Lengthy Coronal Hole Generating Aurora On Earth

Image Credit: Solar Dynamics Observatory, NASA

January 7, 2017 – The Solar Dynamics Observatory (SDO) captured images of an elongated coronal hole that rotated across the face of the sun from January 2-5, 2017. In this wavelength of extreme ultraviolet light it appears as a dark area near the center and lower portion of the sun.

Coronal holes are areas of open magnetic field from which solar wind particles can escape from the sun and stream into space at about 400-500 miles per second — or roughly twice the speed of normal solar wind, constantly streaming off the Sun.

When coronal holes are facing Earth, the solar wind can come in contact with Earth’s magnetic fields, creating geomagnetic disturbances around Earth that generate aurora.

SDO is designed to study the sun and its impacts on Earth. The spacecraft’s long-term measurements give scientists in-depth information to help characterize the interior of the sun, the sun’s magnetic field, the hot plasma of the solar corona, and the density of radiation that creates the ionosphere of the planets.

The Space Weather Prediction Center (SWPC) in Boulder, Colorado uses data from SDO and other spacecraft to monitor solar activity. SWPC uses the information to create better forecasts of space weather, which is necessary to protect aircraft, satellites, power grids, and astronauts living and working in space.

Current auroral oval. Image Credit: NOAA/Ovation

The OVATION Aurora Forecast Model shows the intensity and location of the aurora predicted for the time shown at the top of the map. This probability forecast is based on current solar wind conditions measured at L1, but using a fixed 30-minute delay time between L1 and Earth. A 30-minute delay corresponds to approximately 800 km/s solar wind speed as might be encountered during geomagnetic storming conditions. In reality, delay times vary from less than 30 minutes to an hour or so for average solar wind conditions.

SDO includes an instrument built in partnership with the University of Colorado at Boulder’s Laboratory for Atmospheric and Space Physics (LASP) and another built by Lockheed Martin Solar & Astrophysics Laboratory in Palo Alto, California.

Goddard built, operates and manages the SDO spacecraft for NASA’s Science Mission Directorate in Washington, D.C. SDO is the first mission of NASA’s Living with a Star Program.

SDO was launched on February 11, 2010 aboard a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral Air Force Station, Florida.