Domain: spaceref.ca
Stories and comments across the archive that link to spaceref.ca.
Comments · 9
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Re:Water on mars for self-sustaining city
According to this reflectors are not sufficient to stop the harmful radiation.
This might lead to he building of growth chambers under a radiation shield comprised of regolith with light provided from collectors located on the surface. NASA-sponsored research has shown that low power LEDs (light emitting diodes) could find applicability as a low power option for illuminating Martian crops.
A little research into your theories before posting might be in order.
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Gogo Canada!
Also on the PSLV-C20 launch are the Canadian military satellite SAPPHIRE, and the twin spacecraft BRITE-Austria and UniBRITE, developed in Canada for TU Graz and University of Vienna respectively. ISRO put out a pretty good brochure describing the launch.
You can find some good photos of the stacking and launch vehicle integration here, here, and here. You can watch the launch live on Monday morning here.
Needless to say, we're all pretty stoked around here ^__^
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Re:Where do the hydrocarbons come from?
The methane is believed to come from geological processes and not from life.
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Re:By now?"Let's assume a mass of 0.25 solar masses."
Proxima Centauri, a red dwarf, is 0.12 solar masses, about 270,000 AU away, and was discovered in 1915.
It seems brown dwarfs cap at around 90 jovian masses (0.08 solar masses).
"The Nemesis theory says that it exists about 50,000-100,000 AU away, has an orbital period of 26 million years, and is a brown dwarf."
ballpark absolute magnitude of a brown dwarf: 17
absolute magnitude of the sun: 4.8
difference: 12.2
Apparent magnitude of the sun at 1 AU: -26.73
apparent magnitude of sample dwarf at 1 AU: -26.73 + 12.2= -14.53
Add 5 apparent magnitude for multiple of ten of distance
100,000 AU = 10^5 AU, 5 * 5 = 25, 25 + (-14.53) = 10.47
Apparent magnitude of sample dwarf at 100,000 AU = 10.47 (round to 11)
Coincidentally, the apparent magnitude of Proxima Centauri is also 11
Apparent magnitude of Neptune, discovered 1846 = 8 (about 16 times brighter)
Apparent magnitude of Pluto, photographed 1915 = 14 (about 16 times dimmer)
Apparent magnitude visible by ground-based telescopes = 27 (2.5E6 times dimmer)
Apparent magnitude visible by Hubble = 30 (4.0E7 times dimmer)
From the looks of things, Nemesis would have been showing up in astronomical photographs starting from the last decade or so of the Nineteenth Century. Curiously, the first confirmed sighting of a brown dwarf was in 1995 (first theorized in the 1960s). Now, unless the spectral pattern put out by this brown dwarf Nemesis somehow looks like much larger, hotter and brighter stars, it would have been Big News in Astronomy that such an odd star exists, regardless of its distance from us.
"It's like putting a telescope in your car while driving down the road and expecting to be able to find a parallax between observations"
Time between the two photographs over which the motion of Pluto first became apparent: 6 days
Orbital period of Pluto: 90,600 days
Sweep of arc made by Pluto for its discovery ~ 1 minute, 16 seconds of arc
Time between the two photographs over which the motion of Quaoar first became apparent: 180 minutes
Orbital period of Quaoar: 105,000 days
Sweep of arc made by Quaoar for its discovery ~ 1.5 seconds of arc
You say Nemesis may have an orbital period of 26 million years. Kepler says an object 100,000 AU away should have an orbital period of about 32 million years. We'll take the slower number:
Sweep of arc made by Nemesis in the past 50 years ~ 2 seconds of arc
And an interesting quote about the discovery of real nearby brown dwarfs in Epsilon Indi, 12 light-years away (source):"Because this system is so close to us, it appears to move quite rapidly in the sky," says Dr. Volk. "We were able to confirm our detection--and rule out a more distant background object--within a few weeks since we could detect the motion of the system relative to the background stars relatively quickly."
If 12 light-years "appears to move quite rapidly in the sky," why not 1.2 light-years? -
More coverageHere's a little more information about TEKh-42 (the technical name). Quote:
[Purpose of Nanosputnik is to support development of satellite control techniques, monitoring of satellite operations, and research on new attitude system sensors and other components.]
Also, space.com has an article mentioning it.
I'm surprised there isn't more coverage. It is a little reminiscent of the latter days of the Apollo program when there was little/no coverage on the press, or to a greater extent the latter days of SpaceLab.
-F
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Re:He doesn't need to succeed.
But private enterprise won't even bother if there's not a bottom line.
I'm not sure I'm completely agree. The way I see it, there's going to be three different types of space endeavours in the future:
* Government-run: Pretty much mostly what we have now. Governments sending things up for science, prestige, and military purposes.
* Private for-profit (commercial): Right now this is mostly satellites, but should expand to things like space tourism, mining, orbital power satellites, shipment, manufacturing, space porn, etc.
* Private non-profit (altruism): This is the one which everyone seems to overlook, mostly because it really hasn't been done so far. These are done for prestige, to attract more donations, to assure a place in history, to advance mankind, to pad one's ego, etc.
This last one I think has a lot of potential. The best near-term examples is the Planetary Society's Cosmos I, which will launch the first solar sail spacecraft lin April of this year. It'll also be the first-ever space mission by a non-profit group (I think).
Another example I often cite is Elon Musk, who had a "Mars Oasis" project for launching an experimental greenhouse on the surface of Mars. There wouldn't be any direct payback from this -- just an entry in the history books and the knowledge that he'd advanced mankind. However he put this on hold when he did a thorough analysis and found that launch costs would be the dominant part of the price tag. Instead, he's invested his efforts in SpaceX; hopefully once he gets launch costs down he'll return to the Mars Oasis project. -
Re:The ISS's lifeboat
Well, Nasa has stopped their ISS crew rescue vehicle program last year for cost reasons. See here
.Thanks for the info. I found some additional information . There was some talk of using this gold-plated mini-shuttle as the rescue vehicle. Then this design was being worked on. Even though its budget was, as Lars pointed out, cut for 2002, they still test launched it as recently as December 2001. This link has some info on the use of the Soyuz as the rescue vehicle.
I hadn't realized that US budget decisions had cut the ISS back to a skeleton crew. Here is a press release from a US Senator commenting on a recently released independent review of the Space Station's Science programs.
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Re:Canada's Mars Mission
It was heard about here in a conference announcement from Marc Garneau and discussed on Slashdot.
And recently, it was pointed out that Canada does have critical exploration technology for drilling for samples. -
Re:More taxpayers cash flushed down the lavatory
Actually the entire NASA Budget for the last two years has been just under $15B with a full $15B budgeted for FY2003.
If you we take the US Census Bureau as an authority then the current US Population is about 286.5 Million.
$15,000,000,000 / 286,500,000 = $52.36, or almost exactly $1/week per American.
Plus, I find these statistics of cost per American pretty irrelevant, since the poorest 20% of Americans don't pay income tax and therefore are contributing nothing to run NASA. On the other hand, the Bush tax cuts passed last year by repealing the inheritance tax gave Bill Gates a $30B tax cut, enough to pay NASA's whole budget for two straight years!