Closest non-impacting object in our asteroid catalog came by, changed direction by 60°

Asteroid 2011 CQ1 made a record close Earth approach on February 4th, 14 hours after its discovery. It passed to within 0.85 Earth radii (5480 km) of the Earth's surface: This 'flying sofa', only about one meter in diameter, is the closest non-impacting object in our asteroid catalog to date. Prior to the Earth close approach, this object was in a so-called Apollo-class orbit that was mostly outside the Earth's orbit. Following the close approach, the Earth's gravitational attraction modified the object's orbit to an Aten-class orbit where the asteroid spends almost all of its time inside the Earth's orbit. The close Earth approach changed the asteroid's flight path by about 60°. There are nearly a billion objects of this size and larger in near-Earth space and one would expect one to strike Earth's atmosphere every few weeks on average where they airburst; only rarely do even a few small fragments reach the ground.

In other small bodies news a paper describes the outcome of NEOWISE, the (full) mission of the WISE observatory. • Asteroid transits over planet disks are more frequent than one might think. • Rob McNaught's 58th comet has been discovered, also pics of a small comet near a galaxy and of Hartley 2 near M 50 (more). • A paper on human perception may be of relevance for visual meteor observers. • A nice fireball over Italy, also discussed here. • Debate over the first impact crater in China and the meaning of the Kamil structure for impact physics. • Regarding larger bodies, the storm on Saturn on Feb. 6 and Feb. 5 (plus a progress report, rather old Keck pics of the SEB revival on Jupiter and Jupiter & the Moon on Feb. 6.

In solar research we celebrate one year of the SDO in orbit. • Results on CME ripple structures and particle acceleration near Earth. • The two STEREO s/c are now seeing the entire Sun, als also hailed here, here, here, here, here, here, here, here, here, here, here and hier. • How LOFAR saw the solar eclipse on Jan. 4 in radio. • A new sequence for SN 2011B. • A bright outburst of star (with a crazy name) and an outburst of Z Cam. • New insights into Eps Aur. • Amateur imaging of a z=6 object. • Some images of NanoSail D (also here and here), plus the flare geometry. • And finally, returning to SDO's launch a year ago, a new kind of halo effect triggered by its rocket.