About Smart Lander for Investigating Moon (SLIM) spacecraft
- It is a spacecraft built and launched by the Japan Aerospace Exploration Agency (JAXA) on September 7, 2023, from the Tanegashima spaceport.
- It weighed only 590 kg.
- It was launched together with XRISM, a next-generation X-ray space telescope, onboard an H-2A rocket.
- It entered into an elliptical orbit around the moon over three minutes or so.
- Its apogee (farthest point) in this orbit is 4,000 km and perigee (closest point) is 600 km above the lunar surface.
What will SLIM do on the moon?
- Just before it lands, SLIM will deploy two small rovers called Lunar Excursion Vehicle (LEV) 1 and 2. LEV-1, LEV-2, and SLIM will together study the lunar surface near the landing point, collect temperature and radiation readings, and attempt to study the moon’s mantle.
Key points about XRISM Mission
- The X-Ray Imaging and Spectroscopy Mission (XRISM) is a joint mission of the Japan Aerospace Exploration Agency (JAXA) and the National Aeronautics and Space Administration (NASA), involving contributions from the European Space Agency (ESA) and Canadian Space Agency as well.
- Objective: The mission aims to observe X-rays coming from deep space and to identify their wavelengths with unprecedented precision.
- It will use state-of-the-art spectroscopy to measure changes in the brightness of celestial objects at different wavelengths.
- It detects X-rays with energies ranging from 400 to 12,000 electron volts. (For comparison, the energy of visible light is 2 to 3 electron volts.)
- This range will provide astrophysicists with new information about some of the universe’s hottest regions, largest structures, and objects with the strongest gravity.
Q1) What are X-rays ?
These are a form of electromagnetic radiation, similar to visible light. Unlike light, however, x-rays have higher energy and can pass through most objects, including the body. Medical x-rays are used to generate images of tissues and structures inside the body.
Source: How Japan’s moon-landing attempt in January will affect Chandrayaan 4 | Explained
Last updated on Sep, 2026
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