When NASA’s DART spacecraft smashes into the asteroid Demorphos on Sept. 26, it will have a silent witness: an Italian cube called LICIACube will witness the ground-breaking real-time experiment of excited scientists on Earth.
LICIACubeor the Italian Light Asteroid Imaging Cube, is a small 31-pound (14 kg) satellite that has been able to ride Arrow (Double Asteroid Redirect Test) to DidymusDimorphos binary asteroid system. DART deployed the cubes on Sunday (September 11) at 7:14 PM EDT (2314 GMT) to give LICIACube 15 days to assume a safe position to monitor the collision of DART with Dimorphos. Impact is the first experiment of its kind designed to alter the orbit of a space rock in a crucial test of planetary defense A concept that might one day save the lives of millions of people on Earth.
“LICIACube will be launched from the distributor on one of the outer panels of DART, and will be directed (braking and rotating) to begin its autonomous journey toward Demorphos,” Elena Mazzuta Epifani, an astronomer at the Italian National Institute of Astrophysics (INAF) told SPACE LICIACube mission co-investigator. .org in an email. “The cubes will point their cameras at the asteroid system, but also at DART, and maybe they’ll take some pictures of them.”
The only direct witness
Equipped with two optical cameras, LICIACube will follow DART toward Dimorphos and eventually settle down to watch the drama from a safe distance of 600 miles (1,000 km) as the 1,345-pound (610-kg) spacecraft hits the rock on September 26, Mazzotta Epifani added. The effect of DART . will be [seen] as an increase in the brightness of the subject by comparing images of Dimorphos taken before and after the effect.”
At the time of the collision, Demorphos and Didymos will be approximately 6.8 million miles (11 million kilometers) from Earth, According to NASA (Opens in a new tab). Although Earth-centric astronomers won’t be able to see the impact, they will monitor the system closely in the following weeks to determine if the 12-hour orbit of the 560-foot (170-meter) Dimorphos is about 2,600 feet wide. (800 AD) Didymus will be accelerated as expected. They will do this by measuring the intervals between the brief blackouts that occur at the two asteroids eclipse each other.
But while such observations may be enough to confirm the success of the experiment, they will not provide any details of the effects of the DART impact on the asteroid. Thus, right after DART hits the Dimorphos, LICIACube will approach to inspect the scene.
“LICIACube… will perform a ‘fast fly’ approximately 3 minutes after the DART impact over a distance of at least 55 km. [34 miles] Mazzotta Epifani wrote from the surface of Dimorphos at its closest point. “Image acquisition by the two onboard cameras will last approximately 10 minutes and will be assigned to the target effect and non-impact aspects, as well as a column of the DART effect.”
LICIACube will then send the images to a landBut Mazzatta Epifani cautioned that it could take weeks to get all the data.
We don’t know anything about Dimorphos
Understanding the effects of the DART impact on Dimorphos at depth is critical as a similar system may one day be needed to drain rocks on a collision course with Earth. An asteroid the size of Demorphos could destroy the entire continent while an impact of one the size of Didymos larger could be felt all over the world.
But there’s a catch: Although astronomers know in detail the orbits of most of the 26,115 near-Earth asteroids (of which 2,000 have been classified as “potentially dangerous” due to their size and closest approach to Earth), surprisingly little about these. rocks. In particular, scientists do not understand the density of the material that the rocks are made of and can only guess how the surface might behave upon impact.
The team behind NASA’s OSIRIS-REx missionthat reached the nearby land asteroid benno In October 2020, I experienced firsthand the pitfalls of this unknown. The asteroid’s unexpectedly smooth surface nearly swallowed the spacecraft, and the landing generated what OSIRIS-REx Principal Investigator Dante Loretta described as ‘A huge wall of debris’ Which could have easily destroyed the spacecraft.
Loretta, a planetary scientist at the University of Arizona, Tell Space.com When the accident was announced, he indicated that trying to deflect may be more difficult than thought, because asteroids with smooth surfaces can absorb the shock.
The team behind DART knows as little about Demorphos as the OSIRIS-Rex team knew about Bennu before the spacecraft reached the asteroid. The images, captured by DART itself before and after the impact by LICIACube, will be the first-ever detailed views of Dimorphos astronomers.
“We know the general surface characteristics of the larger Didymus, thanks to spectroscopic and ground-based photometric measurements, but we know almost nothing about Demorphos, which is too small to produce an effect separate from the impact coming from the main body,” Mazzuta Epifani wrote. “We *assume* from theoretical models about the formation of binary asteroids that Dimorphos are very similar to Didymos, but we know almost nothing about the degree of cohesion of surface materials, the size distribution of surface debris, etc.”
Scientists believe Demorphos is a so-called “rubbish-pile asteroid” like Bennu: an agglomeration of rock and dirt that once separated from the main asteroid Didymos, and is now only tightly held together. gravity. Since the asteroid is rather small, this force is very weak. For this reason, astronomers don’t understand what effect DART will have, how much matter it will eject into space, and how big a crater it might leave behind.
Lessons for the future
“Together for the first time in high detail, DART and LICIACube will analyze the physical properties of a binary near-Earth asteroid, allowing us to investigate its nature and obtain hints about its formation and evolution,” Mazzuta Epifani wrote. “LICIACube will get multiple images of the output shaft resulting from the same effect as the DART effect [crater] size, as well as an unaffecting hemisphere to help us study the size and morphology of the crater and the effects on surface properties in the surrounding areas.”
The good news is that the more information scientists gather, the better they can predict the effects of potential future interventions on similar asteroids.
Mazuta Epifani wrote that the Italian Space Agency, which oversees the LICIACube mission, is currently assessing plans to extend the mission for further studies of the Didymos-Dimorphos binary asteroid system, adding that any decisions about extending the mission beyond the direct repercussions of the collision only after Sept. 26.
Italy’s first deep space mission
For the Italians, who have a thriving space industry that has contributed to some of Europe’s most iconic space projects (including the European Columbus module of the International Space Station), LICIACube is the first deep space mission the country will have on its own. Developed and built in less than three and a half years, LICIACube is similar to ArgoMoon, one of the Cubes that cut a trip to the moon on NASA Artemis mission 1who still Waiting for take off After a fuel leak halted an attempted launch on September 3.
“LICIACube is not only the first deep space mission that Italy will operate, but also the first to be entirely designed, implemented and managed in Italy, including data reception and management,” Mazzuta Epifani wrote.
With LICIACube, Italy stepped in to fill the gap caused by the delay in budget approval in the European Space Agency (ESA) HERA . missiona much larger spacecraft, which was originally intended to reach the Didymos-Dimorphos duo before the DART effect to examine the system and then monitor the crash and study its repercussions in detail. ESA still plans to launch HERAHowever, the spacecraft will not reach Didymos until 2027.