Solar Dynamics Observatory
By Danny Baird
August 21, 2017
This blog post was written prior to a reorganization of ESC’s projects and networks in support of the agency’s commercialization effort. Though accurate at the time of publication, it is no longer being updated and may contain broken links or outdated information. For more information about the reorganization, click here.
The forecast for today? At NASA’s Goddard Space Flight Center, a balmy 82 degrees Fahrenheit; on the surface of the sun, a blistering 9,941.
Meteorologists on Earth have long studied Earth’s climate and weather systems. Nowadays, one can turn on the nightly news and expect to be reasonably prepared for the next day’s weather. Though meteorology can be unpredictable, Earth has a relatively stable climate and humankind has gotten reasonably good at forecasting the weather. At NASA, however, we don’t just study Earth’s weather; we also study something much more complex: space weather.
NASA’s Solar Dynamics Observatory, or SDO, orbits Earth above the Pacific Ocean. The satellite beams 150 million bits of data per second about weather that originates within our sun. Giant eruptions from the sun, solar flares and coronal mass ejections, can spread out into space, often towards Earth. They can disrupt radio communications, trip electronics onboard satellites and even affect utility grids on the ground. A growing understanding of space weather could improve our ability to predict it, mitigating some of its effects. NASA’s SDO is a key part of that effort, allowing for constant observation of the sun and enabling researchers to better understand the causes of solar flares and coronal mass ejections. During the 2017 solar eclipse, the moon blocks SDO’s view of the sun’s bright center for 28 minutes, but gives a view of the corona that cannot be replicated by human instruments.
A dedicated ground station in White Sands, New Mexico receives SDO’s data. This station, part of NASA’s Near Earth Network, operates 24/7 all year long. A pair of high-gain antennas aboard SDO communicate with two 18-meter antennas on the ground. The Swedish Space Corporation provides additional telemetry support with its 13-meter antenna in South Point, Hawaii. These antennas operate across the spectrum, providing telemetry and command over S-band and science data over Ka-band.
“By some estimates, SDO will transmit as much as 50 times more science data than any mission in NASA history,” said Dean Pesnell, project scientist of SDO at NASA’s Goddard Space Flight Center, in a quote from “Our Eye on the Sun: A Guide to the Mission and Purpose of NASA’s Solar Dynamics Observatory.”
Using that data, SDO provides the most complete picture of the sun’s variable activity. We can’t yet predict space weather with the same accuracy as the weekly forecast, but the data from the Solar Dynamics Observatory and the NASA’s research into space weather models and simulations may make such a future possible.