On Sept. 9, 2021, a sounding rocket launched from the White Sands Missile Range in New Mexico, carrying a copy of the Extreme Ultraviolet Variability Experiment, or EVE. This flight was used to calibrate the identical version of EVE that has flown in space since 2010 aboard NASA’s Solar Dynamics Observatory (SDO). Over the years, the space-based EVE has become degraded by intense sunlight, so scientists fly periodic calibration missions to keep EVE’s measurements sharp.
This highlight reel shows a selection of footage from the EVE sounding rocket flight and payload recovery, played at different speeds to highlight different parts of the flight. See the same footage in real-time on NASA’s Scientific Visualization Studio.
00:00 - 00:02 Real-time footage.
00:03 - 00:12 Slowed down to quarter speed (0.25x) to show the launch. The shadow of the rocket and the exhaust plume behind it are visible.
00:12 - 00:28 Sped up twenty times faster (20x). Data is not taken during this time while the rocket flies towards space. The white patch visible on the ground is White Sands National Park.
Why is the rocket spinning? These rockets use solid fuel. That means that any irregularities in the density cause the rocket to have a little more thrust in one direction. If nothing was done, this would mean the rocket would start veering off course. By spinning it the rocket, any bit of thrust that isn’t perfectly aligned with the long axis of the rocket gets averaged out: There’s a little too much thrust to the front, then to the left, then to the back, then to the right, over and over. The team uses controllable fins and sensors and software that can guide the rocket to go north along the range, rather than some other direction.
00:27 Two thin lines pop out in the aft view. Those are cables with weights on the end. Just like a spinning ice skater moving their arms out, they slow the spin.
00:28 - 00:49 Sped up to 2x. The second stage motor (Black Brant) gets ejected and falls back to the missile range. It’s the black thing tumbling below in the aft view.
00:49 - 01:03 Sped up to 30x. The rocket orients itself so that the instruments are pointing at the Sun and the shutter door is opened. This is when measurements are taken. Pointing control here is extremely good: about one arcsecond pointing accuracy, which is like being in LA and landing a laser on the Washington Monument.
01:03 - 01:11 Sped up to 20x. The shutter door is closed, and the rocket is intentionally tumbled. The rocket is re-entering the atmosphere, so if any one spot of the rocket was constantly taking the brunt of the friction from air, it would do serious damage. Tumbling spreads out that heat load.
01:11 - 01:25 Real-time, and then sped up to 4x. The drogue, and then the parachute, are deployed.
01:25 - 01:33 Real-time. In the aft view, you can see the shadow of the rocket and the parachute.
01:33 - 01:34 Sped up to 8x. Coming down.
01:40 - 02:16 Footage is played at various speeds while the team recovers the payload.
02:16 - end: This is what some of the data looked like. The yellow-tinted movie of the Sun is from the Atmospheric Imaging Assembly instrument on NASA’s Solar Dynamics Observatory, and shows what the Sun looked like during the flight at one of the wavelengths measured (17.1 nm). This rocket flight was to calibrate a different instrument – EVE – on SDO, which is then also used to calibrate the Atmospheric Imaging Assembly.
Video and annotation credit: NASA/University of Colorado Boulder, Laboratory for Atmospheric and Space Physics/James Mason
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 188.8.131.52.0