RISAT-2 and ANUSAT

In its fifteenth mission carried out from Satish Dhawan Space Centre SHAR (SDSC SHAR), Sriharikota today (April 20, 2009), ISRO's Polar Satellite Launch Vehicle (PSLV-C12) successfully placed two satellites - RISAT-2 and ANUSAT - in the desired orbit.

RISAT-2 is a Radar Imaging Satellite with the capability to take images of the earth during day and night as well as cloudy conditions.

At the time of launch, RISAT-2 weighed about 300 kg and was realised by ISRO in association with Israel Aerospace Industries. The satellite was placed in an orbit of 550 km height with an inclination of 41 deg to the equator and an orbital period of about 90 minutes. This satellite will enhance ISRO's capability for earth observation, especially during floods, cyclones, landslides and in disaster management in a more effective way.

The 44 metre tall PSLV-C12 weighing 230 ton was launched from the Second Launch Pad (SLP) at SDSC SHAR in the Core Alone configuration without the use of six solid strap-ons. In this mission, in addition to RISAT-2, PSLV also carried A 40 kg micro satellite named ANUSAT, built by Anna University, Chennai. ANUSAT is the first experimental communication satellite built by an Indian University under the over all guidance of ISRO and will demonstrate the technologies related to message store and forward operations.

Integration of PSLV for the C12 flight commenced at the Second Launch Pad in SDSC, SHAR on February 26, 2009. Following this, the first, second, third and fourth stages of the vehicle along with the satellites were fully integrated. After a 48 hour countdown, the vehicle and the satellites successfully underwent various levels of functional checks at the launch centre.

In this flight, PSLV carried the indigenously developed Advanced Mission Computers and Advanced Telemetry System, which guided the vehicle from lift-off till the injection of the two satellites in the desired orbit.

PSLV-C12 lifted off from the Second Launch Pad at 6:45 am IST (0115 UT) today with the ignition of its first stage. The important flight events included the separation of the first stage, ignition of the second stage, separation of the payload fairing at about 115 km altitude after the vehicle had cleared the dense atmosphere, second stage separation, third stage ignition, third stage separation, fourth stage ignition and fourth stage cut-off.

The main payload, RISAT-2, was the first satellite to be separated in orbit at 1100 seconds after lift-off at an altitude of 550 km. About 60 seconds later, ANUSAT was separated.

With this successful launch, the versatility and the reliability of PSLV has been proved again underscoring its importance as the workhorse launch vehicle of India. Today's launch was the fourteenth consecutive success for PSLV. In these launches, PSLV has placed a total of sixteen Indian satellites and sixteen foreign satellites into Polar, Geosynchronous Transfer and Low Earth Orbits. It may be recalled that during its previous mission on October 22, 2008, PSLV had successfully launched Chandrayaan-1 spacecraft, which is now exploring the moon from lunar orbit.