ISS, Tiangong, Satellites Over Puna

[TomK]

Well, I didn't even bother looking this evening given the clouds. Next decent evening event isn't until October 11th when we should see an extremely bright Iridium flare. Details nearer the time.

[HereOnThePrimalEdge]

TomK -
A new batch of 10 Iridium satellites was launched today to replace some of the older Iridium fleet which has been or will be de-orbited.
https://www.cbsnews.com/news/spacex-rock...atellites/
Do you know if the newer models have a similar design that will also flash?

All I could find on a quick search was that the antenna array is what reflects the sun:
As each Iridium satellite orbits the planet, it has a chance to reflect sunlight toward Earth from its triad of antennae.

“Facts fall from the poetic observer as ripe seeds.” -Henry Thoreau

[TomK]

HOTPE - I'm afraid Iridium flashes are on the endangered list and will soon become extinct. The new Iridium satellites are of a newer design and won't produce flares. The older satellites they replace will either be maneuvered into an orbit where they burn up in the atmosphere or if they don't have the fuel to do that, will be retired in orbit. As they won't be controlled after retirement, the satellites will likely start tumbling and the flares they produce will become unpredictable.

[TomK]

Apologies for the very late notice, but there is a very bright flare this evening in about 20 minutes. Time 19:22:13 and about 43 degrees above the horizon in the NNE. The satellite will be moving from the south to the North.

[TomK]

Sorry, false alarm, ignore my previous post, there is no flare.

PS. I had been logged out of the Heavens Above website and didn't realize it, so H-A was giving me predictions based on where I thought I was, which was a Verizon server in Honolulu. So, if you're in Honolulu, there's a very bright flare which you just missed!

The next one here is at 7 pm on Wednesday. I'll provide an update tomorrow.

[mermaid53]

LOL! We were out there looking for it and were a little bummed we couldn't find it amongst the bright stars... we saw a shooting star...we'll try again on the 11th.

[TomK]

Yeah, I was about to head outside but was puzzled as my ISS Detector app wasn't picking up the Iridium satellite, so went and checked H-A again and saw I wasn't logged in. I won't do that again!

I really am becoming fond of the app. If you turn on the "radar" it gives you a display which lets you point your phone in exactly the right direction in both altitude and azimuth for any object in its database.

[TomK]

OK, so this one is real! Tomorrow evening, Wednesday 11th October, there will be an Iridium flare at 19:00:12 which will occur in the NNE at an elevation of 47 degrees above the horizon. Most of Lower Puna should get a good view if the clouds hold off (the forecast is not promising right now). It will be super-bright at magnitude -8.0. Given that Iridium flares are going to become much rarer over the next year or two, it's time to get your fix now!

Sky map: https://goo.gl/EMb6Mp

Ground track of flare center: https://goo.gl/3yKxQb

[rocketman]

TomK, can you explain why the flares will become rarer?
Thanks

[TomK]

Rocketman - see my post above:

"HOTPE - I'm afraid Iridium flashes are on the endangered list and will soon become extinct. The new Iridium satellites are of a newer design and won't produce flares. The older satellites they replace will either be maneuvered into an orbit where they burn up in the atmosphere or if they don't have the fuel to do that, will be retired in orbit. As they won't be controlled after retirement, the satellites will likely start tumbling and the flares they produce will become unpredictable."

A couple of links:

http://www.skyatnightmagazine.com/news/e...ium-flares

http://news.nationalgeographic.com/2017/...e-science/