Colonizing Mars - PowerPoint Presentation

Slide1

Colonizing Mars

Dr. Dale Partin and David Bailey March, 2017

Elon Musk’s vision for an Interplanetary Transportation System. Passengers are boarding for a trip to Mars.

http://www.space.com/34210-elon-musk-unveils-spacex-mars-colony-ship.htmlSlide2

Outline 

Why colonize?Human Health in SpaceMarsStages of Colonization of Mars

https://www.youtube.com/watch?v=SGbY6MaEp4k

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Why Colonize Mars? 

Because it’s thereSurvival of humanityScientific researchMore places for people to liveMake money

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Chicxulub impact visualizedSlide4

Astronaut Health in Space 

Beyond funding, the largest problem that needs to be studied to get humans to Mars is human health issues.WeightlessnessRadiation

Micrometeorites, Accidents

Psychological stress

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Effects of Long Term Weightlessness 

Muscle atrophyDeterioration of the skeleton Slowing of cardiovascular system functions Decreased production of red blood cells Balance disorders

Vison changesWeakening of the immune

system Loss of body

mass

Sleep disturbance

Excess flatulence

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Muscular atrophy

Bone loss

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“Fixing” Weightlessness 

Rotating the spacecraft on a tether connected to a booster rocket stage to create artificial gravity may be needed.7Slide8

Radiation Exposure in Space 

Based on calculations of radiation exposure during a 3 year round trip to Mars, as many as 5% of astronauts may die from radiation. This includes 6 months to get there, 6 months to get back, and 2 years on Mars. Negative effects include cancer, cataracts, brain damage, and death.

Mitigation strategies include shielding and drugs. Neither one seems practical now.

A major solar eruption could cause enough radiation exposure to be lethal within hours if not adequately shielded.

Travel to Mars is dangerous… Once there, colonists will need to mostly stay underground.

https://en.wikipedia.org/wiki/Health_threat_from_cosmic_rays

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SpaceX Approach 

An alternative approach to mitigating both the effects of weightlessness and radiation exposure in space is to get to Mars much faster. If the transit time to Mars could be reduced, for example, to 2 or 3 months, then both of these problems would be partly fixed. This would require a new, more powerful propulsion system, such as the SpaceX ITS rocket, now in development. 9http://www.space.com/34210-elon-musk-unveils-spacex-mars-colony-ship.htmlFuture SpaceX ITS rocketSlide10

SpaceX Approach  

Elon Musk plans to put as many as 1000 spacecraft in orbit around the Earth, each with 100 people on board. These ships would wait until the right “launch window” to Mars each 26 months, and then all head for Mars together. This would mean a very long time exposed to weightlessness and radiation while in low Earth orbit. Oxygen and methane would be manufactured on Mars for the return flight.10http://www.space.com/34210-elon-musk-unveils-spacex-mars-colony-ship.htmlFuture SpaceX ITS rocketSlide11

An Alternative Approach? 

11Alternatively, an asteroid or Near Earth Object could be hollowed out to provide interior living space, with protection from cosmic rays. It is rotated to provide 1 g of “gravity”. There is a spaceport on one end and an ion drive on the other. spacecraft

A habitat under construction

See science fiction novels by Kim Stanley Robinson

Or see:

http://www.orbitbooks.net/2312

/Slide12

12Example: Artificial Gravity Inside an Asteroid

For a rotating object,The acceleration is a = V2

/r

The velocity is then V = (

ar

)

0.5

=

(gr)

0.5

For 1 g of artificial gravity, a = g

= 9.8 m/sec

2

.

For an asteroid with a diameter of 1 km, r = 500 m. Then, V = 70 meters/sec. This means that the asteroid would need to rotate once every 45 seconds to give 1 g of “gravity”.Slide13

13Asteroid Ship Issues

Some of these objects are a loosely bound collection of rubble that would disintegrate if

spun. Particles that are flung off would contaminate space

. Also, if the object is very irregularly shaped, it might tumble in space.

It may be regarded not as a ship, but as a destination – a home.Slide14

14Circular Space Ship

Finally, one could make a circular space ship that could be rotated up to 1 g. The walls could be 2 meters thick to stop most radiation. The ship could stay in Earth orbit, housing people until they are ready to board rockets to go to Mars via a fast rocket. Or, the circular space ship itself could go to Mars using large ion drive engines.Slide15

Potential Solar System Habitats

GOOD

NEUTRAL

BAD

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Potential Solar System Habitats: the Moon

The easiest place to get to. No hope of terraforming the surface – too little gravity to hold an atmosphere. Living underground would be necessary to provide shelter from cosmic rays. Water present at the poles in craters.Very low gravity likely means that humans would need to spend much of their time in a centrifuge to simulate 1 g.

