The Day America Pioneered Polar Orbits
Sixty-six years ago, a Thor-Agena rocket thundered into the California sky carrying Discoverer 1, the first satellite attempt at polar orbit and the secret vanguard of Americas space reconnaissance program
STARLINK-2639 (48436)
COSPAR: 2021-040J | Alt Name: Starlink 2639
Image
Additional Sources
Launch Details
Launch Date
May 9, 2021
Launch Site
Launch Pad
LC40
Launch Vehicle
Orbital Elements
NORAD ID
48436
International Designator
2021-040J
Epoch
Sat, 04 Jul 2026 04:13:57 GMT
Apogee
Calculating...
Perigee
Calculating...
Inclination
53.16°
Right Ascension
356.18°
Eccentricity
Calculating...
Argument of Perigee
93.13°
Period
94.01 min
Mean Motion
15.32 rev/day
Latitude
Calculating...
Longitude
Calculating...
Altitude
Calculating...
Velocity
Calculating...
Polar Plot
3D Visualization
Basic Satellite Info
Name
STARLINK-2639
Alternative Name
Starlink 2639
Type
Payload
Status
Operational
Owner
SPXS
Country
United States
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 48436U 21040J 26185.17636494 .00000410 00000-0 24961-4 0 9995
2 48436 53.1603 356.1813 0001083 93.1280 266.9845 15.31713819284527
Source: Celestrak
Summary
The STARLINK-2639 satellite, also known as Starlink 2639, is operated by SPXS and was launched on May 9, 2021, from the Air Force Eastern Test Range Launch Complex 40 using a Falcon 9 launch vehicle. It has dimensions of 0.2 meters in length, 2.8 meters in diameter, and spans 9 meters with solar arrays and batteries providing power. The satellite weighs 260 kilograms at launch and 248 kilograms dry mass. Equipped with Ku/Ka-band payload (all) and optical inter-satellite links (a few prototypes), it is designed for communication purposes. Its propulsion system consists of Krypton ion thrusters, and its shape can be described as box-shaped with a pan configuration.
Starlink is a satellite constellation developed by SpaceX with the aim of providing global broadband internet coverage. Thousands of small satellites are deployed in low Earth orbit (LEO), enabling high-speed internet access even in remote areas. However, the rapid increase in satellites raises concerns about space debris and the potential for collisions, which can lead to further debris creation and endanger other spacecraft. Additionally, the sheer number of Starlink satellites can affect astronomical observations by increasing light pollution. Proper deorbiting plans and international coordination are essential to mitigate these challenges and ensure long-term sustainability in space.
Starlink is a satellite constellation developed by SpaceX with the aim of providing global broadband internet coverage. Thousands of small satellites are deployed in low Earth orbit (LEO), enabling high-speed internet access even in remote areas. However, the rapid increase in satellites raises concerns about space debris and the potential for collisions, which can lead to further debris creation and endanger other spacecraft. Additionally, the sheer number of Starlink satellites can affect astronomical observations by increasing light pollution. Proper deorbiting plans and international coordination are essential to mitigate these challenges and ensure long-term sustainability in space.
Physical Characteristics
Length
0.2
Diameter
2.8
Span
9
Dry Mass
248
Launch Mass
260
Shape
Box + pan
Radar Cross Section
Unknown
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Starlink V1.0-L27-09
Purpose
Communication
Mission
Communication
Manufacturer
SPXS
Life Expectancy
Unknown
Bus
Starlink
Configuration
Unknown
Motor
Krypton ion thrusters
Equipment
Ku/Ka-band payload (all), optical inter-satellite links (a few prototypes)
Power System
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
Satellite Articles
View All Posts »Learn more about satellites and other related topics.
Space Brief 30 Nov 2024
Today's highlights include SpaceX's dual satellite launches, a new Space Force contract with Raytheon, and Astroscale's upcoming OneWeb mission.
X Report 12 Dec 2024
SpaceX progresses with Starship developments and sets sights on NASA's upcoming 3D sky-mapping satellite launch.
The Day America Shot Down Its Own Spy Satellite
Seventeen years ago, a Navy cruiser in the Pacific fired a missile at a tumbling reconnaissance satellite that had failed within hours of reaching orbit - officially to prevent toxic fuel from reaching the ground, unofficially to prove something far more significant to China and the world
Shimizu's Luna Ring - The Plan to Wrap the Moon in Solar Panels
A 220-year-old Japanese construction company wants to build an 11,000-kilometer belt of solar cells around the lunar equator and beam the power back to Earth. The physics checks out. Everything else is another story.
The Day Superpowers Shared Space
Exactly 52 years ago today, the Soviet Union launched Soyuz 13 - a scientific mission that marked the first time American astronauts and Soviet cosmonauts orbited Earth simultaneously. Armed with a revolutionary ultraviolet telescope, Pyotr Klimuk and Valentin Lebedev would discover elements never before seen in distant nebulae.
Space Brief 18 Nov 2025
Key updates on strategic military shifts, technological advancements, and a critical replacement mission for Chinese astronauts highlight today's space news.
Space Brief 10 Jun 2025
Today's brief covers increased Space Force funding, a renewed focus on nuclear power in space, a proposed US missile defense system, new defense budget revelations, and NATO's call for increased air defenses.