RAVAN CubeSat has Front Row Seat to Solar Eclipse

RAVAN CubeSat has Front Row Seat to Solar Eclipse
Andrea Martin, September 2017, andrea.s.martin@nasa.gov


On August 21, 2017 RAVAN observed the Sun during solar eclipse. Here, an artistic rendering depicts RAVAN’s view just prior to the event. (Credit: NASA ESTO)

While people across the nation gazed at August’s solar eclipse from the Earth, an ESTO-funded satellite had a historic seat for the astronomical event.

RAVAN, the Radiometer Assessment using Vertically Aligned Nanotubes CubeSat, was developed to test and validate a new way of measuring Earth’s radiation imbalance. Now in orbit, RAVAN is utilizing light-absorbing carbon nanotubes to help detect even the smallest changes in energy being emitted from the planet.

But on August 21, 2017, those highly-sensitive nanotubes were used instead to detect changes in energy – in this case light – coming from the Sun during the eclipse. As the Moon passed between the Earth and the Sun, RAVAN’s instruments responded rapidly and accurately to measure the diminishing solar energy that was visible to the satellite’s detectors.

Due to RAVAN’s position in orbit, it was not able to witness totality – the moment when the Moon completely blocks the Sun’s light. Instead, from its path high above the US, RAVAN was able to image an approximately 80 percent eclipse, similar as to what was observed from Principal Investigator Bill Swartz’s home organization, the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland.

Because the researchers knew the CubeSat’s location and the percentage of eclipse it should be able to measure, it was easy to compare the data to the known solar irradiance, providing a good test of the instrument’s response to rapidly changing energy.

The data plotted here were collected by one of RAVAN’s innovative carbon nanotube (CNT) radiometer sensors. The plot shows that these sensors can rapidly respond to changes in the Sun’s (or Earth’s) irradiance. Sun graphics depict the extent of eclipse during the observation.
(Credit: Bill Swartz, Johns Hopkins APL)

By making time to witness the eclipse, RAVAN took advantage of yet another test of the sensitivity of carbon nanotube detector technology. Improved technology like this is necessary to identify even slight variations in Earth’s energy imbalance, an important variable in climate and weather.

Now, with eclipse-tested technology, RAVAN is back to looking at the Earth. Using its instruments to study the radiation being emitted from our dynamic planet, RAVAN’s technology advancements are pushing what is possible from a small satellite just a little bit more.

To learn more about RAVAN and its mission, see this NASA web feature:
RAVAN CubeSat Measures Earth’s Outgoing Energy