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The quality of the photographs from the moon always grabs me

why?

photography had already been around for 100+ years at the time. the astronauts had hasselblads and were shooting on the best medium format film available.

http://history.nasa.gov/alsj/a11/a11-hass.html

Interesting. It's strange that the maximum temperature the skin of the X-15 reached was around 1300 F.

http://history.nasa.gov/SP-60/ch-5.html

> The bottom line is that government is moving slowly on cataloging NEOs

NASA's NEO program catalogs bodies as soon as the data comes available.

There are 7 programs besides NASA searching and/or cataloging (they're listed on JPL's site: http://neo.jpl.nasa.gov/programs/ ). When one team gets data, they all share in it. The programs are only as slow as the data. As for US government, 5.5 of the 8 programs are US based (one in Italy, one in Japan, one joint US-Aussie).

> NASA has yet to allot funds to the project

The NASA NEO program is run from JPL.
JPL is managed by Caltech for NASA.
NASA pays JPL to do so.
The 8 people in the NEO program appear to be all NASA employees, or at least from Caltech or other universities, paid by NASA (directly via payroll or JPL funding, or indirectly via funding to their parent university) to work there. There is no need to have funding dedicated explicitly to the program if existing funding is available to operate the office under other funding headings.

The government is perhaps not moving as fast as it could in data collection if it funded a dedicated telescopy program directly, but that doesn't imply the cataloging is slow.

The bottom line is that the article is correct in that private concerns are providing funding for or operating search and/or cataloging operations, but that's all. The assertions regarding cataloging being slow and lack of funding are unfounded.

Of course any government funded program will tell you there's a "lack" in terms of not enough (as opposed to an absence), because they'll get their funding cut if they don't show the need. The output from this program indicates it's operating its cataloging project at the speed necessary to keep up with the data.

The interesting thing is, lately NASA has been primarily using relatively common digital SLR cameras. I'm not sure what modifications, if any, they've made. They do have thermal protection covers for EVA's, which are left off for photography from inside the station or shuttle.

Most of the photos seem to be taken with Kodak DSC760's, a 6 MP camera dating back to 2001 that is limited to ISO400. Lately they've also started to use the newer 12 MP Nikon D2Xs.

Granted, these are nicer than most ordinary Joe's own, but they are nothing extraordinary. However, just look at the detail they get during shuttle dockings at the ISS.

The interesting thing is, lately NASA has been primarily using relatively common digital SLR cameras. I'm not sure what modifications, if any, they've made. They do have thermal protection covers for EVA's, which are left off for photography from inside the station or shuttle.

Most of the photos seem to be taken with Kodak DSC760's, a 6 MP camera dating back to 2001 that is limited to ISO400. Lately they've also started to use the newer 12 MP Nikon D2Xs.

Granted, these are nicer than most ordinary Joe's own, but they are nothing extraordinary. However, just look at the detail they get during shuttle dockings at the ISS.

Good observation.

This is what I see in the photo: if you look at the front right wheel, you'll see an S-shaped trench leading away from it, going off-camera in the bottom-right of the image. You'll also notice that at the bottom-right of the image a footprint appears which seems to have significantly altered the trench. Actually it looks like it filled it in.

The moondust is very light and prone to redistribution (that's the whole point of TFA, in fact), so perhaps just stepping near a tire-track is enough to fill in the trench (after the dust settles)? If so, then when you look at the back-right wheel, you'll see that there are footprints there which may have disturbed the ground and filled in the trench from the wheel (especially since he would have had to walk all over the place near that wheel while performing the repair). Actually there are some faint indications of where a track may have once been.

I'm certainly no expert in these kinds of things, but it seems to me that working near the vehicle would quickly disturb any tracks, because of how light the rocks and dust are on the moon.

Yup. Swedish engineered camera with German lenses. Pretty much the best of both worlds. For your information.

The Lunar Surface Journal over here: (more specifically on the Apollo 17 page of course)
http://www.hq.nasa.gov/office/pao/History/alsj/frame.html

Craploads of imagery from all surface missions, full transcripts, and audio. :)

All good except that the universe is flat

This is the default. Radiation from the sun and a zero pressure, zero gravity environment is enough to kill any microbes on our spaceships.

Sorry, but reality says different.

The 50-100 organisms survived launch, space vacuum, 3 years of radiation exposure, deep-freeze at an average temperature of only 20 degrees above absolute zero, and no nutrient, water or energy source.

Known near misses are published.

