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To: ETL
Gorgeous astro photo. I thought "satellite flare" was the author's mistaken confusion of a lens flare. Turns out the glint of sun reflection from a satellite is called "satellite flare." So another day, another gem of knowledge from FR!

When our kids were little, we used to lie on our backs at night in the mountains counting satellites. The kids' visual acuity was great and they'd always spot them before me. We also had a fly-over of the ISS in FairPlay, CO last year. That was really spectacular.

Here's an animation of satellite flare from Wiki...


4 posted on 09/23/2018 9:40:54 AM PDT by ProtectOurFreedom
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To: ProtectOurFreedom

Probably flares from the Iridium sats are the most common.


8 posted on 09/23/2018 9:50:15 AM PDT by Calvin Locke
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To: ProtectOurFreedom; All
Turns out the glint of sun reflection from a satellite is called “satellite flare.”

Check out this site (linked below) for the scheduling of “Iridium Flares” in your area. You’d need to enter in your location, the more precise the better.

Some of these flares are incredibly bright, up to negative 8! However, most I think are around -2 or -3.

From their site...

“The Iridium satellites are relatively small telecommunications satellites in a low Earth orbit. They are part of a world-wide system for mobile communications operated by the Iridium LLC Corporation. When complete, there will be a total of 66 satellites in 6 orbit planes, at an altitude of around 780km.

As can be seen from the diagram opposite, each satellite has three main mission antennas (MMAs), which are flat, highly reflective surfaces, that can reflect the Sun’s rays to an observer on the ground when the geometry is correct. The satellite’s attitude is controlled so that the long axis remains vertical, with one MMA always pointing forwards.

Given this knowledge of the attitude, together with the orbital position of the satellite and the Sun and observer’s location, it is possible to calculate the angle between the direction to the observer from the satellite and the line of a perfect reflection of the Sun. This is the so-called “mirror angle” and determines the magnitude of the flare.

An Iridium Flare The photo on the right of two Iridium flares was taken by Porter Kier on January 11th, 1999. It shows Iridiums 20A (Mag. -2) and 22 (Mag. -7) above the Chesapeake Bay, Virginia area. For more information on the photo, and a full size version, just click on the image.”

Scroll down their home page to Satellites—> Iridium Flares for the scheduling. Again, enter your location first!

https://www.heavens-above.com/

9 posted on 09/23/2018 9:50:51 AM PDT by ETL (Obama-Hillary, REAL Russia collusion! Uranium-One Deal, Missile Defense, Iran Deal, Nukes: Click ETL)
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To: ProtectOurFreedom

We also had a fly-over of the ISS in FairPlay, CO last year. That was really spectacular.


Watched a flyover of ISS with Shuttle (remember those, when we could get to space on our own) docked to it. With binoculars could make out each space craft.


12 posted on 09/23/2018 10:14:41 AM PDT by hanamizu
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To: ProtectOurFreedom
Great graphic by the way. Didn't really look at it until now.


22 posted on 09/23/2018 10:44:17 AM PDT by ETL (Obama-Hillary, REAL Russia collusion! Uranium-One Deal, Missile Defense, Iran Deal, Nukes: Click ETL)
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