On 56th indepence day, August 15 2003, India’s Prime Minister Atal Bihari Vajpayee announced. “Our country is now ready to fly high in the field of science. I am pleased to announce that India will send her own spacecraft to the moon by 2008. It is being named Chandrayaan-1″. In Sanskrit (language of Ancient India) “Chandrayaan” means “Moon Craft”.
Moon has always fascinated Indians from ancient days and now 21st century india is ready to land on moon! Chandrayaan-1 is the first mission towords the dream.
In Chandrayaan-1, the lunar craft would be launched using Polar Satellite Launch Vehicle (PSLV) weighing 1304 kg at launch and 590 kg at lunar orbit. Lunar craft would orbit around moon 100 km from moon surface.
Objective
Scientific Objectives
The Chandrayaan-1 mission is aimed at high-resolution remote sensing of the moon in visible, near infrared (NIR), low energy X-rays and high-energy X-ray regions.
Specifically the objectives are:
i) To prepare a three-dimensional atlas (with high spatial and altitude resolution of 5-10 m) of both near and far side of the moon.
ii)To conduct chemical and mineralogical mapping of the entire lunar surface for distribution of mineral and chemical elements such as Magnesium, Aluminum, Silicon, Calcium, Iron and Titanium as well as high atomic number elements such as Radon, Uranium & Thorium with high spatial resolution.
The Simultaneous photo geological, mineralogical and chemical mapping through Chandrayaan-1 mission will enable identification of different geological units to infer the early evolutionary history of the Moon.
The chemical mapping will enable to determine the stratigraphy and nature of the Moon’s crust and thereby test certain aspects of magma ocean
Mission Objectives
1.To realise the mission goal of harnessing the science payloads, lunar craft and the launch vehicle with suitable ground support systems including Deep Space Network (DSN) station.
2.To realise the integration and testing, launching and achieving lunar polar orbit of about 100 km, in-orbit operation of experiments, communication/ telecommand, telemetry data reception, quick look data and archival for scientific utilisation by scientists.
Mission Sequence
(sorry but i have obtained this data from the ISRO webite so it may be a bit too technical for your liking..)
1:Chandrayaan-1 spacecraft was launched from the Satish Dhawan Space Centre, SHAR, Sriharikota by PSLV-XL (PSLV-C11) on 22 October 2008 at 06:22 hrs IST in an highly elliptical initial orbit (IO) with perigee (nearest point to the Earth) of 255 km and an apogee (farthest point from the Earth) of 22,860 km, inclined at an angle of 17.9 deg to the equator. In this initial orbit, Chandrayaan orbited the Earth once in about six and a half hours.
2:Subsequently, the spacecraft’s Liquid Apogee Motor (LAM) firing was done on 23 October at 09:00 hrs IST, when the spacecraft was near perigee, to raise the apogee to 37,900 km while the perigee to 305 km. The spacecraft took eleven hours to go round the Earth once.
3:The orbit was further raised to 336 km x 74,715 km on 25 October at 05:48 hrs IST. In this orbit, spacecraft took about twenty-five and a half hours to orbit the Earth once.
4:The LAM was fired again on 26 October at 07:08 hrs IST to take the Chandrayaan-1 spacecraft to extremely high elliptical orbit with apogee 164,600 km and perigee at 348 km. Chandrayaan-1 took about 73 hours to go round the Earth once
5:On 29 October, orbit raising was carried out at 07:38 hrs IST to raise the apogee to 267,000 km and perigee to 465 km. Chandrayaan’s present orbit extends more than half the way to moon and takes about six days to orbit the Earth
6:On 4 November at 04:56 hrs IST, Chandrayaan entered the Lunar Transfer Trajectory with an apogee of 380,000 km
7:On November 8 at 16:51 hrs IST, the spacecraft’s Liquid engine was fired to reduce its velocity to insert the spacecraft in the Lunar orbit (LOI) and enable lunar gravity to capture it. As a result, the spacecraft goes in an elliptical orbit with periselene (nearest point to the moon) of 504 km and aposelene (farthest point from the moon) of 7,502 km
8:The first orbit reduction manoeuvre has been carried out successfully on November 9 at 20:03 hrs IST. The spacecraft is now in lunar orbit with 200 km periselene. The aposelene remains unchanged (i.e 7,502 km).
9:After careful and detailed observation, a series of three orbit reduction manoeuvres were successfully carried out and the spacecraft’s orbit was reduced to its intended operational 100 km circular polar orbit on November 12
10: On 14 November at 20:06 hrs IST, the Moon Impact Probe (MIP) was ejected from the Chandrayaan-1 spacecraft and hard landed on the lunar surface near the South Polar Region at 20:31 hrs IST after 25 minutes journey. It placed the Indian tricolour, which was pasted on the sides of MIP on the Moon.
11: Currently, the scientific instruments/payloads are being commissioned sequentially and exploration of Moon with the array of onboard instruments have begun.
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