“EPIC” Images Now Streaming Via DSCOVR Spacecraft

An Epic Image Credit NASA

An Epic Image
Credit NASA

On February 11, 2015, SpaceX conducted is first (and so far only) launch to deep space. The payload, officially designated as the Deep Space Climate Observatory, has a long and strange history dating back to the Clinton Administration and Vice President Al Gore’s proposal to launch a satellite which would show the entire Earth as seen from space on the internet 24 hours a day. The purpose was to highlight the planet’s fragile nature in a manner similar to the famous Apollo 8 “Earthrise” photograph which is credited with helping to spark the environmental movement.

After the bitterly contested presidential election of 2000, the incoming Bush Administration wanted to sweep aside much of the last 8 years, so the satellite, then named Triana after the lookout on Columbus’s ship who first spotted the new world, got shoved into a deep, dark space in Goddard’s closet. Doubtlessly some part of that time was spend in agonized self reflection over what would now be deemed a politically incorrect name in the first place.

Eight years later, and with political fortunes swinging back to the left, Triana got a new chance, a new life and a new name. Now called the Deep Space Climate Observatory or DSCOVR, it was pulled out, dusted off and re-purposed to serve as a weather buoy in deep space, with Earth imaging as a secondary function.

As a multi-agency spacecraft with a somewhat lower than average priority, DSCOVR was picked as the perfect candidate for a test launch by SpaceX to be conducted under the Air Force OSP-3 program, which is geared to accept a higher level of risk than EELV program payloads. In other words, if all this were taking place in the Star Trek universe, DSCOVR  would be wearing a red shirt, and might be gone by the first commercial break.

Fortunately, that did not happen. When launch day finally arrived 16 years late, the SpaceX Falcon 9 performed flawlessly, placing the spacecraft precisely on the intended trajectory and on the path to the L-1 LaGrange point, where its sits gravitationally perched between the Earth and the Sun. The latter is of course the source of the space weather being observed, and if the big yellow ball goes boom, DSCOVR will be among the first to know.

Yesterday, NASA launched a new website which will perform much of the function once envisioned by Al Gore. The URL http://epic.gsfc.nasa.gov draws its name from the Earth Polychromatic Imaging Camera (EPIC) camera which will display images taken over the previous 36 hours.

From the NASA.gov description:

“The primary objective of NOAA’s DSCOVR mission is to maintain the nation’s real-time solar wind monitoring capabilities, which are critical to the accuracy and lead time of space weather alerts and forecasts from NOAA. NASA has two Earth-observing instruments on the spacecraft. EPIC’s images of Earth allow scientists to study daily variations over the entire globe in such features as vegetation, ozone, aerosols, and cloud height and reflectivity.

EPIC is a four megapixel CCD camera and telescope. The color Earth images are created by combining three separate single-color images to create a photographic-quality image equivalent to a 12-megapixel camera. The camera takes a series of 10 images using different narrowband filters — from ultraviolet to near infrared — to produce a variety of science products. The red, green and blue channel images are used to create the color images. Each image is about 3 megabytes in size.

“The effective resolution of the DSCOVR EPIC camera is somewhere between 6.2 and 9.4 miles (10 and 15 kilometers),” said Adam Szabo, DSCOVR project scientist at NASA’s Goddard Space Flight Center, Greenbelt, Maryland.

Since Earth is extremely bright in the darkness of space, EPIC has to take very short exposure images (20-100 milliseconds). The much fainter stars are not visible in the background as a result of the short exposure times.

The DSCOVR spacecraft orbits around the L1 Lagrange point directly between Earth and the sun. This orbit keeps the spacecraft near the L1 point and requires only occasional small maneuvers, but its orbit can vary from 4 to 15 degrees away from the sun-Earth line over several years.”

For daily images from EPIC, visit:

http://epic.gsfc.nasa.gov/

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