Rohini Satellite 1

Rohini Satellite 1 or RS-1 is the first satellite successfully launched by India using indigenously developed rockets. After the launch on 18 July 1980 by a SLV rocket, India became the 7th country to have rocket launching capability.

Rohini 1

Stamp issued depicting the launch of SLV-3 and Rohini satellite
Mission type	Earth observation
Operator	ISRO
COSPAR ID	1980-062A
Website	https://www.isro.gov.in/
Mission duration	1.2 years (operational), remained in orbit for 20 months
Spacecraft properties
Spacecraft	RS-1
Manufacturer	Indian Space Research Organisation
Launch mass	35 kg (77 lb)
Dimensions	0.7m long, 0.6m diameter
Power	16 W
Start of mission
Launch date	18 July 1980, 8:04 AM IST (2:34 AM GST)
Rocket	Satellite Launch Vehicle, SLV-3
Launch site	Satish Dhawan Space Centre
Contractor	Indian Space Research Organisation
Entered service	July 1980
End of mission
Disposal	atmospheric re-entry
Deactivated	20 May 1981
Orbital parameters
Reference system	Geocentric orbit
Regime	Low Earth orbit
Perigee altitude	305 km (190 mi)
Apogee altitude	919 km (571 mi)
Inclination	44.7°
Period	96.90 minutes
Instruments
Digital sun sensor, Magnetometer and temperature sensors
Rohini ← RTP RS-D1 →

The satellite was spin-stabilised and provided data regarding the fourth stage of SLV rocket.^[1]

Launch

Launched 8:04 AM IST from Satish Dhawan Space Centre, it was the first successful orbital launch from the centre. It achieved orbit 305 km × 919 km (190 mi × 571 mi) with an inclination of 44.7°, 8 minutes after the launch. It was launched after the failure of the first two SLV launches. The SLV rocket consisted of 25 km wiring, containing a million connections. 44 major systems and 250 subsystems were in the rocket. Individual components numbered about 100,000, and included almost 40,000 fasteners.^[2] At the time of launch, it weighed 17 tonnes and had a height of 22 meters.

The vehicle's trajectory was monitored by four long and medium range radars. Long-range Interferometer and optical line theodolites also aided in tracking. Four computer systems received trajectory information from the tracking sources and processed the data simultaneously. They displayed the vehicle's path on monitors in the range safety room of the control centre. Sriharikota, Car Nicobar, Trivandrum and Ahmedabad centres joined in to provide tracking and telemetry support for the satellite. Mediapersons were not allowed to the space centre during the launch. Many viewed the launch and the 5 km high white smoke from afar.^[3]

Design

The satellite had a weight of 35 kg, and was spin stabilized. It carried instruments such as digital Sun sensor, Magnetometer and temperature sensors atop a structure made out of Aluminium Alloy. It carried solar panels to produce 16W of electricity. It used a VHF band for communications.^[4] It provided data on the fourth stage of SLV. The satellite had mission life of 1.2 years and an orbital life of 20 months. It was planned to have a lifespan of 100 days.