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#676 Re: Terraformation » How far? » 2005-11-04 13:51:54
Just to cut to the chase, how far would you want terraforming to go for you to be satisfied?
As for myself, I would be happy if I could take a stroll on the Martian surface with an oxygen mask, a pea coat, and maybe some goggles to keep out the sand. If terraforming went that far, even not in my lifetime, I would be happy.
Which reminds me of some Martian art by I forget who. I'll try and find it...Until the red planet is covered in a sea of sugar cane to power the methanol power stations. There is no point in wasting time when only earth like conditions will cut the amount of money that must be spent on sustaining the colony.
Actually, just having enough surface pressure to be able to dispense with pressure suits will make life on Mars much more comfortable.
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#677 Re: Not So Free Chat » Should we be con-artists? » 2005-11-04 13:34:46
And I say that those of us who want to go to Mars need to be a little more like that elderly lady who went to the Bank of Canada.
What? Grab the bankers by the short and curlies?
No, play 'em. Like in "The Sting"
Do you really want to be perceived as a con-artist?
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#678 Re: Human missions » One man one way suicide mission... » 2005-11-04 02:14:47
Energia with EUS can throw 35,680kg to C3=0, 31,091kg to C3=10, or 17,446kg to C3=50. A manned mission to Mars will use C=15 so interpolating I get 24,207.5kg to TMI.
Most Mars Direct derivatives seem to call for minimum energy for the cargo missions (as low as C3=8 in a good year) and C3=25 for the manned mission.
Here are the C3 departure contours for 2007 - just in case 
#679 Re: Interplanetary transportation » Falcon 1 & Falcon 9 » 2005-11-03 19:10:55
SpaceX sets date
SpaceX has scheduled its first launch of the Falcon I low-cost booster for 31 October from Kwajalein Atoll in the Pacific, carrying the US Air Force Academy’s FalconSat-2 space plasma research satellite into low Earth orbit.
October 25, 2005: The target launch date for the Falcon I maiden flight is now late November to early December from our island launch complex in the Kwajalein Atoll. All systems will be ready for flight by the end of this week with the exception of Merlin qualification, which we are extending by four weeks for added surety.
#680 Re: Human missions » NASA 2006 Budget » 2005-11-02 23:47:48
I really think spending is out of control in the united states.
I think a lot of people agree with you ...
Mission unthinkable: Disbanding NASA
http://www.newscientist.com/channel/opi … 5.900.html
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#681 Re: Human missions » NASA 2006 Budget » 2005-11-02 22:55:13
Here is the breakout for FY2005 ...
#682 Re: Water on Mars » Looking for information on how to test for water » 2005-11-02 22:06:02
In Gusev Crater, mini-TES will look for minerals like carbonates and sulfates that form only in the presence of water. Finding them will provide strong evidence that Gusev was once a lake.
I don't know much about the lunar and Martian geology. Are these carbonates and sulfates also on the moon?
It is very unlikely. On Mars the current theory is that there were lakes and oceans at one time giving time for such minerals to form. Any water on the Moon is thought to have come from asteroid and comet impacts. And, as Dook said, will probably be in the form of relatively pure ice.
You may wish to learn more about infrared spectroscopy ...
http://en.wikipedia.org/wiki/Infrared_spectroscopy
H2O will have a particular spectral fingerprint.
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#683 Re: Water on Mars » Looking for information on how to test for water » 2005-11-02 18:24:31
I think you want a near-infrared spectrometer.
Here is a site about the one carried by the Mars rover ...
Particularly ...
http://minites.asu.edu/Mini-TES_Overview.pdf
Good luck with your project. Let us know what you go with.
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#684 Re: Science, Technology, and Astronomy » Space Ring to Stop Global Warming? » 2005-11-02 18:06:38
Question is what caused the temperature rise, and the CO2 increase ?
A 1991 Science article titled "solar activity closely associated with climate" showed that, unsurprisingly, solar activity is well correlated with global average temperature ...
http://www.tmgnow.com/repository/solar/lassen1.html
The big effect of the increased solar activity is in changing cloud cover. This is important because water vapor is 10000 times more effective as a greenhouse gas than CO2. Note that clouds are left out of most climate models because they are "too difficult."
http://www-ssc.igpp.ucla.edu/IASTP/43/
An increase of just 0.2% in the solar output could have the same affect as doubling the carbon dioxide in the Earth's atmosphere.
http://solar-center.stanford.edu/sun-on … -warm.html
Hmmm, when was the last time you read that in a newspaper?
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#685 Re: Terraformation » Arguments for terraforming Mars » 2005-11-02 16:05:14
Is this your web site David?
http://projectmarsltd.org/home.html
That's a great graphic on the home page 8)
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#686 Re: Meta New Mars » Your Opinion On New Mars » 2005-11-02 15:23:43
Myself I have been looking forward to the release of this movie :
http://www.themarsunderground.com/
Any news on that ?
