Sea ice is frozen seawater floating on the surface of the ocean. Some sea ice is semi-permanent, persisting from year to year, and some is seasonal, melting and refreezing from season to season. The sea ice cover reaches its minimum extent at the end of each summer and the remaining ice is called the perennial ice cover. The 2007 Arctic summer sea ice has reached the lowest extent of perennial ice cover on record – nearly 25% less than the previous low set in 2005. The area of the perennial ice has been steadily decreasing since the satellite record began in 1979, at a rate of about 10% per decade. But the 2007 minimum, reached on September 14, is far below the previous record made in 2005 and is about 38% lower than the climatological average. Such a dramatic loss has implications for ecology, climate and industry.”
It’s a big day for NASA news: first, they announced their intention to build a moonbase by 2024, the first permanent manned “colony” outside the Earth’s biosphere. Then they released photos, taken from Martian orbit by the Reconaissance Orbiter, showing 1976’s twin Viking landers and the Spirit Rover, still happily trundling around since landfall in 2004.
And now? The U.S. space agency has announced a news conference tomorrow morning to present new “science results” from the Mars Global Surveyor, whose long-extended mission ended abruptly this month after the apparent failure of a solar panel and the resulting loss of power.
Whatever is it, they’re touting it as a “Significant Find.” Now, what exactly can one find, that is significant, on a desert planet? My money is that the surveyor shot an indistinct image of a dusty ruin, pointing skyward, the last gasp of a preindustrial civilization. Either that or Jimmy Hoffa.
Update: Commenter Ryan spots that NASAwatch expects the announcement to be water flowing on the surface of Mars. In all seriousness, the best I’d hoped for was an arroyo or dried-up riverbed: actual existing water makes the prospect of contemporary life on Mars far more likely.
