MSG-4, Europe’s latest weather satellite, delivers first image | Hacker News Reader

MSG-4, Europe’s latest weather satellite, delivers first image

esa.int

70 pointseplanit34 comments

https://www.flickr.com/photos/eumetsat/19667653813/sizes/l

"Original (16672 x 9378)" :)

Will not load :)

Original size crashes my chrome tab :)

when it starts loading the image right click on the image and then Save As. Chrome will crash but the picture will be downloaded(30MB+)

Direct link: https://farm1.staticflickr.com/265/19667653813_94a68f5644_o....

Preview on OS X works surprisingly well with a giant JPEG like this. It seems like its doing clever stuff(tm) when decoding the image for various zoom levels.

Chrome should (I mean.. it doesn't, but it really should) do this as well.

Interesting that it crashes yours, works fine for me (Chrome 44 on Debian unstable). The tab uses around 800MB while the picture is loading and then immediately drops to ~160MB and further to ~90MB after a while. Scrolling is quite laggy, though.

For comparison, [1] has full-resolution (14400x12001) imagery from the GOES [3] satellite that has a view of the US West Coast. And similarly, [2] for the East Coast.

[1] ftp://goes.gsfc.nasa.gov/pub/goeswest/fulldisk/fullres/vis/ [2] ftp://goes.gsfc.nasa.gov/pub/goeseast/fulldisk/fullres/vis/ [2] https://en.wikipedia.org/wiki/Geostationary_Operational_Envi...

Is there a (rather) easy way to obtain the MSG-4 images using SDR like it is possible for NOAA and Meteor-M N2 (http://www.rtl-sdr.com/rtl-sdr-tutorial-receiving-noaa-weath...)?

Go to http://www.eumetsat.int/ and follow links on data delivery. The eumetcast system lets you pick up data using normal satellite TV hardware but you're not picking it up direct from, e.g. MSG-4. It is broadcast via another satellite much as for, e.g. a TV signal. You can also get some data via the Internet.

Meteor-M N2 is in polar orbit, so you may need a fancy antenna to receive MSG, which is in geostationary orbit (don't quote me on this, but this reddit user has the same suspicion https://www.reddit.com/r/RTLSDR/comments/23pquc/can_you_rece...).

But EUMETSAT (contractor of MSG-4) has EUMETcast for distributing the images: http://satsignal.eu/wxsat/atovs/index.html That works over DVB though, which would be disappointing for you since you wanna talk to satellites.

There is a library for decoding the proprietary formats: https://sourceforge.net/p/meteosatlib/wiki/Home/

The linked Reddit thread has this very nice answer: https://www.reddit.com/r/RTLSDR/comments/23pquc/can_you_rece...

Live stream encrypted and six hour delay for unencrypted, am I reading that right?

doh! I just asked a similar question without seeing yours :)

To the best of my knowledge, this thing takes snapshots of its viewing field every 15 minutes. That'll be tremendously helpful for calibrating atmospheric and ocean models of ecosystem dynamics.

And Japan recently launched another satellite with the same interval and resolution!

Similarly, the South Koreans have a geostationary satellite (GOCI) [0]. It's sampling interval is a bit lower (3 hourly) but has a high spatial resolution (500m).

[0] https://en.wikipedia.org/wiki/Geostationary_Ocean_Color_Imag...

The sampling interval of the Japanese and the European satellite is really interesting, though, because it allows to view more than half of earth in 15min intervals. We can see live the movement of clouds and typhoons around the earth.

This is really powerful.

Depends on the resolution and scan area you're talking about. I think the .5km can go off every 15min. But the 2km can go out every 5.

But that's nothing. IIRC, the Mesoscale (a 1000km x 1000km box somewhere in the hemisphere) can go out every 30s. On top of that, I believe you can snap a Meso without interrupting normal operations.

Here in the US, the idea of getting a snapshot of a Tropical Wave out every 30s during, say, hurricane season is very, very exciting.

The linked page shows an image of the complete Earth. Is that really the viewing angle of this satellite?

Yes, it is in geostationary orbit.

So it's not a composition? It's exactly 10am UTC everywhere in this picture?

I think what iso8859 is trying to say is that a geostationary orbit is very far, so it's still a narrow angle, as illustrated here:

http://stream2.cma.gov.cn/pub/comet/SatelliteMeteorology/GOE...

No composition required.

Uhhh....no?

Anybody know what frequency + modulation this thing broadcasts? Any hope for a little radio + twin helix antenna to pick up images?

While joesoap's comment on the article page is hilarious, it made me think - are there any technological issues to providing (nearly) real-time low-res video feed? It would be scientifically useless, so this is more of a theoretical question about the tech/physics involved.

Am I imagining it or does North Africa look dryer than it did in Apollo era photographs?

If you check the caption you'll see that it's an infrared color image (except for the blue channel, which is in red 600um). Therefore the picture is probably more sensitive to the surface temperature variations, and, consecutively, North Africa might look dryer indeed.

This.

Also, the precipitation since the late sixties in the area surrounding the Saharan desert has been below average, leading to desertification (http://oceanworld.tamu.edu/resources/environment-book/desert...):

> Years of above average rainfall from the 1950s to the 1970s, were followed by drought in the sahel starting in the late 1960s. The drought has had a devastating impact on this ecologically vulnerable region and was a major impetus in the establishment of the United Nations Convention on Combating Desertification and Drought.

So, during the 1960:s North Africa probably looked extra lush because it had experienced over a decade of above-average precipitation.

This has to be the sharpest picture of earth I have seen...

You can see a lot of jagged edges on the left side of the higher resolution image: http://www.esa.int/var/esa/storage/images/esa_multimedia/ima...

Good catch! But I think the jagged edges there result from an arbitrary clipping of the brightness values, done to remove the "noise" pixels, i.e. to make the space look darker. If that's the case, it isn't the resolution that's to blame - just a post-processing (for public release) issue.

Chrome crashes on me when I try to open original photo

Really, the weather satellite delivered a 1.4M JPEG?

No, it delivered a 34M JPG https://farm1.staticflickr.com/265/19667653813_94a68f5644_o....

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