Ikonos

From Wikipedia, the free encyclopedia
  (Redirected from IKONOS)
Jump to: navigation, search
Ikonos-2
Mission type Earth observation
Operator DigitalGlobe
Formerly GeoEye, Space Imaging
COSPAR ID 1999-051A
SATCAT № 25919
Mission duration Final: 15 years, 6 months, 6 days
Spacecraft properties
Bus LM-900[1]
Manufacturer Lockheed Martin Space Systems
Launch mass 817 kg (1,801 lb)[1]
Dimensions 1.83 × 1.57 m (6.0 × 5.2 ft)[1]
Power 1,500 W[1]
Start of mission
Launch date 24 September 1999, 18:22 (1999-09-24UTC18:22) UTC[2]
Rocket Athena II, LM-007
Launch site Vandenberg AFB SLC-6
Contractor Lockheed Martin
Entered service December 1999[1]
End of mission
Disposal Decommissioned
Deactivated 31 March 2015 (2015-04-01)[3]
Orbital parameters
Reference system Geocentric
Regime Low Earth
Eccentricity 0.00028
Perigee 678 km (421 mi)
Apogee 682 km (424 mi)
Inclination 98.2°
Period 98.4 minutes
Epoch 24 September 1999, 18:22 UTC[2]
Main telescope
Type Cassegrain[1]
Diameter 70 cm (28 in)[1]
Focal length 10 m (33 ft)[1]
Wavelengths Panchromatic: 450-900 nm[1]
Multispectral: 450-860 nm[1]
Resolution Panchromatic: 0.82–1 m (32–39 in)[1]
Multispectral: 3.2–4 m (130–160 in)[1]

IKONOS is a commercial Earth observation satellite, and was the first to collect publicly available high-resolution imagery at 1- and 4-meter resolution. It offers multispectral (MS) and panchromatic (PAN) imagery. The IKONOS launch was called “one of the most significant developments in the history of the space age”.[4] IKONOS imagery began being sold on 1 January 2000.

It derived its name from the Greek term eikōn for image.[5]

History[edit]

IKONOS was originated under the Lockheed Corporation as the Commercial Remote Sensing System (CRSS) satellite. In April 1994 Lockheed was granted one of the first licenses from the U.S. Department of Commerce for commercial satellite high-resolution imagery.[6] On 25 October 1995 partner company Space Imaging received a license from the Federal Communications Commission (FCC) to transmit telemetry from the satellite in the eight-gigahertz Earth Exploration Satellite Services band.[7] Prior to launch, Space Imaging changed the name of the satellite system to IKONOS. The name comes from the Greek word for "image".[5]

Two satellites were originally planned for operation. IKONOS-1 was launched on 27 April 1999 at 18:22 UTC from Vandenberg Air Force Base SLC-6,[8][9] but Athena II rocket's payload fairing did not separate due to an electrical malfunction, resulting in the satellite failing to reach orbit and falling into the atmosphere over the South Pacific Ocean.[10]

IKONOS-2 was built in parallel with and as an identical twin to IKONOS-1. Completion of its construction was projected for July 1999 with a January 2000 launch.[11] In reaction to the loss of IKONOS-1, the spacecraft was renamed IKONOS[11][12] and its processing accelerated, resulting in a launch on 24 September 1999 at 18:22 UTC, also from Vandenberg aboard an Athena II rocket.[2] IKONOS has a mass of 817 kilograms (1,800 lb) and operates in a Sun-synchronous, near-polar, circular 681 km (423 mi) orbit.[1] It has five imaging sensors, one panchromatic and four multispectral (blue, green, red, and near-infrared), and has a nadir image swath width of 11.3 km (7 mi).[13]

In December 2000, IKONOS received the "Best of What's New" Grant Award in Aviation & Space from Popular Science magazine.[14] The acquisition of Space Imaging and its assets by Orbimage was announced in September 2005 and finalized in January 2006.[15][16] The merged company was renamed GeoEye,[16] which was itself acquired by DigitalGlobe in January 2013.[17] DigitalGlobe operated IKONOS until its retirement on 31 March 2015.[3]

Specifications[edit]

Spacecraft[edit]

IKONOS is a three-axis stabilized spacecraft designed by Lockheed Martin. The design later became known as the LM900 satellite bus system. The satellite's altitude is measured by two star trackers and a sun sensor and controlled by four reaction wheels; location knowledge is provided by a GPS receiver. The design life is seven years; S/C body size=1.83 m × 1.57 m (hexagonal configuration); S/C mass = 817 kg; power = 1.5 kW provided by three solar panels.

The LM900 spacecraft is a three-axis stabilized bus that is designed to carry scientific payloads in LEOs. It provides precision pointing on an ultra stable highly agile platform. Payloads for a variety of scientific and remote sensing applications may be accommodated including laser sensors, imagers, radar sensors, electro-optical and astronomical sensors, as well as planetary sensors. The LM900 bus shares a hardware heritage with Iridium, which is the basis for the LM700 bus.

