APOD: Dry Ice Pits on Mars (2011 Sep 26)

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Expand view Topic review: APOD: Dry Ice Pits on Mars (2011 Sep 26)

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by rstevenson » Mon Oct 03, 2011 8:17 pm

GaryR wrote:What I don't understand about the spent fuel rods is why they are stored at all instead of being used to generate more power if the rods are still "hot".
Basically, they're not hot enough. Which is why they're called "spent".

But they'll become valuable fuel again, as soon as we get the next generation of reactors going.

Rob

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by GaryR » Mon Oct 03, 2011 3:45 am

BMAONE23 wrote:I have to agree with you about the Nuclear Power and clean energy. The only real problem with Nuclear power is how the spent fuel rods are stored and cooled. Currently they are placed in spent fuel ponds that are kept cool by continually pumping water through them that is pumped by power produced on site. As long as the power plant continues to operate, the rod cooling system has power to function. If something happens to the plant and power stops, the fuel rods will heat up like what happened in Japan.
Nuclear power is very cost effective though with an average of 11.4 cents/KWH ($114/MWH) and a maximum cost of $121/MWH with a capacity factor of 90%
Geothermal is also very cost effective with an average of 10.17 cents/KWH ($101.7/MWH) and a maximum cost of $115.7/MWH and a capacity factor of 92%
Wind power is also fairly cost effective with an average of 9.7 cents/KWH ($97/mwh) and a maximum cost of $115/MWH but has a capacity factor of 34%
Solar Photovoltaic has an average cost of 21 cents/KWH ($210.7/MWH) and a maximum cost of $323.9/MWH but has a capacity factor of 25%
Solar Thermal has an average cost of 31 cents/KWH ($311.8/MWH) and a maximum cost of $641.6/MWH but has a capacity factor of 18%
The least expensive is Natural Gas with Advanced Combined Cycle with an average cost of 6.3 cents/KWH and a capacity factor of 87%

The "Clean Technologies" of Solar and Wind are too costly without Subsidies and not available on cloudy/stormy days or nights

What I don't understand about the spent fuel rods is why they are stored at all instead of being used to generate more power if the rods are still "hot".

Gary

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by NoelC » Sun Oct 02, 2011 3:02 pm

The "Clean Technologies" of Solar and Wind are too costly without Subsidies and not available on cloudy/stormy days or nights
Gee, it's too bad there haven't been any breakthroughs in battery technology over the past few decades. Oh, wait...

-Noel

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by BMAONE23 » Sun Oct 02, 2011 7:57 am

I have to agree with you about the Nuclear Power and clean energy. The only real problem with Nuclear power is how the spent fuel rods are stored and cooled. Currently they are placed in spent fuel ponds that are kept cool by continually pumping water through them that is pumped by power produced on site. As long as the power plant continues to operate, the rod cooling system has power to function. If something happens to the plant and power stops, the fuel rods will heat up like what happened in Japan.
Nuclear power is very cost effective though with an average of 11.4 cents/KWH ($114/MWH) and a maximum cost of $121/MWH with a capacity factor of 90%
Geothermal is also very cost effective with an average of 10.17 cents/KWH ($101.7/MWH) and a maximum cost of $115.7/MWH and a capacity factor of 92%
Wind power is also fairly cost effective with an average of 9.7 cents/KWH ($97/mwh) and a maximum cost of $115/MWH but has a capacity factor of 34%
Solar Photovoltaic has an average cost of 21 cents/KWH ($210.7/MWH) and a maximum cost of $323.9/MWH but has a capacity factor of 25%
Solar Thermal has an average cost of 31 cents/KWH ($311.8/MWH) and a maximum cost of $641.6/MWH but has a capacity factor of 18%
The least expensive is Natural Gas with Advanced Combined Cycle with an average cost of 6.3 cents/KWH and a capacity factor of 87%

The "Clean Technologies" of Solar and Wind are too costly without Subsidies and not available on cloudy/stormy days or nights

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by bystander » Sun Oct 02, 2011 2:10 am

Stick your head in the sand and pretend everything is ok and there is nothing you need to do.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by neufer » Sun Oct 02, 2011 1:58 am

BMAONE23 wrote:
Neufer,
I have to ask, What would you suggest we do as a society to eliminate our Evil Carbon Producing Energy Sources that wouldn't either
1) Bankrupt our governments
2) To avoid 1 above Overburden the populace via heavily increased Taxation
3) Eliminate 80% of the population
4) Convert the world to communism to eliminate the monitary system

Another option???
Take global warming seriously and try all options including nuclear.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by NoelC » Sat Oct 01, 2011 11:22 pm

How about a massive public works effort to manufacture and install 15 kW or so of solar panels on the roof of virtually every home in the country? With enough quantity / demand there would certainly be breakthroughs in pricing. This wouldn't bankrupt anyone any more than bailing out investment banks does.

