The big expense in getting people to orbit or the moon or any other space destination is the cost of escaping the Earth’s gravity. One often-proposed solution involves building a giant space elevator from some point on the Earth to orbit. That sounds great, but the reality is the materials needed to make a giant stalk reaching from the ground to orbit don’t exist today. Cables or other structures for such an elevator would have to be so impossibly thick as to break under their own weight. However, a recent paper from a researcher at Cambridge and another at Columbia suggest that while you can’t build an elevator from the Earth’s surface to orbit, we may have the technology to build a tunnel that anchors on the moon and lets out in Earth’s orbit.
Before you dismiss the idea out of hand, have a look at the paper. A classic space elevator proposal has one point on Earth and the far end balanced with a counterweight keeping the cables under tension. The proposed lunar elevator would minimize these problems by having most of the bulk in space and on the moon.
India’s Chandrayaan-2 mission to the Moon was, in a word, ambitious. Lifting off from the Satish Dhawan Space Centre on July 22nd, the mission hoped to simultaneously deliver an orbiter, lander, and rover to our nearest celestial neighbor. The launch and flight to the Moon went off without a hitch, and while there were certainly some tense moments, the spacecraft ultimately put itself into a stable lunar orbit and released the free-flying lander so it could set off on its independent mission.
Unfortunately, just seconds before the Vikram lander touched down, an anomaly occurred. At this point the Indian Space Research Organisation (ISRO) still doesn’t know exactly what happened, but based on the live telemetry stream from the lander, some have theorized the craft started tumbling or otherwise became unstable between three and four kilometers above the surface.
In fact, for a brief moment the telemetry display actually showed the Vikram lander completely inverted, with engines seemingly accelerating the spacecraft towards the surface of the Moon. It’s unclear whether this was an accurate depiction of the lander’s orientation in the final moments before impact or a glitch in the real-time display, but it’s certainly not what you want to see when your craft is just seconds away from touchdown.
But for Chandrayaan-2, the story doesn’t end here. The bulk of the mission’s scientific goals were always to be accomplished by the orbiter itself. There were of course a number of scientific payloads aboard the Vikram lander, and even the Pragyan rover that it was carrying down to the surface, but they were always secondary objectives at best. The ISRO was well aware of the difficulties involved in making a soft landing on the Moon, and planned their mission objectives accordingly.
Rather than feel sorrow over the presumed destruction of Vikram and Pragyan, let’s take a look at the scientific hardware aboard the Chandrayaan-2 orbiter, and the long mission that still lies ahead of it.
Here on Earth, the ability to generate electricity is something we take for granted. We can count on the sun to illuminate solar panels, and the movement of air and water to spin turbines. Fossil fuels, for all their downsides, have provided cheap and reliable power for centuries. No matter where you may find yourself on this planet, there’s a way to convert its many natural resources into electrical power.
But what happens when humans first land on Mars, a world that doesn’t offer these incredible gifts? Solar panels will work for a time, but the sunlight that reaches the surface is only a fraction of what the Earth receives, and the constant accumulation of dust makes them a liability. In the wispy atmosphere, the only time the wind could potentially be harnessed would be during one of the planet’s intense storms. Put simply, Mars can’t provide the energy required for a human settlement of any appreciable size.
The situation on the Moon isn’t much better. Sunlight during the lunar day is just as plentiful as it is on Earth, but night on the Moon stretches for two dark and cold weeks. An outpost at the Moon’s South Pole would receive more light than if it were built in the equatorial areas explored during the Apollo missions, but some periods of darkness are unavoidable. With the lunar surface temperature plummeting to -173 °C (-280 °F) when the Sun goes down, a constant supply of energy is an absolute necessity for long-duration human missions to the Moon.
Since 2015, NASA and the United States Department of Energy have been working on the Kilopower project, which aims to develop a small, lightweight, and extremely reliable nuclear reactor that they believe will fulfill this critical role in future off-world exploration. Following a series of highly successful test runs on the prototype hardware in 2017 and 2018, the team believes the miniaturized power plant could be ready for a test flight as early as 2022. Once fully operational, this nearly complete re-imagining of the classic thermal reactor could usher in a whole new era of space exploration.
