India Launched A Moon Orbiter, Lander, And Rover All In One Shot With Chandrayaan-2

On July 22nd, India launched an ambitious mission to simultaneously deliver an orbiter, lander, and rover to the Moon. Launched from the Satish Dhawan Space Centre on a domestically-built GSLV Mk III rocket, Chandrayaan-2 is expected to enter lunar orbit on August 20th. If everything goes well, the mission’s lander module will touch down on September 7th.

Attempting a multifaceted mission of this nature is a bold move, but the Indian Space Research Organisation (ISRO) does have the benefit of experience. The Chandrayaan-1 mission, launched in 2008, spent nearly a year operating in lunar orbit. That mission also included the so-called Moon Impact Probe (MIP), which deliberately crashed into the surface near the Shackleton crater. The MIP wasn’t designed to survive the impact, but it still secured India a position on the short list of countries that have placed an object on the lunar surface.

If the lander component of Chandrayaan-2, named Vikram after Indian space pioneer Vikram Sarabhai, can safely touch down on the lunar surface it will be a historic accomplishment for the ISRO. To date, the only countries to perform a controlled landing on the Moon are the Soviet Union, the United States, and China. Earlier in the year, it seemed Israel would secure its position as the fourth country to perform the feat with their Beresheet spacecraft, but a last second fault caused the craft to crash into the surface. The loss of Beresheet, while unfortunate, has given India an unexpected chance to take the coveted fourth position despite Israel’s head start.

We have a few months before the big event, but so far, everything has gone according to plan for Chandrayaan-2. As we await word that the spacecraft has successfully entered orbit around the Moon, let’s take a closer look at how this ambitious mission is supposed to work.

Robots Don’t Need to Rush

Apollo Trans-Lunar Injection

Considering that Apollo 11’s 50th anniversary has gotten everyone talking about the Moon again, you’re probably aware that Neil Armstrong, Michael Collins, and Buzz Aldrin didn’t spend months crammed into the relatively tiny Command Module. They made the round-trip, including their excursion to the lunar surface, in just eight days. So if it only took a few days to reach the Moon in 1969, why will it take Chandrayaan-2 months to make the same trip in 2019?

Put simply, the accelerated transit to the Moon and back was necessitated by the humans onboard. For every day they were in the capsule, the crew needed air to breathe, food to eat, and water to drink. Because of this human element, the Apollo missions took the shortest route possible: a direct transfer from Earth orbit to the Moon’s gravitational sphere of influence. To perform the maneuver, known as Trans-Lunar Injection (TLI), they needed an incredibly powerful rocket that could accelerate the spacecraft to the necessary velocity. Enter the towering Saturn V, which still holds the record for the most powerful rocket ever put into operation.

Chandrayaan-2 projected orbit

Now to be fair, with a mass of approximately 8.5% of the Apollo spacecraft, Chandrayaan-2 certainly wouldn’t need a rocket as powerful as the Saturn V to perform a similar TLI. But it would need one with a bit more kick than the GSLV Mk III, which was designed for lifting geosynchronous communication satellites. Putting a spacecraft into a geostationary transfer orbit accelerates it to a velocity that’s almost, but not quite, enough to get to the Moon. Because of this, Chandrayaan-2 will need to make up the difference with a series of burns designed to gradually raise its orbit over the next few weeks.

This method of reaching the Moon would be completely impractical for a human mission. But with Chandrayaan-2’s only passengers being the Vikram lander and Pragyan rover, there’s nobody to complain about the fact they’re flying Economy. It’s worth noting that a commercial launch provider could certainly have put the mission on a more direct route to the Moon, but there’s a certain aspect of national pride involved in Chandrayaan-2 being entirely “homegrown”.

Lunar Operations

Assuming a successful lunar capture on or around August 20th, Chandrayaan-2 will then proceed to make several more engine burns to gradually lower its orbit around the Moon, with the ultimate goal being a circular orbit at an altitude of 100 kilometers. The orbiter module of the spacecraft will remain in this orbit for a year or more, operating a suite of instruments designed to study the Moon’s surface, including high resolution cameras and synthetic aperture radar.

