NASAs Lucy mission, which released on October 16, 2021, for the first reconnaissance of the Trojans, a population of primitive asteroids orbiting in tandem with Jupiter. In this artists concept (not to scale), the Lucy spacecraft is flying by Eurybates, among the six scientifically important and varied Trojans to be studied. Credit: Southwest Research Institute
The Lucy operations group has actually validated that NASAs Lucy spacecraft has phoned home after its encounter with the small main belt asteroid, Dinkinesh. Based upon the details received, the team has identified that the spacecraft remains in excellent health and the team has commanded the spacecraft to start downlinking the data collected during the encounter. It will take up to a week for all the data collected throughout the encounter to be downlinked to Earth. The group is eagerly anticipating seeing how the spacecraft performed throughout this very first in-flight test of a high-speed asteroid encounter.
Asteroid Encounter Test
Dinkinesh, a little inner-main belt asteroid, is 10 to 100 times smaller than the Jupiter Trojan asteroids that are the missions primary targets. The Dinkinesh encounter functions as a first in-flight test of the spacecrafts terminal tracking system.
Lucys closest approach occurred at 12:54 p.m. EDT (16:54 UTC) at a distance within 270 miles (430 km) of Dinkinesh. However, there wasnt much time to observe the asteroid at this distance as Lucy sped previous at 10,000 mph (4.5 km/s).
The Lucy operations team has actually verified that NASAs Lucy spacecraft has telephoned home after its encounter with the small main belt asteroid, Dinkinesh. Based on the information got, the group has determined that the spacecraft is in great health and the group has actually commanded the spacecraft to begin downlinking the information gathered throughout the encounter. The spacecrafts terminal tracking system is created to actively keep an eye on the area of Dinkinesh, making it possible for the spacecraft and IPP to move autonomously in order to observe the asteroid throughout the encounter. The spacecrafts terminal tracking system is designed to actively keep track of the place of Dinkinesh, enabling the spacecraft and IPP to move autonomously in order to observe the asteroid throughout the encounter. After evaluating the health and security of the spacecraft, the team commanded the spacecraft to start downlinking the data taken during the encounter.
This graphic highlights the predicted movement of the NASA Lucy spacecraft and its instrument pointing platform (IPP) throughout the encounter with asteroid Dinkinesh. The spacecrafts terminal tracking system is developed to actively keep an eye on the location of Dinkinesh, allowing the spacecraft and IPP to move autonomously in order to observe the asteroid throughout the encounter. The yellow, blue, and grey arrows suggest the directions of the Sun, Earth, and Dinkinesh, respectively. The red arrow suggests movement of the spacecraft. Credit: NASA/Goddard/SwRI
Encounter Configuration and Data Collection
2 hours before closest method, the spacecraft and the rotational platform that holds Lucys science instruments (the instrument pointing platform) were commanded to move into encounter setup. After this point, the spacecrafts high-gain antenna pointed away from the Earth and the spacecraft was unable to return data for the remainder of the encounter.
Shortly thereafter, the high-resolution grayscale camera on Lucy, LLORRI, started taking a series of images every 15 minutes. (LLORRI, short for Lucys Long Range Reconnaissance Imager, was supplied by the Johns Hopkins Applied Physics Laboratory.) When the group started utilizing the instrument to assist with spacecraft navigation, Dinkinesh has actually been visible to LLORRI as a single point of light considering that early September. The team approximates that at a range of simply under 20,000 miles (30,000 km), Dinkinesh might seem a few pixels in size, just hardly fixed by the video camera.
This animation shows the anticipated motion of the NASA Lucy spacecraft and its instrument pointing platform (IPP) during the encounter with asteroid Dinkinesh. The spacecrafts terminal tracking system is designed to actively keep an eye on the place of Dinkinesh, enabling the spacecraft and IPP to move autonomously in order to observe the asteroid throughout the encounter. Credit: NASA/Goddard/SwRI
Instrument Observations and Closest Approach
In addition, Lucys thermal infrared instrument, LTES, began gathering data. LTES (formally the Lucy Thermal Emission Spectrometer, supplied by Arizona State University) was not designed to observe an asteroid as little as Dinkinesh, so the group is interested to see if LTES was able to spot the asteroid and determine its temperature throughout the encounter.
The spacecraft used T2Cam (the Terminal Tracking Cameras, supplied by Malin Space Science Systems), to consistently image the asteroid. In the minutes around closest technique, this system is designed to autonomously reorient the spacecraft and its instrument pointing platform as required to keep the asteroid focused in the video cameras field of view.
Advanced Imaging and Post-Encounter Maneuvers
Ten minutes before closest technique, the spacecraft was instructed to begin “closest approach imaging” with the LLORRI instrument. In these images, taken every 15 seconds at three various exposure times, the asteroid will be a number of hundred pixels across, allowing the group an unprecedented view of this small main belt asteroid, which is approximated to be less than half a mile (1 km) in diameter.
Lucy waited up until about 6 minutes before closest method to begin taking data with its color imager (the Multi-spectral Visible Imaging Camera, MVIC) and infrared spectrometer (Linear Etalon Imaging Spectral Array, LEISA), which together comprise the LRalph instrument (offered by NASAs Goddard Space Flight Center in Greenbelt, Maryland).
About 6 minutes after the closest approach, LRalph stopped taking data, and Lucy concluded the closest method observations. By this time, the spacecraft was already almost 1,700 miles (2,700 km) past the asteroid. Lucy then started a maneuver described as a “pitchback” in which it reorients its solar ranges toward the Sun while the instrument pointing platform continues to autonomously track the asteroid as the spacecraft leaves. This maneuver was developed to be performed gradually to decrease spacecraft vibrations as the spacecraft moves its big solar varieties. LLORRI imaged Dinkinesh throughout this process to keep an eye on spacecraft stability.
Data Transmission and Observations Continuation
When the spacecraft was over 8,000 miles (13,000 km) from the asteroid, Lucy stopped actively tracking the position of Dinkinesh. From that point on, the team anticipates the asteroid to remain visible to the spacecrafts cameras without the need to rearrange the spacecraft or instruments.
Two hours after closest approach, the LTES instrument was instructed to stop taking data. LLORRI will continue regularly observing the asteroid for another 4 days to keep track of the light curve of the asteroid.
When Lucy turns its high-gain antenna back towards Earth, it will be able to resume communications, with a roughly 30-minute light-travel-time hold-up in each direction. The team got the first signal from the spacecraft within two hours of closest technique. After evaluating the health and safety of the spacecraft, the group commanded the spacecraft to begin downlinking the data taken throughout the encounter. It will take up to a week for all data to be returned to Earth through NASAs Deep Space Network.
