Chris Hadfield does not think those rockets are a practical way to send people to Mars because they’re dangerous and it takes too long.
Chris now has a 28 lesson online Masterclass course on Space Exploration with a 29th bonus chapter.
Lesson 7 Rockets: Fuels and Propulsion
Chris explains the pros and cons of different types of rocket fuels including liquid fuel, solid fuel, and ionized gas.
Lesson 24 Mars: How to Get to Mars
Chris explains the technical and societal challenges we face in traveling to Mars, including the ideal flight path required, the physics of slowing down and landing, and the risk of human life.
Chris talked about the corrosion problem with water when he was on the Mir space station.
Nextbigfuture disagrees with Chris Hadfield and believes the SpaceX BFR can be used to colonize earth orbit, the moon and Mars
The SpaceX BFR rocket could achieve 40-50 day trips to Mars by using faster Parabolic transfer orbits. A future 200MW powered Vasimr would only be able to have 10-20% faster trips to Mars than a SpaceX BFR. We do not have a 200 MW reactor.
I am not sure how much Chris Hadfield has made an effort to scope out what is an acceptable Mars mission.
An orbital refueling of the SpaceX BFR at a high orbit to maximize the speed of the BFR to send one that is fully fueled would shorten the trip down to as little as 40 days.
Space Missions to Mars up to now have been small satellites where the entire mission was launched from Earth. The delta-V has been about 3.2 to 3.5 kilometers per second.
By refueling the SpaceX BFR in orbit and assembling a few stages in high orbit, a large chemically powered space mission can get up around 9.0 kilometer per second delta-V.
We will not need to wait decades for super-advanced space propulsion to be developed for less than 60-day trips to Mars. Elon Musk and SpaceX should have the BFR flying within 5 years.
Short 45-60 day or even 30-day trip using large multi-stage chemical rockets launched from high orbits after refueling will make large fast missions easy. The shorter times mean far less radiation and health issues for astronauts and passengers. The far larger ships means water and other material for radiation shielding.
Bigger and more powerful spaceship will be like cruise ship versus dingy
The Mars missions we have sent have been less than 1000 kilograms but putting a few BFR payloads together could send 1000-ton Mars missions.
SpaceX is bringing the next BIG future in space.
In World War 2, after D-Day there was 8,500 tons per day of cargo being sent to the beaches. Fifty SpaceX BFR would be able to regularly shuttle that amount of material to orbit. We will be able to invade space (moon, orbits, lagrange points, Mars) the way Europe was invaded by the allies.
Power starved up to now
The low power and delta-V budgets have forced space mission planners to use slower hohmann transfers. Those are the most economical but are long circular orbits that look more like orbits around the sun than targeting a flight to Mars.
Elliptical and parabolic orbits have less curve and are much shorter and much faster trips.
Earth-Moon Lagrange 2 or EML2 is one of 5 locations where earth’s gravity, moon’s gravity and centrifugal forces all cancel out. It lies beyond the far side of the moon at about 7/6 of a lunar distance from earth.
EML2 would make a great transportation hub. Not only for travel to destinations throughout the solar system but also within our own earth moon neighborhood.
The SpaceX BFR will be fully reusable and able to carry 150 tons for Earth to Low Earth Orbit but it could refly once to seven times per week. So a lot of refueling missions and taking large pieces of space stations and moving large payloads between low earth orbit, high orbits, moon and lagrange points will be easy.
Place Multiple Bigelow Hercules resupply depots at each Lagrange point, various Earth orbits, lunar orbit and Mars Orbits
Nextbigfuture has described how very large rotating space stations around the earths equator could be made to provide radiation safe living with full one gravity equivalent from rotation.
This would be safe be part of a safer path to space development.
* Build many SpaceX BFRs
* Build massive orbiting space stations around the equator that provide radiation safety and one full gravity equivalent. With a few SpaceX BFRs able to launch many times per week, 150 tons per launch, a massive space station of tens of thousands of tons could be built in 1-2 years. A key would be a fast assembling system for connecting large 50-100 ton earth built modules in space
* Make larger lunar bases Joseph Friedlander described part of using the BFR to make lunar bases here at Nextbigfuture
Robert Zubrin has described better plans for lunar and Mars colonization.
* SpaceX BFR could assemble Mars transportation where multiple SpaceX BFS are connected and set up to rotate to provide the equivalent of gravity during a mission to Mars. The larger loads and reusability of the BFR could be used to assemble larger systems for providing some radiation protection.
* Going to the surface of Mars would require that colonist to live with lower gravity. Rotating one G equivalent stations could be placed in orbit around Mars and the Moon so that colonists of the Mars and Moon could go to one-G locations every so often to counter the lower gravity of the Moon and Mars.
Mars ISRU is being developed
After landing on Mars, Sabatier reactors would be used to gradually refuel each Big Fucking Spaceship. The Sabatier process follows the laws of thermodynamics and thus requires a power source to heat the inputs, as well as cool the outputted methane and oxygen into fuel-grade cryo-cooled liquids. NASA is working on KiloPower and Megapower nuclear reactors. SpaceX could also bring large amounts of solar panels. Solar would half as energy dense on Mars but we could bring a lot more panels in a BFR.
Written by Brian Wang, Nextbigfuture.com