Communications[edit]

IKONOS conducts telemetry, tracking and control in the 8345.968–8346.032 MHz band (downlink) and 2025–2110 MHz band (uplink). Downlink data carrier operates in the 8025-8345 MHz band.

Optics & Detectors[edit]

IKONOS has a primary mirror aperture of 0.7 m (2.3 feet), and a folded optical focal length of 10 m (about 33 feet) using 5 mirrors.[18] The main mirror features a honeycomb design to reduce mass.[18] The detectors at the focal plane include a pan-chromatic and a multi-spectral sensor, with 13500 pixels and 3375 pixels respectively (cross-track).[18] Total instrument mass is 171 kg (377 pounds) and it uses 350 watts.[18]

Imaging capabilities[edit]

Spatial resolution[edit]

  • 0.8 m panchromatic (1-m PAN)
  • 4-meter multispectral (4-m MS)
  • 1-meter pan-sharpened (1-m PS)

Spectral Resolution

Band 1-m PAN 4-m MS & 1-m PS
1 (Blue) 0.45–0.90 µm 0.445–0.516 µm
2 (Green) * 0.506–0.595 µm
3 (Red) * 0.632–0.698 µm
4 (Near IR) * 0.757–0.853 µm

Temporal resolution[edit]

The revisit rate for IKONOS is three to five days off-nadir and 144 days for true-nadir.

Radiometric resolution[edit]

The sensor collects data with an 11-bit (0–2047) sensitivity and are delivered in an unsigned 16-bit (0–65535) data format. From time-to-time the data are rescaled down to 8-bit (0–255) to decrease file size. When this occurs much of the sensitivity of the data needed by remote sensing scientists is lost.

Swath[edit]

11 km × 11 km (single scene)

See also[edit]

Notes[edit]

  1. ^ a b c d e f g h i j k l m "Ikonos-2". eoPortal. European Space Agency. Retrieved 19 September 2016. 
  2. ^ a b c "Launch/Orbital information for Ikonos 2". National Space Science Data Center. NASA. Retrieved 19 September 2016. 
  3. ^ a b "DigitalGlobe's IKONOS Satellite Retired After 15 Years of On-Orbit Operation" (Press release). Lockheed Martin. 14 May 2015. 
  4. ^ Broad, William J. (13 October 1999). "Giant Leap for Private Industry: Spies in Space". The New York Times. Retrieved 23 January 2010. 
  5. ^ a b "Imagery Sources". GeoEye. Retrieved 21 May 2012. 
  6. ^ "Company News: Lockheed Wins License for Satellite Sensing System". The New York Times. 26 April 1994. Retrieved 3 December 2016. 
  7. ^ Turner, Linda (25 October 1995). "Space Imaging granted FCC license for private remote sensing satellite system" (Press release). Business Wire via TheFreeLibrary.com. Retrieved 3 December 2016. 
  8. ^ Mecham, Michael (3 May 1999). "Faulty Athena Shroud Ruins Ikonos 1 Launch". Aviation Week & Space Technology. Retrieved 3 December 2016. 
  9. ^ Brender, Mark; Lidov, Linda (27 April 1999). "Lockheed Martin Athena Launch of Ikonos Satellite Experienced an Anomaly" (Press release). Space Imaging via FAS.org. Retrieved 3 December 2016. 
  10. ^ Harland, David M.; Lorenz, Ralph D. (2006) [2005]. Space Systems Failures: Disasters and Rescues of Satellites, Rocket and Space Probes. Springer Science+Business Media. p. 107. ISBN 0-387-21519-0. 
  11. ^ a b "DA 01-765: Application for Modification of Space Station Authorization". Federal Communications Commission. 28 March 2001. Archived from the original on 3 December 2016. 
  12. ^ Lavers, Christopher (2013). Recent Developments in Remote Sensing for Human Disaster Management and Mitigation - Natural and Man-made 2013. Lulu.com. pp. 28–29. ISBN 978-1-291-22463-4. 
  13. ^ "IKONOS Satellite Sensor". Satellite Imaging Corporation. Retrieved 3 December 2016. 
  14. ^ "Spy Sat for the Rest of Us". Popular Science. 257 (6): 44. December 2000. 
  15. ^ Frederick, Missy (19 September 2005). "Orbimage-Space Imaging Merger Expected To Stabilize the Industry". SpaceNews. Retrieved 3 December 2016. 
  16. ^ a b Vuong, Andy (12 January 2006). "Thornton's Space Imaging Acquired". The Denver Post. Retrieved 3 December 2016. 
  17. ^ Ferster, Warren (31 January 2013). "DigitalGlobe Closes GeoEye Acquisition". SpaceNews. Retrieved 3 December 2016. 
  18. ^ a b c d Herbert J. Kramer - Observation of the earth and its environment: survey of missions and sensors (2002) - Page 286 (Google Books Link)

References[edit]

External links[edit]