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STEPHEN HAWKING: WE HAVE 100 YEARS TO LEAVE EARTH

 
 
farmerman
 
  1  
Reply Wed 14 Jun, 2017 07:07 pm
@edgarblythe,
perfect examples of genetic drift
0 Replies
 
oralloy
 
  1  
Reply Wed 14 Jun, 2017 08:51 pm
@farmerman,
farmerman wrote:
a long duration burt (1000 years or more).

Are you sure you understand that correctly? I thought the longest-duration gamma ray bursts were several hours long.
farmerman
 
  1  
Reply Thu 15 Jun, 2017 05:10 am
@oralloy,
not according to some calcs tht look at distributive means of kinetic energy in a variably sized GRB' and the times involved to attain all that "E". Id read in SCience a discussion about how many GRB's (especially in those at binary stars and more), take place as pulses of energy that can take a millenium or more to fully disgorge.


In any case WR 104 is either gonna be GRB or not,(theres no real consensus bsed upon spectroscopic analyses on metallicity of these stars-They are in Sagittarius )but now we have a target time period to work around as we begin to establish "species wide goals".
0 Replies
 
edgarblythe
 
  1  
Reply Thu 15 Jun, 2017 05:14 am
I support making plans before it becomes an emergency. Not by my interpretation, but by what scientists can come up with.
farmerman
 
  1  
Reply Thu 15 Jun, 2017 05:32 am
@edgarblythe,
yeh, I imagine itll be at least 1000 years before they can agree that theres a catastrophe looming.
0 Replies
 
edgarblythe
 
  1  
Reply Sat 17 Jun, 2017 01:58 pm
https://scontent.fhou1-1.fna.fbcdn.net/v/t1.0-9/19260635_598445113659195_4273056059937955797_n.jpg?oh=694e69cebb702c2d9f2fb76325ba0670&oe=599FB566
0 Replies
 
edgarblythe
 
  1  
Reply Sun 18 Jun, 2017 03:09 pm
https://scontent.fhou1-1.fna.fbcdn.net/v/t1.0-9/19114015_10155171032684845_6042271032992525870_n.png?oh=1c41c05efb0b6b62093d5b817a0b32b1&oe=59CE47C4
0 Replies
 
edgarblythe
 
  1  
Reply Tue 20 Jun, 2017 02:11 pm
A new study suggests that the cancer risk on a Mars mission due to galactic cosmic-ray radiation could be double what existing models predict. Image Credit: NASA

According to a publicity campaign launched on behalf of a paper authored by UNLV (University of Nevada, Las Vegas) Professor Frank Cucinotta, the new findings show “collateral damage from cosmic rays increases cancer risks for Mars astronauts“.

However, an examination of the paper itself shows no analysis of experimental methods or results, because no experiments were done and no data was taken. Rather, the much-ballyhooed paper is a discussion of a computer model that Prof. Cucinotta has created which claims to have the power to predict radiation-induced cancer occurrences. In short, there’s no real news.

Furthermore, to the extent that the model in question has any empirical foundation, it is based on irrelevant prior experiments done in which researchers subjected mice to radiation dose rates millions of times greater than astronauts would receive on their way to Mars.

One such example is the illustrative piece of nonsense entitled “What happens to your brain on the way to Mars“, published on May 2, 2015, in the open-access journal Science Advances. In the paper, a group of radiation researchers claimed that their recent experiment causing memory loss to mice by administering very large doses of galactic cosmic ray (GCR)-like high energy radiation has serious implications for human Mars exploration. According to the authors, similar effects might severely impact astronauts going to Mars, thereby placing the feasibility of such enterprises in serious question.

