Japan's H3 Returns to Flight With 6 Satellites | KeepTrack Space Brief
Japan's H3 rocket successfully launched June 11, deploying 6 smallsats to orbit after December failure. First return-to-flight for JAXA's flagship heavy-lift vehicle.
IXPE (49954)
COSPAR: 2021-121A | Alt Name: IXPE
Image
Additional Sources
Launch Details
Launch Date
December 9, 2021
Launch Site
Launch Pad
LC39A
Launch Vehicle
Orbital Elements
NORAD ID
49954
International Designator
2021-121A
Epoch
Sat, 04 Jul 2026 08:00:03 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
0.23°
Right Ascension
187.59°
Eccentricity
Calculating...
Argument of Perigee
339.51°
Period
95.34 min
Mean Motion
15.10 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
IXPE
Alternative Name
IXPE
Type
Payload
Status
Operational
Owner
MSFC
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 49954U 21121A 26185.33336806 .00014196 00000-0 78231-3 0 9997
2 49954 0.2282 187.5935 0006719 339.5101 221.0063 15.10409998 5892
Source: Celestrak
Summary
The IXPE satellite, officially designated 2021-121A with NORAD ID 49954, was launched on December 9, 2021, from the Kennedy Space Center's Launch Complex 39A using a Falcon 9 launch vehicle. The spacecraft measures 2 meters in length and has a diameter of 1.1 meters and a span of 5.2 meters. It is equipped with three co-aligned X-ray telescopes for astronomy purposes and has a dry mass of 330 kg, identical to its launch mass. Its design is characterized as Box+boom shaped, manufactured by BALL and operated by MSFC (Marshall Space Flight Center). The satellite's power system includes deployable solar arrays and batteries. IXPE's mission focuses on X-ray astronomy with an expected operational lifetime of 2-3 years.
Physical Characteristics
Length
2
Diameter
1.1
Span
5.2
Dry Mass
330
Launch Mass
330
Shape
Box+boom
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
IXPE
Purpose
Astronomy, X-ray
Mission
Astronomy, X-ray
Manufacturer
BALL
Life Expectancy
2-3 years
Bus
BCP
Configuration
BCP-300
Motor
None
Equipment
3 co-aligned X-ray telescopes
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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