I was reading on the BBC about a proposed mission to interstellar space.
The Interstellar Probe, proposed by John Hopkins University, could be a truly exciting endeavour, breaching the Heliosphere, the outermost limit of our suns magnetic field, and venturing into interstellar space, viewing our solar system from the outside and studying the nature of space and radiation between the stars.
The only spacecraft to date to reach this far from home were Voyager 1 and 2. Launched in the late 1970’s to visit the planets in the outer solar system, they kept travelling outwards after fulfilling their missions, and forty years later officially left the solar system; though they weren’t carrying the right instruments to properly explore this new domain.
Assuming the Interstellar Probe took fifteen years to build (not unusual for such an expensive and demanding mission) and a similar time to get there as it took Voyager, a lot of the people reading this wouldn’t be around to see it arriving at its destination, let alone see the analysis of what it discovered.
This isn’t only trues for and interstellar mission. Any mission to the outer plants using conventional chemical rocket propulsion will always to take a very long time to get to its destination. Cassini–Huygens took seven years to get to Saturn. And given the very long flight time, it becomes even more important that the spacecraft is built hardy enough to ensure it will survive for such a long flight, which in itself will require longer to even build it in the first place.
That’s not a reason not to undertake such missions, and certainly national space agencies and those that work for them are happy to start such work knowing fully that only their successors, even their descendants, will see it’s mission completed. But wouldn’t it be good if we could find a way to get there faster?
Certainly, as someone in the second half of their life, I’d be a fan of that idea.
In the following articles I will explore different propulsion technologies and mission scenarios for travelling these long distances, generally for robotic missions, but some maybe applicable for crewed missions as well.
The last fortnight has been a game changer for those who dream of being able to fly into space.
Over the last six decades, hundreds of people have left the confines of the Earth and its atmosphere. But with the exception of half a dozen civilians who have paid tens of millions for stays at Russian and American space stations, every astronaut has been a highly educated and trained pilot, engineer or scientist, sent to further our knowledge and experience with space. The opportunities for ordinary people to fulfil their “science fiction dream” have not been there.
Two weeks ago, though, space tourism for the masses took a giant leap towards reality.
On 11th July 2021 Virgin Galactic launched its SpaceShip Two spaceplane up to a height of 90km (above the American definition of where space starts). It’s four passengers, which Included Richard Branson, Virgins founder, got to see the dark sky of space, the curvature of the Earth, and spend five minutes in zero gravity.
SpaceShip Two. Credit: Virgin Galactic
Virgin Galactic currently has plans to build a fleet of four such space planes, and start commercial passenger flights next year. Given that all parts of the launch system are reusable, this could potentially service hundreds of passengers a year. They already have a waiting list of 600 people who have paid a deposit for the $250,000 ticket to space.
Less than a fortnight later, one of Virgin Galactic’s main competitors, Blue Origin, launched their own reusable sub-orbital space rocket called New Shepherd, climbing up up to 105km. It’s founder, Jeff Bezos, and three other passengers, enjoyed a similar experience provided by Virgin. Bezos, too, intends to provide this as an ongoing service to customers, though exactly when and how many is not yet clear. Whilst he hasn’t yet started selling tickets, or even taking deposits for flights, he had 7,600 people apply when he auctioned off the spare seat on the first flight (the winner bid $28 million!!)
New Shepherd blasting off. Credit: Blue Origin
Clearly there are a lot of people willing to pay a lot of money to travel to space.
But have these ground breaking achievements come too late?
Both companies have spent nearly two decades getting to this point. Branson initially envisaged starting his launch services as early as 2007, but a series of mishaps and set backs, including an explosion of a test tank which killed three engineers, and a crash of a prototype which killed the co-pilot, meant that this target was missed by nearly a decade and a half.
Blue Origin has found their development timeline a similarly challenging road.
