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Comment Re:Martian soil is like toxic.... (Score 4, Informative) 134

Perchlorates may lead to health problems but likely not deadly. According to some groups, perchlorate affects only the thyroid gland. Because it is neither stored nor metabolized, any effects of perchlorate on the thyroid gland are fully reversible. Some other studies suggest that perchlorate may have pulmonary toxic effects as well. In this article it is mentioned that exposure could be managed. As for using the soil for agriculture, there are several technologies can remove perchlorate, via treatments ex situ and in situ. Ex situ treatments include ion exchange using perchlorate-selective or nitrite-specific resins, bioremediation using packed-bed or fluidized-bed bioreactors, and membrane technologies via electrodialysis and reverse osmosis. In ex situ treatment via ion exchange, contaminants are attracted and adhere to the ion exchange resin because such resins and ions of contaminants have opposite charge. It may be beneficial to process it. Researchers have proposed a biochemical approach for the removal of perchlorate from Martian soil that would not only be energetically cheap and environmentally friendly, but could also be used to obtain oxygen both for human consumption and to fuel surface operations. In any event, precautions will have to be taken but the presence of perchlorates in the soil does not appear to be 'show stopper' at this point.

Comment Should start with going to Phobos (Score 1) 684

Phobos has been proposed as an early target for a manned mission to Mars. The tele-operation of robotic scouts on Mars by humans on Phobos could be conducted without significant time delay, and planetary protection concerns in early Mars exploration might be addressed by such an approach.

Phobos has also been proposed as an early target for a manned mission to Mars because a landing on Phobos would be considerably less difficult and expensive than a landing on the surface of Mars itself. A lander bound for Mars would need to be capable of atmospheric entry and subsequent return to orbit, without any support facilities (a capacity that has never been attempted in a manned spacecraft), or would require the creation of support facilities in-situ (a "colony or bust" mission); a lander intended for Phobos could be based on equipment designed for lunar and asteroid landings. Additionally, the delta-v to land on Phobos and return is only 80% of that for a trip to and from the surface of the Moon, partly due to Phobos's very weak gravity.

The human exploration of Phobos could serve as a catalyst for the human exploration of Mars and be exciting and scientifically valuable in its own right.

Comment Re:Lower Gravity on Mars is a problem (Score 1) 261

Elon Musk recently posted on Twitter that is was not advocating setting off nukes on Mars but merely presenting it as one of the options available to quickly generating an atmosphere. Setting aside the problems of radiation and the mechanics of getting thousands of bombs to Mars, what would be the effect of nuking the poles?

The polar caps at both poles consist primarily (70%) of water ice. The northern polar cap has a diameter of about 1,000 km during the northern Mars summer, and contains about 1.6 million cubic kilometres of ice, which, if spread evenly on the cap, would be 2 km thick. (This compares to a volume of 2.85 million cubic kilometres for the Greenland ice sheet.) The southern polar cap has a diameter of 350 km and a thickness of 3 km. The total volume of ice in the south polar cap plus the adjacent layered deposits has also been estimated at 1.6 million cubic km.

So there are a few problems with this. First the northern pole region has a surface area of 3,141,590 sq km and the southern a further 384850 sq kms.. Even the mort powerful nukes only cover a few sq kms with the direct fireball. And even if they can vaporize the ice, it would condense and freeze in a short period of time due to the cold tempuratures. The Martian surface temperatures vary from lows of about 143 C (225 F) at the winter polar caps to highs of up to 35 C (95 F) in equatorial summer. The wide range in temperatures is due to the thin atmosphere which cannot store much solar heat, the low atmospheric pressure, and the low thermal inertia of Martian soil. The planet is also 1.52 times as far from the Sun as Earth, resulting in just 43% of the amount of sunlight.

In the long run, it might be easier to cool Venus with space shades than try to warm Mars.

