By guiding a space capsule safely back home on Jan 22, 2007, Indian space scientists have propelled our nation into a special club of three countries that can launch as well as recover spacecraft. It’s time to rise and applaud.
Scientists working on the Space Capsule Recovery Experiment (SRE) Module (Picture source: ISRO)
With the successful recovery of a space capsuleon January 22, 2007 by scientists of Indian Space Research Organisation (ISRO) and allied organisations, January 2007 would go down in history as the month in which Indian space science had taken a major leap towards indigenously developing a space program that has not only perfected the art of launching satellites but also recovering them after the completion of their task in space.
The Space Capsule Recovery Experiment (SRE-1) is an Indian experimental spacecraft which was launched from Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota on January 10, 2007 by ISRO. The launch was conducted using the Polar Satellite Launch Vehicle (PSLV C7) rocket, along with three other satellites.
Since its launch, SRE-1 was going round the earth in a circular polar orbit at an altitude of 637 km.
In preparation for its re-entry, SRE-1 was put into an elliptical orbit with a perigee (nearest point to earth) of 485 km and an apogee (farthest point to earth) of 639 km by issuing commands from the Spacecraft Control Centre (SCC) of ISTRAC at Bangalore on January 19, 2007. The critical de-boost operations were executed from SCC, Bangalore supported by a network of ground stations at Bangalore, Lucknow, Mauritius, Sriharikota, Biak in Indonesia, Saskatoon in Canada, Svalbard in Norway besides shipborne and airborne terminals.
It remained in orbit for 12 days before re-entering the Earth’s atmosphere and splashing down into the Bay of Bengal on January 22.
During its 12-day stay in orbit, the following two experiments on board SRE 1 were successfully conducted under microgravity conditions.
One of the experiments was related to the study of metal melting and crystallization under microgravity conditions.
This experiment, jointly designed by the Indian Institute of Science, Bangalore and Vikram Sarabhai Space Centre, Thiruvananthapuram, was performed in an isothermal heating furnace.
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Space Capsule Recovery Experiment (SRE-1): Mission Overview
The SRE 1 was designed to primarily:
- Demonstrate the capability to recover an orbiting space capsule, and the technology of an orbiting platform for performing experiments in microgravity conditions
- Test reusable Thermal Protection System, navigation, guidance and control, hypersonic aero-thermodynamics, management of communication blackout, deceleration and flotation system and recovery operations
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The second experiment, is jointly designed by National Metallurgical Laboratory, Jamshedpur and ISRO Satellite Centre Bangalore, was intended to study the synthesis of nano-crystals under microgravity conditions.This was an experiment in designing biomaterials that better replicate natural biological products. The experimental results will be analyzed in due course by the principal scientific investigators of the two experiments.
The de-orbiting operation (the process of bringing the capsule out of the orbit in which it was moving) was initiated at 9 am on January 22, when an onboard rocket motor was fired to slow down the speed of the capsule that was orbiting the Earth at 8 km per second. At 9.17 am, the capsule was reoriented for its re-entry into the atmosphere. It slipped into the atmosphere at 9.37 am at a speed of 8 km per second, protected from intense heat by the silica tiles on its outer surface.
The first set of parachutes opened at 5 km above sea level, and the main parachute at 2 km, allowing the capsule to slow down and strike the water at 12 metres per second. The flotation system, which was immediately triggered, kept the capsule floating. Recovery operations were supported and carried out by the Indian Coast Guard and Indian Navy using ships, aircraft and helicopters.
While it has to be noted here that USA and Russia had developed spacecraft re-entry and recovery capabilities many decades ago and China too is familiar with re-entry and has sent astronauts into space in a Chinese-made spacecraft, mastering a technology on one’s own has its own value. Add to that the fact that it still is a very small club.
Throughout the 46 minutes, telemetry signals from the capsule told ISRO scientists that all was going well. With each milestone, the engineers in the spacecraft control center clapped and cheered. And why not; the successful launch, in-orbit operation of the on board experiments and reentry and recovery of SRE-1 has demonstrated India’s capability in important technologies like aero-thermo structures, deceleration and flotation systems, navigation, guidance and control. SRE-1 is an important beginning for providing a low cost platform for micro-gravity experiments in space science and technology and return specimen from space.
“Through this capsule, we’re hoping to show the world a novel, inexpensive platform for micro-gravity science experiments,” said Kamanio Chattopadhyay, chairman of materials engineering at the Indian Institute of Science in Bangalore, when asked about the success. “Until now, micro-gravity experiments have been done on the space station or on the US space shuttle — and both are expensive,” he said. “A capsule with science experiments can routinely piggyback on large satellites,”
It’s time to put our hands together for Indian space scientists.
