On July 22, India began an ambitious mission to simultaneously deliver an orbiter, lander and rover to the moon. Launched from the Satish Dhawan Space Center on the GSLV Mk III home rocket, Chandrayaan-2 is expected to enter lunar orbit on August 20. If all goes well, the mission's lander module will land on September 7.
Attempting a multi-faceted mission of this kind is a bold move, but the Indian Space Research Organization (ISRO) has experience. Launched in 2008, the Chandrayaan-1 mission has spent almost a year in lunar orbit. This mission also included the so-called Moon Impact Probe (MIP), which deliberately hit the surface near Shackleton Crater. MIP was not designed to survive the impact, but still provided India with a shortlist of countries that have placed the object on the surface of the moon.
If the Chandrayaan-2 lander component was named Vikram after India's space pioneer Vikram Sarabhai can safely land on the moon's surface, this will be a historic achievement for ISRO. To date, the only countries that have made a controlled landing on the moon are the Soviet Union, the United States and China. At the beginning of the year, it seemed that Israel would secure its position as the fourth country to accomplish this feat Sheet the spaceship, but the last second of damage caused the ship to hit the surface. Loss Sheet, although unfortunate, gave India an unexpected chance of taking the fourth place it desired despite Israel's advantage.
We have a few months before the big event, but so far everything has gone according to plan for Chandrayaan-2. In anticipation of the news that the spacecraft has successfully entered orbit around the moon, let's take a closer look at how this ambitious mission should work.
Robots don't have to hurry
Given that on the 50th anniversary of Apollo 11 everyone is talking about the moon again, you probably realize that Neil Armstrong, Michael Collins and Buzz Aldrin have not spent months crammed into a relatively small command module. They went both ways, including the expedition to the surface of the Moon, in just eight days. So if it only took a few days in 1969 to reach the moon, why would Chandrayaan-2 take the same journey in 2019?
Put simply, accelerated transport to the moon and back was necessary for the people on board. For each day they were in the capsule, the crew needed air for breathing, food for food, and drinking water. Because of this human element, Apollo missions took the shortest possible path: direct transfer from Earth's orbit to the gravitational sphere of the Moon. To perform the maneuver, known as Trans-Lunar Injection (TLI), they needed an incredibly powerful rocket that could accelerate the spacecraft to the necessary speed. Enter the mighty Saturn V, which is still the record for the most powerful rocket ever launched.
To be honest, with a mass of about 8.5% of the Apollo spacecraft, Chandrayaan-2 would certainly not need a rocket as powerful as Saturn V to perform a similar TLI. However, he would need one with a slightly larger kick than GSLV Mk III, which was designed to lift geosynchronous communication satellites. Placing the spacecraft on a geostationary transfer orbit accelerates it to almost, but not enough, speed to get to the moon. Because of this, Chandrayaan-2 will have 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 the only passengers Chandrayaan-2 Vikram lander and Pragjan rover, there is nothing to complain about that Economy are flying. It is noteworthy that the commercial launch provider could certainly have directed the mission to a more direct path to the moon, but there is some aspect of national pride associated with the fact that Chandrayaan-2 is completely "native."
Assuming that a successful Moon Capture will occur on August 20 or around this year, Chandrayaan-2 will then proceed to several more ignition of the engine to gradually lower its orbit around the Moon, and the final goal will be a circular orbit at an altitude of 100 kilometers. The spacecraft's orbiter module will stay in this orbit for a year or more, supporting a set of instruments designed to study the surface of the moon, including high resolution cameras and synthetic aperture radar.
While the orbiter remains above, the symbol Vikram the lander will disengage and begin preparing for the descent. First, he will adjust his orbit to move it over the southern region of the Moon at an altitude of 30 kilometers, where it will scan the surface to find a suitable landing site. When the vehicle performs a series of self-checks, it will set fire to it, which will rest on September 7 near the South Pole pool – Aitken. This area has been selected for its relatively flat topology and interesting mineral deposits.
Landing time is important because the goal is to bet Vikram on the surface at the beginning of the lunar day, which lasts 14 Earth days. Since the ship is not expected to survive another moonlit night, any landing delays will shorten surface time. Landing too late on a lunar day has shortened the Chinese mission Chang & # 39; e 4, which ISRO will certainly want to avoid thanks to Chandrayaan-2.
On the surface, Vikram has a number of instruments at its disposal, including a seismometer and temperature probes. It also has a laser retroreflector system built by NASA Goddard Space Flight Center that will allow orbiting satellites to accurately measure distances when they fly overhead. But the real attraction of the mission will appear when the ramp is lowered for Pragjan wanderer.
recalling Sojourner NASA rover implemented on Mars, Pragjan will navigate the lunar surface with stereoscopic 3D cameras and perform observations with laser and X-ray spectroscopes. The rover will travel approximately 500 meters Vikram, using the lander as a communication relay between it and ground control on Earth.
Success by degree
Space travel is already extremely difficult, but controlled landing in another world and surviving long enough to conduct useful science is even more difficult. There is a reason why few countries were able to accomplish this feat. Nine attempts took the Soviet Union before they could give humanity the first close-up view of the moon's surface in 1966, and the United States broke several Forester-class probes before they even tried to land Surveyor 1. Given the historical precedent, "ambitious" can be a kind of understatement when talking about the placement of an orbiter, lander and rover in the same mission.
But the important thing to remember is that no matter what happens, the Indian Space Research Organization will be able to collect important data and gain invaluable experience in the real world. If Vikram falls too hard, or Pragyana the ramps will definitely be a disappointment. But it won't be a waste.