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HELIOS 1B (25977)
COSPAR: 1999-064A | Alt Name: Helios 1B
Image
Additional Sources
Launch Details
Launch Date
December 3, 1999
Launch Site
FRGUI
Launch Pad
ELA2
Launch Vehicle
Ariane 40
Orbital Elements
NORAD ID
25977
International Designator
1999-064A
Epoch
Sat, 04 Jul 2026 04:35:34 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
98.16°
Right Ascension
90.82°
Eccentricity
Calculating...
Argument of Perigee
68.22°
Period
96.77 min
Mean Motion
14.88 rev/day
Latitude
Calculating...
Longitude
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Altitude
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Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
HELIOS 1B
Alternative Name
Helios 1B
Type
Payload
Status
Non-operational
Owner
CNES/DGA
Country
France
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 25977U 99064A 26185.19136691 .00001648 00000-0 18568-3 0 9996
2 25977 98.1597 90.8223 0002366 68.2201 291.9266 14.88053365702581
Source: Celestrak
Summary
The HELIOS 1B satellite, also known as Spot 4, is an electro-optical reconnaissance satellite configured as a SPOT Mk.2 and operated by CNES/DGA. Launched on December 3, 1999, from ELA2 at the Guiana Space Center using an Ariane 40 launch vehicle, this French-owned spacecraft measures 3.5 meters in length with a diameter of 2 meters and a span of 4 meters. It has a dry mass of 2500 kg and was launched with a total mass of 2544 kg. HELIOS 1B is equipped with deployable solar arrays and batteries for power, and it features a Spot AOCS motor system for orientation control. The satellite's primary purpose is electro-optical reconnaissance, and its shape is described as a box with a panoramic component. With an expected lifetime of five years, HELIOS 1B was manufactured by MMST and has an RCS (radar cross-section) value of 6.7564 square meters.
Physical Characteristics
Length
3.5
Diameter
2
Span
4
Dry Mass
2500
Launch Mass
2544
Shape
Box + Pan
Radar Cross Section
6.7564
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Helios 1B
Purpose
Reconnaissance, electro-optical
Mission
Reconnaissance, electro-optical
Manufacturer
MMST
Life Expectancy
5 years
Bus
Spot 4
Configuration
SPOT Mk.2
Motor
Spot AOCS
Equipment
?
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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