The Wide-field Infrared Survey Explorer (WISE) has run out of hydrogen in its secondary tank. This is the big one that kept the telescope cold. Now the telescope has warmed up to 45 K, and telescope emission has saturated the 22 micron band. But the 12 micron band is still working for now since the small primary hydrogen tank is still keeping the detectors cold. And the 3.4 and 4.6 micron bands are working as well as ever. The IAU Minor Planet Center just published electronic circulars announcing the discovery of two Near Earth Asteroids by WISE, 2010 QD2 and 2010 QE2. Based on optical brightness, both are a kilometer or more in diameter. The WISE data will be used to make more accurate diameter estimates later.

The Wilkinson Microwave Anisotropy Probe (WMAP) has finished all of its observations, including 9 years of CMB data, ending with 10 days of calibration tests at larger angles between the spin axis and the Sun.

Every 10 years the US astronomy community ranks proposed projects for the next decade. The 2010 report was released today, 13 Aug 2010, at 08:00 PDT. The top recommendations were the Wide Field Infrared Survey Telescope (WFIRST), formerly known as the Joint Dark Energy Mission (JDEM), and the Large Synoptic Survey Telescope (LSST).

I was on the Beyond Einstein Program Assessment Committee (BEPAC), and in 2006 we were told NASA had funding to start one mission before the decadal survey report came out, and we selected JDEM to be that mission. Unfortunately NASA only had funding to start ZERO missions before the end of the decade, but it is nice to see that the BEPAC’s judgment is still considered correct.

But this morning when I was looking for news about the report I found an article which said that:
“In space, the community’s top choice is the $1.6 billion Wide-Field Infrared Survey Explorer”!!!
Wow, WISE with 5 times its actual budget! This is no doubt an error that will be fixed, so I will insert a screen grab below:

Science Insider story on the 2010 Decadal Survey

WISE is still being eclipsed by the Earth, an effect known as night for those of us living on Earth, but on 11 July 2010 WISE also got eclipsed by the Moon. The graph below shows the output of a coarse Sun sensor (basically a solar cell) falling rapidly as the sunlight powering WISE was cutoff by the Earth’s limb, then rising rapidly 21 minutes later as the eclipse by the Earth ended. But the level stayed at about 30 percent of full sunlight for another 7 minutes due to the penumbra of the Moon. Of course the WISE telescope was looking 90 degrees away from the Sun and took no notice of the eclipse. I’m sure people on Easter Island had a more exciting view.

WISE Sun sensor output versus seconds since 1 Jan 2000.

WISE downloaded its one millionth 4-color frameset last night. It was taken 29-May-2010 20:23:14 UTC and centered at (l,b) = (90.33,14.53). The survey continues…

Saturday morning I volunteered at the JPL Open House, which was May 15-16 this year. Finally the WISE booth had real WISE data. Tens of thousands of visitors came to learn about space projects ranging from Earth observing satellites to the Planck mission studying the most distant parts of the observable Universe. Of course people were having fun too, including Tiffany and John Plunkett who were taking pictures of pigs in space. Here’s their picture of their pig flying past the Andromeda nebula, as seen by WISE:

Flying Pig

The Sun has now moved far enough North that WISE is being eclipsed when it passes over the South Pole. The orbit of WISE is inclined by 97.5 degrees, and the end of the orbit normal that is close to the Sun in the sky is at -7.5 degree declination. The Sun has now reached 15 degrees declination, so when WISE is over the South pole the elevation of the Sun is -22.5 degrees. But the horizon is depressed by 22.6 degrees at the elevation of WISE, so the Sun is now partially eclipsed over the poles. Within a day or two WISE will be experiencing total eclipses once per orbit.

WISE has passed 50 percent coverage of the sky on day 100 of 2010.

WISE has now observed the Galactic Center and is scanning into small positive longitudes. All of the frames near the Galactic Center have such a high density of objects that the automated astrometry pipeline failed, but the raw images show good image quality with at most a few percent of the pixels saturated. With last night’s deliveries WISE crossed over 500,000 framesets and has covered 40% of the sky.

WISE continues to find comets and asteroids through its NEOWISE program led by Amy Mainzer. The latest and quite interesting comet found by WISE is Comet C/2010 D4 (WISE) which has a perihelion distance of 7.2 AU! My list of WISE solar system discoveries shows that comets D1, D2 and D3 were all discovered by WISE as well.