Landing on the Moon’s South Pole

Scientists believe that some of those answers might be lurking on the surface of our most familiar neighbor... the Moon. And now, the Indian Space Research Organization, or ISRO, is next to launch their lunar mission, and if successful, India will be the first country to land on the Moon’s south pole. The moon actually carries the undisturbed record of the solar system’s chaotic beginnings, making this hunk of rock a prime destination for exploration. But it hasn’t been easy to get up there and soft landings are tricky to accomplish. And ISRO’s mission, called Chandrayaan-2, will get to the Moon riding India’s most powerful rocket, the Geosynchronous Satellite Launch Vehicle Mark III. Standing at roughly 43 meters tall and four meters wide, this vehicle is designed to carry over four thousand kilograms of payload into Geosynchronous Transfer Orbit, and over twice that amount into low-Earth orbit. But this will be its first trip to our lunar friend. Chandrayaan-2 isn’t ISRO’s first pursuit to the Moon.

Back in 2008, they launched Chandrayaan-1, which consisted of just a single orbiter, but that little spacecraft helped confirm the presence of water on the Moon; including water ice, or hydroxyl molecules, spread across the Moon’s north and south pole regions. The presence of such a resource like water could help us with future deep space exploration technologies, like a mission to Mars, or even building a sustainable environment for a moon base. But before we dive into lunar colonies, we need to take a closer look at what the Moon has to show, and ISRO is starting with the South Pole. The South Pole, in particular, is a special place since water ice is observed to be nestled in craters that are permanently shadowed. These craters are known to never reach above -250 degrees Celsius and may harbor up to several hundred million tons of water ice.

To optimize such a treasure trove of material, the Chandrayaan-2 mission is composed of a lot more than its predecessor. “Unlike the predecessor Chandrayaan-1, which has just an orbiter. This has an orbiter, land rover, configuration. It has a suite of instruments on all of these three platforms.” So, this is a big mission consisting of an orbiter, a lander module called Vikram, named after the father of the Indian Space Program, and a six-wheeled rover named Pragyan, meaning “wisdom” in Sanskrit. All these parts will carry a series of payloads unique to their platform to study the lunar topography, seismography, mineral identification and distribution, surface chemical composition, and temperatures of the moon.

And all of these aspects are important since there are different kinds of water ice ISRO is looking out for. “If you see the planetary system, you have mainly three different types or sources of water. One is from the endogenous processes, which are primordial in nature. The second is from external sources, like an asteroid and cometary impacts. The third is in-situ production of water, or hydroxyl compounds. So, the Moon is really interesting because now it has been established that on the Moon we have these three different kinds of water present, which is like exceptional. But we don't know how they interact with each other and how we should see this as a complete process.” Sriram worked on the Dual Frequency Synthetic Aperture Radar instrument that’s aboard the orbiter and it could help identify this process. “So Chandrayaan-2 has a two-frequency radar instrument, which is like completely new.

It operates at L and S bands that are, 23 centimeters and 12 centimeters respectively. If you combine these two measurements taken at these different wavelengths, you can have a depth profile of the surface. So, the chief idea is to differentiate between rough terrains along with the terrains containing water ice.” So, while the orbiter takes to the skies to map water ice beneath the surface, the Pragyan rover is blasting topsoil with lasers – searching for concentrations of elements that could have been part of a magma ocean from 4 billion years ago. “One works on Alpha particle X-ray emission and fluorescent spectroscopy. So, you blast alpha particles through a surface and then measure X-ray fluorescence and X-ray emission spectrum. And the other payload, which is the LIBS, is laser-induced spectroscopy, so you use lasers to shoot the surface and then characterize the plasma.” Okay, well right about now, you’re probably wondering how will we be getting any of this information back to us? Well, this is where our Vikram lander comes in. Vikram will be in communications with Pragyan and anything the rover finds will be reported back to Earth via the Indian Deep Space Network.

The orbiter will operate independently with the IDSN so the team can contact it no matter where it is in its orbit. So all in all, this is a complicated and highly impressive endeavor from the ISRO team. While the scientific findings of this mission will have vital future implications for space exploration, this is also a major mission for ISRO. It will showcase their innovative engineering as they continue to make international headlines as a sustainable and reliable agency. In their latest achievement, they sent 104 satellites into orbit on a single rocket, beating out the previous title held by Russia by nearly three times over. This is one of many missions that ISRO is planning to explore space, and if Chandrayaan-2 lands on the moon in September 2019, the whole world will be waiting to see what this mission will bring. There are so many things we didn’t get to about this mission and many of ISRO’s other projects, but if you want to know more, let us know in the comments below! And if you liked this episode, make sure to tune into Discovery’s Confessions from Space: Apollo, airing on July 20th.