X Report 15 Nov 2024
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UFO 8 (USA 138) (25258)
COSPAR: 1998-016A | Alt Name: UHF F/O F8
Image
Additional Sources
Launch Details
Launch Date
March 16, 1998
Launch Site
Launch Pad
SLC36A
Launch Vehicle
Atlas II
Orbital Elements
NORAD ID
25258
International Designator
1998-016A
Epoch
Fri, 03 Jul 2026 21:30:06 GMT
Apogee
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Perigee
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Inclination
11.15°
Right Ascension
22.65°
Eccentricity
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Argument of Perigee
242.58°
Period
1436.15 min
Mean Motion
1.00 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
UFO 8 (USA 138)
Alternative Name
UHF F/O F8
Type
Payload
Status
Non-operational
Owner
PMW146
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 25258U 98016A 26184.89591127 -.00000182 00000-0 00000-0 0 9991
2 25258 11.1504 22.6522 0003524 242.5796 132.3639 1.00267836104032
Source: Celestrak
Summary
The satellite UFO 8 (USA 138), also known as UHF F/O F8, is a communication spacecraft manufactured by HSES and owned by PMW146. Launched on March 16, 1998, from the AFE launch site at SLC36A using an Atlas II vehicle, this satellite has a configuration of HS-601 with dimensions including a length of 6 meters, diameter of 3.3 meters, and span of 26.2 meters. It carries UHF, EHF, and GBS (Ka-Band) transponders for its communication mission and is equipped with two deployable solar arrays and batteries for power generation. With a launch mass of 3200 kg and a dry mass of 1350 kg, the satellite's shape consists of a box with two panels and has an RCS value of 14.1421. The satellite was designed to operate for a lifetime of approximately 14 years.
Physical Characteristics
Length
6
Diameter
3.3
Span
26.2
Dry Mass
1350
Launch Mass
3200
Shape
Box + 2 Pan
Radar Cross Section
14.1421
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
UFO F8
Purpose
Communication
Mission
Communication
Manufacturer
HSES
Life Expectancy
14 years
Bus
HS-601
Configuration
HS-601
Motor
R-4D-11-300
Equipment
UHF, EHF, GBS (Ka-Band) transponders
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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