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The end of Iridium flares?

heavens-above.com

51–60 of 68 posts

Re: The end of Iridium flares?

#51
post #14

Earlier quoted context omitted.

trying to envision said parties

Rooftop parties in the city, drinking beer from bottles, strings of vintage lightbulbs, people wearing plaid, taking out your phone to say “Hey look at this!” and pointing out a spot in the sky where an iridium flare streaks across while everyone gasps “Wwwooww!!” High fives

Sounds like my experience in Melbourne. It was the plaid that really hit the spot.

Re: The end of Iridium flares?

#52
post #37

Does the tracker actually model the directed reflections or just the relative angle of the viewer, the satellite and the sun and let chance take care of the rest?

IIRC it is a fairly precise model. They know which antennas, and the directed reflection. The width ground track is not all that wide, but if you're right in the middle of it they're very bright. Years ago I drove to be in the center of the path and could easily see the flare in broad daylight.

Re: The end of Iridium flares?

#53
post #44

Earlier quoted context omitted.

Really cool. My dad used to make me go around to teachers before a big meteor shower with documentation as to why this year's shower was "gonna be the big one" and me being out of school the next day should be an excused abcense. That translates to at least ten summers of one night a year under the stars during a shower. Your story reminded me of a time when what must have been a school bus of space dust burned acros…

I wonder if it was the 1998 Leonids. I got about 25 people from my college dorm to drive to the beach that night. It was the night of the fireballs. Another great memory.

That's a beautiful memory for me too! A lot of us gathered in the college ground and spent 1-2 hours watching the beautiful spectacle. I started to count, and then after sometime just gave up the counting. Never have got another chance after 1998 to see so many in one night.

Re: The end of Iridium flares?

#54

Earlier quoted context omitted.

You should seek out a flare if you can, it's much much brighter than seeing a satellite or the ISS, as impressive as those are.

Hmm, so an Iridium satellite is much brighter than a satellite or the ISS (a satellite). Got it!

An Iridium flare can be much brighter than any other satellite including the ISS.

The Iridium satellites are not very bright most of the time - you would be lucky to see one with the naked eye. But when they flare, they can be the brightest thing in the night sky for a few seconds.

Re: The end of Iridium flares?

#55

Is there a heat dissipation reason why satellites are painted white instead of black? And if so, why are they white instead of a completely reflective surface?

White and black are really the same colour, or lack of colour. The moon is actually like tyre rubber. But a tyre being lit by the sun at night is still brighter than anything else.

Re: The end of Iridium flares?

#56
post #22

An interesting fact is why the name Iridium? When they were in the planning stages for this set of satellites, they estimated that they would need 77 of them to completely cover the Earth (including the poles), evoking an image of 77 electrons circling the nucleus of an atom. The atomic number for the element Iridium is 77. The number of satellites needed was paired down to 66, so the satellites should actually be na…

Cambridge Consultants designs a lot of their subscriber equipment - modems, handsets etc. Their internal project name for the Iridium work is Dysprosium for exactly this reason.

Re: The end of Iridium flares?

#57

Is there a heat dissipation reason why satellites are painted white instead of black? And if so, why are they white instead of a completely reflective surface?

Satellites are not painted white. Satellite bodies are are typically covered with reflective thermal blankets made of materials like Mylar or Kapton [1][2][3]. However, what makes satellites reflect enough sunlight to be visible in the sky is not the blankets but solar panels or antennas.

[1] https://en.wikipedia.org/wiki/Space_blanket

[2] https://en.wikipedia.org/wiki/BoPET

[3] https://en.wikipedia.org/wiki/Kapton

Re: The end of Iridium flares?

#58
post #22

An interesting fact is why the name Iridium? When they were in the planning stages for this set of satellites, they estimated that they would need 77 of them to completely cover the Earth (including the poles), evoking an image of 77 electrons circling the nucleus of an atom. The atomic number for the element Iridium is 77. The number of satellites needed was paired down to 66, so the satellites should actually be na…

pared down

As in the thing you do with a paring knife.

Re: The end of Iridium flares?

#59
post #22

An interesting fact is why the name Iridium? When they were in the planning stages for this set of satellites, they estimated that they would need 77 of them to completely cover the Earth (including the poles), evoking an image of 77 electrons circling the nucleus of an atom. The atomic number for the element Iridium is 77. The number of satellites needed was paired down to 66, so the satellites should actually be na…

Yes, original Motorola design called for 77 which drove the name, which stuck.
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