NASA NASA: We're sending humans to Mars

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NASA has officially announced plans to send humans to Mars using the Orion space capsule, with a target launch timeframe in the 2030s. There is skepticism about the feasibility of this timeline, given NASA's budget constraints and the technical challenges involved. Some participants in the discussion express doubts about the scientific value of a manned Mars mission, suggesting that establishing a moon base first would be more practical. Others speculate that the mission announcement may be a strategic move to garner public interest and funding for NASA. Overall, while excitement exists about the prospect of humans on Mars, many believe significant hurdles remain before this can become a reality.
  • #61
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?
 
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  • #63
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.
 
  • #64
Monsterboy said:
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
 
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  • #65

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 ...
 
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  • #66
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.
 
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  • #67
Monsterboy said:
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.
 
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  • #68
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,"
 
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  • #69
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
 
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  • #70
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.
 
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  • #71
Monsterboy said:
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.
 
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  • #72
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?
 
  • #73
That is irrelevant, as you should realize. Let's try to stick with science here.
 
  • #74
Chronos said:
That is irrelevant, as you should realize. Let's try to stick with science here.
What's irrelevant?
 
  • #77
mheslep said:
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.
 
  • #78
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
Monsterboy said:
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.
 
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  • #79
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.
 
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  • #80
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==
 
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  • #81
marcus said:
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.
 
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  • #82
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)
 
  • #83
marcus said:
...(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:

 
  • #84
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. ;)
 
  • #85
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.
 
  • #86
marcus said:
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.
Astronuc said:
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.
 
  • #87
Elite Jacob said:
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.
256bits said:
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.
 
  • #88
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?
 
  • #89
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 :)
 
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  • #90
Elite Jacob said:
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.
 

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