Arase (satellite)

Arase
	Artistic rendering of Arase in orbit.
Mission type	Earth observation
Operator	JAXA
COSPAR ID	2016-080A
SATCAT no.	41896
Mission duration	8 years, 5 months and 28 days (elapsed)
Spacecraft properties
Bus	SPRINT
Launch mass	~350 kg
Power	≧700 W
Start of mission
Launch date	11:00, December 20, 2016 (UTC)
Rocket	Epsilon
Launch site	Uchinoura
Orbital parameters
Reference system	Geocentric
Perigee altitude	~460 km
Apogee altitude	~32110 km
Inclination	~31 degrees
Period	~565 minutes
Instruments
	Extremely high-energy electron sensor (XEP-e); High-energy particle sensor – electron (HEP-e); Medium-energy particle sensor – electron (MEP-e); Low-energy particle sensor – electron (LEP-e); Medium-energy particle – ion (MEP-i); Low-energy particle – ion (LEP-i); Magnetic Field Experiment (MGF); Plasma Wave Experiment (PWE); Software Wave-Particle Interaction Analyzer (S-WPIA);

Arase, formerly known as Exploration of energization and Radiation in Geospace (ERG), is a scientific satellite to study the Van Allen belts. It was developed by the Institute of Space and Astronautical Science of JAXA. While there was a scientist working on a similar project with the surname Arase, the satellite's name has nothing to do with him but instead named after a river beside the launch point.

It was launched aboard Epsilon launch vehicle at 11:00:00, 20 December 2016 UTC into apogee height 32250 km, perigee 214 km orbit. Subsequent perigee-up operation moved its orbit to apogee 32110 km, perigee 460 km of 565 minutes period.