-Noel

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by BMAONE23 » Sat Oct 01, 2011 8:49 pm

neufer wrote:(snip)
Of the 19 recognized polar bear subpopulations:
  • 1) eight are declining,
    2) three are stable,
    3) one is increasing, and
    4) seven have insufficient data>>
[/quote]

Neufer,
I have to ask, What would you suggest we do as a society to eliminate our Evil Carbon Producing Energy Sources that wouldn't either
1) Bankrupt our governments
2) To avoid 1 above Overburden the populace via heavily increased Taxation
3) Eliminate 80% of the population
4) Convert the world to communism to eliminate the monitary system

Another option???

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by NoelC » Fri Sep 30, 2011 7:29 pm

Jasev wrote:Any amature astronomer can clearly see this photo shows sun from the lower left
It's a really, REALLY good optical illusion. I started out thinking as you do, but read my posts above, and if you've got the bandwidth download the big "strip" image. It becomes pretty obvious which direction the light is coming from when you view the non-frost-covered parts, and it magically seems to "flip around" when you get to the pits.

Thank you, APOD folks, for making me distrust my eyes. :)

-Noel

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by neufer » Thu Sep 29, 2011 2:59 pm

BMAONE23 wrote:
neufer wrote:
mikef wrote:
So, here is my message to politically conservative people who doubt that humans are responsible for climate change.
The politically conservative people who really need convincing:
  • 1) don't believe in science & don't trust scientists and
    2) don't care if polar bears starve or if folks in Bangladesh drown.
As to #2 polar bears are thriving and have grown to a population estimated to be 25,000
as of the last survey from an estimated population of 20,000 at the prior survey.
The politically conservative people who really need convincing:
  • 3) put much greater weight on anecdotal evidence than on actual scientific studies.
http://en.wikipedia.org/wiki/Polar_bears#Population_and_distribution wrote:
<< It is difficult to estimate a global population of polar bears as much of the range has been poorly studied, however biologists use a working estimate of about 20,000–25,000 polar bears worldwide.

There are 19 generally recognized discrete subpopulations. The subpopulations display seasonal fidelity to particular areas, but DNA studies show that they are not reproductively isolated. The thirteen North American subpopulations range from the Beaufort Sea south to Hudson Bay and east to Baffin Bay in western Greenland and account for about 70% of the global population. The Eurasian population is broken up into the eastern Greenland, Barents Sea, Kara Sea, Laptev Sea, and Chukchi Sea subpopulations, though there is considerable uncertainty about the structure of these populations due to limited mark and recapture data.

Modern methods of tracking polar bear populations have been implemented only since the mid-1980s, and are expensive to perform consistently over a large area. The most accurate counts require flying a helicopter in the Arctic climate to find polar bears, shooting a tranquilizer dart at the bear to sedate it, and then tagging the bear. In Nunavut, some Inuit have reported increases in bear sightings around human settlements in recent years, leading to a belief that populations are increasing. Scientists have responded by noting that hungry bears may be congregating around human settlements, leading to the illusion that populations are higher than they actually are. The Polar Bear Specialist Group of the IUCN takes the position that "estimates of subpopulation size or sustainable harvest levels should not be made solely on the basis of traditional ecological knowledge without supporting scientific studies."

Of the 19 recognized polar bear subpopulations:
  • 1) eight are declining,
    2) three are stable,
    3) one is increasing, and
    4) seven have insufficient data>>

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by Chris Peterson » Thu Sep 29, 2011 2:13 pm

BMAONE23 wrote:If there were more openness then the debate might truly be settled but the techniques employed by Climate Scientists to avoid sharing data goes against the very methods they are supposed to stand for as scientists
Please understand that there is absolutely no debate inside the scientific community. The "debate" as it stands is a social/political fabrication, like those found around evolution or the age of the Earth.

Most raw climate data is publicly available. All of the conclusions that have been reached are based on science and models that are published and can be examined by anybody. Some raw data is either embargoed for a period, or only released to other researchers who request it. As it happens, this is exactly how all the other sciences operate, including astronomy. Right now, there are papers being published about things like star formation that are based on data that is not publicly available. Does that mean these ideas are somehow subject to public debate? Probably not, but you can bet that argument would be made if there was some political objective associated with star formation!

