Small but ‘important’ asteroid spotted
A EUROPEAN team of astronomers – which includes a member from Alicante university – has detected a previously unknown asteroid measuring between 100 and 200 metres in diameter, using the NASA/ESA/CSA James Webb Space Telescope.
The object is located within the main asteroid belt, between Mars and Jupiter.
More observations are needed to better characterise this object’s nature and properties, according to the team.
They suspect it to be the smallest asteroid observed to date by Webb and one of the smallest detected in the main-belt.
According to a spokesperson for Alicante university, the find would – if confirmed as a new asteroid discovery – have ‘important implications for our understanding of the formation and evolution of the solar system’.
Current models predict the occurrence of asteroids down to very small sizes, but small asteroids have been studied in less detail than their larger counterparts owing to the difficulty of observing these objects.
Future dedicated Webb observations will allow astronomers to study asteroids smaller than one kilometre in size, ‘providing the necessary data to refine our models of the solar system’s formation’.
A ‘new technique’ has borne fruit in this case, using data generated by the James Webb telescope, which is Mid-Infrared Instrument (MIRI) calibration.
“We completely unexpectedly detected a small asteroid in publicly available MIRI calibration observations,” explained Thomas Müller, an astronomer at the Max Planck Institute for Extraterrestrial Physics in Germany.
“The measurements are some of the first MIRI measurements targeting the ecliptic plane and our work suggests that many, new objects will be detected with this instrument.”
Toni Santana-Ros, investigator at the institute of applied physics at Alicante university, said: “With the Webb, which is the largest and most powerful telescope ever launched into space, the object is visible with just a couple of minutes of observation.”
The team noted that the Solar System is teeming with asteroids and small rocky bodies.
Astronomers currently know of more than 1.1 million of these rocky remnants of the early days of the Solar System.
The James Webb Space Telescope’s ability to explore these objects at infrared wavelengths is expected to lead to groundbreaking new science, but a team of scientists have shown that Webb also has an unpredicted aptitude for serendipitously detecting small and previously unknown objects.
“Our detection lies in the main asteroid belt, but Webb’s incredible sensitivity made it possible to see this roughly 100-metre object at a distance of more than 100 million kilometres,” enthused Mr Müller.
In order to confirm that the object detected is a newly
discovered asteroid, more position data relative to background stars is required from follow-up studies to constrain the object’s orbit. The main asteroid belt is a doughnut-shaped region which contains the majority of the Solar System’s asteroids.
It lies roughly between the orbits of the planets Mars and Jupiter, and is closely aligned with the
ecliptic plane, the plane of the Earth’s orbit around the Sun, which is also the rough plane in which the other planets of the Solar System lie.
Webb is the largest, most powerful telescope ever launched into space.
Under an international collaboration agreement, ESA provided the telescope’s launch service, using the Ariane 5 launch vehicle.