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When a Telescope Is a National-Security Risk

theatlantic.com

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Re: When a Telescope Is a National-Security Risk

#11

Post by BenjiWiebe »

uticus wrote: post #7
nradov wrote: post #5

Some of the language in this article is a bit odd, and appears to reflect a fundamental misunderstanding of satellites and orbital mechanics. The orbits of spy satellites are hardly "irregular", nor can they "shift direction often". Orbits are exactly regular, by definition. Orbital parameter changes do happen but are rare. Even the largest spy satellites have only very limited ΔV capability. And there are no stealth…

> Orbits are exactly regular, by definition. Orbital parameter changes do happen but are rare. How does that match up with [0]? "... a satellite that stalks other satellites, started another relocation move on July 22, leaving its position near ASTRA 4A at longitude 4.8 E and drifting west at 0.9 degrees per day." Do they make this up, or do you and I have a vastly different understanding of "irregular"? [0] https://…

That is interesting. I wonder how many stalking maneuvers it can do before it depletes it's propellant/reaction mass.

Re: When a Telescope Is a National-Security Risk

#13

Post by adgjlsfhk1 »

sinuhe69 wrote: post #12

A telescope that able to see billion light years away can also see satellites in close earth orbits? How incredible is that! How can it shift and change its focus so dramatically? Would not a flyby satellite cover the entire view field of the telescope?

focus isn't an issue because they're both (basically) at infinity. fov isn't an issue because a satellite is much smaller than a galaxy

Re: When a Telescope Is a National-Security Risk

#14

Post by iudqnolq »

nradov wrote: post #5

Some of the language in this article is a bit odd, and appears to reflect a fundamental misunderstanding of satellites and orbital mechanics. The orbits of spy satellites are hardly "irregular", nor can they "shift direction often". Orbits are exactly regular, by definition. Orbital parameter changes do happen but are rare. Even the largest spy satellites have only very limited ΔV capability. And there are no stealth…

Then tell me where these ones are: https://space.skyrocket.de/doc_sdat/usa-354.htm

Re: When a Telescope Is a National-Security Risk

#15

Post by nradov »

iudqnolq wrote: post #14
nradov wrote: post #5

Some of the language in this article is a bit odd, and appears to reflect a fundamental misunderstanding of satellites and orbital mechanics. The orbits of spy satellites are hardly "irregular", nor can they "shift direction often". Orbits are exactly regular, by definition. Orbital parameter changes do happen but are rare. Even the largest spy satellites have only very limited ΔV capability. And there are no stealth…

Then tell me where these ones are: https://space.skyrocket.de/doc_sdat/usa-354.htm

Those were already tracked by an amateur astronomer. What's your point?

https://sattrackcam.blogspot.com/2024/05/the-nrol-146-payloa...

Re: When a Telescope Is a National-Security Risk

#16

Post by iudqnolq »

nradov wrote: post #15
iudqnolq wrote: post #14

Earlier quoted context omitted.

Then tell me where these ones are: https://space.skyrocket.de/doc_sdat/usa-354.htm

Those were already tracked by an amateur astronomer. What's your point? https://sattrackcam.blogspot.com/2024/05/the-nrol-146-payloa...

> Over the coming days and weeks they will disperse along their orbital plane, and likely also raise their orbital altitude.

That's historic data

Re: When a Telescope Is a National-Security Risk

#17

Post by nradov »

iudqnolq wrote: post #16
nradov wrote: post #15

Earlier quoted context omitted.

Those were already tracked by an amateur astronomer. What's your point? https://sattrackcam.blogspot.com/2024/05/the-nrol-146-payloa...

> Over the coming days and weeks they will disperse along their orbital plane, and likely also raise their orbital altitude. That's historic data

Anyone who cares can find those satellites again using the same techniques. I guarantee the Chinese government knows their exact orbital parameters. There are no stealth satellites.

Re: When a Telescope Is a National-Security Risk

#18

Post by iudqnolq »

nradov wrote: post #17
iudqnolq wrote: post #16

Earlier quoted context omitted.

> Over the coming days and weeks they will disperse along their orbital plane, and likely also raise their orbital altitude. That's historic data

Anyone who cares can find those satellites again using the same techniques. I guarantee the Chinese government knows their exact orbital parameters. There are no stealth satellites.

But do the Houthis?

Re: When a Telescope Is a National-Security Risk

#19

Post by nradov »

iudqnolq wrote: post #18
nradov wrote: post #17

Earlier quoted context omitted.

Anyone who cares can find those satellites again using the same techniques. I guarantee the Chinese government knows their exact orbital parameters. There are no stealth satellites.

But do the Houthis?

Probably. The Iranians certainly have the technical capability to detect those satellites, at least well enough to calculate the orbital parameters. So it would be safe to assume that they pass that intelligence on to the various terrorist groups that they sponsor.

Re: When a Telescope Is a National-Security Risk

#20

Post by esbranson »

blockedepistem wrote: post #4

And people sound incredulous when they hear the likes of Shellenberger’s Public substack asserting that Uncle Sam has been sequestering UAP imagery away from scientific study. We’re going to be learning what a joke the past century of government transparency has been, and it’s not going to be a pleasant feeling.

The notion that this policy is to hide spy satellites from world or even regional powers is laughable.
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