Check out Orbital Debris Quarterly News at http://orbitaldebris.jsc.nasa.gov/newsletter/newsletter.html They have back issues in pdf

It certainly going to be a challenging project to pull but that's no reason to shy away from it. While NASA Learning Technologies is not funding development, the expectation is that the developer will be able to generate a revenue stream from the game. A non-reimbursable space act agreement will give the developer a lot more flexibility that any procurement vehicle would. LT is planning to fund educaiton and subject matter experts to work with the developer to enhance the game and it's education impact. But fundamentally the development partner will need to build a game that is compelling and profitable or no education value can come from it. Daniel Laughlin NASA Learning Technologies http://ipp.gsfc.nasa.gov/mmo

This statement was widely quoted to discredit climate change/global warming but it's really just a case of cherry-picked data. It was anomalously hot in 1998, and it's deliberately mis-leading to make generalized statements from anomalous data.

It is accurate to claim that global temperatures in every year 1999-2007 have been cooler than the temperatures of 1998*. However, stating that the temperatures "have not risen since 1998" implies that temperatures have been cooling since 1998, which is not true. Temperatures from 2000 through 2005 certainly rose every year.

Here's some pretty graphs to back up my statements.

* It depends on the data set (land, ocean, atmospheric, US only etc). For certain data sets, 2005-2006 was hotter than 1998, but on average 1998 wins.

I don't care which side of the argument you're on, I just hate it when someone deliberately mis-represents the data to support their side.

A detailed look at this can be found in this link from Nasa on the topic of moon fountains, which is basically the exact same thing under a different name.

Sagan ... really didn't involve himself directly in active research in the last decades of his life.

"So far, this is pure speculation: no man has been on the moon" Fixed.

Just one example of what might go on that we can't see with regards to lunar dust storms. Took me all of a few seconds to find and there looks to be a lot more to read. Google is your friend.

Alas, the energy requirements are tough. About the only option is some form of nuclear propulsion -- though there are a number of interesting varieties of nuclear. The original Orion concept is an interesting one -- I've been reading some of the original cost estimates (pdf), and they get quite interesting -- $3.30 per kg for a Jupiter mission, assuming reasonable costs for the plutonium. (Not 2008 dollars, and I don't know what the actual price of plutonium is these days.)

More modern interesting proposals include the nuclear salt-water rocket and the fission fragment rocket. Of course, neither of these is particularly well suited to in-atmosphere work, and you have to be careful where you point the exhaust (but since it's moving faster than solar escape velocity, that's a relatively simple problem).

Contrary to recent press reports, NASA offices involved in near-Earth object research were not contacted and have had no correspondence with a young German student, who claims the Apophis impact probability is far higher than the current estimate.

This student's conclusion reportedly is based on the possibility of a collision with an artificial satellite during the asteroid's close approach in April 2029. However, the asteroid will not pass near the main belt of geosynchronous satellites in 2029, and the chance of a collision with a satellite is exceedingly remote.

NASA denies this report: http://www.nasa.gov/home/hqnews/2008/apr/HQ_08103_student_asteroid_calculations.html#maincontent

"This is within the distance of Earth's geosynchronous satellites. However, because Apophis will pass interior to the positions of these satellites at closest approach, in a plane inclined at 40 degrees to the Earth's equator and passing outside the equatorial geosynchronous zone when crossing the equatorial plane, it does not threaten the satellites in that heavily populated region. " From here.

NASA actually has a page describing some of their calculations about this asteroids position. http://neo.jpl.nasa.gov/apophis/ In it "It was found that small uncertainties in the masses and positions of the planets and Sun can cause up to 23 Earth radii of prediction error for Apophis by 2036." "The study did NOT compute new impact probabilities. This is because key physical parameters (such as mass and spin pole) that affect its trajectory have not yet been measured and hence there are no associated probability distributions." NASA doesn't really know. I call BS on the article.

The NASA NEO site gives 21M tons, which is much more plausible.

The many observations are what was involved in the NASA JPL orbit determination. My impression is he just said "suppose it hits a satellite, what will that do to the orbit?" and then ran those numbers plus the JPL numbers through the simulator.

I also get the impression the 1/450 number is 1/450 odds of a collision with Earth, *if* it hits a satellite.

I don't know how many satellites there are in geosync, but I'm pretty sure you're right that it's less than 40,000. That might be about right for total satellites, though -- not that that's all that relevant.

I too would like to see an official NASA comment on this.