The distributor
http://www.ocule.com/market.cfm?market_id=2
says they'll be screening it Friday (Nov 4) at AFM in Santa Monica. Good luck Mars Underground movie 8)
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#687 Re: Science, Technology, and Astronomy » Laser beamed power question » 2005-11-02 14:08:41
From
http://powerweb.grc.nasa.gov/pvsee/publ … _3213.html
r_spot = 0.61 * d * λ / r_lens
So r_spot, the beam radius at the receiver (containing 84% of the initial beam power), is proportional to the distance from the sender to the receiver, multiplied by the wavelength of the light, and divided by the radius of the sender (r_lens). So we need to decrease the wavelength (UV, x-rays, etc) or use very large senders - the same huge scopes that the astronomers use, but in reverse.
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#688 Re: Science, Technology, and Astronomy » Space Ring to Stop Global Warming? » 2005-11-02 13:00:25
It should be noted that this "study" assumes the burning of all possible fossil fuels, is replete with the phrase "but we didn't take into account" and uses words like "holistic."
Their projected vegetation map for high CO2 is interesting - most of the northern hemisphere becomes temperate forest and most of the southern hemisphere becomes tropical forest.
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#689 Re: Science, Technology, and Astronomy » Laser beamed power question » 2005-11-02 03:19:16
I understand how an atmosphere causes laser beam dispersal (widening of an initially narrow beam), but what causes beam dispersal in a vacuum? Is it possible to prevent with clever optics?
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#690 Re: Life support systems » Sterling engine+solar= neat powersource - EETimes article » 2005-11-02 01:49:08
Here are some papers (brochures, really) describing some light-weight concentrators.
Ultra-light stretched Fresnel lens solar concentrator for space power applications (2003)
http://www.entechsolar.com/SpacePaper5.pdf
^ Made of 140 micron thick silcon rubber, stows flat, has pictures of it unfolding, adds 11% efficiency to give 27% efficiency overall, promises 0.5 kW/kg within 10 years.
Stretched-Lens Photovoltaic Concentrator Arrays for NASA's Moon/Mars Exploration Missions (2004)
http://www.entechsolar.com/IECEC04.pdf
^ Predicts 1.0 kW/kg by 2025
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#691 Re: Interplanetary transportation » Solar Sails » 2005-11-02 00:36:18
Interesting paper on solar sails by Zubrin ...
http://www.pioneerastro.com/Projects/USSIT/ussit.html
From the summary ...
Solar sails have long been theorized as capable of sailing interplanetary and interstellar space. Conventional solar sail designs use aluminized plastic support membranes to form the sail, which limit their characteristic accelerations to ~0.001 m/s2, because the plastic dominates sail mass. Such a sail is limited to travel within our solar system for missions lasting less than 10 years. By eliminating the plastic substrate after sail deployment, it is possible to increase the sail acceleration three-hundred fold. This sail can venture anywhere in our solar system within a year. Introducing perforations in the sail, similar to an antenna mesh but at a very small nano-scale, can reduce sail mass such that accelerations of 0.5 to 5 m/s2 are feasible. At these accelerations, a spaceship could visit the Oort cloud beyond our planetary system (~10,000 AU) within several decades. If these perforations were eventually made of carbon nano-structures rather than out of a nano-grid of aluminum, accelerations of 10 to 100 m/s2 may be possible, enabling interstellar travel to Centauri in less than a century. In its nearest-term and most conservative form, the utltra-thin solar sail will revolutionize outer solar system exploration. In its ultimate form, it will give humanity the stars. We therefore conclude that the development of ultra-thin solar sail technology must be aggressively pursued.
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#692 Re: Interplanetary transportation » Launch dates for low energy transfers » 2005-11-01 18:42:41
There is a low energy [Earth-Mars] transfer launching in 2031, from the data I have got it looks like it is in the first quarter of 2031.
Can anyone tell me the exact date of this launch window? The module is to be sent with the least possible energy.
http://www.jaqar.com/swingby.html says ...
dep. 2/18/2031 arr. 1/1/2032 has delta-v = 5.4 km/sec to high Mars orbit.
Launch window for approx. 5.4 km/sec delta-v runs from 2/13 through 2/22.
Launch window for approx. 5.5 km/sec delta-v runs from 2/10 through 2/25.
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#693 Re: Not So Free Chat » 2004 MN4 » 2005-11-01 04:08:17
Looking at the image of the orbit of this NEO, it would appear that venus has a very good chance of being struck as well. I kind of also wonder if a close pass to venus could as well alter its orbit?
Nasa has a nice java applet where you can see the relative positions of the objects in their orbits ...
http://neo.jpl.nasa.gov/cgi-bin/db?name=99942
Apophis does get close to Venus in April 2016 - around 0.080 AU, which is about 30 times the distance from the Earth to the Moon (30 luna distances). Otherwise it is at least twice that, and usually much more.
However, after Apophis encounters Earth in April 2029 (at under a tenth of a luna distance), it is very likely that its orbit will change so that it doesn't approach Venus closely again. The Nasa applet doesn't show the change - probably because, depending on how the encounter goes, a range of new orbits is possible.
