OT Satellite images

There are definitely NRO assets that large floating around but I don't think you really need the resolution they provide to get perfectly useful real-time video for many applications, just a constellation of numerous smaller optics that can be switched in and out as they go in and out of line of sight of the target area, for stuff like real-time bomb damage assessment and watching the helicopters land in an Osama's back yard.

0.5 meter is probably fine, Google Earth's (static) resolution of my neighborhood is around that and I can see my car parked outside and even if I didn't know what car I drove I could probably determine its make and model from that image.

Yes, that's the way that MODIS works. The far IR (and other bands) go right through the clouds and smoke and are therefore visible by a satellite camera. However, John was asking for SMOKE which is only visible during daylight hours.

MODIS data comes from the Terra (EOS AM-1) and Aqua (EOS PM-1) satellites. These are LEO birds that fly at about 700km altitude in near polar (84 and 98 deg), sun synchronous orbits with periods of about 100 minutes. With its sweeping 2,330-km-wide viewing swath, MODIS sees every point on our world every 1-2 days ... So, that's 24 to 48 hrs per image which is not exactly "real time".

Resolution is (mostly) 1km. I don't know which bands or what algorithms are used for fire detection: Looks like: Channel Central Purpose

21 4.0 High-range channel for active fire detection. 22 4.0 Low-range channel for active fire detection. 31 11.0 Active fire detection, cloud masking, forest clearing rejection.

Note that the raw data can be received directly from the satellites:

Having to wait 12 hrs is still not "real time".

That's approaching "real time", but I don't think California is ready to have its own satellite.

Yes, but they're getting better. For example GEOS-16: I don't want to download an original TIFF file, but I think I might be able see a regional size fire in the photo.

The North Fire is currently about 700 acres. 700 acres = 2.83 sq-km. Assuming a square footprint, 1.7km on a side. With 1km resolution, the fire would be 4 pixels out of 100Mpixels. VIIRS can do a little better with 750m resolution.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

The local air quality monitors (how do they work?) track the smoke plume pretty well.

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John Larkin   Highland Technology, Inc   trk 

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

Can Hubble take pictures of Earth? The surface of the Earth is whizzing by as Hubble orbits, and the pointing system, designed to track the distant stars, cannot track an object on the Earth. The shortest exposure time on any of the Hubble instruments is 0.1 seconds, and in this time Hubble moves about 700 meters, or almost half a mile. So a picture Hubble took of Earth would be all streaks.

The solution to that is to have the "film" or imager move at the same speed and in the same direction as the ground, thus keeping the image stable. That's the way aerial cameras and the early Keyhole (KH-9) film return satellites operate: More:

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Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Just below the "See up to date air quality" button is the "What is air quality data?" button. It points to the NOAA HRRR site at: Zoom in to the fire area. Click on "Near Surface Smoke". It should be the same as the SF Chronicle image. Try the direction arrows in the lower left.

Since the SF Chronicle gets its data from HRRR, you might get slightly quicker smoke updates from the HRRR site.

The original real time data comes from the Visible Infrared Imaging Radiometer Suite (VIIRS) sensor on the Suomi National Polar-orbiting Partnership satellite.

There seem to be some bugs in the HRRR "experimental" web page. I've been trying various features and found a few combinations that result in an insane looking smoke picture. The problem is that the only way I've found to recover is to refresh the URL, which causes everything to reset to the original starting point.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

The Google Earth images when you zoom in and see your car are most likely aerial photography and not satellite imagery. They use a combination of both along with GIS data to pull off that Google Earth stuff.

Hubble i essentially a KH-11 spy satellite turned towards the sky. Both have a main mirror diameter of 2.4 m, which determines the diffraction limited resolution. Of course, the atmospherics instability limits the spy satellite resolution.

At least the KH-11 was on a polar orbit, so one good pass once a day. Apparently for this reason the SR-71 spy plane was taken out of retirement to get pictures faster.

I heard* that the military had a 'hubble' first.

George H.

*Neil DeGrasse Tyson

Nah, it's WorldView/Ikonos, Ikonos could provide commerical 1m resolution way back in '99, the recent WorldView satellites claim 0.3m for public consumption, and can probably do better than that, down to

50cm maybe.

That's a great depiction of the smoke plume, except that it was all wrong. The smoke was actually blowing to the east.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics

According to the book "The Hubble Wars" by Eric J. Chaisson, the development of the military spy satellites and the non-military Hubble space telescope did not involve any technology exchange. The military had the benefit of some screwups prior to the perpetually delayed Hubble launch to learn from their mistakes. Such experience was a well guarded military secret. For example, the cantilevered mounting of the solar panels was known to cause the solar panels to "flap" every time they transitioned from hot to cold. The amount of "flap" was insignificant for conventional satellites, but a serious problem for a telescope, which requires very good stability.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Hubble was "on-the-books", NRO stuff is "off-the-books", open technology exchange makes it harder to disguise where the money is going. that is to say it might involve regular accountability to elected officials in Congress. which they aren't big into.

"it's our rainy-day fund"

snipped-for-privacy@yahoo.com wrote in news:a98abfe2-9aa9-4d33-b43d- snipped-for-privacy@googlegroups.com:

Burn all of its sensors and image planes to a crisp.

DemonicTubes wrote in news: snipped-for-privacy@googlegroups.com:

The very first set of this data was taken by NASA back in the late '70s and early '80s. It was done at near noon time from a Lear jet flying over at 40k feet. I have the NASA Laser disc (or did have it). It had sat imagery of the entire planet, but the US major cities had overfly shots of pretty high resolution.

ebay has it:

The entire "Space Archive" series from NASA was the best stuff available back then.

snipped-for-privacy@downunder.com wrote in news:d060pdp6avslbpvps2av50d1k4h6uuepqt@

4ax.com:

Maybe decades ago after some first "retirement", but it has been down since the "retirement" of recent years and will be for good.

The maint costs much less the runtime costs are huge. We get much better res stuff from LEO device you may or may not even know of. And drones! The big bird flies too fast to achieve what we can get from the slower fly- overs.

I doubt seriously that ANY are operating at all.

Interesting, thanks. Someone mentioned the KH-11.

George H.

That's quite possible in the hills, which tend to have rather strange wind patterns. You can see these wind patterns using Weather Underground's map of the area, selecting nearby weather stations, and checking their wind direction history: I don't know where your cabin is located, so I just searched for Truckee and picked a likely station in the fire area: At 0834 PDT (now), it shows 2kt from the SW, which matches the satellite smoke map[1]. Clicking on the history tab and selecting yesterday's date: the wind direction in the table is mostly from the W or SSW, which again agrees with the smoke map. (You can click on the graph, hold the mouse button down, and drag the graph to the right to show afternoon times on the graph). The arrows on the graph show the afternoon winds as mostly from SSW, but also include some turbulence and changes in direction. However it never showed any time where the wind was coming from the east.

I can get a better picture of what happened if you could identify a weather station that is located fairly close to your cabin.

[1] Wind direction is most commonly specified as the direction FROM which the wind it blowing. You can see that by looking at any traditional arrow style wind vane, where the arrow points into the wind. It's a standard established by mariners, who are interested in which way their vessel is going to be driven by the wind. (Yes, I know I slipped up early in this thread).

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

I use this a lot,

it is very good in displaying and predicting wind, rain, temperature to within an hour. Very accurate. Boomark it in your browser for your location and it is maybe all you need.

I take it back...It is a combination of satellite and aerial photography.

That WorldView-3 is impressive. Nice images! I wouldn't be able to determine make and model of a car from that, but damn near. They are probably running into the limit of what they can do through all that atmosphere at this point.