The NASA NEO site gives 2.1E10 kg, or 2.1E7 tons -- 21M tons, unless I've screwed up the units somewhere or that site is wrong (both possible :) ).

The same site gives vImpact for Apophis at 12.59km/s. I haven't looked at the approach trajectory in detail, but geosynchronous orbit is only 3.07 km/s, so the relative velocity is dominated by Apophis (moving at less than 12.59, but more than the 5.87 km/s vInfinity; I'm too lazy to work out the exact number). It's orbital velocity wrt the Sun is about the same as Earth's, or 30 km/s -- so the 5-10 km/s collision velocity is 15-30% of its orbital velocity, roughly.

It's a small effect, to be sure, but it has a very, very long lever to work with. I'd be reluctant to say he's wrong without actually doing the math myself in far greater detail than either of us has done here.

Yeah, even with the distortion, it's still no better than about 50% to hit the Atlantic (5 time zones = 75 degrees. sin(75/2) = 0.53).

As for the small change, the asteroid is actually ~20 billion tonnes, so its about 5E9 times more massive than a satellite. There is info about its orbit in this table correctly. I haven't done the calculations, but my guess is that the ratio of its mazimum possible collision velocity relative to a typical geostationary satellite to its orbital velocity is very small, but lets say 5% (almost certainly a huge over-estimate). That means that the effect of the collision on its orbital velocity is going to be on the order of 1E-11. Now, that's well inside the the errors on the table, so yes, small changes can be amplified, but a change that is significantly smaller than measurement error is not going to change any predictions for where this thing ends up.

The Atlantic ocean is about 75 degrees across (5 time zones). sin (75/2) = 0.53, so, as a rough estimate, even if we did know the exact time, one couldn't say that it would hit the Atlantic with much better odds than 50%.

Interestingly, I've been playing around with this applet and it's not predicted to come anywhere near earth in 2036. It comes within 0.0022 AU in 2029, but no closer than about 0.1 AU in 2036 (or 2035 or 2037, for that matter).

It would seem surprising if a collision with a satellite that's 0.00000005% of the asteroid's mass is going to change that enough for it to hit the earth. The whole article is bullshit.

And this:
http://neo.jpl.nasa.gov/cgi-bin/ip?2.2e-05

May I add that NASA, at least currently, doesn't even mention this? http://neo.jpl.nasa.gov/apophis/ Where do they get this info, if this isn't anywhere on NASA?

True but not really relevant. Unless the readership of Slashdot is wider than I'm aware of the only frame of reference of relevance is that of the Earth. Hence that is the only frame you need to concern yourself with is that one.

Remember that the Earth frame is arbitrary. Although relativity stipulates that there is no privileged frame, strictly speaking there is only one intertial frame which is at rest with respect to the cosmic microwave background radiation; if the Earth were at rest in it then we would see a sky with a uniform temperature in all directions. Instead we can observe a dipole moment in the sky's CMB spectrum consistent with motion at 380 km/s toward the direction of Virgo. The inertial frame of the black hole would also be worthy of consideration. But of course this is all just Slashdot nitpicking, you do your calculations in the Earth's frame because you want your result to come out in Earth proper time, and realistically this means you don't do anything different.

Not actually true: they are larger at those relative speeds but are certainly present and noticeable at far lower velocities e.g. atomic clocks on Concord, GR corrections to GPS satellite clocks etc.

Those effects are negligible with this level of approximation. Basically everything can be considered to be at rest; you guys are making this way harder than it is. This is a simple problem of geometric optics. We're seeing this glowing cloud, with a region 10 light years across, brightening and darkening within the space of 5 light years. That's very hard to explain as anything other than a light echo from a source nearby that must have been bright, and small, and rapidly varying in brightness. And look, there's this supermassive black hole sitting here 300 light years away. You don't have to be Einstein to figure this one out.

The star V838 Mon is a good example of a light echo. This star emitted a huge flash in 2002 that made it the brightest star in the galaxy for a couple months. Then it dimmed to a normal brightness. Once it did, starting in mid-late 2002, we started to see a huge reflection of the flash begin to expand out from the star as it lit up the gas and dust in the vicinity. At any given time we see a glowing sheet of gas shaped like a paraboloid open towards us with the star at its focus, and every year this paraboloid gets bigger. Now that it's 2008 this thing has become a Firefox logo 12 light years wide that continues to expand outward in all directions at the speed of light.

NASA hasn't updated their page on Apophis yet. http://neo.jpl.nasa.gov/risk/a99942.html

I call bullshit on this story. You can clearly see that NASA hasn't "agreed" at all.