Comment Lower Gravity on Mars is a problem (Score 5, Informative) 261

The surface gravity on Mars is 38% of that on Earth. It is not known if this is enough to hold a breathable atmosphere. Additionally, the lower gravity of Mars would require 2.6 times Earth’s column air mass to obtain 100 kPa pressure at the surface. Earth's atmosphere has a mass of about 5.15×1018 kg three quarters of which is within about 11 km of the surface. The atmosphere becomes thinner and thinner with increasing altitude, with no definite boundary between the atmosphere and outer space. The Kármán line, at 100 km, is often used as the border between the atmosphere and outer space. So the atmosphere on Mars would have to extend to 260kms to have the same surface air pressure as Earth.

Comment Sensory Deprivation and REST (Score 1) 155

Many associate Sensory deprivation with torture but short-term sessions have been described as relaxing and conducive to meditation. Sessions of up to 24 hrs for therapeutic purposes are referred to as Restricted Environmental Stimulation Therapy (REST) There is a substantial amount of research in treating addictive behaviors with REST is reviewed with smoking, overeating, alcohol consumption, and drug misuse. There are two types: Flotation REST and Chamber RESTIn chamber REST, subjects lie on a bed in a completely dark and sound reducing (on average, 80 dB) room for up to 24 hours. Their movement is restricted by the experimental instructions, but not by any mechanical restraints. Food, drink and toilet facilities are provided in the room and are at the discretion of the tester. Subjects are allowed to leave the room before the 24 hours are complete; however, fewer than 10% actually do. With regard to the article, I would be concerned as some studies have had participant experience hallucination after 48 hrs.

Comment Re:Similar Technique used by James Cameron in 1989 (Score 1) 234

"How many Olympic-sized swimming pools(OSSPs) does that make?
Based on a nominal depth of 2 m, this is 2,500,000 L (550,000 imp gal; 660,000 US gal) or, in terms of cubic volume, 2,500 m3 (88,000 cu ft), as is commonly quoted. So Cameron's big tank was the equivalent 11.36 OSSPs and the smaller one held 3.79 OSSPs.

Comment Similar Technique used by James Cameron in 1989 (Score 4, Interesting) 234

For the 1989 Movie The Abyss James Cameron shot the underwater sequences for the film were shot at an unfinished Cherokee Nuclear Power Plant, situated outside Gaffney, South Carolina, which had been abandoned by Duke Power. Two specially constructed tanks were used. The first one held 7.5 million US gallons (28,000 m3) of water, was 55 feet (18 m) deep and 209 feet (70 m) across. At the time, it was the largest fresh-water filtered tank in the world. Additional scenes were shot in the second tank, which held 2.5 million US gallons (9,500 m3) of water. The filmmakers had to figure out how to keep the water clear enough to shoot and dark enough to look realistic at 2,000 feet (700 m), which was achieved by floating a thick layer of plastic beads in the water and covering the top of the tank with an enormous tarpaulin.

Comment Wired into Home Theatre (Score 1) 158

I tried Chromecast but hated it. Eventually I realized the best solution was connecting my laptop to my home theatre via HDMI. When I need it I just select the video setting and when finished selected back to TV. No need for special apps or even an internet connection. Even when my TV is off I can play music from my laptop through the home Theatre speakers. With Blackberry Blend I can see my incoming email/BBMs when I am watching movies. Video chats on my big screen TV are amazing and remind me of the view screens in Star Trek. We are living in the future.

Comment What about the Toxic Soil on Mars? (Score 1) 48

Several Mars missions have reported a significant amount of Perchlorates in the Martian soil which is a problem as it is toxic to humans. This will prevent the use of the soil for agriculture and will be hard to avoid as colonists will track the dust into habitats. How do plans to colonize Mars deal with the presence of Perchlorates in the soil?.

Comment Major Problem (Score 1) 256

Yes a Colony on Venus would have water and sunlight but they would still be at the bottom of a gravity well(same for Mars). It would make more sense to establish a colony in space where you could find water and minerals in asteroids. Supply ships would not need to overcome gravity and return flights could take back precious minerals that would help fund the expense.

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