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#694 Re: Science, Technology, and Astronomy » Space Ring to Stop Global Warming? » 2005-11-01 01:15:40
With all the evidence of change, especially in the arctic, it's crazy that we still have people denying global warming.
I think an average global temperature rise has been well established. I believe the dispute is over what is causing it and if/how much it will continue to rise in the future.
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#695 Re: Meta New Mars » WIKI: We now have a useable wiki... » 2005-11-01 00:42:34
MySQL returned error "1016: Can't open file: 'searchindex.MYI' (errno: 145) (db66a.pair.com)".
Error Code 145 (Table has been marked as crashed and should be repaired):
The table has crashed, this can be sorted in various ways. Chose the method which suits you below:
1. using the folowing query
REPAIR TABLE tablename;
2. or using mysqlcheck repair for 3.23.38 and above, i.e., in shell/telnet/ssh type while mysql is running:
mysqlcheck -r -u mysqlusername -p databasename
3. via myisamchk repair functions while mysql is shutdown/stopped in shell/telnet/ssh type :
myisamchk -r -u root -p databasename
option #3 most likely requires server and mysql root access to first stop mysql and then run myisamchk repair options.
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#696 Re: Terraformation » Thoughts on producing an atmosphere on the Moon » 2005-10-31 03:53:56
Do we want a process where leakage of an Amino acid atmosphere scatters the building blocks for life across the open wastes of space?
Well now, if you don't want your leaking gases to just spiral into the Sun, then you'll need to accelerate them to 50 km/sec. Room temperature (300 K) gases only average 0.5 km/sec, so I don't think you're going to get that by accident. You'd need some sort of accelerator. Also remember that the Moon isn't going to create any atoms for you. You're going to have to replace whatever you lose.
Frankly they might as well build the entire colony underground noosfractal, use the surface as the roof. No need to build when already have one in place.
I suppose as long as the underground dome was large enough to have weather - say 1 km radius - and sufficient quantities of natural light could be funneled down to it, then it wouldn't be a bad life. Now we just need a way to excavate a couple of cubic kilometers of luna rock.
The point of an aminoacid atmosphere is that it is sufficiently heavy to stay wrapped around the Moon as opposed to a NO2 or CO2 atmosphere which would not be sufficient.
Even providing a bar of atmospheric pressure would make life significantly easier, even if you couldn't breath it. It'd be best if you see through it though. Are there molecules that heavy that are transparent to visible frequencies?
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#697 Re: Life support systems » Sterling engine+solar= neat powersource - EETimes article » 2005-10-31 03:05:23
Ease of manufacture encourages solar panels on Mars.
I think that's how it might work out, although solar panel manufacture on Mars isn't as easy as it is on the Moon - no free vacuum - in fact lots of dust to dim and scratch 
Still, the Sterling engines are complex in comparison. Here is a report on the solar dishes that Sterling Energy is using (they were developed by Sandia) ...
http://www.energylan.sandia.gov/sunlab/ … r_dish.pdf
A 25 kW dish is 40 ft tall and weighs 7 tons (0.003 kW/kg - don't think we're going to be shipping those to Mars). Apparently they cost $150,000 each right now, but Sterling Energy is hoping to get that down to $50,000 a piece fairly quickly.
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#698 Re: Human missions » Lunar Carbon? » 2005-10-30 21:57:53
high efficiency CIGS solar cells deposited on thin titanium foil.
Thanks SpaceNut, these CIGS solar cells are interesting. CIGS = copper-indium-gallium-diselenide. You don't need a titanium substrate - it looks like any standard substrate will do. These guys claim 16.6% efficiency with an active film thickness of 3 microns. That's 1.5 kW/kg with a foil substrate. If we make our own substrate by melting luna regolith as discussed above that's 10 kW/kg ! That's 100 times better than what the ISS uses today. Deposition temperature is around 800 K. Apparently they are resistant to hard radiation.
Sweet.
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#699 Re: Meta New Mars » Viewing Mars Tonight » 2005-10-30 04:14:47
Interstatials on the karmic manifold.
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#700 Re: Life support systems » Sterling engine+solar= neat powersource - EETimes article » 2005-10-30 04:09:00
More economical on Earth, but not Mars ?
I think in theory, still more economical on Mars, but in practice? In theory, the efficiency of Sterling/solar is 40% vs. 10-30% for solar cells. I saw one claim for 38% with solar cells if you used a concentrator - a lens-like dome over the solar cell.
But, if you bring the Sterling/solar from Earth, it is likely to be heavier than thin film solar. If it is more than twice as heavy, then you have a lower kW/kg
If you make it on Mars, it is likely to be way more complex than thin film solar to manufacture - you have to make a Sterling engine as well as the parabolic mirrors. So higher risk and maybe the additional manufacturing equipment (literally) outweighs the efficiency benefit. But maybe you'd only need to bring hyper-efficient Sterling engines from Earth and you could make the parabolic mirrors in-situ for a higher kW/kg. Worth considering.
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