Aug. 20 (UPI) — Some 30 days after liftoff, India’s Chandrayaan-2 spacecraft successfully entered the moon’s orbit on Tuesday after performing one of the mission’s most difficult maneuvers, the nation’s space agency said.
The spacecraft began orbiting the moon following the completion of a lunar orbit insertion maneuver that took approximately 28 minutes to execute, the Indian Space Research Organization said.
ISRO Chairman Kailasa Vadivoo Sivan said it was one of the most difficult maneuvers of the probe’s mission as the smallest mistake could have potentially doomed the entire project.
“A higher-than-expected approach velocity would have bounced off the spacecraft into deep space while a slow approach would have led to the moon’s gravity to pull Chandrayaan-2 and crash it on the lunar surface,” he said Tuesday after the craft had entered the moon’s orbit. “The approach velocity had to be just right and the altitude over the moon rather precise. Even a small error would have killed this mission.”
He said that with the successful completion of the lunar orbit insertion maneuvre, the spacecraft had hit “a major milestone” and was now orbiting the moon at an inclination of 88 degrees.
Next, it is to perform a series of orbit maneuvres to enable it to enter its final pass over the lunar poles at a distance of about 62 miles from the moon’s surface, before the lander, Vikram, separates and enters its own orbit around the moon.
The lander will then perform a series of braking maneuvers to “soft land in the south polar region of the moon on Sept. 7,” the ISRO said in a statement.
After landing, Vikram will release Pragyan, the rover.
Chandrayaan-2 launched from India’s Geosynchronous Satellite Launch Vehicle in July and had been circling the Earth for the past few weeks, slowly using its propulsion system to increase its orbital distance to escape’s its gravity.
“On Sept. 7, at 1:55 a.m., lander will land on the moon,” Sivan said. “Whatever is humanly possible has been done by us.”
The next lunar-bound orbit maneuver is scheduled for Wednesday, ISRO said.
Chandrayaan-2: India Spacecraft Begins Orbiting Moon
Image copyright AFP Image caption The rocket weighs as much as a fully-loaded jumbo jet
India’s second lunar exploration mission has entered the Moon’s orbit, nearly a month after blasting off, officials have said.
Chandrayaan-2 began its orbit of the Moon at 09:02 local time (04:32 GMT) on Tuesday.
The craft completed the manoeuvre in around 30 minutes, the Indian Space Research Organisation (Isro) said.
India’s Prime Minister Narendra Modi hailed the mission as “an important step in the landmark journey”.
K Sivan, head of Isro, said he was confident Chandrayaan-2 would land on the Moon as planned on 7 September.
“Whatever is humanly possible, has been done by us,” he told reporters at a news conference.
Chandrayaan-2 was launched from the Sriharikota space station on 22 July, a week after the scheduled blast-off was halted due to a technical snag.
India hopes the $145m (£116m) mission will be the first to land on the Moon’s south pole. Last month’s launch was the beginning of a 384,000km (239,000-mile) journey.
‘Our hearts almost stopped’
Mr Sivan said Chandrayaan-2’s successful entry into the Moon’s orbit was a make-or-break moment for the mission.
The craft, which comprises three parts – an orbiter, a lander and a rover – used an on-board propulsion system to complete the tricky operation.
Mr Sivan said the speed and altitude of the craft had to be “just right” because “even a small error would have killed the mission”.
“Our heartbeats increased… for 30 minutes, our hearts almost stopped,” Mr Sivan said.
Now Chandrayaan-2 has entered the Moon’s orbit, it will carry out a series of manoeuvres in the coming days before its lander attempts to touch down next month.
What is this mission all about?
India’s first lunar mission, Chandrayaan-1, was launched in 2008 but it did not land on the lunar surface. However it carried out the first and most detailed search for water on the Moon using radars.
Chandrayaan-2 (Moon vehicle 2) will try to land near the little-explored south pole of the Moon.
The mission will focus on the lunar surface, searching for water and minerals and measuring moonquakes, among other things.
India used its most powerful rocket, the Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk-III), in this mission. It weighed 640 tonnes (almost 1.5 times the weight of a fully-loaded 747 jumbo jet) and, at 44 metres (144ft), was as high as a 14-storey building.
The spacecraft used in the mission has three distinct parts: an orbiter, a lander and a rover.
The orbiter, which weighs 2,379kg (5,244lb) and has a mission life of a year, will take images of the lunar surface.
