NASA NASA: We're sending humans to Mars

[marcus]

Dawn's distance to Ceres now 900,000 km
More exactly
.006035 Astronomical Units = 902 823.15 kilometers
according to the current fulltraj update.
http://neo.jpl.nasa.gov/orbits/fulltraj.jpg

I'll check the mission director's blog ("Dawn Journal") to see if he has anything new:
http://dawnblog.jpl.nasa.gov/2014/
No, this 28 November entry is still the latest
http://dawnblog.jpl.nasa.gov/2014/11/28/dawn-journal-november-28/#more-1533

Ceres data:
http://en.wikipedia.org/wiki/Ceres_(dwarf_planet)

 

[Monsterboy]

Thanks for the links! 3 kilometers sources good!
You are right about under-ice experimentation. Pressurize to test for air retention. Measure factors involved in stability: stalactite growth, differential melt and freeze, structural strength and reliability, air-lock design for connection with surface, power plant operation with in-cave cooling. small nuclear power units as in submarines. Artificial light in the cave, to grow food. I haven't heard of any Antarctic experiments like that. Why don't you write a letter to someone in NASA?

This has not been done probably because NASA currently has no plans to build bases on Mars.
I don't know anyone in NASA ,perhaps some people in PF actually work in NASA ??

I agree, a rover should land on one of the poles and check it out! this would be so fine! I don't understand why they have not done it already, the polar icecaps are the most interesting parts of Mars, in the long run.

There was one attempt to land near the poles (Mars polar lander) ,it failed because it crash landed! ,i too don't understand why the polar ice caps remain unexplored ,perhaps there is some technical difficulty in landing something over the poles ?
If we land people on Mars ,it will mostly probably be near the poles right? radiation levels will be lower there and water will be available in the required quantity right?
If we ever find life on Mars ,that too is mostly likely to happen in the polar regions ,since several metres deep water ice can reduce radiation levels to that of Earth's hence photosynthetic life might be possible within the ice layers of the polar regions.

 

[Monsterboy]

http://astrobiology.nasa.gov/articles/2014/5/15/destroying-glycine-in-ice/
Now some astrobiologists say even under ice ,life is difficult to be sustained on Mars but the article doesn't mention depth of water ice required to sustain life.

 

[marcus]

It's really two questions. They were talking about photosynthetic life. that has to be near enough the surface of the ice to get light. So there is no question of going deep enough to be safe from radiolysis of glycine. Those are issues about the possibility of life emerging and evolving independently on Mars long ago, and issues about the preservation of traces of life, in the ice, from which we could learn about prior history.

But clearly those research issues do not affect the practicality of operating a base safely under Mars ice caps, only (indirectly) one of the motivations for doing so.

Thanks for the interesting links! I think you are right about all the points you made. I still suspect it would be more interesting to establish a human settlement on Ceres. Partly because there's expected to be a lot MORE ice---deeper and planet-wide---so room to expand and a good way to cool thermodynamic power cycles, if our species learns to thrive in 3% gravity. More place to go if you're successful.
Partly because the gravity is so weak it would be easier to land and take off.
Partly because IF our species ever finds reason to utilize or settle more parts of the solar system, Ceres could provide WATER MORE CHEAPLY than the Earth could. Water for life and industrial processes, hydrogen and oxygen for propulsion. So there is a long-range reason to want to utilize (if not actually settle on) Ceres.

We won't actually know much for sure about the place until the Dawn craft arrives in March 2015. So I'm just speculating. But it seems likely to be a ball largely of water ice (density estimated 2 g/cc) with escape velocity about 500 m/s, one is naturally interested :w

 

[Hercuflea]

Fabulous. Even though they could have done this in the 70s on nuclear thermal rockets...

I have more faith in private space companies.

 

[mheslep]

Fabulous. Even though they could have done this in the 70s on nuclear thermal rockets...
...

Do you have an example design in mind? Yes the nuclear power was available, the liftoff thrust was available, the specific impulse was an improvement over chemical rockets, but I don't know of anything in that era with the required specific impulse to go orbit hopping as has Dawn, i.e. an ion drive above 3000 seconds. Nuclear explosive propulsion (Orion) does not count.

 

[zoki85]

I think attempt to go to Mars in '70s had more chances to end in tragedy than not.

