Remember AMSR-E? The instrument, built by Jaxa, mounted on the NASA AQUA satellite provided us with the best Sea Ice Concentration data (as well as a multitude of other data, e.g. Sea Surface Temperature) from 2002 to 4 October 2011. At that time the instrument was switched off, due to the increased friction in the drive of its big rotating disk antenna.
Well, it seems the instrument is not quite dead yet and from December 4, 2011 has been collected data at a reduced rotational speed ( 2 instead of 40 rpm). Jaxa announced:
AMSR-E Slow Rotation Data has been released
The AMSR-E automatically halted its observations and rotation on October 4, 2011 (UTC) due to increased rotation friction. After then NASA and JAXA began to analyze the situation and had been seeking for the way to restart AMSR-E observation. And on December 4, 2012 (UTC,) the AMSR-E restarted its observations and rotation with slow rotation (2 rotations per minute). JAXA completed initial radiometric and geometric correction for slow rotation data, and now AMSR-E Slow Rotation Data is available to public users.
This data is useful for users who cross-calibrate AMSR-E with other radiometers and who try to research using new feature by slow rotation and so on. This data is not JAXA's standard product. AMSR2 Standard Product is available for general user.
Good news for the inter calibration of the AMSR-E and AMSR2 data.
http://sharaku.eorc.jaxa.jp/AMSR/products/amsre_slowdata.html