However, in this typical mouse trial, the victims were given a dose of 30 rads (0.3 Gray) at a rate of 100 rads per minute. On a Mars mission, astronauts would receive a dose of 1 rad per month during the 6-month outbound and return transfers as well as about 0.5 rad per month during 18 months on Mars, for a total of 21 Rads. (1 Gray = 100 rads = 100 cGray. For GCR 1 Gray = 6 Sieverts = 600 rem.) Space dose rates can be found in The Cosmic Ray Radiation Dose in Interplanetary Space – Present Day and Worst-Case Evaluations by R.A. Mewaldt, et al., 2005.

The 4-million fold difference in dose rate between such lab studies and spaceflight is of critical importance. It is a well-known finding of both chemical and radiation toxicology that the effects of large doses of toxins delivered suddenly are entirely different from the effect of the same amount of toxin delivered in very small amounts over a long time span. The difference is that the body’s self-repair systems cannot deal with a sudden dose that they can easily manage if received over an extended period.

For example, if an individual were to drink one shot of vodka per second for 100 seconds, he would die; however, if the same person drank one shot of vodka a month for 100 months, he would experience no ill effects at all. This is about the same ratio of dose rates as that which separates the invalid work reported in the What happens to your brain on the way to Mars paper (1.6 rad per second) from that which would be experienced by astronauts in space (1 rad per month.)

It should also be added that mouse studies are not an accurate predictor of cancer occurrence in humans; e.g., it is possible to induce tumors in mice by rubbing their stomachs. Such treatment is not known to be a hazard to people.

It is true that small amounts of toxins received over a long period can statistically increase a person’s risk of ill effects – at least according to the hyper-conservative Linear-No-Threshold (LNT) model of toxicology. However, we already have data that shows that the accumulation of slow rates of cosmic-ray radiation received during long-duration spaceflight is not a show stopper for human Mars exploration. GCR dose rates in low-Earth orbit are about half those in interplanetary space.

Therefore, there are a dozen cosmonauts and astronauts – Padalka, Malenchenko, Avdeyev, Polyakov, Solovyov, Krikalyov, Titov, Manarov, Foale, Fincke, Pettit, Walz, Kelly, Whitson – who have already received Mars mission equivalent GCR doses during extended space missions without any radiological casualties.

Furthermore, since the International Space Station (ISS) is continually manned, whereas Mars missions are only in space for about 40 percent of their mission time, the total GCR dose (measured in person-rems) that the ISS program crews will receive over the next ten years of planned operations is about the same as would be received by a series of five teams of five people each if they were launched to Mars every other year over the same period. Thus, in fact, the ISS program has already accepted the same level of GCR risk for its crews as would be faced by an ongoing human Mars exploration program.

Galactic cosmic radiation is not a show stopper for human Mars exploration and should not be used as an excuse for delay. The space program costs many billions of dollars, which is spent at a real cost to meeting human needs elsewhere. That fact imposes a moral obligation on the program to move forward as quickly and efficiently as possible. It is understandable that radiation researchers should want to justify their funding. However, they should not spread misinformation to promote themselves at such extraordinary expense to the public.

###

The views expressed in this Op-Ed are solely those of the author and do not, necessarily, reflect those of SpaceFlight Insider.




Read more at http://www.spaceflightinsider.com/editorial/opinion-radiation-hucksters-strike-again/#tShr9IsuzVLh0YPO.99
edgarblythe
 
  1  
Reply Wed 21 Jun, 2017 05:56 pm
The above article makes radiation hazard seem less.
0 Replies
 
Krumple
 
  1  
Reply Wed 21 Jun, 2017 11:34 pm
@edgarblythe,
I'm going to go a slightly different route with this topic, so if anyone cares read on.

I think it goes without needing in depth explanation to say a hundred years is far too soon for us to establish any off Earth colony. But why? Economics. Yes money. Human well being takes a back seat to economic importance. We don't lead by saving ourselves we lead by what can make a good business model.

The government lied (Nixon) to cram sugar into everything to make money at the expense of health then paid people to toss salt under the bus. It's all a lie. Sugar is the real cause of heart disease and high blood pressure not salt.