 

[HowardHughes]

So basically when NASA gets there, there will already be a fully established colony set up a decade before by SpaceX and co.

 

[marcus]

More about the conjecture that Mars might have a reservoir of subsurface ice in the "Northern lowlands":
http://science.nasa.gov/science-news/science-at-nasa/2014/19dec_marswater/

Dawn spacecraft distance from Ceres is now 787,000 km (i.e. 0.005261 AU)

As I recall it was 900,000 km from destination last Saturday, so in about 6 days it has closed in by more than 100,000 km. Seems to be on schedule to reach Ceres by 1 March. Will have to begin slowing down in order not to overshoot I suppose. Maybe gravity (orbital dynamics) will take care of that if it just turns off the solar-electric thrusters now and then.

 

[Kechel8]

Spectacular! Do we send matthew mcconaughey? ;)

 

[Firedog89]

Let's say we make to Mars, what will be the next step Europa? What about interstellar travel? Would that even be practical considering Einstein states that no man-made object can travel at the speed of light?

 

[Monsterboy]

http://www.universetoday.com/117384/nasas-curiosity-rover-detects-methane-organics-on-mars/

In how many ways can methane be produced on Mars non-biologically?

 

[progyan]

Setting foot on Mars would certainly be one of the greatest achievements of mankind since it would only be the second time since we ever set foot on any place besides our
planet.

 

[marcus]

http://www.universetoday.com/117384/nasas-curiosity-rover-detects-methane-organics-on-mars/

In how many ways can methane be produced on Mars non-biologically?

I'm not sure who here would be good to ask. Astronuc maybe? Almost certainly some of us have backgrounds in chem or chemical engineering. I don't know which would be the most likely pathways for producing CH₄ under Mars conditions. Nonbiological methane is common in outer solar system, e.g. moons of Saturn. Titan's atmosphere is largely methane, if I remember correctly. Hydrogen and Carbon are common elements and methane is a simple combination, likely to occur (in non-oxidizing conditions) and very stable (as long as there is not a lot of oxygen).

The catch is that oxygen, if present, will break down methane into carbon dioxide and water. If there free oxygen or oxygen molecules running around loose ready to react with stuff, it is called an "oxidizing environment". Methane tends not to form and does not readily accumulate under oxidizing conditions. But you can still have traces of it.
Mars is more oxidizing than not. So the question is: assuming no life, no biological action, what could have formed traces of methane in Mars atmosphere?

I'm no chemistry expert, but here's a unexpert suggestion to get the ball rolling. Mars has some water vapor in its atmosphere (it even has water ice at the poles) and
Mars has a lot of CO₂ in its atmosphere. Under the action of sunlight (especially UV) water vapor in atmosphere will slowly break down producing hydrogen and oxygen, and hydrogen will occasionally react with CO₂ to form methane, and water again.
As I recall, this reaction is even energetically favored, it would like to happen!
4H₂ + CO₂ --> CH₄ + 2H₂O

 

[marcus]

A Ceres Wonderland.
Due to mechanical wear, the Dawn craft lost "wheel control" after a number of years of voyaging---one or more of its gyroscopes (used for attitude control) wore out.
So when it needs to change orientation (to direct thusters, to keep solar panels in full sunlight etc. ) it has to use hydrazine. they mention that in the song.

Ceres is a huge H₂O resource with a surface escape velocity of only 500 m/s. From my perspective it has to be exciting that we are about to get a close look.
So ...

 

[Monsterboy]

Whether we find methane,chloro-benzene or any other organic compound ,only way to be certain about life on Mars is to directly FIND living organisms there ,or is it? Is there any organic compound that we are sure that it cannot exist without living organisms producing it? If there is any such thing ,we should start looking for that.

 

[phinds]

Whether we find methane,chloro-benzene or any other organic compound ,only way to be certain about life on Mars is to directly FIND living organisms there ,or is it? Is there any organic compound that we are sure that it cannot exist without living organisms producing it? If there is any such thing ,we should start looking for that.

It is my strong impression from what I have read that there are compounds that if seen in sufficient, sustained, quantities would indicate life forms as they would not as far as is known be producible/sustainable through geologic activity. I believe oxygen is one such but not the only one. No such concentrations of any have been seen on Mars. That absence does not guarantee that there are NOT life forms on Mars but it likely does mean that we're going to need direct observation to see if there is anything there.

