ALOS-4

H3's first operational flight, after the VEP-4 test flight in February 2024, put the Japanese radar-imaging satellite ALOS-4 (Daichi 4) into orbit. It succeeded ALOS-2 (launched 2014) for the Japan Aerospace Exploration Agency (JAXA).

ALOS-4 carries PALSAR-3, an L-band radar that images the ground in any weather and at night. It resolves 3 m over a 200 km swath, four times wider than ALOS-2 at that resolution, so it can cover all of Japan 20 times a year instead of four. The images support disaster response, forest monitoring and sea-ice tracking.