Science Seminars

2/26/2009 – Taking AIM at the space environment–When bad space weather is good

Speaker: Dan Baker, LASP
Date: Thursday, Feb 26, 2009
Time: 4:00pm
Location: LSTB 299

Seminar Abstract:

The AIM (Aeronomy of Ice in the Mesosphere) spacecraft was launched on 25 April 2007. AIM is currently producing all planned observations. Some days after launch, however, AIM began to exhibit a problem in which it would not always achieve proper receiver uplink communications lock. During several periods from May 2007 to present there have been days without any successful uplinks from the ground operators to AIM. In this context, we examined solar conditions and geomagnetic activity. We formed the tentative hypothesis that higher solar wind speeds would lead to greater geomagnetic activity and this, in turn, seemed to lead to improved AIM operations. In this paper we present analysis of AIM bitlock to show when relative improvements or diminutions in spacecraft operations have occurred. We conclude that the spacecraft bitlock problem clearly is related, in part, to space environment conditions (along with a gradual secular trend toward lower performance). The best predicator of ‘good lock’ state seems to be a shift from low (or quiet) geomagnetic and solar wind conditions toward more disturbed conditions. We do not fully understand the mechanism(s) by which disturbed space weather improves AIM performance. However, we note that use of space weather forecast tools has been an important, supportive adjunct to this key new space flight program.