-Ray Space Telescope are very positive, and optimism is high that GLAST will detect the fingerprints of dark matter. As the Slashdot post notes, "The data gathered in just its first few hours of operation is reportedly comparable to the data from the Energetic Gamma-Ray Experiment Telescope, which gathered data for nine years back in the 1990's."
• Speaking of dark matter, PAMELA (the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics, a project in which NASA does not participate) has also collected some encouraging preliminary results on this particular topic.
• Back to NASA: the intrepid Mars explorers Opportunity and Spirit are still trekking, collecting and passing along their observations. Both are showing signs of age...Opportunity has a stuck robotic arm, while Spirit has a broken wheel. But keep in mind that the initial mission (and therefore the rovers' design) was forecasted to last only 90 days, through April of 2004. That's four years and over four (or almost five, in Spirit's case) months ago, folks.
• And speaking of extended missions, let's not forget the more recent Phoenix lander which, as Wired notes, also went into extra innings last week after having discovered definitive evidence of water on Mars back on June 19^th.
• Last but not least, check out this pictorial spread (more from Slashdot) on the preparations for the last planned service mission to the Hubble Space Telescope, by the Space Shuttle Atlantis in early October.