Hello Space Fans and welcome to another edition of Space Fan News. In this episode, many of
you have by now heard of the loss of ISRO’s Vikram Lander and Pragyan Rover as they made
their descent to the lunar surface on September 7th this year. Since that time, mission planners
in India along with help from NASA have been working to figure out what happened.
Just as war and conflict have their blunders, space exploration has seen its fair share
of mishaps. These include tragedies and failed endeavours, such as the explosion of Space
Shuttle Challenger, the fire in Apollo 1’s capsule, the crashing of the Mars Climate
Orbiter, the Crash of ESA’s Schiaparelli Mars lander and most recently, the crash of
India’s advanced moon lander, Vikram. Which has been a turbulent and upsetting episode
for India’s Space Research Organization. The reason for the Chandrayaan-2 mission was
first and foremost to explore the south pole of the Moon to look for water. Atremis, NASA
program for getting humans back to the moon, is planning on sending the landers here because
the prospects for water here are among the best you’re gonna find on the surface of
the Moon. Not only are the implications of finding water
on the Moon great, but scientists have suspected the shadows of the Moon’s South Pole to
contain ice since the 1960s. These are literally places where the Sun don’t shine so any
ice formed there doesn’t sublimate, it stays right there. The importance of this research
cannot be overstated. Water is essential for a successful long-term human lunar presence.
For example, not only can we drink it, but water drawn from the Moon could be broken
into its constituent elements, hydrogen and oxygen, which we can use as rocket fuel. This
could turn the Moon into an excellent jumping off point to Mars because rockets would be
saved from carrying water as payload for part of the journey, making the trip a little easier.
ISRO, India’s space agency, boasts a range of fantastic achievements in aerospace engineering,
including sending an orbiter to Mars. So expectations were high when India launched their latest
advanced craft, the Chandrayaan-2 orbiter, with the aims to land a rover on the Moon
and survey the frozen water composition of the South Pole.
So let’s take a look at what happened last summer.
After launching on the 22nd of July, Chandrayaan began its perilous journey through the cold
depths of space to the Moon, reaching lunar orbit on August 20th.
As Chandrayaan-2 rounded its fifth polar orbit, it once again cruised across the Vikram lander’s
planner touchdown site - six hundred kilometres from the Moon’s South Pole and between the
Simpelius N and Mazinus C craters. What mission control witnessed next was an extremely complex
release manoeuvre between the Chandrayaan-2 Orbiter and India’s most advanced lander
ever. In the process of disconnecting from its orbiter,
Vikram began a series of immaculately planned deorbiting manoeuvres, guided by an assembly
of leading-edge onboard computers. Programmed to make flight decisions in real-time, the
built-in systems considered masses of data from an array of highly precise velocity,
height, altitude, direction and positioning measuring instruments.
This systematic methodology placed India in an ideal position to attempt its first soft-landing
on another celestial body. Using five rocket engines and eight attitude control thrusters,
the descent process involved reducing Vikram’s speed from 1,680 metres per second to almost
zero within thirteen minutes, a remarkable feat by any standard. Yet while Vikram zoned
in on the rocky outcrop of its target below, little did India know that the following minutes
- the culmination of years of devoted research - would be fateful.
Beginning with the first stage, four out of five engines onboard Vikram burst into flames
to slow it down to about 150 metres per second, and the lander descended from an altitude
of 30km to 7.4km. Next came the Absolute Navigation Phase. Angling to align its cameras properly
to calibrate vital parameters, Vikram began to deviate from its intended 45-degree inclination.
Automatically and immediately kicking in, Vikram’s engines over-calibrated and threw
the craft into a full rotation. Entering the Final Braking Speed Phase in a state of hopeless
chaos, Vikram’s onboard computers battled with the lander’s somersault rotation for
control as it swept from side to side, before communication was abruptly cut off at about
2.1km above the Moon’s surface. Then, silence.
Exact reasons for Vikram’s descent failure are still uncertain, but there are many theories.
It could be that the somersault motion was caused by a malfunction in the lander’s
propulsion systems during the end of the Rough Brake Phase and the Absolute Navigation Phase.
It should be no surprise that the integration of new technology in Vikram’s engines could
have caused one of them to misfire or over-calibrate. Others have instead suggested that the problem
was in the Vikram computer’s software, saying that its logic was flawed, resulting in the
lander completing a full accidental turn. Many believe it was a combination of these
issues. What is for sure is that we haven’t heard
a peep from Vikram since the 7th of September. Immediately after contact with the craft was
lost, the Indian Space Research Organization, or ISRO, launched an investigation into the
circumstances surrounding the crash. The meticulous diagnostic process required careful analysis
of Vikram’s flight data, although NASA and ISRO are taking stabs in the dark to diagnose
the fate of Vikram. One report from ISRO on September 9th was
that the lander is in one piece but was in a tilted position.
With the help of the internet, it is easy to stay updated on events like these. An IRSO
official said, “I think finding link after so many days is going to be extremely difficult
but, there is nothing wrong in trying.” As a result of growing concerns regarding
Vikram’s fate, ISRO released a statement which underlines the procedures undertaken
to salvage the mission. “The orbiter of Chandrayaan-2 has located Vikram lander, but
no communication has been made with it yet. All possible efforts are being made to establish
communication with the lander.” Every passing day following the crash plunged
the South Pole further into the darkness of the lunar night. NASA has been looking but
so has been unable to locate the crashed lander when they pass over its landing site. NASA’s
Lunar Reconnaissance Orbiter has been unable to identify the Vikram lander in the orbital
images taken probably because the lunar dusk casts long shadows across the Moon’s surface.
It would be really nice if they could image the lander because then we’d have some more
clues to help understand what happened. Still though, even if they see it, this does not
mean they will certainly be able to establish a connection with it. A hard crash could have
made it impossible for the lander to communicate with Earth and damaged its antenna so that
it couldn’t broadcast signals to Chandrayaan-2. Not to mention there is no solar power in
the lunar night and Vikram may have perished in the cruel sub-zero temperatures.
So the latest updates so far is that ISRO’s headquarters in Bengaluru have stopped all
attempts to connect with the lander. Whether or not we will ever find out exactly
what happened to India’s first lunar lander, the event will be marked in space history.
The Vikram crash has stunned NASA and stands as a stark reminder to the nine Commercial
Lunar Payload Services companies that soft-landings on the Moon are easier said than done.
Principal Director of space systems at Draper, Seamus Tuohy, told the press that “it does
remind us that it is difficult to complete 100% the entire mission, but I think it motivates
us to make sure that, when we go, that we’re successful.”
Although the loss is upsetting, it is just a single failure amongst many successes of
the overall mission. Not only did it prove that India could engineer an advanced orbiter
and lander and sent it to the moon, but the manoeuvre of separating the orbiter and lander
was particularly spectacular. Although the lander has been lost, the orbiter
can still go about its mission and survey the South pole of the moon. Rather than the
estimated single year of operation, the orbiter has enough fuel onboard to be able to orbit
the Moon for about seven and a half years. India’s Prime Minister Modi has proclaimed
that in spite of the landing failure, India is proud of the ISRO’s numerous achievements.
Regardless of the lander’s final verdict, the loss of Vikram will be a crucial failure
for India to learn from. Well that’s it for this episode Space Fans,
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Thanks to all of you for watching and as always, Keep Looking Up!