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GP-B (28230)
COSPAR: 2004-014A | Alt Name: Gravity Probe B
Image
Additional Sources
Launch Details
Launch Date
April 20, 2004
Launch Site
AFWTR
Launch Pad
SLC2W
Launch Vehicle
Delta 7920-10C
Orbital Elements
NORAD ID
28230
International Designator
2004-014A
Epoch
Sat, 04 Jul 2026 02:21:25 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
89.85°
Right Ascension
49.88°
Eccentricity
Calculating...
Argument of Perigee
101.94°
Period
97.08 min
Mean Motion
14.83 rev/day
Latitude
Calculating...
Longitude
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Altitude
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Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
GP-B
Alternative Name
Gravity Probe B
Type
Payload
Status
Non-operational
Owner
MSFC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 28230U 04014A 26185.09821402 .00000805 00000-0 96343-4 0 9994
2 28230 89.8487 49.8770 0002258 101.9435 258.2043 14.83302347654853
Source: Celestrak
Summary
Gravity Probe B (GP-B) is a US satellite launched on April 20, 2004, from Vandenberg Air Force Base's Space Launch Complex 2W using a Delta 7920-10C launch vehicle. The spacecraft measures 6.4 meters in length and 2.6 meters in diameter with a span of 6.4 meters. It has a dry mass of 2805 kg and a launch mass of 3145 kg. Equipped with four gyroscopes, a quartz telescope, GPS receiver, and retroreflector array, GP-B was designed for fundamental physics research related to the principle of relativity. The satellite uses four deployable fixed solar arrays and batteries for power supply. It has an elliptical shape with antennas and four panels and is operated by MSFC (Marshall Space Flight Center).
Physical Characteristics
Length
6.4
Diameter
2.6
Span
6.4
Dry Mass
2805
Launch Mass
3145
Shape
Ell + Ant + 4 Pan
Radar Cross Section
10.178
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
GP-B
Purpose
Fundamental Physics (Principle of relativity)
Mission
Fundamental Physics (Principle of relativity)
Manufacturer
LMMS/STAN
Life Expectancy
Unknown
Bus
Unknown
Configuration
Unknown
Motor
Unknown
Equipment
Four gyroscopes, Quartz telescope, GPS receiver, Retroreflector array
Power System
4 deployable fixed 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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