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Potential Solar System Habitats: the Moon

Schackleton Crater near Moon’s south pole. ESA is considering this area for its Moon base. There is sunlight on the crater edges 80-90% of the time. It is 21 km in diameter and 4.2 km deep, with frozen ice at the bottom. Earth is visible half of the time from the top of the rim.

http://www.dailymail.co.uk/sciencetech/article-4162296/The-incredible-lunar-TEMPLE.html

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Potential Solar System Habitats: the Moon

The European Space Agency

plans to build a village on the moon (concept pictured

). This is

part of a much wider scheme to explore the far-flung regions of our solar system. Speaking at a recent conference,

ESA

boss Jan

Woerner

said: 'I think we should go first to the moon and then further on'

http://www.dailymail.co.uk/sciencetech/article-4162296/The-incredible-lunar-TEMPLE.html

The surfaces of this habitat would need to have thick enough surfaces to stop most cosmic rays.

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Living on the Moon – in a Centrifuge?

NASA centrifuge that can go up to 30 g to test spacecraft parts, or whole spacecraft

The effective force of a centrifuge is

F = (mV2

)/r = ma

Where m is the mass of a test object, V is the speed and r is the radius

The acceleration is then

a = V

2

/r

For example, to get 1 g of acceleration if r = 20 meters, V = 14 m/s = 31 mph

This would mean 9 seconds per revolution, or about 7 RPM

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A Centrifuge on the Moon

(top view) (side view)

Low lunar gravity and cosmic rays may mean that humans would always need to spend part of their time in an underground centrifuge to simulate 1 g.

Cosmic rays

person

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Potential Solar System Habitats:

MarsRaw Mars is lethal: freezing temperatures, unbreathable atmosphere, low gravity, cosmic rays on surface, no rivers,

no food, toxic soil…

Mars is a long way from Earth, but reachable. Living

underground would be necessary to provide shelter from cosmic rays.

Lots of water ice is

present

just under the surface

. There is a long term hope of terraforming the surface.

The surface gravity of 0.4 g

may

mean

that humans would

need

to spend

much

of their time in a centrifuge to simulate 1 g

.

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Energy Sources on Mars

Wind energy not viable – Martian atmosphere is very thin (1% of pressure on Earth)Solar energy somewhat viable. Sunlight on Mars is only 43% as bright as on Earth, so use of a solar concentrator

is preferred. The Martian day is 24 hours and 40 minutes long, so the day/night cycle is similar to that on Earth.Solar cells to generate electricity.

Solar thermal power to generate heat energy.

Nuclear power is much more dependable and thus is preferred. The waste heat could be used to circulate warm water to living quarters, plant farms, etc.

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Solar cells for electricity

Solar thermal for heatSlide23

Energy Sources on Mars

A problem with solar energy is that there can be prolonged dust storms – weeks to months. This would block sunlight, and coat the solar cells with dust. Nuclear power is much more dependable. Better have a back-up energy source in case of a reactor problem…A planet-wide dust storm on Mars can last for weeks or months23Slide24

2. Raising Food on Mars

on the surface:

using

pressurized, breathable air

inside

triple-paned greenhouses

solar reflectors / concentrators

cosmic rays

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Use warm water radiators or electric heat to keep crops from freezing during Martian night or sandstorm

Use high efficiency electric lights to supplement sunlight during sandstorm. Use controlled atmosphere inside at elevated pressure to be optimum for plants and people. No need for space suits inside. Greenhouse construction needs to be strong enough to withstand pressure differential.Raising Food on Mars – on the Surface with pressurized, breathable atmosphere inside

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Scenes from “The Martian”Slide26

Will need to periodically clean Martian dust off of glass and reflectors.Grow seed crops underground to prevent build-up of genetic damage from cosmic rays to protect future generations of crops.

Alternatively, could try to grow plants in the ambient Martian atmosphere. However, the pressure is so low (around 6 mbar, depending on altitude) that water immediately vaporizes. This would dehydrate the plants. Some plant cells would burst at such low pressure. The Martian atmosphere contains CO2, but plants also need oxygen when it is dark. Also, farm workers would always have to wear space suits.

Raising Food on Mars – on the Surface

with pressurized, breathable atmosphere inside

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Farms in old bomb shelter under South London. Doing this underground on Mars would offer a stable, protected environment free of cosmic ray damage.

Raising Food on Mars – Underground With pressurized, breathable atmosphere inside https://www.fastcoexist.com/3051209/this-london-underground-farm-grows-salad-in-a-wwii-bomb-shelter/3

27http://www.ibtimes.co.uk/inside-uks-first-underground-farm-photos-old-air-raid-shelter-now-used-sustainable-growing-1588187Slide28

Engineer Martian soil so crops will grow in it. Remove toxic perchlorates.