 

[Monsterboy]

Lets have look at the hurdles for manned exploration of Mars.

http://www.space.com/25392-manned-mars-mission-astronaut-vision.html

Recently, scientists have begun realizing that spaceflight can cause serious and perhaps permanent vision problems in astronauts.

"Over the last 40 years there have been reports of visual acuity impairments associated with spaceflight through testing and anecdotal reports," a 2012 NASA report about spaceflight-related vision problems states. "Until recently, these changes were thought to be transient, but a comparison of pre- and postflight ocular measures have identified a potential risk of permanent visual changes as a result of microgravity exposure."

The problem is not confined to just a few isolated individuals, either. Postflight examinations performed on about 300 American astronauts since 1989 showed that 29 percent of space shuttle crewmembers (who flew two-week missions) and 60 percent of International Space Station astronauts (who typically spend five or six months in orbit) experienced a degradation of visual acuity, according to a report published this year by the U.S. National Academy of Sciences.

http://www.space.com/18980-radiation-manned-exploration-deep-space.html
http://news.discovery.com/space/history-of-space/mission-to-mars-health-risks-1107182.htm

Let us count the ways that the human body falls apart without gravity:

1) Bone loss of one percent per month.

2) Fainting spells (women more than men) after re-entering a gravitational field.

3) Cognitive problems including Alzheimer's-like symptoms.

4) Weakness and lack of cardiovascular fitness.

5) Muscle atrophy.

All of these medical conditions would make it tough for the crew to build a shelter when they land on the Red Planet, for example.

"What happens if they land on Mars and try to lift an object that's fairly or reasonably heavy, they could herniate their discs

Radiation:
The combined effects of background cosmic rays from extragalactic sources and extreme radiation events from the sun make space travel too hazardous for an estimated six months there and six months return.

Lead shields actually create secondary radiation when struck by cosmic rays, while water, perhaps the best form of protection, would have to be several meters thick to get enough protection. ("Houston calling Water Balloon 1, do you copy?")

Lead and water, in any case, are very heavy for the quantities that would be required, making them an expensive shielding to launch.

Pick astronauts that have never smoked, never been around smokers, and have a built-in genetic resistance to radiation damage. "We didn't know about this (ability) five or ten years ago, we should have an answer in another ten or 15 years,"

The crew needs either a small unit inside the ship or a vehicle design that rotates around a central pivot point (think 2001: A Space Odyssey). Hargens said a rotating arm of one-kilometer diameter will produce the equivalent of the gravity felt on the Earth at sea-level.
Smaller centrifuges have produced nausea among astronauts

Food:
However, studies show that radiation can damage the vitamins in food supplies, and the loss of even one vitamin in the food chain could cause serious health effects over a long trip. Little is known about the long-term effects of radiation on food supplies, since International Space Station (ISS) crews have been partially sheltered by Earth's magnetosphere.

Cabin Fever

Put six or seven people in a confined space for 18 months, send them to a place nobody's been before, with no way to escape, is likely to produce stress, tension and perhaps even severe psychiatric problems, according to NASA's 2009 Human Research Program report.

Based on studies in Antarctica and other isolated environments underwater, the report cited the risk of "increased human performance errors due to sleep loss, fatigue, work overload, and circadian desynchronization; and, increased errors due to poor team cohesion and performance, inadequate selection/team composition, inadequate training, and poor psychosocial adaptation."

Cosmonaut squabbles aboard the Russian Mir space station brought one mission home ahead of time, while NASA has also reported crew disputes among its astronauts

Some experts say the answer to all the medical, radiation, food and psychological issues is to get there faster.

Zubrin also went on the record to call VASIMR a "hoax."
"The insistence that we need a faster propulsion system just allows politicians to postpone a Mars mission,"

 

[mheslep]

Some experts say the answer to all the medical, radiation, food and psychological issues is to get there faster.

Zubrin also went on the record to call VASIMR a "hoax."
"The insistence that we need a faster propulsion system just allows politicians to postpone a Mars mission,"

I think Zubrin is a hoax

 

[Tsubaki]

I'm really pleased that they went to the Apollo-like design of the Orion Project. Upgradeable modules based on the greatest achievement in scientific history really can't fail us. It's an exciting time to be involved in science and engineering.