With that all said I love the idea and morn my age because I'm jealous of the people whom get to be the first off world human colonists. In fact I love this idea so much I wrote a few songs about it.

On song is a dual point of mocking abducties and exploring the idea of being kidnapped by aliens and put in their zoo back on their home planet. The idea would be worth being a prisoner at the knowledge you were on another world.

The other is about just that, being the first to live on another ball of rock and losing your Earthling title.

We have barely visited other astral bodies the thought we can make it happen in the next hundred years seem impossible even if we were putting upmost focus on it, which we are not.

I doubt the one way ticket to Mars will even happen like they say, within the next hundred years. Due to money. There is no money in it. It won't happen.
0 Replies
 
Setanta
 
  2  
Reply Thu 22 Jun, 2017 12:53 am
@edgarblythe,
edgarblythe's source wrote:
The 4-million fold difference in dose rate between such lab studies and spaceflight is of critical importance. It is a well-known finding of both chemical and radiation toxicology that the effects of large doses of toxins delivered suddenly are entirely different from the effect of the same amount of toxin delivered in very small amounts over a long time span. The difference is that the body’s self-repair systems cannot deal with a sudden dose that they can easily manage if received over an extended period.


This is something which I have mentioned before in these fora, in another thread. On an extended flight, well outside the bounds of the Earth's magnetosphere, serious radiation protection will be needed. Although the methodology of the report mentioned in EB's post is absurd, the risk to crew in a flight to Mars is very real. If a solar flare goes off while the crew is in flight, they would need very effective shielding--either an artificially generated magnetic field (requiring a significant energy expenditure) or heavy-metal and water shielding in the hull of their vessel. The radiation from a solar flare could reach 120 to 150 REMs (roentgen equivalent man, a now-outdated term for radiation exposure--the inhabitants of Terra receive about one third REMs every year in background radiation). The thing is, the radiation exposure would reach at least 100 REMS in a matter of minutes, and could persist at that level or higher for from ten to twenty minutes. How great the dose would be, and how long one would be exposed would determine if one died of radiation toxicity within a few months, a few weeks, a few days or a few minutes. This issue is one which, in what I have read over the last few years, NASA seems to take far too casually. As I and others have mentioned, the problem with going to Mars is expense. We sure as hell don't want to send people out there without serious radiation shielding for the crew, and for their potable water and food. That means either a very energy-expensive artificial magnetic field, or very, very heavy shielding provided by heavy metals and a huge quantity of water.

People get all starry-eyed and goofy (pun intended) over things like going to Mars, and give little or no thought to the practical considerations. I am alarmed tho think that "people" in this context seems to include a lot of those jokers at NASA.

ADDENDUM: The comment in that opinion piece about the ISS being continually manned is either made disingenuously, or from sheer ignorance. The ISS is well within Terra's magnetosphere.
Leadfoot
 
  1  
Reply Tue 27 Jun, 2017 03:12 pm
@Setanta,
I wouldn't write off shielding with a magnetic field so quickly. A superconducting magnet consumes virtually no energy other than that needed to keep it at operating temp. That might be easy to do in the vacuum of space.

There are plenty of other reasons 100 years is a bad timeline though.
0 Replies
 
Setanta
 
  1  
Reply Tue 27 Jun, 2017 05:26 pm
To send even just a dozen crew to Mars would require a vessel the size of a smallish asteroid. You'll need a ****-load of SCMs, and those will not be cheap, nor would the maintenance on them while in use. Typical superconducting wire is made from Niobium and Titanium, neither of which litters the landscape here on Terra. Believe it when I tell you that you have no real notion of the scale required for this. A moderate solar flare would leave a radiation residue, which by itself would be immediately toxic and ultimately fatal. That means you don't just have a pod for the crew--you have to shield their quarters, you have to shield their stores, you have to shield their equipment, both on-board, and that intended for use on Mars. All of which is to say, you can only do it practically by shielding the entire vehicle. For all the efficiency of having conductors with virtually no resistance, you still have to generate the power that is being conducted. That means boosting all of the necessary equipment up out of the mother well, as well as the necessary fuel for generating the current. At no time have I said that it cannot be done--the question is the expense, which will be the limiting factor for any such mission.

