Power is everything is a famous quote from the movie Apollo 13. A similar statement is made by Marc Millis about interstellar travel. Marc is a thought leader in interstellar travel. Marc says that for whatever speed increase we want then we will need to square the energy increase.
If we want to go ten times faster then, in general, we need 100 times the energy for the propulsion.
I have observed that SpaceX has been doubling its annual launch capacity every two years since 2009. This rate of progress will soon be doubling or more every year with the fully reusable Superheavy Starship.
Each Starship also has more volume than the International Space Station. Each Starship will enable a large base wherever they are kept in orbit, the moon, Mars or elsewhere.
This also means we can bring gigawatts of solar panels, batteries and arrays of modular lasers.
Ten gigawatts for laser arrays to push vehicles would enable rapid acceleration and transit times of 2 to 6 days between earth and Mars. We would arrays of lasers and power systems for them to accelerate sails from Earth to Mars and to decelerate them as they arrived.
SOURCES- NASA NIAC, Marc Millis, ITW, Apollo 13
Written by Brian Wang, Nextbigfuture.com
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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Well, we would disband the Senate and let the Governors rule their territories with fear
On the other hand, diffusion is a thing.
On the Gripping Hand, however…..
Those solar arrays would fly away from a Lagrange position, what with pressure from light and the solar wind.
It has been suggested to take a leeward position short of the L2 of a planet, adjust trim sails to balance against combined solar and planetary gravity, thus taking advantage of thrust generated from solar exposure effects.
This provides a possible station keeping option. The array is not in orbit of the planet. It is not in true orbit of the sun either. It is gravitationally tethered in synchrony to the planets motion.
You get gravity for free upfront rather than having to make your gravity.
Mars is where you get water/hydrogen/carbon/nitrogen apart from Earth’s expensive gravity well before you make it out to Ceres.
Being on Mars isn’t like being on Earth. It is trivially easy to make a reusable SSTO rocket to get to and from Mars orbit. So easy that Mars will be a good exporter of bulk materials (N,H,C, etc).
The ABL had a MW laser two decades ago mounted in a plane. We aren’t struggling with 100kW lasers.
Don’t worry the Moties are a peaceful race.
Considering the ease of deploying mirrors in orbit, and the ease of focusing sunlight with those mirrors, it seems to me optically pumped lasers are the way to go. Who cares if conversion efficiencies are lower than diodes, when sunlight is free?
Acccording to a white paper linked below, conversion efficiency would be similar to that of PV-laser diode hardware.
The earth-luna Lagrange points are fairly free or orbital debris, and would be the perfect place for optically pumped lasers as large as you care to imagine. Waste heat removal from the lasing medium is likely the only serious constraint on the power of a continuous beam.
Here is a link to a paper that states 20% efficiency from sunlight to beam power can be achieved at the time of publishing(2014).
file:///C:/Users/marty/Downloads/Solar-pumped-laser-white_paper.pdf
Not much momentum available for transfer single bounce with the Gw laser—enough to levitate the mass of a squirrel in Earth’s gravity per memory. If the reflectance is optimized for monochromatic light, one might set up multiple pass bounces between a ship and a much larger mass holding a partner retro-reflector. This will provide more return on investment of the energy applied to beam generation. TANSTAAFL
I’m not convinced we can dominate all this Multi-Gw laser ship thing by 2040 either. Not only about the politics of it, but the actual science and technology (point a Gw laser at anything and you usually vaporize it, specially gossamer thin light sails ).
I do think we can have very interesting capabilities by then, like many passenger carrying Starships taking people to the Moon and Mars, maybe to a few other places up to the asteroid belt (I’m an optimist!).
Also a lot more economic activity, many more facilities in orbit, asteroid mining drones, SPSs and crewed facilities, including some early rotating habitats, born from the ability of launching a few million tons more per year.
Gee, even a few nuclear spaceships could be made by then, to take scientific cargo to far away places relatively soon. Nuclear spaceships will bloom later, on the second half of the XXIth century, when people living in space is no longer a novelty and there is a commercial need for them.
But by 2040, trips for people most likely will continue being a matter of weeks and months, not going that far either (from Earth to orbit, the Moon and Mars or from Mars up to the asteroid belt).
I think I can believe, ‘Interplanetary as easy as intercontinental was in 1600’.
Anyone who complains about it taking months to get to Mars lacks historical perspective. For a few centuries after 1500 people were taking months to travel around Africa from Europe to Asia, or paddling from Montreal to Fort Edmonton for fur trading. Steamships & railways cutting the travel time later was nice, but the slower stuff was needed to get to the point that the steamships & railways could be built.