 

[Astronuc]

http://www.universetoday.com/117384/nasas-curiosity-rover-detects-methane-organics-on-mars/

In how many ways can methane be produced on Mars non-biologically?

The article mentions "an abiotic chemistry, such as a reaction between the mineral olivine (Mg,Fe silicate) and water, could be the generator." Olivine and certain minerals may support a type of Fischer-Tropsch synthesis, in which H2 and CO2 can form methane or simple alkanes. The following article indicates that "magnetite, chromite and other metal-rich minerals found on the olivine surface catalyze the formation of CH4, because of the low temperature of the system."
http://www.geochemicaltransactions.com/content/12/1/6
and http://www.lpi.usra.edu/meetings/abscicon2010/pdf/5427.pdf

As marcus mentioned, methane is ubiquitous in the outer regions of the solar system, and the methane could have originated from long ago from the same sources as those of Jupiter's and Saturn's moons.

 

[mheslep]

Large amounts of methane occur elsewhere, on Titan for instance, 1.4% of the atmosphere, which have https://solarsystem.nasa.gov/scitech/display.cfm?ST_ID=2298 So I'm curious as to why methane on Mars is of any special interest?

 

[Chronos]

That is irrelevant, as you should realize. Let's try to stick with science here.

 

[Monsterboy]

That is irrelevant, as you should realize. Let's try to stick with science here.

What's irrelevant?

 

[Monsterboy]

http://www.thespacereview.com/article/308/1

A magnetic field around the spacecraft might reduce the need for heavy shielding.

 

[OmCheeto]

http://www.thespacereview.com/article/308/1

A magnetic field around the spacecraft might reduce the need for heavy shielding.

We were just discussing that in another thread the other day.

 

[Monsterboy]

Large amounts of methane occur elsewhere, on Titan for instance, 1.4% of the atmosphere, which have https://solarsystem.nasa.gov/scitech/display.cfm?ST_ID=2298 So I'm curious as to why methane on Mars is of any special interest?

Yet all anybody seemed to be talking about when the US and Indian spacecraft s were approaching Mars was methane!. Media hype I guess.

 

[marcus]

Hi M_boy, I appreciated very much your post #68 where you reviewed the mental&physical health hazards of lengthy manned space missions and gave these links to sources

Lets have look at the hurdles for manned exploration of Mars.

http://www.space.com/25392-manned-mars-mission-astronaut-vision.html

http://www.space.com/18980-radiation-manned-exploration-deep-space.html
http://news.discovery.com/space/history-of-space/mission-to-mars-health-risks-1107182.htm

One thing about PF format is that when I click on "reply" it drops anything in your post that is formatted as a quote. So the above is all I get, as a quote in your post.
If you think the passages you quoted from those sources might be of subsequent value you can include them as quotations but not formatted as quote. For example by INDENTING. Or by doing what I do a lot which is to use this kind of quote/endquote break:
===quote [example] ===
whatever :)
==endquote==
Actually the hazards you reviewed in your post sobered me up a lot about humans ever getting to Ceres, and a subsurface ICE CAVERN habitat.
You'd almost have to do genetic modification on our species genome to get a version that could thrive in low gravity without such awful bone loss and kidney stones etc.
Maybe robots could build the habitat and then bring to life some frozen embryo humans that had been transported to Ceres in shielded containers. There must be ways around all the harm---and it could be a lot of fun living in 3% gravity subsurface Ceres.

 

[Astronuc]

Deep space is a rather inhospitable place!

For beings used to 1g, 0g or near-0g is problematic. If one was to evolve in zero-g, it would be challenging to live in something stronger. One would required some type of exoskeleton, but that wouldn't address circulatory issues.

Solar and cosmic radiation are problematic. In the absence of a magnetic field and atmosphere, a fair amount of shield is necessary, primarily hydrogenous to stop high energy protons and neutrons, then some high-Z material for gammas and X-rays. Spallation reactions and anti-particles are a factor in shielding design.

 

[marcus]

Astronuc thanks! Let's see how Monsterboy's post #68 quotes about medical hazards look in alternative formats. The INDENT button is at the top of the reply space, just to the left of the smiley symbol---you select the passage and click the button. The rest is a kind of haphazard quote of Mboy post #68, to sample format styles.

