Japan's Hayabusa2 Spacecraft Breaks New Ground with Laser Ranging

Topic: Space

The Japan Aerospace Exploration Agency's (JAXA) Hayabusa2 spacecraft has successfully conducted a laser-ranging experiment on asteroid Torifune. This milestone will help space agencies better understand near-Earth asteroids and other deep-space objects.

On July 5, the Hayabusa2 spacecraft flew by asteroid Torifune, marking the first time a space agency has attempted a laser-ranging experiment during a flyby. The mission team used the LIDAR laser altimeter instrument to measure distances between the spacecraft and the asteroid. This instrument was developed from the Light Detection and Ranging (LIDAR) altimeter used by JAXA's Kaguya lunar orbiter.

The LALT instrument is special because it can not only measure distances but also determine an asteroid's density, porosity, surface reflectance, and even detect levitating dust particles. The team successfully fired the laser twice, at 6:29 p.m. (2:29 a.m. PDT; 5:29 a.m. EDT), from distances of about 20 km and 15 km (12.5 miles and 9.3 miles) before the flyby.

This experiment was challenging because the laser had to be directed at a small target while the spacecraft traveled at 5.3 km/s, or 18,000 km/h (3.3 mi/s or 11,185 mph). The mission team had to prepare extensively to ensure accurate targeting and avoid background noise.

Laser ranging is an important technique because it helps scientists determine a celestial body's position and trajectory. This information can be used for planetary defense by predicting which asteroids could pose a potential future collision risk.

Why It Matters

This achievement has implications for India's space program, as well as the country's efforts to track near-Earth asteroids that could potentially collide with our planet.

Key Facts

• The Hayabusa2 spacecraft successfully conducted a laser-ranging experiment on asteroid Torifune on July 5.
• The LIDAR laser altimeter instrument was used for the experiment, which can measure distances and determine an asteroid's density, porosity, surface reflectance, and detect levitating dust particles.
• The mission team fired the laser twice from distances of about 20 km and 15 km (12.5 miles and 9.3 miles) before the flyby.
• Laser ranging is a technique that helps scientists determine a celestial body's position and trajectory.
• This achievement has implications for planetary defense by predicting which asteroids could pose a potential future collision risk.

Key Terms

LIDAR

Light Detection and Ranging, an instrument used to measure distances and detect objects in space

Near-Earth asteroid (NEA)

An asteroid that orbits the Sun at a distance close enough for it to potentially collide with Earth

Implications

This achievement has implications for India's space program, as well as the country's efforts to track near-Earth asteroids that could potentially collide with our planet.