LASER Instrument on Chandrayaan-1 Successfully Turned ON

November 16, 2008

Lunar Laser Ranging Instrument (LLRI), one of the 11 scientific instruments (payloads) carried by Chandrayaan-1 spacecraft, has successfully been turned ON today (November 16, 2008). The instrument was switched ON when the spacecraft was passing over western part of the moon’s visible hemisphere. Preliminary assessment of the data from LLRI by ISRO scientists indicates that the instrument’s performance is normal. LLRI sends pulses of infrared laser light towards a strip of lunar surface and detects the reflected portion of that light. With this, the instrument can very accurately measure the height of moon’s surface features. LLRI will be continuously kept ON and takes 10 measurements per second on both day and night sides of the moon. It provides topographical details of both polar and equatorial regions of the moon. Detailed analysis of the data sent by LLRI helps in understanding the internal structure of the moon as well as the way that celestial body evolved.

അഭിനന്ദനങ്ങള്‍ Indian Tricolour Placed on the Moon !! CONGRATULATIONS

November 14, 2008

In a historic event, the Indian space programme achieved a unique feat today (November 14, 2008) with the placing of Indian tricolour on the Moon’s surface on Pandit Jawaharlal Nehru’s birthday. The Indian flag was painted on the sides of Moon Impact Probe (MIP), one of the 11 payloads of Chandrayaan-1 spacecraft, that successfully hit the lunar surface today at 20:31 hrs (8:31 pm) IST. This is the first Indian built object to reach the surface of the moon. The point of MIP’s impact was near the Moon’s South Polar Region. It may be recalled that the modern Indian space programme was initiated in 1962 when Pandit Jawaharlal Nehru was the Prime Minister of India.

Weighing 34 kg at the time of its launch onboard Chandrayaan-1, the box shaped MIP carried three instruments – a video imaging system, a radar altimeter and a mass spectrometer. The video imaging system was intended to take the pictures of the moon’s surface as MIP approached it. The radar altimeter was included to measure the rate of descent of the probe to the lunar surface. Such instruments are necessary for future lunar soft landing missions. And, the mass spectrometer was for studying the extremely thin lunar atmosphere.

MIP’s 25 minute journey to the lunar surface began with its separation from Chandrayaan-1 spacecraft at 20:06 hrs (8:06 pm) IST. This was followed by a series of automatic operations that began with the firing of its spin up rockets after achieving a safe distance of separation from Chandrayaan-1. Later, the probe slowed down with the firing of its retro rocket and started its rapid descent towards the moon’s surface. Information from the its instruments was radioed to Chandrayaan-1 by MIP. The spacecraft recorded this in its onboard memory for later readout. Finally, the probe had a hard landing on the lunar surface that terminated its functioning.

Thus, India’s very first attempt to send a probe to the moon’s surface from its spacecraft orbiting the moon has been successfully concluded.

With the switching ON of two of Chandrayaan-1’s payloads – Terrain Mapping Camera (TMC) and Radiation Dose Monitor (RADOM) – on its journey to moon and with MIP’s successful impact on the lunar surface today, it is planned to switch ON and test the remaining eight payloads of the spacecraft in the coming few days.

First Lunar Orbit Reduction Manoeuvre of Chandrayaan-1 Successfully Carried Out

November 10, 2008
The first orbit reduction manoeuvre of Chandrayaan-1 spacecraft which is orbiting the moon, was successfully performed yesterday (November 9, 2008) night. As part of that manoeuvre which began at 20:03 IST, the 440 Newton liquid engine of the spacecraft was fired for about 57 seconds. With this, the nearest point of Chandrayaan-1’s orbit (periselene) from the moon’s surface was reduced from 504 km to 200 km while the farthest point (aposelene) remained unchanged at 7,502 km. In this elliptical orbit, Chandrayaan-1 takes about ten and a half hours to circle the moon once.

Chandrayaan-1 Successfully Enters Lunar Orbit

November 8, 2008

Chandrayaan-1, India’s first unmanned spacecraft mission to moon, entered lunar orbit today (November 8, 2008). This is the first time that an Indian built spacecraft has broken away from the Earth’s gravitational field and reached the moon. This historic event occurred following the firing of Chandrayaan-1 spacecraft’s liquid engine at 16:51 IST for a duration of 817 seconds. The highly complex ‘lunar orbit insertion manoeuvre’ was performed from Chandrayaan-1 Spacecraft Control Centre of ISRO Telemetry, Tracking and Command Network at Bangalore.

Indian Deep Space Network (IDSN) at Byalalu supported the crucial task of transmitting commands and continuously monitoring this vital event with two dish antennas, one measuring 18 m and the other 32 m.

Chandrayaan-1’s liquid engine was fired when the spacecraft passed at a distance of about 500 km from the moon to reduce its velocity to enable lunar gravity to capture it into an orbit around the moon. The spacecraft is now orbiting the moon in an elliptical orbit that passes over the polar regions of the moon. The nearest point of this orbit (periselene) lies at a distance of about 504 km from the moon’s surface while the farthest point (aposelene) lies at about 7502 km. Chandrayaan-1 takes about 11 hours to go round the moon once in this orbit.

The performance of all the systems onboard Chandrayaan-1 is normal. In the coming days, the height of Chandrayaan-1 spacecraft’s orbit around the moon will be carefully reduced in steps to achieve a final polar orbit of about 100 km height from the moon’s surface. Following this, the Moon Impact Probe (MIP) of the spacecraft will be released to hit the lunar surface. Later, the other scientific instruments will be turned ON sequentially leading to the normal phase of the mission.