Mad Cow Disease for Robots?

• http://marsprogram.jpl.nasa.gov/msl/technology/tech_edl_mardi.html
• http://www-robotics.jpl.nasa.gov/applications/applicationArea.cfm?App=3
• http://www-robotics.jpl.nasa.gov/tasks/showTask.cfm?FuseAction=ShowTask&TaskID=84&tdaID=999986
• http://www-robotics.jpl.nasa.gov/publications/Andrew_Johnson/aejJGCD2002.pdf

• http://marsprogram.jpl.nasa.gov/msl/technology/tech_edl_mardi.html
• http://www-robotics.jpl.nasa.gov/applications/applicationArea.cfm?App=3
• http://www-robotics.jpl.nasa.gov/tasks/showTask.cfm?FuseAction=ShowTask&TaskID=84&tdaID=999986
• http://www-robotics.jpl.nasa.gov/publications/Andrew_Johnson/aejJGCD2002.pdf

• http://marsprogram.jpl.nasa.gov/msl/technology/tech_edl_mardi.html
• http://www-robotics.jpl.nasa.gov/applications/applicationArea.cfm?App=3
• http://www-robotics.jpl.nasa.gov/tasks/showTask.cfm?FuseAction=ShowTask&TaskID=84&tdaID=999986
• http://www-robotics.jpl.nasa.gov/publications/Andrew_Johnson/aejJGCD2002.pdf

• http://marsprogram.jpl.nasa.gov/msl/technology/tech_edl_mardi.html
• http://www-robotics.jpl.nasa.gov/applications/applicationArea.cfm?App=3
• http://www-robotics.jpl.nasa.gov/tasks/showTask.cfm?FuseAction=ShowTask&TaskID=84&tdaID=999986
• http://www-robotics.jpl.nasa.gov/publications/Andrew_Johnson/aejJGCD2002.pdf

I still like the old Solar System Exploration website better. It's easy to search for past, present, and future missions by name, target, or decade. Plus, it knows about Eris, unlike the new site.

I still like the old Solar System Exploration website better. It's easy to search for past, present, and future missions by name, target, or decade. Plus, it knows about Eris, unlike the new site.

I still like the old Solar System Exploration website better. It's easy to search for past, present, and future missions by name, target, or decade. Plus, it knows about Eris, unlike the new site.

Funny how the Small Bodies of the Solar System page doesn't breathe a word about Eris. Nor does their site search return any results on that term.

Seems like some people haven't digested Pluto's demotion yet ...

Looks like they are using Plone as a CMS as well as for deployment, since good ol' /ZopeTime works :P

http://nasascience.nasa.gov/ZopeTime

NASA/CR-2001-210866, Personal Electronic Devices and Their Interference With Aircraft Systems

Because CFCs help the breakdown of O3 into O2, but do not themselves get broken down in the reaction. They can persist in the upper atmosphere for fifty or more years. That's why the ozone hole has not suddenly repaired itself - because there are still plenty of CFCs around where they shouldn't be.

Seriously, I've been reading about this issue since the British Antarctic Survey said "hey guys, we've got a problem".

"The discovery by the British Antarctic Survey of the Antarctic ozone hole provided an early warning of the dangerous thinning of the ozone layer worldwide, and spurred international efforts to curb the production of CFCs. The provisions of the Montreal Protocol of 1987 on Substances that Deplete the Ozone Layer have been revised and strengthened and are being followed by virtually all UN Member states. There is a reasonable prospect that the Antarctic ozone hole will permanently repair itself, but not until around 2070." http://www.antarctica.ac.uk/about_antarctica/geography/ozone.php

If you don't like wikipedia, here's NASA: "The ozone layer protects us from the Sun's harmful ultraviolet radiation and is vital to life on Earth. Depletion of this protective layer can be harmful to the health of humans, plants and animals. Human-produced pollutants called chlorofluorocarbons (CFCs) emitted into the atmosphere are the main cause of ozone loss. Scientists first discovered dramatic depletions in the ozone layer in 1985. Although recent initiatives by governments around the world have stopped the production of CFCs, damaging chemicals still persist in the upper atmosphere." http://www.nasa.gov/vision/earth/lookingatearth/arctic_air.html

Some people may suggest abandoning your keyboard and going outside to observe this "sun". I recommend that you visit http://umbra.nascom.nasa.gov/images/latest.html instead. Much less effort required. :)