Professor Kasper in NASA article on a new view of solar wind

Associate Professor Justin Kasper (MIRA Executive Committee member) is quoted in a NASA article about his role in NOAA’s Deep Space Climate Observatory (DSCOVR).

In February, NOAA will launch DSCOVR into orbit around a spot known as Lagrange 1, which lies outside Earth's magnetic environment. According to the article, this is the “perfect place to measure the constant stream of particles from the sun, known as the solar wind, as they pass by.”

There are three facets of the solar wind: The movement of the positive particles, the movement of the negatively-charged electrons, and the alignment of the magnetic fields present in the plasma and its electric fields.

DSCOVR carries an instrument for each of these measurements. The velocity and direction of the positively-charged particles are measured by something called a Faraday cup, built by the Massachusetts Institute of Technology and operated by the Harvard-Smithsonian Center for Astrophysics and the University of Michigan.

The Faraday cup on DSCOVR plays another important role. It is a precursor to a similar instrument -- led by Kasper -- for NASA's Solar Probe Plus, planned for a 2018 launch. Solar Probe Plus will study the solar wind much closer to the sun. It will fly almost ninety times closer to the sun than DSCOVR and plunge repeatedly into the sun’s atmosphere. There the solar wind is denser and its physical processes faster, so the Faraday cup will be built to measure at a rate of 100 times per second. Feedback from the instrument on DSCOVR should help with design of the one being built for Solar Probe Plus. Moreover, once both are in space, the similarity between the instruments will ensure the validity of comparisons between the measurements at the sun and near Earth.

“When we proposed the DSCOVR Faraday cup we saw it as a pathfinder for the Solar Probe Plus mission," said Kasper, who is also the instrument lead for the Faraday cup on Solar Probe Plus. "We are extremely excited to be able to see how such a fast instrument behaves, and what we discover will feed right into our plans for Solar Probe Plus."

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DSCOVR was recently featured in USA Today.