Vikram lander with Pragyan rover visible

While the orbiter remains above, the Vikram lander will detach and begin preparations for descent. It will first adjust its orbit to take it over the Moon’s southern region at an altitude of 30 kilometers, where it will scan the surface for an appropriate landing site. Once the vehicle has performed a series of self-checks, it will perform a landing burn that will bring it to rest in the vicinity of the South Pole–Aitken Basin on September 7th. This area was selected due to its relatively flat topology and interesting mineral deposits.

The timing of the landing is important, as the goal is to put Vikram on the surface at the beginning of the lunar day, which lasts for 14 Earth days. As the craft is not expected to survive the subsequent lunar night, any delay in landing will result in a reduced amount of time to conduct science on the surface. Landing too late in the lunar day cut short China’s Chang’e 4 mission, a fate which the ISRO will surely want to avoid with Chandrayaan-2.

On the surface, Vikram has a number of instruments at its disposal, including a seismometer and temperature probes. It’s also carrying a laser retroreflector array built by NASA’s Goddard Space Flight Center which will allow orbiting satellites to take precise distance measurements when they pass overhead. But the real highlight of the mission will come when the ramp is lowered for the Pragyan rover.

Resembling the Sojourner rover NASA deployed on Mars, Pragyan will navigate on the lunar surface with 3D stereoscopic cameras and perform observations with its laser and x-ray spectroscopes. The rover will travel approximately 500 meters away from Vikram, using the lander as a communications relay between it and Ground Control on Earth.

Success by Degrees

Space travel is already exceptionally difficult, but making a controlled landing on another world and surviving long enough to conduct useful science is even more challenging. There’s a reason so few countries have been able to pull off the feat. It took the Soviet Union nine attempts before they were able to give humanity the first up-close view of the lunar surface in 1966, and the United States crashed several Ranger-class probes before they even attempted to land Surveyor 1. Given historic precedent, “ambitious” might be something of an understatement when talking about deploying an orbiter, lander, and rover all in the same mission.

But the important thing to remember is that, no matter what happens, the Indian Space Research Organisation will be able to collect important data and gain invaluable real-world experience. If Vikram comes down too hard, or Pragyan’s ramp jams, it will surely be a disappointment. But it won’t be a waste.

56 thoughts on “India Launched A Moon Orbiter, Lander, And Rover All In One Shot With Chandrayaan-2

  1. Finally, I’ll be able to get a good curry on the moon! Seriously though this is an ambitious project and I wish them well, just wish the west still did this sort of thing.

  2. Great article about the technology, and I applaud the audacity of the ISRO mission. Hopefully the mission is a success. I then unfortunately read the comments. It is a shame that so many people have put artificial and insurmountable limits on their own intelligence.

  3. It’s not always about the destination, but it’s the journey getting there, that is the real value of doing these things. If they make a few discoveries on he moon, those are just a bonus. A whole lot of people were/are involved in this project. While focused on every little detail, they were less likely sitting around the house making more babies to feed. It gets people thinking about getting some of their kids a better education, so they can get involved in these wonderful journeys, rather than following the traditional path of procreation. Passing out free food, is nice for short term emergencies, but a bad long term solution. It reduces value of the things most people work hard to obtain. More jobs, gives people the operatunity to earn what they need, and forces them to consider how many kids they wish to support. Knowing there will always be food on the table, regardless if you work for it, or the number of children you have, doesn’t give much incentive to work at all, or limit family size.

    A lot of new technology is developed, new ways of getting the job done, tools and devices. Many of which find uses outside of the space programs. The discoveries of greatest value, aren’t always out in space, it’s in the technology developed to get there.

