Moon mission unit busy as the clock ticks

via TOI

BYALALU (off Bangalore-Mysore highway): The huge, white dish antenna gradually rotates, acting on the commands given out by the control panel. Inside the telemetry centre below the antenna are engineers tapping command keys and peeking curiously into some signals. They are tracking some stars that are lightyears away from the Earth - the Cassiopeia and Tauras.

At the nondescript village Byalalu, 40 km off Bangalore, which smacks of poverty and underdevelopment, is this Rs 100 crore Deep Space Network (DSN) set up by the ISRO Telemetry Tracking and Command Network to track the country's first unmanned spacecraft for the Moon mission project, Chandrayaan-1.

Chandrayaan being scheduled for October (the September schedule has been postponed), the countdown has already begun for DSN. The station is the back-end support system and spacecraft signal monitoring unit set up on a 135-acre plot.

The DSN gains importance, more so, after the spacecraft crosses 1 lakh km-distance from Earth as other ISRO stations can monitor only up to this distance. The spacecraft, once launched, takes 300 hours to orbit the Moon and has a lifespan of about two years.

"We were given a timeline to prepare for the mission. We are fully ready and are doing the qualifying tests. Since the system is up and running, we are tracking the stars that are very far from Earth," say engineers at the station.

The DSN has the indigenous 32-metre dia dish antenna, a joint venture of Bhabha Atomic Research Centre and the Electronics Corporation of India Limited which is the biggest so far in India. Another small antenna - 18 mtr dia - is a back-up for the big dish. Both the antennae will play a key role in Chandrayaan-1 and also Chandrayaan-2, the second Indian Moon mission, slated for a launch after about four years.

Keeping fingers crossed and hoping for the best!

Moon mission likely in October: ISRO

Chandrayan 1 Ready to go, groundwork for Chandrayan 2 being layed out

via TOI

CHENNAI: India's "ambitious" unmanned
lunar mission 'Chandrayan' is likely to soar into the skies in October second week, Indian Space Research Organisation Chairman G Madhavan Nair said on Wednesday.

"The satellite integration is almost complete. And we would be entering the thermovac in about a week's time. It takes about 45-50 days for the launch after thermovac, after which we would declare the date," he told reporters here.

"The earliest is October," he said. As for the climatic conditions, October was favourable, and ISRO has to look at the appropriate alignment between planets also before deciding on the launch window, he said.

"We do not have the flexibility of launching the mission on any date," he added.

"The payloads have been integrated at the satellite centre in Bangalore... you can see the full spacecraft there," Nair said about the Rs 3.8 billion unmanned mission.

He also said that India had signed MoU with Russia for the Chandrayan 2 project, which will have an Orbiter that would go around the moon and a Lander or Rover which would collect samples from moon's surface after landing on it.

"We hope to achieve this mission by 2011-12," he said. On India's manned mission to the moon, he said ISRO would set into motion building of a capsule for this purpose, the project report for which was awaiting Government approval.

"It is going with good speed. Soon the process will be completed," he said.

SOURCE

Chandrayan 1 Mission Preparations Progressing Well

Preparations on for moon mission

via Hindu

CHENNAI: Preparations have begun for the launch of Chandrayaan-1, India’s moon mission, with the stacking of the stages of the Polar Satellite Launch Vehicle (PSLV-C11) under way at Sriharikota in Andhra Pradesh from July 21. Simultaneously, the Chandrayaan-1 spacecraft, with its 11 payloads from India and abroad, has been assembled fully at the ISRO Satellite Centre (ISAC), Bangalore. A 32-metre-diameter dish antenna is ready at Byalalu village near Bangalore to track the spacecraft during its 3,84,400 km journey to the moon. If the campaign goes as planned, the PSLV-C11, which is a more powerful version and is called PSLV-XL, will put Chandrayaan-1 in orbit on September 19.

Top officials of the Indian Space Research Organisation said: “We have started stacking the PSLV at Sriharikota for the Chandrayaan-1 mission. We are now building the first stage. The launch campaign has begun. We are moving the various stages from the Vikram Sarabhai Space Centre (VSSC) in Thiruvananthapuram and the Liquid Propulsion Systems Centre at Mahendragiri in Tamil Nadu to Sriharikota.”

M. Annadurai, Project Director, Chandrayaan-1, called it “a national mission with international participation and India as the captain.” He said from Bangalore, “All the 11 payloads of the spacecraft have been integrated fully. The next milestone is to go for the thermo-vacuum tests.” These entail the creation of space-like vacuum in a big chamber at the ISAC. Mr. Annadurai said: “The fully integrated Chandrayaan-1 will be subjected to tests in the vacuum-like space environment. It will go through tests in minus 120 degrees Celsius and searing hot temperatures.”

After the thermo-vaccum tests, it would go through vibration tests to test its integrity. The spacecraft would later be moved to Sriharikota, he said.

The PSLV-XL is a more powerful vehicle than the normal PSLV. It is suffixed with XL because its strap-on booster motors are extra long.

S. Ramakrishnan, Director (Projects), VSSC, said: “A PSLV has six strap-on motors. A normal strap-on will use nine tonnes of solid propellants. But XL will have 12 tonnes of propellants in each strap-on. We have also extended the length of the strap-ons from ten metres to 13.5 metres. That is why it is called XL – extra long.”

The PSLV-XL is a four-stage vehicle with a weight of 316 tonnes and a height of 44.4 metres. Chandrayaan-1 will weigh 1,304 kg on the earth but 590 kg when it orbits the moon at an altitude of 100 km.

The PSLV-XL would put Chandrayaan-1 in a long, elliptical orbit with an apogee of 22,000 km and a perigee of 200 km.

Mr. Ramakrishnan explained how Chandrayaan-1 would reach the moon from this transfer orbit: “You fire the apogee kick motor [on board the spacecraft] to extend the ellipsis from 22,000 km to about half a million km. That is how it reaches the vicinity of the moon. Once it nears the moon, Chandrayaan-1’s velocity is reduced by rotating the spacecraft in the opposite direction. It is called retro-firing. Its velocity is reduced so that the moon’s gravity will capture Chandrayaan-1 and it will be in moon’s orbit.”

From an altitude of 100 km above the moon’s surface, Chandrayaan-1’s payloads will be used to investigate the moon’s minerals and chemical properties, detect the presence of water, if any, on the lunar surface, map the moon’s surface and look for clues on its origin and evolution.

One of Chandrayaan-1 payloads called Moon Impact Probe (MIP) will be ejected after the spacecraft reaches the lunar orbit.