If either company had been ready to fly in the first decade of this century, they would now have many flights under their belts, and an established business model. Flights to space would be a normal, if expensive and brief, holiday destination.
But a decade later there is big competition. SpaceX, lead by Elon Musk, as been busy developing reusable rockets that don’t just fly up to space and back for a five minute joy ride, they fly into orbit. This requires much more powerful rockets, and sophisticated and reliable re-entry systems.
In March 2019, Musk started flying NASA astronauts to the International Space Station in his Crewed Dragon spacecraft, lofted into space on top of the now reliable, and reusable rocket, Falcon 9 rocket.
SpaceX Crewed Dragon docked with the ISS. Credit: NASA
In August this year, SpaceX are due to start orbital test flights of a much bigger craft, Starship. This is designed to carry up to 100 passengers at a time, up into orbit, perhaps eventually to someone’s space hotel. In the future the rocket is expected to be able to take similar numbers of people to the moon, or even to Mars.
There is no clear timeline for when fare paying passengers might ride in Starship, or how much a ticket might cost to. Right now, Musk seems to be focusing on enabling America to return its astronauts to the moon, where they have not trodden since the start of the 1970’s, and to establish a permanent scientific base.
But it can’t been too long before he turns his attention to providing the space experience to the masses. Musk has a track record of attempting big things, and more often than not, succeeding at them.
So if you were given the choice of paying hundreds of thousands of dollars for a few minutes in space, or a trips that could last hours or days in orbit, which would you take?
Branson and Bezos may only have a few years in the sunshine before their spacecraft become old hat, and they find their customer base starts to disappear.
Comparison of offerings of Virgin, Blue Origin and SpaceX
NASA’s Mars Helicopter is still going strong. It has survived its first five planned flights, exceeding its expected life span. It is now embarking on a new set of flights, which rather than just confirming its flight capabilities, will put it to work assisting Perserverance
This is really exciting. Perseverance is on its way to Mars, but hey, just another rover.
But Ingenuity is a Martian Helicopter! How exciting is that? I can’t wait to see it in action.
Ingenuity will be deployed from under the belly of Perserverance, then take off using two counter rotating blades. It is repowered by a solar panel on the top, and keeps in communication wirelessly with Perserverance, to receive instructions and send back aerial photos. So as long as it stays within range, it might operate for months.
The Futurism article includes a video simulation of Ingenuity in action.
This will be the first time that an aircraft has been flown on another world, and the potential is enormous
The vehicle has to be small and light, it will operate in an atmosphere that is 0.6% as dense as ours. but a similar type of vehicle, deployed, say, in the Venusian atmosphere, or Titan, one of the moons of Jupiter, could be much larger, and fly for months without stopping.
So SpaceX has conducted its first flight test of its next gen passenger capsule, StarShip, which will be able to carry up to 100 people at a time when it goes into operation.
They flew it 150m into the air, then extruded landing struts and landed it.
But what, precisely, were they testing? It was unmanned and looked like pretty much just the shell of the vehicle
Deploying legs and landing? Done that before. The engines? It used one Raptor engine, which is already being used in live missions. This test used just one engine, when the final vehicle will use six together
The second flight of Space X ‘s Falcon Heavy rocket took off earlier today and looks to have been a complete success .
It delivered it’s Arabsat payload to orbit then landed all three of it’s boosters safely back to the ground.
Seeing the footage still gives me a thrill. Such a massive vehicle , such an amazing feet to land the side boosters together, side by side. It reminds me ot my childhood, like a scene out of Thunderbirds
We spent last weekend in Lyme Regis. Cold weather for walking, but fantastic restaurants and coffee shops.
We were also lucky enough to come across a wonderful art gallery run by Richard Bizley. Richard has a really vivid imagination, his paintings cover all sorts of atronomy and space themes. I particularly liked the ones focused on what life could really evolve as in differing types of planetary environments. We bought a picture that reminded me of the film Avatar, though the picture predated it.