It may be recalled that Chandrayaan-1 spacecraft was launched on October 22, 2008 by PSLV-C11 from India’s spaceport at Satish Dhawan Space Centre (SDSC) SHAR, Sriharikota. As intended, PSLV placed the spacecraft in a highly oval shaped orbit with a perigee (nearest point to Earth) of 255 km and an apogee (farthest point to Earth) of 22,860 km. In the past two weeks, the liquid engine of Chandrayaan-1 has been successfully fired five times at opportune moments to increase the apogee height, first to 37,900 km, then to 74,715 km, later to 164,600 km, after that to 267,000 km and finally to 380,000km, as planned. During this period, the Terrain Mapping Camera (TMC), one of the eleven payloads (scientific instruments) of the spacecraft, was successfully operated twice to take the pictures, first of the Earth, and then moon.

With today’s successful manoeuvre, India becomes the fifth country to send a spacecraft to Moon. The other countries, which have sent spacecraft to Moon, are the United States, former Soviet Union, Japan and China. Besides, the European Space Agency (ESA), a consortium of 17 countries, has also sent a spacecraft to moon.

courtesy: www.isro.org

Chandrayaan-1 enters Deep Space

26 Oct 2008

Chandrayaan-1 spacecraft has entered deep space after crossing the 150,000 km (one and a half lakh km) distance mark from the Earth. This happened after the successful completion of the spacecraft’s third orbit raising manoeuvre today (October 26, 2008) morning.

During this manoeuvre which was initiated at 07:08 IST, the spacecraft’s 440 Newton liquid engine was fired for about nine and a half minutes. With this, Chandrayaan-1 entered a much higher elliptical orbit around the Earth. The apogee (farthest point to Earth) of this orbit lies at 164,600 km while the perigee (nearest point to Earth) is at 348 km. In this orbit, Chandrayaan-1 takes about 73 hours to go round the Earth once.

The antennas of the Indian Deep Space Network at Byalalu are playing a crucial role in tracking and communicating with Chandrayaan-1 spacecraft in such a high orbit. The spacecraft performance is normal. More orbit raising manoeuvres are planned in the coming few days to take Chandrayaan-1 towards the Moon.

Chandrayaan-1 Spacecraft’s Orbit Raised Further

25 Oct 2008

The second orbit-raising manoeuvre of Chandrayaan-1 spacecraft was carried out at 05:48 hrs IST this morning (October 25, 2008) when the spacecraft’s 440 Newton Liquid Engine was fired for about 16 minutes by commanding the spacecraft from Spacecraft Control Centre (SCC) at ISRO Telemetry, Tracking and Command Network (ISTRAC) at Peenya, Bangalore. With this engine firing, Chandrayaan-1’s apogee has been further raised to 74,715 km, while its perigee has been raised to 336 km. In this orbit, Chandrayaan-1 spacecraft takes about twenty-five and a half hours to go round the Earth once. This is the first time an Indian spacecraft has gone beyond the 36,000 km high geostationary orbit and reached an altitude more than twice that height.

It may be recalled that Chandrayaan-1, India’s first spacecraft to Moon, was successfully launched by PSLV-C11 on October 22, 2008 from Satish Dhawan Space Centre SHAR, Sriharikota. The launch vehicle placed Chandrayaan-1 in an elliptical orbit with a perigee (closest point to earth) of 255 km and apogee (farthest point to earth) of 22,860 km. The first orbit-raising manoeuvre was performed on October 23, 2008 by firing the spacecraft’s liquid engine for 18 minutes resulting in the increase of the spacecraft orbit’s apogee to 37,900 km and the perigee to 305 km. The Indian Deep Space Network (IDSN) at Bylalu is tracking the spacecraft in the present orbit, receiving signals in S and X bands and is sending commands to the spacecraft.

All systems onboard the spacecraft are functioning normally. Further orbit raising maneuvers to take Chandrayaan-1 to still higher orbits are planned in the next few days.

Chandrayaan-1 Spacecraft’s Orbit Raised

23 Oct 2008

The first orbit-raising manoeuvre of Chandrayaan-1 spacecraft was performed at 09:00 hrs Indian Standard Time (IST) this morning (October 23, 2008) when the spacecraft’s 440 Newton Liquid Engine was fired for about 18 minutes by commanding the spacecraft from Spacecraft Control Centre (SCC) at ISRO Telemetry, Tracking and Command Network (ISTRAC) at Peenya, Bangalore. With this engine firing, Chandrayaan-1’s apogee has been raised to 37,900 km, while its perigee has been raised a little, to 305 km. In this orbit, Chandrayaan-1 spacecraft takes about 11 hours to go round the Earth once.

Chandrayaan-1, India’s first spacecraft to Moon, was successfully launched by PSLV-C11 yesterday (October 22, 2008) from Satish Dhawan Space Centre SHAR, Sriharikota. The launch vehicle placed Chandrayaan-1 in an elliptical orbit with a perigee (closest point to the earth) of 255 km and apogee (farthest point to earth) of 22,860 km. In this initial orbit, Chandrayaan-1 orbited the Earth once in about six and a half hours. Following its successful launch, the SCC acquired the first signals and conducted preliminary operations on Chandrayaan-1. The Deep Space Network (DSN) at Bylalu tracked the spacecraft in this orbit and received signals in S and X band and has sent commands to the spacecraft.

All systems onboard the spacecraft are functioning normally. Further orbit raising maneuvers are planned in the coming few days.

chandrayan

Chandrayaan-1 spacecraft undergoing pre-launch tests



Moon Impact Probe integration with Chandrayaan-1 spacecraft



Moon Impact Probe



Readying Chandrayaan-1 spacecraft for Thermovac test




Fully integrated Chandrayaan-1 spacecraft (left) and loading it to Thermovac Chamber (right)