Raising Food on Mars – Research Issues28https://www.researchgate.net/publication/242525435_Perchlorate_on_Mars_A_chemical_hazard_and_a_resource_for_humansSlide29

Find out whether 0.4 g is enough gravity to keep humans healthy. Use a centrifuge inside the International Space Station for mice. They could be studied at 0.16 g (Moon) and 0.38 g (Mars). Studies like this have so far been vetoed.

Studies of mice at 0 g on the ISS already show strong health effects similar to humans: Data revealed loss in weight-bearing bones, muscle atrophy, etc.

Human Health on Mars – Research Issues

https://www.nasa.gov/mission_pages/station/research/experiments/665.html29

Interior of Japanese centrifuge for mice, intended for ISS.

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0133981Slide30

G-Lab is a proposed system to have a lab with rotating space inside to test astronauts or other vertebrates under reduced g. It would fly near (~ 10 km) the ISS.

Human Health Research Issues30http://ssi.org/ssi-update-april-2012-introduction-to-g-lab/Slide31

Stages of Colonizing Mars

Getting people into Earth orbit 1961Going to the Moon for a 2 day visit 1969Establish a permanent base on the Moon

2030?

Going to Mars for a 2 year visit (4 people) 2035?

Establish a permanent colony on Mars (100 people) 2060?

Martian colony becomes self-sustaining (100,000 people) 2120?

Begin terraforming Mars? (1,000,000 people) 2200?

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Many Countries Are Interested in Colonizing Mars

The United Arab Emirates (UAE) have announced plans to colonize Mars. The aim is contained in a statement titled the “Mars 2117 Project” which at its final stage involves building the first habitable human settlement on the red planet by 2117. (Feb 15, 2017)http://www.breitbart.com/jerusalem/2017/02/15/space-invaders-united-arab-emirates-plans-colony-mars/

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Martians - a New Human Species?

It may be that humans cannot naturally adapt to Martian gravity (0.4 g). This might mean that they will have to spend part of each day in a centrifuge. Perhaps running the centrifuge at 1 g (or ~ 1.5 g) would decrease the fraction of time required to be spent in a centrifuge. But long term, this is undesirable. This problem might require genetically re-engineering humans, changing our DNA so that we are optimized for 0.4 g. We might then be, to some extent, a new human species or ethnic group – Martians!

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A Martian?Slide34

Fixing the radiation problem on Mars

The next problem would be to have a defense against cosmic rays, to permit life on the Martian surface. This requires a thicker atmosphere…34

Aurora – high energy particles being blocked by the Earth’s atmosphere before they make it to the surface.Slide35

Terraforming Mars

Warm the planet by focusing sunlight on it.35

Reflector at Lagrange L1 point.Get material for it from Mars’ moons

A reflector could be put “behind” the planet at L2.

Sunlight

Need to set up factories on Mars to process rock into greenhouse gases. These gases should have high molecular weights like CO

2

so they do not escape from the planet. This would not be breathable but might eventually allow plant growth on the surface. It would also give protection from cosmic rays at lower altitudes.Slide36

Terraforming Mars

Decrease the albedo of Mars36

Sunlight

Another way to warm Mars is to decrease its albedo, or reflectivity of sunlight. The albedo of Mars is already pretty low at 0.15. The albedo of some other bodies are Earth (0.37), Venus (0.65) and the Moon (0.12). These are planetary averages. One could get the best effect on Mars by working on the brightest places and make them darker.

F

orests on Earth have an albedo of 0.04 to 0.1, depending on the type of trees.

http://www.asterism.org/tutorials/tut26-1.htmSlide37

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Elevation Map of MarsHellas

Planitia(12 mbar, 2300 km diameter, 7 km deep)

Utopia Planitia (6 mbar)

Olympus Mons (0.3 mbar)

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Mars: Some Issues

The cost of all of this colonizing will be large. Private industry is best at getting the costs down. SpaceX, Blue Origin, the United Launch Alliance, etc. are to be encouraged. Life support / recycling / live off the land studies are needed.Repurpose the ISS to study Mars issues?

Go to the Moon first to get experience.High risks to personnel will have to be accepted. Some will die.

SpaceX

ITS taking off

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Mars and the Moon: Let’s Go!

We choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard; because 

that goal will serve to organize and measure the best of our energies and skills, because that challenge

 is one that we are willing to accept, one we are unwilling to postpone, and 

one we intend to win

... JFK

Blue Origin’s New Glenn (in development)

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