Cartesian projection of the entire solar atmosphere as observed by the NRL SECCHI twin Extreme Ultraviolet Imagers at a temperature of 1.6 million degrees. SECCHI acquires full maps of the Sun every 10-20 min.
Cartesian projection of the entire solar atmosphere as observed by the NRL SECCHI twin Extreme Ultraviolet Imagers at a temperature of 1.6 million degrees. SECCHI acquires full maps of the Sun every 10-20 min.

Objectives
Advance the understanding of the 3-D structure of the Sun’s corona, the origin of Coronal Mass Ejections (CMEs), CME propagation through the heliosphere, and the dynamic coupling between CMEs and Earth.
CMEs, the most energetic phenomena in the solar system, are major drivers of geomagnetic space weather storms that adversely affect ISR, precision engagement, missile detection and intercept, Comms on the Move, spacecraft anomaly assessment, orbital tracking, polar flight activities, and the power grid. CMEs were discovered by NRL, with an NRL-built solar coronagraph, in 1971.

Approach
SECCHI: the solar and heliospheric imaging instrument suite on the NASA STEREO Mission

  • NRL is SECCHI PI institution for NASA; consortium of US and international partners
  • NRL led development of the 10 telescopes SECCHI suite
  • Builds on successful NRL LASCO coronagraph on NASA/SOHO, led to NASA award to NRL for NRL as PI institution for WISPR (NASA Solar Probe Plus coronagraph)

STEREO Mission: October 2006 Launch - present

  • Two identical satellites (STEREO A/Ahead-of-the-Earth & STEREO B/Behind-the-Earth) in ecliptic plane solar orbit
  • Earth-centered stereographic angle between STEREO satellites increases 45 degrees/year

Deliverable/Value/Accomplishment

  • NRL delivered the two SECCHI instrument suites to NASA; this included NRL in-house conception and optical design of the SECCHI COR2 coronagraph and the SECCHI Heliospheric Imager, leading the Goddard Space Flight Center in completion of the SECCHI COR1 coronagraph, and leading Lockheed-Martin (partner/sub to NRL) in completion of the SECCHI Extreme Ultraviolet Imager (EUVI)
  • NRL currently delivering to NASA the SECCHI Mission operations and data analysis from on site at NRL-DC
  • SECCHI results demonstrate improved accuracy (from 30 hours down to 8 hours) predicting CME impacts at Earth

SECCHI Heliospheric Imager
Conceived, developed, and operated at NRL, SECCHI’s Heliospheric Imager (HI) instrument on NASA’s STEREO spacecraft is a new remote sensing tool that tracks, for the first time, Coronal Mass Ejections (CMEs) as they pass through the volume of space between the Sun and the Earth. Images from HI show continuous solar wind outflow from the Sun and are applied to detect significant changes in solar outflow (often resulting from CMEs that are headed to Earth and arrive within 24 to 72 hours). Data from HI is useful towards validating HPC models of heliospace dynamics.