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Loss of key US satellite data could send hurricane forecasting back 'decades'

(www.theguardian.com)
312 points trauco | 1 comments | 29 Jun 25 17:39 UTC | HN request time: 0.207s | source
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declan_roberts[dead post] ◴[29 Jun 25 18:28 UTC] No.44415221[source]▶
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lupusreal ◴[29 Jun 25 19:23 UTC] No.44415600[source]▶
Good grief. American KH-11 electro-optical spy satellites have 2.4 meter primary mirrors and orbit at ~300km or less. Ease yourself off the anti-Musk subreddits or wherever you're getting this incoherent nonsense.
replies(1): >>44416255 #
mh- ◴[29 Jun 25 20:39 UTC] No.44416255[source]▶
Additional context for those unfamiliar: KH-11s are thought to weigh 30-40 thousand pounds (~20k kg).

The mirror itself would dwarf anything launched for Starlink, multiple times over.

replies(1): >>44419068 #
declan_roberts ◴[30 Jun 25 03:34 UTC] No.44419068[source]▶
Starlink is 65x closer to earth. If a geostationary satellite was 1 km away, Starlink would be ~15 meters.

Dramatically different scale.

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mh- ◴[30 Jun 25 03:40 UTC] No.44419118[source]▶
Thanks for the extra context, that's helpful.

How big would the optics on a satellite in Starlink's orbit need to be to achieve similar clarity, then?

replies(1): >>44419397 #
1. defrost ◴[30 Jun 25 04:32 UTC] No.44419397[source]▶
A little bit bigger, the starlink sats have a uniform height, the optical spy sats with the big mirrors have a similar mean orbital height but are in elliptic orbits that come in closer, then further away. The best photos are taken closer to the earth than a typical starlink sat is.

The above comment about geostationary orbits is confused .. the spy sats with mirrors relay their data out to geostationary relay sats and then back to earth ground stations.

If you're curious you can read more in the wikipedia link (and other references) I linked in a peer comment.