NASA/Johns Hopkins APL image of the DART spacecraft.
The Double Asteroid Redirection Test's (DART) camera captured images of Vega, one of Earth's night sky's brightest stars, and recently observed Jupiter's four largest moons.
The DART spacecraft is currently on its way to the highly anticipated September 26 encounter with the binary asteroid Didymos. During the journey, the spacecraft's imager — the Didymos Reconnaissance and Asteroid Camera for Optical Navigation (DRACO) — has taken thousands of photographs of stars. These images help NASA's ongoing spacecraft testing and rehearsals in preparation for the spacecraft's kinetic impact on Dimorphos, the moon of Didymos.
On May 27, NASA/Johns Hopkins APL's high-resolution camera DRACO captured this image of Vega, one of the night sky's brightest stars at just 25 light years away. The six spikes around the star are the result of light bouncing off the structure that holds DRACO's second mirror in place.
DRACO is the only instrument on DART that will allow you to see Didymos and Dimorphos, but it will also support the Small-body Maneuvering Autonomous Real Time Navigation (SMART Nav), which is the spacecraft's autonomous guidance system that will guide DART to impact.
On July 1 and August 2, the mission operations crew pointed the DRACO imager toward Jupiter. This was similar to how Dimorphos will visually separate from the larger asteroid Didymos in the hours leading up to impact. However, the test gave the APL-led SMART Nav team the opportunity to examine how well the SMART Nav system performs in flight.
A cropped version of a DRACO image centered on Jupiter taken during one of SMART Nav's tests. DART was about 16 million miles (26 million km) from Earth when the image was taken, with Jupiter about 435 million miles (700 million km) away from the spacecraft. Credit: NASA/John Hopkins APL
The SMART Nav crew gained valuable experience, including knowledge of how the SMART Nav team interprets data from the spacecraft. “Every time we do one of these tests, we tweak the displays, make them a little bit better and a little bit more responsive to what we will need during the actual terminal event,” said Peter Ericksen, APL's SMART Nav software engineer.
The SMART Nav team will continue to monitor objects as they are tracked in the scene, including their intensities, the number of pixels, and how consistently they’re being identified. Corrective action will be taken only if significant and mission-threatening deviations are observed. With Jupiter and its moons, the team had a chance to better understand how the intensities and number of pixels of objects might vary as they move across the detector.
The image above is a cropped composite of a DRACO image centered on Jupiter taken during one of these SMART Nav tests. DART was approximately 16 million miles (26 million km) from Earth and Jupiter was approximately 435 million miles (700 million km) away from the spacecraft. Two brightness and contrast stretches, made to optimize Jupiter and its moons, respectively, were combined to form this view.
"The Jupiter tests gave us the opportunity for DRACO to observe something in our own solar system," said Carolyn Ernst, DRACO instrument scientist at APL. "The images look fantastic, and we are eager for what DRACO will reveal about Didymos and Dimorphos in the hours and minutes leading up to impact!"
DRACO is a high-resolution camera developed by NASA's New Horizons spacecraft, which took the first close-up images of the Pluto system and the Kuiper Belt object Arrokoth.
The NASA Planetary Defense Coordination Office's Applied Physics Laboratory (APL) has developed and managed DART, the world's first planetary defense test mission, which will intentionally impact Dimorphos in order to modify its motion in space. However, the DART mission will demonstrate that a spacecraft may be capable of deflecting a dangerous object, if ever.