===quote Mboy==
...
...
http://www.space.com/25392-manned-mars-mission-astronaut-vision.html

"Over the last 40 years there have been reports of visual acuity impairments associated with spaceflight through testing and anecdotal reports," a 2012 NASA report about spaceflight-related vision problems states. "Until recently, these changes were thought to be transient, but a comparison of pre- and postflight ocular measures have identified a potential risk of permanent visual changes as a result of microgravity exposure."​

The problem is not confined to just a few isolated individuals, either. Postflight examinations performed on about 300 American astronauts since 1989 showed that 29 percent of space shuttle crewmembers (who flew two-week missions) and 60 percent of International Space Station astronauts (who typically spend five or six months in orbit) experienced a degradation of visual acuity, according to a report published this year by the U.S. National Academy of Sciences.
http://www.space.com/18980-radiation-manned-exploration-deep-space.html
http://news.discovery.com/space/history-of-space/mission-to-mars-health-risks-1107182.htm

Let us count the ways that the human body falls apart without gravity:

1) Bone loss of one percent per month.

2) Fainting spells (women more than men) after re-entering a gravitational field.

3) Cognitive problems including Alzheimer's-like symptoms.

4) Weakness and lack of cardiovascular fitness.

5) Muscle atrophy.

All of these medical conditions would make it tough for the crew to build a shelter when they land on the Red Planet, for example.

"What happens if they land on Mars and try to lift an object that's fairly or reasonably heavy, they could herniate their discs
Radiation:
The combined effects of background cosmic rays from extragalactic sources and extreme radiation events from the sun make space travel too hazardous for an estimated six months there and six months return.​

Lead shields actually create secondary radiation when struck by cosmic rays, while water, perhaps the best form of protection, would have to be several meters thick to get enough protection. ("Houston calling Water Balloon 1, do you copy?")

Lead and water, in any case, are very heavy for the quantities that would be required, making them an expensive shielding to launch.

Pick astronauts that have never smoked, never been around smokers, and have a built-in genetic resistance to radiation damage. "We didn't know about this (ability) five or ten years ago, we should have an answer in another ten or 15 years,"
The crew needs either a small unit inside the ship or a vehicle design that rotates around a central pivot point (think 2001: A Space Odyssey). Hargens said a rotating arm of one-kilometer diameter will produce the equivalent of the gravity felt on the Earth at sea-level.
Smaller centrifuges have produced nausea among astronauts

Food:
However, studies show that radiation can damage the vitamins in food supplies, and the loss of even one vitamin in the food chain could cause serious health effects over a long trip. Little is known about the long-term effects of radiation on food supplies, since International Space Station (ISS) crews have been partially sheltered by Earth's magnetosphere.

Cabin Fever:
Put six or seven people in a confined space for 18 months, send them to a place nobody's been before, with no way to escape, is likely to produce stress, tension and perhaps even severe psychiatric problems, according to NASA's 2009 Human Research Program report.

Based on studies in Antarctica and other isolated environments underwater, the report cited the risk of "increased human performance errors due to sleep loss, fatigue, work overload, and circadian desynchronization; and, increased errors due to poor team cohesion and performance, inadequate selection/team composition, inadequate training, and poor psychosocial adaptation."

Cosmonaut squabbles aboard the Russian Mir space station brought one mission home ahead of time, while NASA has also reported crew disputes among its astronauts​

==endquote==

 

[Astronuc]

The problem is not confined to just a few isolated individuals, either. Postflight examinations performed on about 300 American astronauts since 1989 showed that 29 percent of space shuttle crewmembers (who flew two-week missions) and 60 percent of International Space Station astronauts (who typically spend five or six months in orbit) experienced a degradation of visual acuity, according to a report published this year by the U.S. National Academy of Sciences.

That could be related to the ocular pressure. The body doesn't have a gravity field to pull the blood down from the head.

There is also a radiation effect. One should look at the eye problems of airline crews, especially those with long-term international service. It's worse in space.During grad school, I was part of student team that looked at propulsion systems for missions to Mars. Basically, it came down to how to get to Mars, ASAP! That meant as high a specific power as feasible, and minimize the mass of the spacecraft . We also proposed putting a space station in orbit, which would be ready to receive astronauts when they arrived. Basically, there is a lot of infrastructure that needs to be put in place for missions to Mars. This includes placing habitat modules (including power systems) on the surface.

