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| India-Pakistan |
| Crucial Indian lunar probe manoeuvre today |
| 2008-11-08 |
| NEW DELHI: A crucial manoeuvre, to be performed on Saturday, on Chandrayaan-1 will inject it into an orbit around the moon from its current highly elliptical orbit around the earth. On November 4, the last of the earth-bound manoeuvres was carried out, which put the satellite into an orbit with an apogee (the farthest point in the orbit from the earth) of 3,84,000 km and a perigee (the nearest point) at 1,019 km. With this apogee, the satellite actually encircles the moon as well. However, this earth-bound orbit is actually at about an inclination of 18 degrees to the earth's Equator. Since the final designated lunar orbit is a circumpolar one, this orbit has also to turn around by almost 90 degrees. As the satellite cruises along its present trajectory, the moon's gravity will begin to dominate when this orbit will be about 60,000 km from the moon, which is expected to happen around midnight on Friday. Under the gravitational pull, the satellite will also begin to gain velocity. The orbit plane will also begin to gradually tilt away from its present near-equatorial one. |
| Posted by:john frum |
| #5 so why is repeating the historical accomplishments of the last generation(-25 yrs) at huge expense to a starving population noteworthy? |
| Posted by: Skidmark 2008-11-08 22:44 |
| #4 So....is this gonna effect the nex EID? |
| Posted by: .5MT 2008-11-08 16:07 |
| #3 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 They were aiming for 500km periselene and 7500km aposelene. Not bad from 400,000 km away. I guess the Chinese can now assume that the stellar navigation on Indian missile RVs works just fine. |
| Posted by: john frum 2008-11-08 13:57 |
| #2 Chandrayaan-1 Successfully Enters Lunar Orbit 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. |
| Posted by: john frum 2008-11-08 13:19 |
| #1 Some good news for a change. |
| Posted by: g(r)omgoru 2008-11-08 04:17 |