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by Chris Peterson » Thu Sep 29, 2011 2:07 pm

Jasev wrote:APOD, I am amazed an astonished. Any amature astronomer can clearly see this photo shows sun from the lower left, and therefore clearly shows these are raised formations...
And just why is an "amature" (sic) astronomer able to make this observation?

Perhaps you don't realize that these structures have been imaged stereoscopically, seen under different lighting conditions, and been measured with radar? There is no doubt that they are depressions. In terms of understanding something like this, I wouldn't make any distinction between an amateur and a professional astronomer, but I'd make a distinction between a good and bad scientist- the former being one who use all the available data to see beyond a simple, well understood optical illusion.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by BMAONE23 » Thu Sep 29, 2011 2:02 pm

neufer wrote:
mikef wrote:
So, here is my message to politically conservative people who doubt that humans are responsible for climate change.
The politically conservative people who really need convincing:
  • 1) don't believe in science & don't trust scientists and
    2) don't care if polar bears starve or if folks in Bangladesh drown.
As to #2 polar bears are thriving and have grown to a population estimated to be 25,000 as of the last survey from an estimated population of 20,000 at the prior survey.

As to number 1
The scientific method states from WIKI
WIKI wrote:Scientific inquiry is generally intended to be as objective as possible, to reduce biased interpretations of results. Another basic expectation is to document, archive and share all data and methodology so they are available for careful scrutiny by other scientists, giving them the opportunity to verify results by attempting to reproduce them. This practice, called full disclosure, also allows statistical measures of the reliability of these data to be established.
In the case of climate science, the data has been viewed as intellectual property and hasn't been freely shared even when requests are made via the Freedom of Information Act.

If there were more openness then the debate might truly be settled but the techniques employed by Climate Scientists to avoid sharing data goes against the very methods they are supposed to stand for as scientists

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by Jasev » Thu Sep 29, 2011 10:16 am

APOD, I am amazed an astonished. Any amature astronomer can clearly see this photo shows sun from the lower left, and therefore clearly shows these are raised formations which have thawed on the raised, sun exposed edges. Notice the small one (bumps) which have not yet thawed, and also notice the dirction of the shadows from the small bumps on the hill tops (the so-called "pit floors"); if they where depressions, their shadows whould have to face the other direction (ie. if these are pits, the "authors" are claiming the sun is at the upper right corner). Also notice the remaining ice on the shadow side of the hills. The linked "pit" photo is indeed a thaw pit, this photo. however, is of a geological formation on Mars, which also has ice evaporation showing.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by neufer » Wed Sep 28, 2011 10:03 pm

mikef wrote:
So, here is my message to politically conservative people who doubt that humans are responsible for climate change.
The politically conservative people who really need convincing:
  • 1) don't believe in science & don't trust scientists and
    2) don't care if polar bears starve or if folks in Bangladesh drown.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by BMAONE23 » Wed Sep 28, 2011 9:41 pm

mikef wrote:I love APOD, but have lurked for years. Something occurred to me when reading the commentary on this one, and I thought it was worth posting.
Having reviewed many different sources of data on humanity-induced climate change on Earth, I am a "believer." If somebody doubted this theory, however, and believes that changes in climate are soley a function of "natural cycles," then Mars might present a viable control planet for study. If climate changes are a function of changes by the sun, or by the solar system passing through regions of differing density ... then there should be similar evidence for this on Mars. Granted, weather patterns and soils are vastly different on Mars - but APOD has posted many photos showing that Mars is not an inert ball of rock without an active atmosphere. Therefore, ice and carbon analysis should be possible on sediment cores.
So, here is my message to politically conservative people who doubt that humans are responsible for climate change. Fund a series of Mars missions to compare a nearby planet without humans! If Mars' climate changes mirror Earth's climate changes, THEN we need an extra-strong economy to weather the upcoming warming cycle. Think of the Mars missions as an investment in your political ideals, or as a bet you can't lose since you're so sure of your ideals. If (on the other hand) there is no evidence of a parallel climate change on Mars (and science for Mars sediment analysis is viable), then we need to alter our behavior.
We don't see the same cyclical variations on Mars as we do on Earth, not because they don't exist but because the dynamics of the atmosphere is vastly different, and so the signatures are different.
Mars atmospheric Density = 0.020 kg/m3
= 0.0012 pounds/cubic ft
Earth atmospheric density = 1.23 kg/m3
= 0.0768 pounds/cubic ft
or 1.5% that of earth.
The martian atmospheric density isn't sufficient to support the same dynamics that reflect certain cyclical climate changes that are presant in the Earth climate signals.

