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Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

nytimes.com

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Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#31

Post by callesgg »

bargl wrote: post #3

So my first thought was (will this replace the doves by space labs). Which was an earlier story on HN. https://news.ycombinator.com/item?id=8158295 It won't because these are geostationary satellites (if I read the post correctly). So you'd need at least 3 of these to get a good image and that's not even considering some of the bigger issues with this. I also don't think the resolution is on par. But the images will…

the resolution difference is quite big. Planet labs satellites captures with something like 1mx1m resolution.

This satellite has a resolution of about 500mx500m

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#33

Post by vlasev »

SiVal wrote: post #23
Syrup-tan wrote: post #19

I wrote a simple shell script[0] to scrape and output the latest image. It uses the tiles from their online satellite map[1], and can output images in increments of 1x1, 2x2, 4x4, 16x16 tiles (each tile being 550px by 550px). Here is an example with 2x2 [2] If you have any suggestions or bugfixes, feel free to fork or comment. EDIT: Also works for a single tile[3], also clarity. [0] https://gist.github.com/Syrup-tan/…

I wish there were a pair of these satellites separated by a couple thousand miles/km, so we could view these images with next-gen, hi-rez VR goggles and see the surface and cloud topography with enhanced depth.

Let's do a sanity check on this.

Cloud height is at about 60,000 feet maximum (in the tropics http://www.srh.noaa.gov/jetstream/clouds/height_max.htm). Let's be generous and say this is 20 km maximum height.

Earth's diameter is 12742 km. The clouds are about 0.15 % of this size, relatively speaking. The full images are about 11k by 11k, so we can say that 1 px is roughly 1 km. This means that the clouds will be on the scale of 20 pixels, roughly.

You know what, this might actually work.

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#34

Post by patrickmclaren »

Animats wrote: post #6

Nice. Japan needs better weather data; too many hurricanes and too much coastal development. From geostationary orbit, the resolution has to be low, but it's always on. The US has two geostationary weather satellites, which are usually parked roughly over Panama and Hawaii. Neither has good coverage of Japan. Korea's COMS satellite does, though. China has several, including one that's usually pointed roughly at Taiwa…

I didn't realise they were lacking in weather data. Seeing tangentially related projects like their supercomputer Earth Simulator Project [1] led me to (falsely it seems) believe they were likely also sufficient in that area.

Beginners question - does their inclination (prohibitively) affect the efficiency of lower orbit weather sats?

[1] https://en.m.wikipedia.org/wiki/Earth_Simulator

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#35

Post by tomkwok »

Here is a 11000x11000 = 121 million pixel 'full disk' image [1] (lower resolution at [2]) captured at 0340 UTC on 7 July 2015 by the Himawari-8 satellite, which I found on a blog post [3]. Real-time images from the weather satellite can be found here [4].

[1]: http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2015...

Mirror of [1]: http://d-h.st/cgHl

Warning: the JPEG file[1] is ~ 70MB in size.

[2]: http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2015...

[3]: http://cimss.ssec.wisc.edu/goes/blog/archives/18804

[4]: http://ds.data.jma.go.jp/mscweb/data/himawari/sat_img.php?ar...

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#36

Post by blackguardx »

callesgg wrote: post #31
bargl wrote: post #3

So my first thought was (will this replace the doves by space labs). Which was an earlier story on HN. https://news.ycombinator.com/item?id=8158295 It won't because these are geostationary satellites (if I read the post correctly). So you'd need at least 3 of these to get a good image and that's not even considering some of the bigger issues with this. I also don't think the resolution is on par. But the images will…

the resolution difference is quite big. Planet labs satellites captures with something like 1mx1m resolution. This satellite has a resolution of about 500mx500m

I think it is actually 5m. 1m gets pretty close to spy satellite territory. The planet labs lens only has a focal length of <30cm.

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#37

Post by shpx »

SiVal wrote: post #23
Syrup-tan wrote: post #19

I wrote a simple shell script[0] to scrape and output the latest image. It uses the tiles from their online satellite map[1], and can output images in increments of 1x1, 2x2, 4x4, 16x16 tiles (each tile being 550px by 550px). Here is an example with 2x2 [2] If you have any suggestions or bugfixes, feel free to fork or comment. EDIT: Also works for a single tile[3], also clarity. [0] https://gist.github.com/Syrup-tan/…

I wish there were a pair of these satellites separated by a couple thousand miles/km, so we could view these images with next-gen, hi-rez VR goggles and see the surface and cloud topography with enhanced depth.

I've always wondered if https://xkcd.com/941/ actually works and if anyone has done it yet

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#38

Post by eridius »

lsjroberts wrote: post #28
InclinedPlane wrote: post #20

Earlier quoted context omitted.

Privacy is on a sliding scale. There are certain assumptions we rely on when we go out in public. Imagine, for example, some future where you were effectively under constant surveillance when in "public". Where your every action, every movement, every utterance was recorded, categorized, transcribed, data mined, and then put into a feed that anyone could subscribe to. That's what the complete absence of public privac…

Yeah, living in London you have several cameras looking at you permanently. You can see a bunch of them via the TFL api as well.

But, AIUI, those cameras aren't networked together. They're all owned by different people. TV shows like Torchwood that show some agency tracking someone across the city using CCTV are showing something that can't possibly happen in real life, because there is no one centralized authority (or even handful of authorities) that have access to most of those cameras. Not to mention the cameras themselves are just video, and not particularly stellar quality at that.

Of course, I could be wrong, maybe someone in London really can track someone across town using the CCTV cameras, but the above is what I understand from what other people have explained in the past.

Re: Japan’s New Satellite Captures an Image of Earth Every Ten Minutes

#40

Post by rktjmp »

Animats wrote: post #6

Nice. Japan needs better weather data; too many hurricanes and too much coastal development. From geostationary orbit, the resolution has to be low, but it's always on. The US has two geostationary weather satellites, which are usually parked roughly over Panama and Hawaii. Neither has good coverage of Japan. Korea's COMS satellite does, though. China has several, including one that's usually pointed roughly at Taiwa…

Why does geostationary orbit infer low resolution? Or do you mean "from orbit" in general?
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