The lander (named Vikram, after the founder of Isro) weighs about half as much, and carries within its belly a 27kg Moon rover with instruments to analyse the lunar soil. In its 14-day life, the rover (called Pragyan – wisdom in Sanskrit) can travel up to a half a kilometre from the lander and will send data and images back to Earth for analysis.
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Media captionIs India a space superpower?How long is the journey to the Moon?
The journey of more than six weeks is a lot longer than the four days the Apollo 11 mission 50 years ago took to land humans on the lunar surface for the first time.
In order to save fuel, India’s space agency has chosen a circuitous route to take advantage of the Earth’s gravity, which will help slingshot the satellite towards the Moon. India does not have a rocket powerful enough to hurl Chandrayaan-2 on a direct path. In comparison, the Saturn V rocket used by the Apollo programme remains the largest and most powerful rocket ever built.
Chandrayaan-2 Successfully Enters Lunar Orbit. Here’s The Moon Landing Plan
BENGALURU: In a major milestone for Isro, the Chandrayaan-2 spacecraft entered the Moon’s orbit early on Tuesday (August 20).”Our heart was almost stopping”, was how Isro chairman K Sivan described the tense moment when team Chadrayaan-2 attempted to inject the spacecraft into the lunar orbit. As Isro scientists started firing Chandrayaan-2’s onboard liquid engine to put the spacecraft in an orbit around the Moon, Sivan said “our heartbeat increased”.”For 30 minutes, our heart was almost stopping,” he told a press conference after the Lunar Orbit Insertion (LOI) maneuver was completed successfully at 09.02 am as planned, using the onboard propulsion system.But Sivan said the proposed soft-landing on the Moon on
September 7 at 1.55am
is going to be a “terrifying” moment as it is something Isro has not done before, whereas LOI maneuver had been carried out successfully during the Chandrayaan-1 mission.”Now the tension has only increased, not reduced,” he said. However, Isro was confident about the soft-landing.Chandrayaan-2 is carrying a total of 14 payloads — 13 Indian and one passive payload from Nasa — with special focus of the orbiter on mapping craters in the polar region, besides checking for water again.The project, which has cost India Rs 978 crore, has seen wide participation from institutions from around the country. “Nearly 500 universities and 120 industries have played a role in GSLV MkIII and Chandrayaan-2 respectively. And, 80% and 60% of the cost has gone to these,”
Isro chief Sivan had said.What nextNow, Isro needs to perform a few operations before attempting to soft-land the spacecraft’s lander, Vikram, with a probe on the Moon early on September 7.Isro will perform four more manoeuvres on August 21, 28, 30 and September 1 to take the spacecraft to lower orbits and eventually make it settle in a 100km×100km orbit, where it will spend the remainder of its life.After the final manoeuvre on September 1, Chandrayaan-2 is likely to be in a 114km×128km orbit. Once it enters this orbit, Vikram, carrying the rover Pragyan, will separate from the orbiter four days before landing. “The final descent of the lander will be 15 terrifying minutes, because it’s something we’ve never tried before,” Isro chief Sivan said. “It is one of the most complex operations we’ve ever handled.” After separating from the orbiter, Vikram will need to reach a 30km×100km orbit around the Moon.Vikram will start its descent from a height of 30km. A little over 10 minutes later it will be 7.4km from the lunar surface. After 89 seconds, and at an altitude of 400m, Vikram will hover for 12 seconds over the pockmarked surface of the moon as it gathers data vital to a safe landing.It will then descend, in 66 seconds, to 100m from the lunar surface and hover there for 25 seconds as its onboard instruments decide if it should land on the preferred site or a second assigned one.”If it can land on the first site,
Vikram will reach a height of 10m from the lunar surface in the next 65 seconds, while significantly reducing its velocity. It will be a vertical descent,” a scientist said. “In case it has to pick the second site, it will use 40 seconds to first descend to a height of 60m, then further drop to 10m in 25 seconds.” From a height of 10m, Vikram will take 13 seconds for a soft touchdown. “All five of its engines will be firing during this time,” another scientist said. “We initially planned to turn them off at a height of 10m, but have now decided to allow the engines to run till sensors tell them to shut off once the four legs of the lander touch the surface.”Vikram will send back to Earth its first pictures after touchdown some 15 minutes later. After four hours, Pragyan will crawl out of the lander.In Video:Chandrayaan-2 successfully enters Moon’s orbit.