NEOMIR: A Planetary Defense Mission to Find Dangerous Asteroids Hidden by the Sun

NEOMIR: A Planetary Defense Mission to Find Dangerous Asteroids Hidden by the Sun ...

The NEOMIR orbiting observatory will serve as an early warning system to detect and monitor any asteroid coming towards Earth from the Sun's direction at the first Lagrange point (L1). NEOMIR will be placed between the Sun and Earth at the first Lagrange point (L1), and will detect near-Earth objects with a diameter of more than 20 meters at least three weeks ahead of any Earth impact. Credit: ESA / Pierre Carril

Asteroids, like stars, come out only late at night. A large number of asteroids are hidden under the glare of our Sun, many of whom are unknown, some of whom might be heading toward Earth, and we just don't know it.

The NEOMIR mission, planned by the European Space Agency, will be situated between Earth and the Sun and will serve as an early warning system for asteroids 20 meters or larger that are unobservable from the ground.

The Chelyabinsk meteor of February 15, 2013, was unveiled by anyone. A 20-meter (66-foot) asteroid hit the atmosphere near the Ural Mountains in Russia just after sunrise on a calm and sunny winter day, at a speed of more than 18 kilometers per hour.

Fallen trees in Tunguska, Imperial Russia, seen in 1929, 15 km from the epicenter of an aerial blast site, caused by an explosion of a meteor in 1908. Credit: Photo N. A. Setrukov, 1928

The relatively tiny rock approached Earth from very close to the Sun's arc, bursting into the atmosphere and causing a shockwave that caused damage to tens of thousands of structures, breaking windows, and killing around 1500 people from flying glass fragments. It was the largest asteroid to strike Earth in more than a century.

Asteroids this size are expected to strike Earth once every 50 to 100 years, but smaller asteroids are less likely, although they do much more harm than dinosaurs. These are, however, much easier to detect.

The dangers of anasteroid are explained. Credit: ESA, CC BY-SA 3.0 IGO

Small and medium-sized asteroids are more common, and can still cause significant damage, but just a few days before you tell the public to keep away from windows or even to evacuate a local area.

NEOMIR will fill a gap in ESA's current asteroid detection capabilities, whether it's deflecting a large asteroid years in advance or providing data for local authorities to keep communities informed of airbursts weeks ahead.

Asteroids are visible because they reflect the Sun's light, which we can detect from Earth. However, the closer they get to the Sun, the harder they are to see. Asteroids near the Sun are particularly difficult to detect, but from Earth, we are also blind to asteroids near the Sun because they are completely obscured by the sun's glare.

Satellites may be orbiting Earth or reaching deep space with less 'orbital maintenance' than those who orbit Earth or fly out to deep space. Credit: ESA

The next NEOMIR mission from ESA will be launched into orbit around the first Lagrange point (L1) between the Sun and Earth, retaining the same position relative to the two bodies. This will give the telescope an insight into asteroids that may come towards the Earth from the direction of the Sun.

NEOMIR will monitor a remote ring around the Sun that is difficult to spot from the ground due to its proximity to Earth's distorting atmosphere. Any asteroids that we cannot currently see will have to pass through this ring.

Stijn Thoolen, an ESA-sponsored medical doctor who studied Antarctic summer at a Concordia research station, shows us our brightly burning Sun. Credit: ESA/IPEV/PNRA–S. Thoolen

NEOMIR will be able to see closer to the Sun thanks to observations in the infrared part of the light spectrum. This heat isn't drowned out by sunlight.

NEOMIR should detect asteroids 20 meters (66 feet) or larger that are headed toward Earth at least three weeks in advance. In the worst-case scenario, if the asteroid is spotted near the spacecraft, we would get a minimum of three days' warning, the fastest the asteroid could go from L1 to Earth.

Details of the NEOMIR mission of the Space Safety Program are being developed, and it is anticipated to launch around 2030 with an Ariane 6-2 rocket.

Ariane 6's configuration using four boosters (A64) is shown in an artist's perspective (ESA) – D. Ducros

In 2021, ESA's Concurrent Design Facility in the Netherlands conducted an initial study to evaluate the feasibility of the NEOMIR mission. The mission would complement NASA's NEO Surveyor mission, which should discover 90% of near-Earth objects larger than 140 meters (460 feet) in diameter.

NEOMIR is in the early planning stage of its mission. It will require a half-meter telescope with a large, corrected focal plane as well as two infrared channels covering light in the 5-10 micrometer waveband.

In September 2022, NASA's DART spacecraft collided with the smaller body of the Didymos binary asteroid system. To develop a practical planetary defense technique, the ESA's Hera mission will survey the 'Didymoon' after impact and examine how its orbit has been altered as a result of the collision.

The required detector technologies and associated electronics for this unique mission are currently being developed. Industrial research and development activities will be supported in parallel.

The goal is to obtain a comparable performance to the 'NEO Surveyor detectors,' such as Teledyne's HxRG, used in the James Webb Space Telescope (NIRSpec) and ESA's Euclid (NISP) and Ariel missions.

You may also like: