Crescent Earth

The Earth captured from the Rosetta spacecraft as it passed by Earth.
.
ESA. Taken on 11/12/2009. Click to enlarge.
As seen on the Planetary Society blog.

Incoming asteroid--errr, satellite

Astronomers at the Catalina Sky Survey near Tucson discovered an object on November 7th and when the orbit was calculated it was a Near Earth Object (or NEO) and would barely pass by Earth in only five days time. By barely, it was calculated at only a Earth's diameter away--a little under 8,000 miles.

Photometric measurements suggested the object was 20m in diameter, which is pretty big as things go--the Meteor Crater parent body was estimated at 30-50m.

But as Russian astronomer Denis Denisenko noted on the MPML, the object had a peculiar orbit: it passed quite close by Mars at nearly the same time as an ESA orbiter called Rosetta. See a view at Mars here. And, Rosetta happens to have the largest solar panels short of the ISS, two 14 meter long panels that make 64 square meters in total, matching the expected brightness of the object. Sure enough, Rosetta is due at Earth for a orbit changing interaction with Earth in five days so it can rendezvous with a comet in 2014. The people in charge of maintaining minor planet orbits decried the lack of coordination between the artificial satellite organizations and the minor planet community--as satellites are launched it's easy to watch them go away, but the NEO watchers are rightfully concerned about inbound objects, and the data about spacecraft outside of near-Earth space is skimpy.

The view at Mars from Rosetta

The ESA's Rosetta spacecraft flew by Mars yesterday on its long mission to reach Comet 67P/Churyumov-Gerasimenko in 2014. As is standard, the spacecraft imaged Mars. What's ultimately so satisfying about this picture is perspective; the wholeness of the experience creating by putting a little of the spacecraft in the image. Look at the rest of the Rosetta images; none of them give you a sense of location as the special image taken by the piggyback Philae lander.

We are also only a day away from a Jupiter fly-by from the New Horizons spacecraft, speeding its way to Pluto as fast as it can, hopefully before the Pluto's atmosphere refreezes onto the surface. See where New Horizons is now.

Source: ESA