In the modern world, most things are driven by economics. If something can make money, especially if its a lot of money, someone will make it happen.
And so it is with space exploration and colonization. The commercial opportunities are the most often quoted reason why humanity’s expansion into space is inevitable.
Think of all that space, that real estate, available on the Moon, the asteroids and on Mars. And all those resources buried under the surface.
The most often quoted precedent for mass colonisation of “new lands” is the settling of North America. America had vast empty spaces, huge supplies of coal, metal, timber and wild animals to support the countries development, and few local natives to hinder their expansion. The settlement of the country by the Europeans and its development over the next few centuries lead to the emergence of the greatest single industrial power in history.
So who’s to say it can’t happen again on, say, Mars?
A Martian colony would need support from Earth for generations
Well, there are differences. In the Americas the new colonists could fairly soon live off the land, with food and lumber readily available. Mars will be dependent on Earth for generations for food in the short term, but in also the long term for complex tool and medicines, and minerals and metals that aren’t readily available on Mars.
America was able to export tobacco and grain back to Europe from fairly early on, giving a financial return to those who had paid for the transporting of the colonists. Mars will have nothing to offer that couldn’t be more cheaply and easily produced on Earth. The cost of sending metals mined on another planet home, for example, would be staggering (the one possible exception to this might be mining Helium 3 on the Moon. This is a isotope of Helium that would be essential to Fusion power plants, if we can ever get this amazing new form of power production working. There’s very little Helium 3 to be found on the Earth, but much more of it is on the surface of the Moon).
Some people argue that the divergence of cultures between Mars and Earth will throw up new and saleable cultural, artistic and technical innovations. This is a long shot. There is no precedent for this on Earth. Even for America the rate of technical innovation was due to the growing huge industrial base, not because of its geographical distance from Europe.
Colonizing Mars, or the Moon, will not be driven by profit from mining or industry.
Mining the asteroids is another oft quoted source of potential massive profits from space expansion. Companies like Planetary Resources and Deep Space Industries suggest there are trillions of dollars worth of rare metals in asteroids circling the sun in near Earth orbits, and certainly the prospects are exciting. But the technological challenges and cost of mining asteroids and bringing the results back to Earth shouldn’t be underestimated.
Planetary Resources proposed method of asteroid mining
But even if mining off planet were profitable, would it require a permanent space colony with thousands of colonists? All of this activity must surely be possible using just a few hardy engineers commanding an army of semi-autonomous robotic miners.
It’s been suggested that in the future mass industry will be developed in Earth orbit, to take advantage of the space available, the zero gravity environment, and imported metals mined from the asteroid belt.
This I just can’t see. If more room is needed for industry, there’s plenty on earth that’s more hospitable; even factories floating on the surface or under the sea would be easier to build and to service.
The only likely advantages of industry in zero gravity would be for producing specialist crystals and possible 3D printing human organs. We wouldn’t need massive orbital factories for these, and in any case, the bigger the space station the more they would generate more vibrations in their structures and defeat their own purposes.
Space tourism has some limited scope for feeding the expansion of the human kind. People will want to visit hotels in Earth orbit and travel to the moon once these things are possible, and even visit other places if the travel time were to be brought down from months to weeks. I could see the growth of a limited market here. But would the growth of America really have taken off if people just traveled across the Atlantic Ocean for three months, stayed for a fortnight, and had to come straight back again? Probably not.
So I’m sad to say, I don’t see the business case stacking up for any of these scenarios. If colonisation of the solar system is to happen, the profit motive will not be the main driver for it.
Will the Human Race fulfill its destiny, and move out from this small blue planet and colonise other places in the solar system, and one day even travel to the stars?
I, and many other supporters of space exploration, and even fans of Star Wars and Star Trek and the like, would certainly hope that it will happen. Surely, it’s inevitable. Humanity has always been a race of explorers and colonists, filling every corner available on our own planet. It’s only a logical progression that we will one day move out and colonise the other planets and moons available nearby.
