Solar Wind Observations from 10 to 30 AU Measured With The New Horizons Solar Wind Around Pluto (SWAP) Instrument
Tuesday, 16 December 2014: 11:35 AM
Beginning in 2012 the New Horizons mission to Pluto began collecting solar wind observations during the spacecraft hibernation greatly increasing the solar wind coverage. We have extensively analyzed both the laboratory and flight calibration measurements for the Solar Wind Around Pluto (SWAP) instrument to produce a data set of solar wind observations at times when the New Horizons spacecraft is spinning. This full data set spans from 10 to 30 AU, and the improved coverage portion spans from 20- 30 AU. Coincidently, in 2012 and 2013 the ACE, STEREO A, and STEREO B were well separated in longitude. We compare the New Horizons speeds with propagated 1 AU speed measurements, and find many of the largest scale structures persist beyond 20 AU. The New Horizons solar wind coverage between 20 and 30 AU is now extensive enough to examine the temperature-speed relationship and compare that to the relationship found in the inner heliosphere and to that in the Voyager 2 observations. Upon initial examination we also find a temperature-speed relationship that persists in the 20-30 AU distance range.