  4. @Christopher Dubé (@RealChrisDube)
    I am always dismayed by the comments about ‘there are so-and-so many people in poverty, yet we spend so-and-so amount on ‘. Did you know that ISRO is now launching satellites for other countries and generating a hefty revenue ? There are more than one ways to solve a problem and usually advance science provides good options. These kind of comments just show ignorance and apathy.

    1. John you are absolutley right. Some of the folks and by and large even some western countries want to project INDIA i poverty etc.
      They must know Chandrayaan 2 is an eye opener and massive revenue generator.
      I liked your minute observation

    1. This is a tight Budget mission..half of the cost of the Avengers movie..Its not about becoming a Super power..its about a dream ,a mission and the motivation to attain a goal and milestone to pass on to the next generation

  5. At one point India had the most advanced civilization in the world. For various reasons, she got behind and now she is trying to catch up. Yes, she need to focus on the poverty alleviation, improve quality of living for the millions with solutions that are unique for the situation, take care of environment, and explore space too along the way. No one has right to judge. If you’d like sit back and watch how all of that is done while balancing everything with democracy.

  6. Good for you, India!

    What saddens me most (also reading the comments section) is always this nationalistic thingy.

    We’re in 2018! This is a *global* effort (as is getting rid of poverty!). We should work together. Nations are so 1850.

    1. You miss out on a vital factor here. Nations are vital for population control. Virtually every species that regulates its own population is territorial. We would do better if we were MORE territorial, not less, unless you think the population explosion-boom starvation-bust cycle sounds like a good time.

    2. So true. ISRO learnt a lot from those pioneering missions from USSR and USA. There is no comparison of the novelty factor faced by those missions 60 years ago compared to this one. On other hand having a space program is essential for poverty elevation. It punches way above its weight in RoI when it comes to that. Recycling imported trash and exporting natural resources and undergarments will not solve poverty.

      1. bullshit. ISRO didn’t “learn” anything from those “pioneering missions” – USA even bullied boris yelstin of Russia into walking away from its contractual obligation for cryogenic engines while making false & ridiculous excuses that the cryogenic engine tech might be used for missile making! ENVY was in plain sight… it delayed India’s mission by 10 years but India went ahead and built it on their own anyway…

        1. It is pointless to argue that ISRO did not learn anything from those early pioneering missions. It is independent of geopolitical games like how US nixed the ToT component of cryo deal with Glavkosmos (knowing very well that Indian strategic missile program is not eyeing a theoretical but genuine capability based off solid and earth storable propellents and not cryogenics) or how Russia/USSR, Europe and even US helped Indian space program at various points of its development.

          Co-operation in science always have a way to hoodwink nationalistinc tribalism. Thats the best hope for humanity.

  7. What’s great so see here is that despite some intolerant attitude from some people, there still are a others with a positive mindset who applaud others nation’s development.

  8. English, Russian, Chinese, Hindi & Hebrew … It sounds like we are trying to build the Tower of Babel again. Let’s hope that it works out better this time.

    Seriously, Good Luck to everyone trying to get us back to the Moon! Let’s plan on setting up a permanent home this time. I think maybe God is willing to host a few guests. But we must be careful to not wear out our welcome by squabbling once we get there.

    Yay, India! Better luck next time, Israel! Go, Team!!

    1. The part of Genesis mentioning the Tower of Babel may have a double meaning. Not only is it part of the creation story, it may also be prophetic. Man builds his tower to the heavens and then is dispersed vastly and diversification happens. At least I like to entertain that idea, be it true or otherwise. Time to build that space elevator. :-) I can’t wait until we really get started spreading out into space, where we belong…leaving the womb and growing up. Having India participate will be helpful for all of us.

  9. People who try to make fun should realize that India has great technological abilities, and they are enormously practical. They take off the shelf technology and say, “what can we do with this?” … they orbited a probe around Mars for a fraction of the cost of probes by the US, Russia, or the ESA. It’s still working!
    Kudos to this mission and to India.

    1. Their is no off the shelf space technology. Countries guard their space tech very jealously. The Mars launcher was a PSLV, which had scores of successful launches before it was used for the Mars mission.

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