Why is it Still So Hard to Land on the Moon?

Why is it Still So Hard to Land on the Moon?

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How hard can it be to safely land on the moon? after all, it’s not like we haven’t done it before.

Since 2013 there have been at least nine attempts at a soft landing on the moon by China, India, Japan, Israel as well as the US and Russia, if you don’t include the ones which failed before they got to the moon, but only four have landed successfully and three of those were Chinese.

It is almost as if we have forgotten how to do these things that we spent the equivalent of hundreds of billions of dollars and over 10 years perfecting, but after Apollo, the moon lost its appeal and we switched our interests for almost 50 years, but now the moon is back, big time.

The last people to walk on the moon were the crew of Apollo 17, who left on the 19th of December 1972, which was almost 52 years ago, but we didn’t stand still, here is just a tiny selection of what we did after the moon.

NASA repurposed the remains of the Apollo program, mostly the Saturn 5s, and created America’s first manned space station, Skylab in 1973.

In 1977, the voyager probes were sent off the outer planets and now they are at the edge of the solar system or in interstellar space and still going.

The Space shuttle was launched in 1981 and lasted until 2011, and in 1990 the space shuttle lifted the Hubble space telescope into orbit which transformed our view of space and allowed us to see further back in time than we have ever done before to the very early universe.

The International Space Station became operational in 2000 and has been occupied ever since. We have sent robotic probes to every planet in the solar system and successfully landed ten uncrewed landers and rovers on Mars, we have even landed on a comet, returned samples from an asteroid, and flown through the sun’s lower corona.

We now have rocket boosters that are bigger and twice as powerful as the Saturn 5 that will soon be able to return and land by themselves so they can be reused many times, dramatically cutting the cost of getting into space.

Science and technology has come on in huge leaps and bounds and yet getting a spacecraft to land safely on the moon still seems to be one of the most challenging tasks, so why is this?

Well, looking back to the original space race between the US and the Soviets can give us a lot of clues.

This was an international race between two superpowers with differing ideologies and it was as much the projection of these ideologies through their achievements in space as about national pride and as such each one spent a huge amount of time, money, and resources on their respective programs. The Apollo program cost about 2.5% of U.S GDP per year for a 10-year period in the 1960s, in total terms it was over $300 Billion in 2024 money.

Back then everything that was being done was new and had not been done before and it certainly was not an easy ride.

We knew almost nothing about the surface of the moon and it was thought by more than a few scientists at NASA that the lunar dust could be so deep and soft that a lander could just sink into it or keel over so much that it would not be able to take off and return to earth.

So, before any Manned Apollo missions, NASA had to find out what it was like on the surface and the only way to do that was to send robotic landers to analyze the regolith or lunar soil and see if it was possible to soft-land on the moon.

The first ones weren’t so much landers as impactors. This was the Ranger program of 1959, a planned series of 9 missions, each one was to crash into the surface of the moon at varying places and take TV images on the way down that would be beamed back to Earth up until impact.

Of the nine attempts, the first six failed, usually because the rocket blew up on the launch pad or shortly after, and on the sixth one the camera failed as it approached the moon. The Rangers soon gained the nickname of the “Shoot and Hope” program.

Only the last 3 missions worked as planned and the program cost the equivalent of $1.21 billion for today.

This was followed by the Surveyor missions, seven of which were sent from June 1966 through January 1968 although the preparation for the missions had been going since 1960.

In fact, both programs had been the headline missions for the US to match or exceed the Soviet lunar orbiters and landers which had beaten the U.S to the moon up until Kennedy announced the Apollo program in May 1961

This was a big gamble for the U.S to take, to do something that was way out of everyone’s comfort zone and something they knew would be very difficult for the Soviets to compete against, both from a technological and economic standpoint and certainly in the 8-year time frame given by Kennedy for the U.S to put men on the moon and safely return them by the end of the decade.        

This relegated Ranger and  Surveyor programs to be the support acts, now gathering data on how manned missions could be done.

 Five of the seven Surveyor missions landed safely on the surface to complete their missions and all of them are still there.

These were the first NASA spacecraft to soft land on the moon and were just four months after the Soviet Luna 9 which was the first spacecraft to land safely on the lunar surface.

In 1969, Apollo 12 landed close by Surveyor 3 and Astronaut Pete Conrad removed the camera and brought it back to Earth so it could be studied to see how the unfiltered sun’s UV and particle radiation had affected it over its 2-½ years on the moon.  

These missions were the testing ground to prove the technology that would later be used by the Apollo landers and included the most critical space engineering challenges of the time, namely the descent guidance and control system, steerable, throttleable engines, and the radar systems required for determining the lander’s altitude and velocity.

