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IRS-1C
The fourth in the IRS series, IRS - 1C was launched from Baikanur cosmodrome, Kazakhstan on May 19, 1995. It operates in a near polar, sun- synchronous orbit at an altitude of 817km. Its local equatorial crossing time is 10:30 A.M in the descending node. The satellite payload consists of three sensors, namely Panchromatic camera (PAN), Linear Imaging and Self-Scanning Sensor (LISS - III) and Wide Field Sensor (WiFS).
The PAN camera provides data with a spatial resolution of 5.8m and a ground swath of 70 km at nadir view. This camera can be steered up to +/- 26 degrees, which can be used to acquire stereo pairs and this also improves the revisit capability to 5 days.
LISS - III camera provides multi-spectral data in 4 bands. The spatial resolution for visible (two bands) and near infrared (one band) is 23.5m with a ground swath of 141 km. The fourth band (short wave infrared band) has a spatial resolution of 70.5m with a ground swath of 148 km. The repetivity of LISS - III is 24 days.
WiFS camera collects data in two spectral bands with a spatial resolution of 188m and a ground swath of 810 km. By virtue of its wide swath there is huge side lap between adjacent paths. A repetivity of 3 days can be achieved by suitably combining paths.
The satellite is equipped with an On Board Tape Recorder (OBTR) with a capacity of 62 Gb, for collecting data outside the visibility region of any ground station. The OBTR was capable of storing data collected for 24 minutes. The OBTR was functional during 1995-1998.
Orbit |
Polar, Sun synchronous |
Altitude |
817 Km |
Inclination |
98.69 deg |
Local Time |
10:30 A.M |
Repetivity |
24 Days |
Orbits/cycle |
341 |
Period |
101.35 min |
Sensors |
PAN, LISS-III, WiFS |
PANCHROMATIC Sensor Characteristics
Resolution |
5.8m |
Swath |
70 km (3 x 23.33 km) |
Revisit |
5 days by tilting the camera |
Spectral Bands |
0.50 – 0.75 Microns |
Quantization (Bits) |
6 |
Steerability |
+/- 26 degrees |
LISS-III Sensor Characteristics
Resolution |
23.5 m (Visible and near IR region)
70.5 m (Shortwave IR region ) |
Swath |
141 km (Visible and near IR region)
148 km (Shortwave IR region ) |
Revisit |
24 days |
Spectral Bands |
0.52 - 0.59 microns (B2)
0.62 - 0.68 microns (B3)
0.77 - 0.86 microns (B4)
1.55 - 1.70 microns (B5) |
Quantization |
7 bits |
WiFS Sensor Characteristics
Resolution |
188 m |
Swath |
810 km |
Revisit |
3 days |
Spectral Bands |
0.62 - 0.68 microns (Visible)
0.77 - 0.86 microns (near infra-red) |
Quantization |
7 bits |
Products
Sensor |
Resolution(m) & No. of Bands
|
Coverage
Km x Km |
Data Products |
Type |
Media |
Scale of Photo products |
PAN
|
5.8
( one)
|
70x70 -90
23x23
23x23
14x14
9x9 |
Full Scenes with SAT
Sub-scenes with SAT
Sub-scenes stereo pairs
Geocoded (7 1/2'x7 1/2')
Geocoded (5' x 5') |
Digital, B&W
Digital,B/W
Digital
Digital, B&W Digital, B/W |
1:125,000
1: 50,000
-
1: 25,000
1: 12,500 |
LISS-III
|
23.5
2(V),1 (NIR))
70
1(SWIR) |
141x141
70x70
28x28 |
Full Scenes with SAT
Quadrants
Geocoded (15'x15')
(map & floating) |
Digital, FCC
Digital, FCC
Digital, FCC |
1:250, 000
1:125, 000
1:50, 000 |
WIFS
|
188
two (V, NIR)
|
810x810
|
Full Scenes with SAT
|
Digital, FCC (Bands 3,3,4)
|
1.2 Million
|
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