ALOS-3

Advanced Land Observing Satellite 3 (ALOS-3), also called Daichi 3, was a 3-ton Japanese satellite launched on March 7 2023 which failed to reach orbit. It was to succeed the optical sensor PRISM (Panchromatic Remote-sensing Instruments for Stereo Mapping) carried on the ALOS satellite, which operated from 2006 to 2011. The ALOS-2 satellite and the ALOS-4 satellite carry synthetic-aperture radar.

Advanced Land Observing Satellite 3

Names	Daichi 3
Mission type	Remote sensing
Operator	JAXA
Website	www.jaxa.jp/projects/sat/alos3/index_j.html
Mission duration	13 minutes and 55 seconds
Spacecraft properties
Manufacturer	Mitsubishi Electric
Start of mission
Launch date	7 March 2023 1:38:15 UTC [1]
Rocket	H3-22S
Launch site	Tanegashima LP2
Contractor	Mitsubishi Heavy Industries
End of mission
Disposal	Destroyed via FTS
Last contact	March 7 2023 1:55 approximately
Decay date	March 7 2023
Orbital parameters
Reference system	Geocentric
Regime	Sun-synchronous
Instruments
OPS: OPtical Sensor IRS: InfraRed Sensor[2]
← ALOS-2 ALOS-4 →

The satellite was launched as the payload on the first launch of the H3 rocket in March 2023. A failure of the second stage engine to ignite led to the rocket along with its payload ALOS-3 being destroyed by use of Flight Termination System (FTS) to prevent risk of falling debris.

Spacecraft details

ALOS-3 had a mass of 3 tonnes, and 7 reaction wheels.^[3]

Launch

ALOS-3 launched from Tanegashima, Japan by a H3 rocket on 7 March 2023.^[1] Initially the launch was scheduled for 17 February but was aborted seconds before liftoff.^[4]

Timeline

MET	Time		Date(UTC)	Event
	JST	UTC
X-22:00:00	12:37:55	03:37:55	6 March 2023	1st Go/No-Go Decision
X-18:00:00	16:37:55	07:37:55		Airframe movement (VAB > LP2)
X-12:00:00	22:37:55	14:37:55		2nd Go/No-Go Decision
X-00:57:00	09:40:55	00:40:55	7 March 2023	3rd Go/No-Go Decision
X-00:10:00	10:27:55	01:27:55		Final Go/No-Go Decision
X-00:08:00	10:29:55	01:29:55		Start of Countdown
X-00:07:00	10:30:55	01:30:55		Safety System ready
X-00:07:00	10:30:55	01:30:55		Completion of Firing System Preparation
X-00:05:00	10:32:55	01:32:55		Satellite System ready
X-00:04:00	10:33:55	01:33:55		Automatic Countdown Sequence Start
X-00:04:00	10:33:55	01:33:55		Start of Pressurization of each tank
X-00:02:50	10:35:05	01:35:05		Power Switching (External to Internal)
X-00:00:55	10:37:00	01:37:00		Completion of each tank Pressurization
X-00:00:53	10:37:02	01:37:02		Frame deflector operation
X-00:00:35	10:37:20	01:37:20		Water Curtain operation
X-00:00:18	10:37:37	01:37:37		Flight mode on
X-00:00:15	10:37:40	01:37:40		Single-Stage Thermal battery activation
X-00:00:15	10:37:40	01:37:40		All System are ready
X-00:00:12.	10:37:43.	01:37:43		Pyrotechnic Torch Ignition
X-00:00:06	10:37:49	01:37:49		LE-9 Engine Start
X+00:00:00	10:37:55	01:37:55		SRB-3 Engine Start & Liftoff
X+00:01:06	10:39:01	01:39:01		Max Q
X+00:01:56	10:39:51	01:39:51		SRB-3 Jettision
X+00:03:32	10:41:27	01:41:27		Satellite Fairing Separation
X+00:04:56	10:42:51	01:42:51		Main Engine Cutoff (MECO)
X+00:05:04	10:42:59	01:42:59		1st and 2nd Stage Separation
X+00:13:55	10:51:50	01:51:50		Flight Interruption

Mission and sensors

If it had been successfully launched, ALOS-3 would have been an Earth observation satellite and was to be used to monitor natural disasters as well as for cartography.^[3] ALOS-3 carried OPS (OPtical Sensor), a multi-band optical camera which is an upgrade from the PRISM sensor.^[2] OPS was capable of observing a 70-kilometer (43 mi) wide strip of land on Earth.^[5] In addition to the RGB and infrared band covered by the predecessor ALOS satellite, ALOS-3 has two additional bandwidths: coastal and red edge. Coastal allows observation underwater up to a depth of 30m, while red edge was to be used to monitor vegetation growth.^[5]

See also

• Spaceflight portal

• 2023 in spaceflight