Go babble to some of your Jesus-freak buddies, will ya? I doubt that you have given this the thought that I have for the last 25 years, and I don't believe you are very well informed on this subject. You're out of your league, even given the incredibly inflated ego you always displayed.
0 Replies
 
Leadfoot
 
  1  
Reply Wed 28 Jun, 2017 06:50 am
Set just hates it when I agree with him. And I was thinking about this before he was born.
edgarblythe
 
  1  
Reply Sat 1 Jul, 2017 05:48 pm
As NASA makes plans to one day send humans to Mars, one of the key technical gaps the agency is working to fill is how to provide enough power on the Red Planet’s surface for fuel production, habitats and other equipment. One option: small nuclear fission reactors, which work by splitting uranium atoms to generate heat, which is then converted into electric power.

NASA’s technology development branch has been funding a project called Kilopower for three years, with the aim of demonstrating the system at the Nevada National Security Site near Las Vegas. Testing is due to start in September and end in January 2018.

The last time NASA tested a fission reactor was during the 1960s' Systems for Nuclear Auxiliary Power, or SNAP, program, which developed two types of nuclear power systems. The first system — radioisotope thermoelectric generators, or RTGs — taps heat released from the natural decay of a radioactive element, such as plutonium. RTGs have powered dozens of space probes over the years, including the Curiosity rover currently exploring Mars.

The second technology developed under SNAP was an atom-splitting fission reactor. SNAP-10A was the first — and so far, only — U.S. nuclear power plant to operate in space. Launched on April 3, 1965, SNAP-10A operated for 43 days, producing 500 watts of electrical power, before an unrelated equipment failure ended the demonstration. The spacecraft remains in Earth orbit.

Russia has been far more active developing and flying spacecraft powered by small fission reactors, including 30 Radar Ocean Reconnaissance Satellites, or RORSAT, which flew between 1967 and 1988, and higher-powered TOPAZ systems. TOPAZ is an acronym for Thermionic Experiment with Conversion in Active Zone.

A photograph of the SNAP-8 generator from the Lewis Research Center, part of NASA's Systems for Nuclear Auxiliary Power (SNAP) program. Here, engineers exposed the system to shocks and vibrations expected to occur during a launch into space and subsequent maneuvering.
A photograph of the SNAP-8 generator from the Lewis Research Center, part of NASA's Systems for Nuclear Auxiliary Power (SNAP) program. Here, engineers exposed the system to shocks and vibrations expected to occur during a launch into space and subsequent maneuvering.

NASA has funded several nuclear power technology efforts in the 50 years since SNAP, but financial, political and technical issues stymied development. Three years ago, the agency’s Game Changing Development program backed Kilopower, with the goal of building and testing a small fission reactor by Sept. 30, 2017, the end of the current fiscal year. The project is costing about $15 million.

"It'll be the first time that we operate a fission reactor that could be used in space since [the] 1960s SNAP program," said Lee Mason, who oversees power and energy storage technology development at NASA’s Glenn Research Center in Cleveland.

The tests in September are designed to validate Kilopower’s design and performance. After that, NASA would be ready to proceed with developing a higher-fidelity system for testing on Mars or elsewhere, Mason said.

The test reactor, which is about 6.5 feet tall (1.9 meters), is designed to produce up to 1 kilowatt of electric power, but to keep costs down, the test unit does not include a full array of Stirling engines to convert energy generated by the fission process into heat. Thermal simulators will be used for the balance of the engines to verify the reactor’s power output, Mason said in an interview with Space.com.

NASA’s interest in fission resurfaced after a 2010 study that looked at options for RTG systems.

"At that point, we were trying to find a small fission reactor that could provide similar power output as the radioisotope power systems," Mason said.

