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End of an era: Landsat 7 mission takes final images

usgs.gov

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Re: End of an era: Landsat 7 mission takes final images

#31

Post by [deleted] »

Mistletoe wrote: post #30

Frightening how much smaller Lake Mead is now. > How long does Lake Mead have left? Lake Mead has been facing a water crisis for many years. The water level in the lake has been dropping due to the increasing demand for water and the decreasing supply. If the trend continues, the lake could run out of water in the next 10 to 15 years. Great…I was in Vegas last weekend, I guess they’ll just run it until it’s dry. Huma…

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Re: End of an era: Landsat 7 mission takes final images

#34

Post by MostlyStable »

is_true wrote: post #29
bmsan wrote: post #12

Dang, hits home. When I was a senior in high school, I was lucky to able to volunteer under Dr. Eric Brown De Colstoun at NASA Goddard, checking error rates for tree cover estimates using Landsat data^. Many hours that fall spent trudging around parks and forests, looking at the sky through a PVC pipe. It still kind of blows my mind at how much is able to be gained from images where each pixel is 15mx15m of ground-le…

What did you do with the pvc pipe?

if I had to guess, they were going to randomly selected locations, looking at the sky through the PVC pipe (presumably straight up), and seeing if it was obstructed by tree canopy or not, and then comparing to whether or not the satellite said there was tree cover in that location

Re: End of an era: Landsat 7 mission takes final images

#35

Post by kibwen »

Mistletoe wrote: post #30

Frightening how much smaller Lake Mead is now. > How long does Lake Mead have left? Lake Mead has been facing a water crisis for many years. The water level in the lake has been dropping due to the increasing demand for water and the decreasing supply. If the trend continues, the lake could run out of water in the next 10 to 15 years. Great…I was in Vegas last weekend, I guess they’ll just run it until it’s dry. Huma…

The city of Vegas is among the best and most proactive in the country at water preservation and reclamation. Sadly, it still might not be enough. In the 90s they started paying people to tear up their lawns, and more recently they outlawed lawns and started tearing some up forcefully, and last I checked watering grass still accounted for a double-digit percentage of their water budget.

Re: End of an era: Landsat 7 mission takes final images

#36

Post by mmooss »

Yawrehto wrote: post #5

It seems like a lot of these government-owned space things last a lot longer than they're made for. There's Landsat, Spirit, Opportunity, Hubble, the Voyagers, et cetera. It seems to be a pretty steep curve - either they fail on launch or landing or very early, or they far outlast expectations. There seems to be little that meets expectations. I can see lots of failures - space stuff is hard - but why so many things…

Basic consulting: Underpromise, overdeliver. Nobody knows how long a Mars rover should last; NASA perhaps picks a number so low that they can't fail, and then have another narrative about the amazing little robot that kept going, and which makes the investment look great for taxpayers.

Re: End of an era: Landsat 7 mission takes final images

#40

Post by bargle0 »

bmsan wrote: post #12

Dang, hits home. When I was a senior in high school, I was lucky to able to volunteer under Dr. Eric Brown De Colstoun at NASA Goddard, checking error rates for tree cover estimates using Landsat data^. Many hours that fall spent trudging around parks and forests, looking at the sky through a PVC pipe. It still kind of blows my mind at how much is able to be gained from images where each pixel is 15mx15m of ground-le…

Yeah, the scan line corrector broke. Landsat 7 images had these “whiskers” of missing data running perpendicular to the path. For a while there it was just old Landsat 5 and broken Landsat 7.
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