Well, I got to thinking, “Surely” and £2.00 will get you a cup of tea. “Surely”, on its own, is just another word for “Hope”
It would be interesting to take a look at our real prospects for the future of human space exploration and long-term settlement of the solar system. And to do that, we must look at the different potential drivers for doing so, and how they might shape this enterprise. After all, becoming a multi-planet species is going to be the most expensive thing we’ve ever done.
We will look at the following drivers
Scientific Research
Commercial Gain
International Competition
Prestige Projects
The Merchant Princes
Scientific Research
Since the start of the 1970’s, scientific exploration of space, the solar system and of human kind’s ability to live in the harsh space environment have been the primary focuses of space exploration activity.
Robots and space probes have visited most of the planets and landed on the more accessible ones, dwarf planets, comets and asteroids have been visited, and probes sent to investigate our sun.
We’ve learnt a lot about our cosmic neighbourhood, and there’s undoubtedly more to learn. During this time, however, the scope of human space exploration, humans actually going to new places and “placing boots on ground”, has actually shrunk. Since the end of the Apollo era, since 1972 when the last astronauts visited the moon, we have never sent a single person out of Earth orbit.
Why is this?
Sending people into space, let alone to other planets, is much more difficult than sending robots. A human mission to Mars, for example, would probably need a minimum crew of six (they’d need a variety of people to be able to mix with, if they’re going to be locked in a tin can for three years).
They would need to take all their air, food and water with them, which even allowing for some limited recycling, would be a significant weight. And they’d most likely want to come home afterwards, which means taking all their fuel for the return trip with them as well.
All of this would need a spaceship of a hundred tons at a minimum. A robotic probe needs none of the above and can weigh less than a ton.
All of this means that a crewed mission will always cost several orders of magnitude more than a robotic one.
Any endeavor is going to be extremely costly, for example, this would be my best guess at a price list for missions to Mars:
Sending a one-off crew to stay a few months and come back
$100 Billion
Building a base where the crew can have more room, and more varied science can be carried out
$300 Billion
Building a permanent settlement, where people can go, live, and have children
$1 Trillion
In comparison, NASA’s Mars Curiosity Rover cost around $2.5 Billion, expensive for a robotic probe, but cheap compared to a human mission.
NASA always claims that the reason to send people away from Earth is because they are better at searching and carrying our experiments than robots are. On Mars, they’re specifically talking about looking for signs of life, whether currently living bacteria or fossils of bacteria that were alive in the distant past.
But they’ve been talking about sending astronauts to Mars for the last fifty years, and still aren’t close to doing so. It’s too expensive and too risky.
Science, on its own, can be done by robotic probe. Science, on its own, won’t be a reason to send humans anywhere!
Next Blog: Commercial Gain as a driver for Human Space Exploration
Most space geeks would like to believe that all of the difficulties in interplanetary travel are to do with technology, and once you’ve cracked that, all you have to do is jump in your rocket ship and go.
The reality, unfortunately, is a little different. Hardware might be difficult, but human beings are frail and the solutions to their issues can be much more complex and challenging.
A lot of the reason why NASA has been parked in orbit in the ISS for the last twenty years is to research the human factors issues that a journey to Mars would present (okay, the ISS is a lot cheaper that Mars, as well).
At NASA’s request, the US National Academies of Sciences, Engineering and Medicine have just completed and published their latest review of NASA’s research in this area.
Astronauts exercising on the ISS to mitigate bone and muscle loss
The report covers the areas you’d expect, physical impacts like muscle and bone loss, radiation damage and permanent damage to eyesite. It also looks at psychological impacts of living for long periods in a confined space, with only the same, few people to interact with, with no real time communications possible with family and friends back home.
These issues can only multiply when put together; if you’re having morale problems on the trip anyway, try throwing in having problems with eyesite and circulation.
Transorbital 