Space Brief 27 Jul 2025
Busy activities in space: SpaceX's series of Starlink launches dominate the week, while Vega C successfully deploys Earth science satellites.
MOMO-1B (MOS-1B) (20478)
COSPAR: 1990-013A | Alt Name: Momo-1B
Image
Additional Sources
Launch Details
Launch Date
February 7, 1990
Launch Site
TANSC
Launch Pad
N
Launch Vehicle
H-1
Orbital Elements
NORAD ID
20478
International Designator
1990-013A
Epoch
Sat, 04 Jul 2026 02:45:38 GMT
Apogee
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Perigee
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Inclination
99.22°
Right Ascension
246.25°
Eccentricity
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Argument of Perigee
133.52°
Period
103.15 min
Mean Motion
13.96 rev/day
Latitude
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Longitude
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Altitude
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Velocity
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Polar Plot
3D Visualization
Basic Satellite Info
Name
MOMO-1B (MOS-1B)
Alternative Name
Momo-1B
Type
Payload
Status
Non-operational
Owner
NASDA
Country
Japan
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 20478U 90013A 26185.11502536 .00000087 00000-0 96567-4 0 9991
2 20478 99.2182 246.2467 0006218 133.5183 226.6496 13.96076185774397
Source: Celestrak
Summary
MOMO-1B (MOS-1B), also known as Momo-1B, is an Earth Observation satellite launched on February 7, 1990, from the Tanegashima Space Center in Japan using the H-1 launch vehicle. The spacecraft has a configuration of Box + Pan with dimensions: length of 2.4 meters, diameter of 1.3 meters, and span of 6.3 meters. It was manufactured by NEC for NASDA (National Space Development Agency) and carries equipment including MESSR, VTIR, MSR for its mission. The satellite has a dry mass and launch mass both recorded at 740 kg. Power is supplied through deployable solar arrays and batteries. The RCS (Reaction Control System) area is 2.9616 square meters.
Physical Characteristics
Length
2.4
Diameter
1.3
Span
6.3
Dry Mass
740
Launch Mass
740
Shape
Box + Pan
Radar Cross Section
2.9616
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
MOS-1b
Purpose
Earth Observation
Mission
Earth Observation
Manufacturer
NEC
Life Expectancy
Unknown
Bus
MOS
Configuration
Unknown
Motor
Unknown
Equipment
MESSR, VTIR, MSR
Power System
Deployable solar array, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
Map
Next Pass
Azimuth Elevation Time (Local)
Start Azimuth
Max Elevation
Stop Azimuth
Time Until
Pass Duration
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