C-Band
The workhorse frequency band that quietly powers satellite communications, weather radar, and Wi-Fi around the world
ORBCOMM FM21 (25475)
COSPAR: 1998-053A | Alt Name: Orbcomm C1
Image
Additional Sources
Launch Details
Launch Date
September 23, 1998
Launch Site
ERAS
Launch Pad
RW04/22
Launch Vehicle
Pegasus XL/HAPS
Orbital Elements
NORAD ID
25475
International Designator
1998-053A
Epoch
Sat, 04 Jul 2026 05:57:53 GMT
Apogee
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Perigee
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Inclination
45.01°
Right Ascension
258.87°
Eccentricity
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Argument of Perigee
269.75°
Period
100.12 min
Mean Motion
14.38 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
ORBCOMM FM21
Alternative Name
Orbcomm C1
Type
Payload
Status
Non-operational
Owner
ORBC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 25475U 98053A 26185.24853679 .00000647 00000-0 25748-3 0 9990
2 25475 45.0075 258.8683 0002314 269.7465 90.3118 14.38210612452231
Source: Celestrak
Summary
ORBCOMM FM21, also known as Orbcomm C1, is a MicroStar configuration satellite manufactured by OSCG for the purpose of communication M2M/IoT. Launched on September 23, 1998, from ERAS using the Pegasus XL/HAPS launch vehicle, it has dimensions of 0.2 meters in length and 1 meter in diameter with a span of 4.3 meters. The satellite weighs 42 kg at launch and dry mass remains the same. It is powered by two deployable solar arrays and batteries and equipped with an Orbcomm payload for its mission. The satellite's shape consists of a cylinder plus two panels and antennas, and it has a radar cross-section (RCS) value of 0.6898. ORBCOMM FM21 was launched into space by the owner ORBC and operated for approximately four years as part of its lifetime expectation.
Physical Characteristics
Length
0.2
Diameter
1
Span
4.3
Dry Mass
42
Launch Mass
42
Shape
Cyl + 2 Pan + Ant
Radar Cross Section
0.6898
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Orbcomm FM21
Purpose
Communication M2M/IoT
Mission
Communication M2M/IoT
Manufacturer
OSCG
Life Expectancy
4 years
Bus
Microstar
Configuration
MicroStar
Motor
?
Equipment
Orbcomm payload
Power System
2 deployable solar arrays, 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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