 

[marcus]

All really interesting. I also was intrigued by the quotes that Mboy gathered in post #68. The passage you quoted just now was one that I took from him.
I'm beginning to get very interested in the genetic adaptation of humans to low gravity. How much is reasonably possible? (and it would mean the GMO humans would not be able to visit Earth!, or could do so only with special precautions for limited periods of time)

 

[OmCheeto]

...(and it would mean the GMO humans would not be able to visit Earth!, or could do so only with special precautions for limited periods of time)

Like fish and humans! We can both visit each other's environment, for a bit. :)

hmmm...

Perhaps our descendants will have developed the following technology by then:

 

[Elite Jacob]

I think we need to stop exploring and start building. There are experiments that need to be done off world for a better understanding of the physics of our universe. All of the science behind building life some where other than Earth is hypothetical until we actually start trying. We will most likely have to build a rail system in orbit to transport materials. Would using the area of the atmosphere around the poles where the ozone layer is thinnest make reaching escape velocity require less energy/effort? Less atmosphere less friction. Even a launch from a mountain may make reaching orbit cost less. I've said enough, considering my pay grade. ;)

 

[256bits]

Thinner ozone layer does not mean thinner atmosphere., although it does raise a point on how the density of the atmosphere varies in altitude at the poles vs at the equator due to the Earth's rotation. Launches are done closest to the equator as possible in order to take advantage of the greater tangential velicity of the surface of the earth. Launching higher up, such as on top of a mountain does not make all that much of a difference since most of the fuel is used to increase the velocity ( for a satellite ) to obtain orbit, rather than overcoming the gravity of the earth.

 

[Monsterboy]

I'm beginning to get very interested in the genetic adaptation of humans to low gravity. How much is reasonably possible? (and it would mean the GMO humans would not be able to visit Earth!, or could do so only with special precautions for limited periods of time)

Maybe if genetic modification be done so that GM humans can retain their bone and muscle strength in low gravity, they won't need any special precautions to take while in a place where gravity is stronger. They might also need a secondary blood pumping system to pump blood down so that the heart can pump it up ,this might solve the problem mentioned by Astronuc.

The body doesn't have a gravity field to pull the blood down from the head.

The crew needs either a small unit inside the ship or a vehicle design that rotates around a central pivot point (think 2001: A Space Odyssey). Hargens said a rotating arm of one-kilometer diameter will produce the equivalent of the gravity felt on the Earth at sea-level.
Smaller centrifuges have produced nausea among astronauts

A centrifuge with 1km diameter might be too much ,there are other proposed solutions to create artificial gravity ,like this one http://arxiv.org/ftp/gr-qc/papers/0607/0607086.pdf

We will show that superconductors indeed could be used to
produce non-classical gravitational fields, based on the established disagreement between theoretical prediction and
measured Cooper-pair mass in Niobium. Tate et al failed to measure the Cooper-pair mass in Niobium as predicted by
quantum theory.

most of this paper went over my head because i know next to nothing about quantum field theory and stuff ,i would appreciate if anyone can validate the paper and explain it in layman terms.

 

[mfb]

I think we need to stop exploring and start building. There are experiments that need to be done off world for a better understanding of the physics of our universe. All of the science behind building life some where other than Earth is hypothetical until we actually start trying.

It is often easier to reproduce the conditions of space on Earth compared to shooting an experiment into space. Even if you need micro-gravity, for short time-scales there are towers (~3-4s) or airplanes (~20s) and those are much cheaper.

Launching higher up, such as on top of a mountain does not make all that much of a difference since most of the fuel is used to increase the velocity ( for a satellite ) to obtain orbit, rather than overcoming the gravity of the earth.

Well, you still have the atmosphere. Starting on a mountain means less drag. The other downsides (worse infrastructure, in particular no direct access via ships, and no suitable places close to a coast to prevent accidents) are more important, however - nearly all launch sites are close to sea level.

 

[Elite Jacob]

Excellent points. What about the feasibility of a magnetic rail system for achieving escape velocity? Also I wasn't aware we had the technology to simulate the conditions of different celestial bodies. I can't help but think saying the data collected from a experiment on our planet would always be an acceptable substitution and be completely accurate for one done in space or on an alternate celestial body. An example would be, what happens to water if released from the ISS? Could the same conditions be duplicated on the planets surface?

