Super Low Altitude Test Satellite
Super Low Altitude Test Satellite (SLATS) or Tsubame is a JAXA satellite intended to demonstrate operations in very low Earth orbit (VLEO, below 200 km), using ion engines to counteract aerodynamic drag from the Earth's atmosphere which is substantial at such lower orbital altitudes. It was launched on 23 December 2017, and decommissioned on 1 October 2019.

The spacecraft is equipped with sensors to determine atomic oxygen density, an exposure facility to measure material degradation in the 200 km orbit, and a small camera. Initial designs had conventional, though slightly canted, solar panels (compare to the aerodynamic shape and on-body solar panels of GOCE, which flew in a 255 km orbit). SLATS received the nickname Tsubame (Japanese for barn swallow) on 14 July 2017. According to JAXA, this name was chosen as the thin, elongated satellite in super low orbit with a set of solar array wings is reminiscent of a small swallow flying low.

SLATS was launched 23 December 2017 on a H-IIA rocket alongside the GCOM-C (Shikisai) satellite to a 630 km orbit, followed by orbit-lowering manoeuvres by a combination of chemical propulsion and aerobraking, with final operation at an altitude below 180 km.

SLATS was operated at 7 altitudes: 271.5 and 216.8 km each for 38 days, and 250, 240, 230, 181.1 and 167.4 km each for 7 days. At 167.4 km the RCS thrusters were used in addition to the ion thruster to maintain altitude.

The operation of the satellite was finished on 30 September 2019, and it was decommissioned in orbit on 1 October 2019 by terminating the communication radio and power.

On 30 December 2019, Guinness World Records recognized Tsubame's achievement, which reached the lowest altitude ever among Earth observation satellites.
Q179103
JAXA
ORG
Q663611
very low Earth orbit
Concept
Q205702
ion engine
Concept
Q206621
drag
Concept
Q3230
Earth's atmosphere
Concept
Q1579577
orbital altitude
Concept
Q428653
atomic oxygen
Concept
Q774583
solar panel
Concept
Q258697
GOCE
MISC
Q25429
barn swallow
Concept
Q60599
H-IIA rocket
MISC
Q3108984
GCOM-C
MISC
Q335225
chemical propulsion
Concept
Q16353
aerobraking
Concept
Q41675
Guinness World Records
MEDIA
Q22084833
Super Low Altitude Test Satellite
MISC
2017-12-23T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
23 December 2017
DATE
2019-10-01T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
1 October 2019
DATE
2017-07-14T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
14 July 2017
DATE
2017-12-23T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
23 December 2017
DATE
2019-09-30T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
30 September 2019
DATE
2019-10-01T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
1 October 2019
DATE
2019-12-30T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
30 December 2019
DATE
+7^^http://www.w3.org/2001/XMLSchema#decimal
7
NUMBER
+271.5^^http://www.w3.org/2001/XMLSchema#decimal
271.5
NUMBER
+216.8^^http://www.w3.org/2001/XMLSchema#decimal
216.8
NUMBER
+38^^http://www.w3.org/2001/XMLSchema#decimal
38
NUMBER
+181.1^^http://www.w3.org/2001/XMLSchema#decimal
181.1
NUMBER
+167.4^^http://www.w3.org/2001/XMLSchema#decimal
167.4
NUMBER
+7^^http://www.w3.org/2001/XMLSchema#decimal
7
NUMBER
+167.4^^http://www.w3.org/2001/XMLSchema#decimal
167.4
NUMBER
item operated
UTC date of spacecraft launch
space launch vehicle
UTC date of spacecraft launch
subclass of