Funny that we are still struggling with 100 KW lasers after so many years and we don’t know how to beam lasers for long period of time on thin sails without burning them. Few things here simply just defy 3rd grade multiplications…
Who is in charge of this 10 gigawatt laser? It would also make a pretty lethal weapon.
I’m mostly with you, but it doesn’t need to be sold on Earth to make a profit.
So, if someone can produce something that can be sold to Asteroid miners, or even in Earth Orbit, that would still be (possibly) viable.
delta V to get from Mars surface to GEO is (from what I can make of the wikipedia tables) about the same as Earth to GEO.
Your remarks capture my view. Of course there will be space habitats. Kim Stanley Robinson’s 2312 is fully populated with giant spinning cylinders. But people like territory, private property, open ended opportunity, and especially big ambitious goals. Yes, you can always create a new habitat. However, creating a civilization on Mars is a whole different level of goal, vision and purpose.
Mars settlement is Musk’s pet project. He will pay it from his pocket if he has to. And yep, Mars won’t be producing tangible goods for Earth except expensive souvenirs.
But it will produce intangible ones. Like science and technology. Or entertainment.
Or even a sense of community, accomplishment and adventure for some people. Reasons more than enough for some people to pay for them.
But I wasn’t speaking only about Mars: LEO, MEO, cislunar and lunar space have plenty of untapped opportunities for business, given they are much closer to Earth.
Even free floating space has such opportunities. The road only has to be open for less money.
Please see Al Globus papers at nss dot org. No shielding required, and 1 g easier than thought at small size. Good news!
They will go to O’Neill Space for these things. Not so avail on planetary surfaces. Certainly not those we are not already on.
If you assume you are going to live on planets in the future, you are stuck!
Please see:
http://www.searchanddiscovery.com/pdfz/documents/2009/70070criswell/ndx_criswell.pdf.html
“On the other hand, real estate is in limited supply. I don’t see living in fragile, expensive, difficult to supply space habitats when you can go live in gravity with an infinite supply of raw materials”
Have you read “The High Frontier”, by G. K. O’Neill?
I don’t see the money part. Ask yourself this question, what will be produced on Mars & sold for a profit on Earth?
You can have any gravity you want in space. Plus 5 times the solar power available (at Earth’s orbit) than on the surface of Mars. Resources are more easily discovered and more available. The only advantage for Mars is the opportunity of digging a hole in the ground to avoid radiation. The center of a moderately sized rock in space or an O’Neill habitat w/some shielding orbiting inside the Van Allen belts can match that advantage.
I don’t think we’ll be going into space just to go back down another gravity well. I’d wager that anything built on Mars will cost 10 times what it would cost for the same thing in LEO.
Yeah, nobody is going because they have to. Earth isn’t full and probably never will be (I mean really? how many people we need to fill the surface of the Earth?). People will be going to space because they can.
For adventure, to flaunt their money or for work, whatever. The real difference is being able to go instead of not being able, as is the case today.
Also you noticed that most places on Earth are empty and devoid of interest, even if they are like 1000x times better than the best spot of the Moon or Mars.
So, why going to these offworld wastelands?
Because rich, highly dense loci of human activity with plenty of work, attractions and opportunities for status are few and far between, and spots on them are highly desired. Humans look for those things: wealth, status and a bit of adventure.
Therefore, people will seek to go to the Moon and Mars: because these places will be born from wealth & power, and people will go there to gain fame and glory. And money.
About 750,000 sq. miles of land in the US is too unproductive to even support cattle grazing. This is shrubland.
NYC is 26,000 people per square mile. Worthless shrubland in the US could host 20 billion people at this population density.
Converting this land into high population density cities would be really hard, but definitely possible with technology available today. Doing the same on Mars would be MANY MANY orders of magnitude harder, if not impossible.
NOBODY will move to Mars on account of the Earth running out of real estate.
This has all got to be about real estate on Mars. I just don’t see other human needs that will translate into the capital required to build the fully imagined SpaceX fleet.
On the other hand, real estate is in limited supply.
I don’t see living in fragile, expensive, difficult to supply space habitats when you can go live in gravity with an infinite supply of raw materials (but maybe space habitats after Mars.)
Who is going to control real estate, e.g. land use rights, on Mars?
Kim Stanley Robinson’s “Mars Trilogy” is looking more prescient all the time.
We could also be smart and launch ISRU equipment, otherwise we are already short of things to launch, compared to Space.