Unfortunately, we haven't had operating climate stations there for more than the same duration as satellite measurements here. We haven't been there (or anywhere else) long enough to determine if the cycles are similar to earth or not.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by neufer » Wed Sep 28, 2011 9:16 pm

NoelC wrote:
I've been studying the shadows at the edges of these things for quite a while now (while waiting on hold on a phone call), and I haven't been able to find it possible to make my mind believe that these are pits.

For one thing, it's FAR easier to believe that the features inside the "pits" are bumps, surrounded by a smooth blanket of snow.
If these were mesas rather than pits they would have been the first places to receive sunlight as the South Pole came out of polar night and, hence, would likely have been the first places to lose their snow cover. Since they are pits the snow cover was protected until later into the season.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by NoelC » Wed Sep 28, 2011 7:09 pm

For example, if one forces oneself to think that the light is coming from the upper-right in this image, and further if we surmise that we're looking at a chasm with fairly steep walls, the silhouette of what appears to be a shadow on the chasm floor does seem to match the edge of the plain above...
Chasm.jpg
However, in this very same image it's a bit difficult to explain how all the little features in the chasm floor could be holes in a surrounding smooth surface, but they would have to be for the light/shadow to look as it does.

-Noel

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by NoelC » Wed Sep 28, 2011 7:00 pm

Heh, you turned the image around so I could be right - thanks. :)

I've been studying the shadows at the edges of these things for quite a while now (while waiting on hold on a phone call), and I haven't been able to find it possible to make my mind believe that these are pits.

For one thing, it's FAR easier to believe that the features inside the "pits" are bumps, surrounded by a smooth blanket of snow.

BUT...

I looked around one of the several hundred megabyte continuous images in this folder:
http://hirise-pds.lpl.arizona.edu/PDS/E ... 3464_0945/

I turned the image so it has the same light orientation as the APOD (180 degrees from neufer's message in the previous post), and if I panned over to where there is no snow the light looks to be coming from the right.
Landscape.jpg
This is a strange, strange landscape indeed!

-Noel

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by neufer » Wed Sep 28, 2011 6:33 pm

NoelC wrote:
neufer wrote:
NoelC wrote:
The light is definitely coming from the left.
Your military left?
I stand by what I wrote. I've looked at this image every way imaginable, and in every case I'm convinced that these features have edges raised over the surrounding floor.

These are not pits but raised features.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by NoelC » Wed Sep 28, 2011 5:58 pm

neufer wrote:
NoelC wrote:
The light is definitely coming from the left.
Your military left?
EDIT: Bah, no more than I was sure I took another look and now it's not so clear...

Looking over one of the very long strips, when I pan over to the mountains, where there's no snow, the light looks to be coming from the right, but I'll be darned if I can make my mind believe that the light is coming from the right when looking at these "pits".

-Noel

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by bystander » Tue Sep 27, 2011 7:52 pm

If you want to study a runaway greenhouse effect, go to Venus.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by mikef » Tue Sep 27, 2011 6:43 pm

I love APOD, but have lurked for years. Something occurred to me when reading the commentary on this one, and I thought it was worth posting.
Having reviewed many different sources of data on humanity-induced climate change on Earth, I am a "believer." If somebody doubted this theory, however, and believes that changes in climate are soley a function of "natural cycles," then Mars might present a viable control planet for study. If climate changes are a function of changes by the sun, or by the solar system passing through regions of differing density ... then there should be similar evidence for this on Mars. Granted, weather patterns and soils are vastly different on Mars - but APOD has posted many photos showing that Mars is not an inert ball of rock without an active atmosphere. Therefore, ice and carbon analysis should be possible on sediment cores.
So, here is my message to politically conservative people who doubt that humans are responsible for climate change. Fund a series of Mars missions to compare a nearby planet without humans! If Mars' climate changes mirror Earth's climate changes, THEN we need an extra-strong economy to weather the upcoming warming cycle. Think of the Mars missions as an investment in your political ideals, or as a bet you can't lose since you're so sure of your ideals. If (on the other hand) there is no evidence of a parallel climate change on Mars (and science for Mars sediment analysis is viable), then we need to alter our behavior.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by itisonlyme » Tue Sep 27, 2011 4:52 pm

reproduce these images. They would be good for a floor tile pattern in a museum.

Re: APOD: Dry Ice Pits on Mars (2011 Sep 26)

by neufer » Tue Sep 27, 2011 4:02 pm

MartinL wrote:
does anyone know how much gold would have to be on Mars so an expedition there would be economically reasonable? :)
In 2003 Moon rocks were valued at about 250 times their weight in gold
so it would be cheaper to return to the moon and collect ordinary rocks.

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