Suggested Searches

2 min read

Checking in on the Cameras of NASA’s Asteroids-Bound Lucy Spacecraft

The headshot image of Katy Mersmann

Katy Mersmann

Apr 11, 2022
Article
A ground-based starry night sky photo with rectangular boxes imposed, to represent frames of view of Lucy spacecraft cameras. A large red box is overlaid by a much thinner blue, rectangular box, representing two different fields of view. In the center of the red box, a tiny yellow box represents another field of view.
For this selection of images, Lucy’s Instrument Pointing Platform was pointed near the constellation Orion, and the T2CAM field included the Rosette Nebula. The red, blue, and yellow boxes indicate the frames of the T2CAM, MVIC, and L’LORRI images, respectively.
Credits: SwRI; 2008 file photo of night sky as seen over Fajada Butte in New Mexico, courtesy National Parks Service

On Feb. 14, NASA’s Lucy spacecraft, which is in the first few months of its journey to the Trojan asteroids, obtained a series of calibration images with its four visible-light cameras. The first test images were taken in November 2021, shortly after Lucy’s Oct. 16, 2021, launch, but the February test was much more extensive. Lucy used its Instrument Pointing Platform to point at 11 different star fields to test camera performance and sensitivity, as well as the spacecraft’s ability to point accurately in different directions.

The four cameras are the twin Terminal Tracking Cameras (T2CAM), the Multicolor Visible Imaging Camera (MVIC), and the Long-Range Reconnaissance Imager (L’LORRI). The T2CAM cameras have a wide field of view, 11 degrees by 8.2 degrees, and are primarily used to automatically lock onto and track the Trojan asteroids during Lucy’s close flybys, ensuring that the spacecraft’s other instruments are pointed at the target. MVIC, part of the L’Ralph instrument, is a higher-resolution color scanning camera that can scan its 8.3-degree-tall field of view across as wide a swath as desired, much like the panoramas taken by a mobile phone camera. L’LORRI is a high-resolution monochromatic telephoto camera with a narrow 0.29-degree-square field of view and will obtain Lucy’s most detailed images of its asteroid targets.

The test did not include Lucy’s infrared spectrometer LEISA (also part of the L’Ralph instrument) or its temperature mapping L’TES instrument, which requires close-up planetary targets to obtain useful data.

Grainy black-and-white view of stars filling the entire frame.
With an exposure time of 10 seconds, the Rosette Nebula is just visible in the lower right of center of the T2CAM frame.
Credits: NASA/Goddard/SwRI
Panorama-like black-and-white image, mostly black with a smattering of dim white stars. of stars
MVIC is a scanning multichannel imager, capable of taking multi-color or panchromatic images. This panchromatic image was acquired during a scan over a narrow part of the T2CAM field. The MVIC exposure time was 0.92 seconds, and the image was produced by partially subtracting the background, enabling us to see faint stars
Credits: NASA/Goddard/SwRI
Slightly grainy black-and-white view of stars. In the top left and bottom center, a few stars glow brightly with six pointed diffraction spikes.
The faintest visible stars in this raw L’LORRI image are roughly 17th magnitude, 50,000 times fainter than the unaided human eye can see. Image brightness levels have been adjusted to enhance visibility of faint stars. The exposure time was 10 seconds. Keen observers will notice that the stars are slightly elongated in this relatively unprocessed image; the Lucy team has techniques to mitigate this effect, and the optical quality is sufficient for accomplishing the science goals of the mission.
Credits: NASA/Goddard/SwRI/Johns Hopkins APL

By John Spencer, Southwest Research Institute

Media contact: Nancy Jones, NASA’s Goddard Space Flight Center, Greenbelt, Md.