Wednesday, February 10, 2010

Snowpocalypse -- and missed chances to glimpse the sun

Record snow in the DC area ("By the end of the snowfall Wednesday, areas of Washington will have seen as much as 52 inches in February 2010"). An earthquake in Chicago. The last ever night-time launch of the space shuttle (neat amateur video here).

Apparently the Mayans were cockeyed optimists, thinking we'd  last till 2012.

On the bright side (pun intended -- with all the shoveling in my future, I have to take joy where I can), NASA will soon be launching the Solar Dynamics Observatory.

I don't understand the orbit choice. SOHO, the last (IIRC) big solar observatory, was placed at the Earth/sun L1 point, with an unobstructed view of the sun. And SDO? From an article in the Register:

"SDO will operate in an inclined geosynchronous orbit at the "outer edges of Earth's radiation belt", around 36,000 km out. The orbit allows "nearly continuous, high data-rate contact" with the ground station, but will involve two annual "Earth shadow" eclipses, of 2-3 weeks each, and "three lunar shadow events each year", the agency notes."
The SDO orbit wasn't selected for ease of servicing. While the Hubble Space Telescope has been repaired and upgraded by space-shuttle crews on several occasions, the SDO can't be. Even if the shuttle fleet weren't about to be retired, shuttles lack the capacity to reach GEO. And the Obama administration has announced its plan to end the Constellation program that was to replace the shuttle.

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