There was just no way to fully test these flights here on Earth and simulate landing on the moon with its thermal and radiation environments and deceleration with no atmospheric resistance from 2.6 km/s relative to the Moon before firing retrorockets to a soft landing about 3 minutes 10 seconds later at 3m per second.

The cost of the Surveyor missions was $469 million which in today’s money is about $4.4 billion.

Now many might think that we don’t need to prove that we can land on the moon and we can just copy what we did last time but there is a problem.

The technology today is very different from that of the 1960s, just look at a car made in the 60s and one made today, they do the same job and look pretty similar but under the skin they are very different with even a modest new car is filled with microcomputers and electronics controlling everything from touch activated door handles to the infotainment systems and everything else in-between, these would be unrecognizable to a 1960s mechanic, and the same thing has happened to spacecraft.

Virtually everything has changed, even the type of engines being used are not the same as the Apollo lunar landers. Then they used hypergolic fuels, a fuel and oxidizer that ignited in contact with each other, ideal for the depths of space and the lunar surface, but they are very dangerous to handle and toxic and you can’t make them from basic materials that you would find on the moon.

The new landers will use cryogenic fuels such are liquid methane or hydrogen and Oxygen, the latter can be made from water ice which we believe is available in the permanently shaded craters at the moon’s poles.

However, these have to be started with an ignition source like a spark and have to be 100% reliable, if the engines don’t start on the descent to the surface of the moon, it will be a short one-way journey.  

The new moon landers will use Lidar which uses lasers instead microwaves and rader to produce much narrower beams which have fewer issues with scattering and returning false echoes from a wide area. The landing will be controlled by a computer and use cameras and A.I to look for the best landing spot to avoid boulders and craters and all of this needs to be tested in the harsh lunar environment.

All these things will need human-rated before they can be used for manned missions, it’s effectively like starting all over again although we still retain the general knowledge from the Apollo missions and this is why things are taking so long and not always going to plan.

NASA is also doing things differently this time and instead of building things in-house they are subcontracting often small companies to build experimental landers on what would be considered a shoestring budget. 

The Intuitive Machines Nova-C, the mission which took place on the 22nd February 2024 with the IM-1 lunar lander cost $118 million and was part of the Artemis program under the NASA Commercial Lunar Payload Services or CLPS program which will use small cheap missions to test and prove critical technology. If some fail it won’t be a game stopper or will have cost too much money.

The Nova-C mission will be a follow-on from the 2010 NASA Project Morpheus to build a vertical take-off and vertical landing vehicle with a nontoxic spacecraft propellant system using methane and oxygen and an autonomous landing and hazard detection technology.

The IM-1 lunar lander, named Odysseus was the first US-made lander to return to the moon in over 50 years and was the first spacecraft to use methalox, methane oxygen rocket engine to navigate between the Earth and landing on the moon.

The IM-1 was also was to use lidar to detect the distance from the surface and velocity, though that was made inoperable by the safety override that should have been removed before the flight being left on.

However, the payload also included a separate NASA-built Lidar which was there for testing purposes, which when it was discovered that the main lidar wasn’t working was software patched from Earth to work with the navigation system.

The rough landing was caused by the lander coming in slightly faster than expected and when it landed, one of the support legs broke causing it to fall over on a upward slope of a small crater.  It ended up leaning over at a 30 degree angle with one of the solar panels facing the ground which limited power production and the main antenna pointing away from the vertical which reduced the signal strength back to Earth.

Now this could be seen as a failure, but it is part of the “move fast and break things” methodology and still proved a lot of the technology used, even under the extreme circumstances. It was a very low-cost mission at $118 million, compared to the Artemis One mission which was about $4.2 billion to fly around the moon and return the empty crew capsule back to the earth.

For the NASA Artemis mission, the will be two more missions as part of the Intuitive Machines Nova-C project.  These will deploy the TRIDENT ice drill to sample ice from below the lunar surface and the Micro Nova Hopper which will work as a standalone hopper lander to hop in to difficult-to-reach areas such as deep craters on the lunar surface as well as other new instruments and sensors.

When it comes to the actual Artemis manned flights, NASA will choose between the SpaceX and Blue Origin landers closer to the time and after each has been tested on the moon.

So in answer to the question, why is it so difficult to land on the moon, it is because we have simply left it a long time and we have to start again to catch up on the 50-year gap.

If we had continued with the moon missions after Apollo, the changes would have been gradual as new tech became available and we would have bases on the moon and probably bases on Mars by now, and all of this would be something that would have been easy to afford if we didn’t spend vast sums of money on perfecting ways to kill each other, but that’s a whole other story for another day.

So, Thanks for watching and a big thank you goes to our Patreons for their ongoing support.

Paul Shillito
Creator and presenter of Curious Droid Youtube channel and website www.curious-droid.com.

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