 

[LachyP]

This will be an amazing day for mankind.. And I am just admiring the fact that I get to witness such an enormous step in space exploration :)

 

[mfb]

Excellent points. What about the feasibility of a magnetic rail system for achieving escape velocity?

Then height is absolutely critical.
Rocket sled launch
StarTram

Also I wasn't aware we had the technology to simulate the conditions of different celestial bodies. I can't help but think saying the data collected from a experiment on our planet would always be an acceptable substitution and be completely accurate for one done in space or on an alternate celestial body.

Well, it depends on the type of experiment. We do not have realistic martian soil here, for example, so doing experiments with it is problematic, and to explore its composition we have to send probes to Mars.

An example would be, what happens to water if released from the ISS? Could the same conditions be duplicated on the planets surface?

Most of it evaporates, some parts form many small ice crystals. You get the same result if you release water into a vacuum on earth. The ice crystals will fall down on Earth while the astronauts can see them longer in an orbit, but that happens "long" (seconds) after the release process.

 

[marcus]

Maybe if genetic modification be done so that GM humans can retain their bone and muscle strength in low gravity, they won't need any special precautions to take while in a place where gravity is stronger. They might also need a secondary blood pumping system to pump blood down so that the heart can pump it up ,this might solve the problem mentioned by Astronuc...

Thanks for the comment. I found your summary of the health hazards associated with low gravity very helpful. Ceres 3% gravity is certainly a serious problem.

But as far as is known Ceres is second only to Earth in having the most water of anybody in the inner solar system. From its known density, the outer icy mantle is thought to be around 100 km thick. With only a thin crust of rock and dust covering it. As a major water resource orbiting at 2.8 AU from sun, with escape velocity some 500 m/s (making it comparatively easy to land and take off) it's likely, I think, to play a significant role in human history.

I checked http://neo.jpl.nasa.gov/orbits/fulltraj.jpg (google "where is dawn now?" ) and the remaining distance is about 500 thousand km, or about 3.39 thousandths of an AU.
If all goes well it will be in orbit sometime in early March.

I googled "dawn journal" and saw that the mission director and chief engineer Marc Rayman has posted a December 29 entry which gives a lot of background on the dwarf planet.
http://dawnblog.jpl.nasa.gov/2014/12/29/dawn-journal-december-29/
http://dawnblog.jpl.nasa.gov

 

[Astronuc]

Mars mission: Could US girl, 13, be first on red planet?
http://www.bbc.com/news/magazine-29516432

Alyssa is studying science and several languages and became the first person to attend all three of Nasa's world space camps. Her call sign at the US space agency is "Blueberry".
The teenager from Baton Rouge, Louisiana, says failure is not an option. And her father says he has the next 20 years of work planned out.

The needs to be a lot of infrastructure in place for a trip to Mars. It doesn't need to be one way.

The propulsion systems need to be developed. An on orbit station should be put in place in advance of a crew arriving.

One concept that was kicked around about 30 years ago was a large magnetic launch system from LEO, or GEO. Basically there would be a substantial thrust system to hold the launcher in place, and a long enough launcher to get a craft up to a reasonable velocity, at a tolerable acceleration. The system is more or less a large recoilless rifle, based on a nuclear thermal rocket (NTR) system.

The problem however is cost. It costs a lot to put a kg in LEO, and more in GEO.

 

[Loren]

They always say that.

Then the political wind changes...

 

[mfb]

And her father says he has the next 20 years of work planned out.

I hope he has good alternative plans as well.

An on orbit station should be put in place in advance of a crew arriving.

Do we really need an orbiting station (=life-support and so on)? The astronauts have to arrive with(in) a fully functional station that can support them for a long time, and it is reasonable to use the same station to go back (and if astronauts stay in orbit they can use it the whole time). They will need some sort of station on the surface and supplies in orbit for the way back. Both can (but do not have to) be sent there in advance.

 

[Loren]

I hope he has good alternative plans as well.

Do we really need an orbiting station (=life-support and so on)? The astronauts have to arrive with(in) a fully functional station that can support them for a long time, and it is reasonable to use the same station to go back (and if astronauts stay in orbit they can use it the whole time). They will need some sort of station on the surface and supplies in orbit for the way back. Both can (but do not have to) be sent there in advance.