NASA engineers figure human expeditions to Mars will require a system capable of generating about 40 kilowatts of power, which is about what is needed for "about eight houses on Earth," according to the agency. Curiosity’s RTG was designed to supply about 125 watts — less energy than what is needed to power a microwave oven — though power levels fall as the radioactive plutonium decays. [How Will a Human Mars Base Work? NASA's Vision in Images]

Solar power is another option, but that would restrict power generation to regions that are exposed to enough sunlight to charge batteries. Inside the moon’s Shackleton Crater, for example — a prime candidate for lunar sorties due to its water resources — it is completely dark. The sunniest spots on Mars receive only about one-third the amount of sunlight as Earth does.

"If you want to land anywhere, surface fission power is a key strategy for that," Michelle Rucker, an engineer at NASA’s Johnson Space Center in Houston, said during a presentation in December to NASA’s Future In-Space Operations working group.

Fission reactors also can continue working in adverse weather conditions, such as Mars’ ubiquitous dust storms.

"We’ve landed some really cool things on Mars and they’ve had some pretty remarkable power systems … but they’re not going to cut it for human missions," Mason said during last month’s Humans to Mars Summit in Washington, D.C.

The biggest power requirement for future human expeditions is running the equipment to produce fuel, air and water, plus running the habitat and recharging batteries for rovers and science equipment. NASA envisions sending four or five small fission reactors, each capable of generating about 10 kilowatts of power, to Mars, Mason said at the Humans to Mars Summit.

The units would be launched cold and activated once they reach their destinations.

"They’re not operating at launch, whereas once you fuel an RTG, it’s operating, and you have to process the thermal output," Mason said. "The reactors also have a very low radiological inventory at launch — less than 5 curies — so it’s benign … There are no fission products until the reactor is turned on, and that’s when there will be some radiation."

Partners in the Kilopower project include NASA’s Glenn Research Center, the Department of Energy, Los Alamos National Lab and the Y12 National Security Complex, which supplies the reactor’s uranium.

Irene Klotz can be reached on Twitter at @free_space. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.
0 Replies
 
Setanta
 
  1  
Reply Sat 1 Jul, 2017 08:34 pm
@Leadfoot,
You'll go to Hell for lyin', too.
Leadfoot
 
  2  
Reply Sun 2 Jul, 2017 06:22 am
@Setanta,
Wasn't intentional if I did. Were you hatched, not born?
edgarblythe
 
  1  
Reply Tue 4 Jul, 2017 07:18 pm
NASA’s rover has photographed a strange formation of rocks that some UFO hunters claim are really fossilized “alien bones” proving there’s life on Mars.

The one-ton Curiosity rover, which has been scouring the surface of the planet since August 2012, sent back a pair of images that resemble thigh bones and a hip bone protruding from the planet’s surface.

The alien-hunter group Martian Archaeology presented the images in a video claiming the photos are evidence of “signs of life”:


Read more at http://www.wnd.com/2017/07/nasa-rover-spots-alien-thigh-bone-on-mars/#LmKsYz6lDbUe3fRu.99
http://www.wnd.com/files/2017/07/alien-bone-3-NASA.jpg
However, NASA has said the following 2014 photo – which some have claimed could be an “alien thigh bone – is just another weathered Martian rock.
Read more at http://www.wnd.com/2017/07/nasa-rover-spots-alien-thigh-bone-on-mars/#LmKsYz6lDbUe3fRu.99
0 Replies
 
farmerman
 
  1  
Reply Tue 4 Jul, 2017 07:21 pm
@edgarblythe,
One can clearly see that the thigh bone's connected to the foot bone.
0 Replies
 
Setanta
 
  0  
Reply Tue 4 Jul, 2017 09:02 pm
@Leadfoot,
Snide bastard, go gabble with your Jesus freak friends--they'll probably appreciate the elementary school humor.
0 Replies
 
 

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