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.
It’s been fifty years since man first landed on the Moon, but despite all the incredible advancements in technology since Armstrong made that iconic first small step, we’ve yet to reach any farther into deep space than we did during the Apollo program. The giant leap that many assumed would naturally follow the Moon landing, such as a manned flyby of Venus, never came. We’ve been stuck in low Earth orbit (LEO) ever since, with a return to deep space perpetually promised to be just a few years away.
But why? The short answer is, of course, that space travel is monstrously expensive. It’s also dangerous and complex, but those issues pale in comparison to the mind-boggling bill that would be incurred by any nation that dares to send humans more than a few hundred kilometers above the surface of the Earth. If we’re going to have any chance of getting off this rock, the cost of putting a kilogram into orbit needs to get dramatically cheaper.
Luckily, we’re finally starting to see some positive development on that front. Commercial launch providers are currently slashing the cost of putting a payload into space. In its heyday, the Space Shuttle could carry 27,500 kg (60,600 lb) to LEO, at a cost of approximately $500 million per launch. Today, SpaceX’s Falcon Heavy can put 63,800 kg (140,700 lb) into the same orbit for less than $100 million. It’s still not pocket change, but you wouldn’t be completely out of line to call it revolutionary, either.
Unfortunately there’s a catch. The rockets being produced by SpaceX and other commercial companies are relatively small. The Falcon Heavy might be able to lift more than twice the mass as the Space Shuttle, but it has considerably less internal volume. That wouldn’t be a problem if we were trying to hurl lead blocks into space, but any spacecraft designed for human occupants will by necessity be fairly large and contain a considerable amount of empty space. As an example, the largest module of the International Space Station would be too long to physically fit inside the Falcon Heavy fairing, and yet it had a mass of only 15,900 kg (35,100 lb) at liftoff.
To maximize the capabilities of volume constrained boosters, there needs to be a paradigm shift in how we approach the design and construction of crewed spacecraft. Especially ones intended for long-duration missions. As it so happens, exciting research is being conducted to do exactly that. Rather than sending an assembled spacecraft into orbit, the hope is that we can eventually just send the raw materials and print it in space.
NASA needed a small and lightweight computer to send humans on their journey to the Moon and back, but computers of the day were made out of discrete components that were heavy, large, complicated, and unreliable. None of which are good qualities for spaceflight. The agency’s decision to ultimately trust the success of the Apollo program on the newly developed integrated circuit was an important milestone in computer history.
Given the enormity of the task at hand and the monumental effort it took, it’s surprising to learn that there aren’t very many left in existence. But perhaps not as surprising as the fact that somebody apparently threw one of them in the trash. A former NASA contractor happened to notice one of these historic Apollo Guidance Computers (AGC) at an electronics recycling facility, and thankfully was able to save it from getting scrapped.
The AGC was actually discovered in 1976, but it was decided to get the computer working again in time for the recent 50th anniversary of the Moon landing. A group of computer scientists in California were able to not only get the computer up and running, but integrate it into a realistic simulator that gives players an authentic look at what it took to land on the Moon in 1969.
Restoring a computer of this age and rarity is no easy feat. There aren’t exactly spare parts floating around for it, and the team had to go to great effort to repair some faults on the device. Since we covered the beginning stages of the restoration last year, the entire process has been extensively documented in a series of videos on YouTube. So while it’s unlikely you’ll find an AGC in your local recycling center, at least you’ll know what to do with it if you do.
Humans first walked on the moon 50 years ago, yet there are some people who don’t think it happened. This story is not about them. It turns out there was another great conspiracy theory involving a well-known astronomer, unicorns, and humanoids with bat wings. This one came 134 years before the words “We chose to go to the moon” were uttered.
The 1835 affair — known as the Great Moon Hoax — took the form of six articles published in The Sun, a newspaper in New York City. Think of it like “War of the Worlds” but in newspaper form — reported as if true but completely made up. Although well-known astronomer John Herschel was named in the story, he wasn’t actually involved in the hoax. Richard Adams Locke was the reporter who invented the story. His main goal seemed to be to sell newspapers, but he also may have been poking fun at some of the more outlandish scientific claims of the day.