For one thing, I am thinking that the astronauts will not be spening a lot of time on the surface due to all the perchlorate in the soil. That stuff is a nasty, dusty, toxin that will be hard to keep out of the crew quarters. At least it is going to be challenging dealing with that stuff and that may limit the number of times they perform EVAs.

Having a service module that is already awaiting in advance of the crew could increase mission flexibility, supplies, and return fuel. A lot of resources will be required just getting down to the surface and back into Martian orbit.

 

[mfb]

For one thing, I am thinking that the astronauts will not be spening a lot of time on the surface due to all the perchlorate in the soil. That stuff is a nasty, dusty, toxin that will be hard to keep out of the crew quarters. At least it is going to be challenging dealing with that stuff and that may limit the number of times they perform EVAs.

Having some gravity is good for the health and the astronauts might be able to use some ressources from Mars there. Also, controlling robots is easier if you are close to them - in an orbit, you frequently lose connection if you don't have multiple relay satellites.

Having a service module that is already awaiting in advance of the crew could increase mission flexibility, supplies, and return fuel.

How? Where is the advantage of having that orbiting there in advance, compared to attaching it to the station where it (a) can be monitored or even repaired if necessary (b) can be used as emergency backup if something goes wrong on the way to Mars (c) can be part of a shielding concept (d) provides more space for the crew?

A lot of resources will be required just getting down to the surface and back into Martian orbit.

Sure.

 

[Loren]

Having some gravity is good for the health and the astronauts might be able to use some ressources from Mars there. Also, controlling robots is easier if you are close to them - in an orbit, you frequently lose connection if you don't have multiple relay satellites.
How? Where is the advantage of having that orbiting there in advance, compared to attaching it to the station where it (a) can be monitored or even repaired if necessary (b) can be used as emergency backup if something goes wrong on the way to Mars (c) can be part of a shielding concept (d) provides more space for the crew?
Sure.

One simple scenario is that two ships do not need to carry identical cargo. While one ship may carry crew another can carry provisions. One ship is configured with a lander. The second is configured to carry additional life support materials and/or instruments. Remember, only the crew capsule must return to Earth, so a unmanned supply ship does not need fuel and provisions for a return trip. Again, this means more provisions can be taken on the first ship than can be stored on the crew module's ship.

Secondly, while the crew capsule transit time needs to be as quick as possible, there are no such constraints on an advanced unmanned ship. The unmanned ship can be launched at one launch window and the crewed capsule could follow on the next available window, which is probably 1 to 2 years later.

This means that you have some flexibility in the mechanism the first ship uses to reach Martian orbit, such as taking a lower energy transit, saving fuel which can be traded for provisions.

I am sure there would be other advantages. The real question is whether the additional costs and risks of a second ship is outweighed by those advantages. I can't say, but a two ship approach does expand the opportunities and options for a manned mission versus a larger single ship - if not at least something for our minds to ponder.

Unfortunately, I feel somewhat pessimistic about the whole space program.

I remember the last launch of the Space Shuttle. We were out walking our dogs when it launched and I looked North to see the vapor trail as it ascended (we live about 25 miles south of the launch pad).

The vapor trail was highly scattered, shifting left and right due to different wind directions at different altitudes, but the end result was this trail that violently twisted one direction, then the next multiple times as it rose into the sky. I remarked to my girlfriend that I wish I had brought my camera as this parodied the direction of NASA - being politically pulled one direction then to the next...

 

[mfb]

One simple scenario is that two ships do not need to carry identical cargo.

No one said that.

Remember, only the crew capsule must return to Earth, so a unmanned supply ship does not need fuel and provisions for a return trip.

Yes this is obvious. We are talking about the way to Mars.

While one ship may carry crew another can carry provisions. One ship is configured with a lander. The second is configured to carry additional life support materials and/or instruments.

You can stick them together, with the advantages listed above.
You can save delta_v if you give the spacecraft many years for the trip, right - then you have to deviate significantly from a Hohmann orbit. That is an advantage, yes.

I can't say, but a two ship approach does expand the opportunities and options for a manned mission versus a larger single ship - if not at least something for our minds to ponder.

It is certainly an option, I just do not see why this "should be" (Astronuc).

 

[Loren]

...I just do not see why this "should be" (Astronuc).

Okay. I just don't see why is "shouldn't be" either.

 

[Jupiter5]

This is a one way trip,they will not be able to return to Earth ever.