Correct so far...

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That's surprising. So, Arneb, what is IS? [This is a US joke.]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

yes what is the ..is?

Like the HB, the IS is part of the HR diagram...

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IS might be Instability strip, the answer RR, for RR Lyrae?

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

We have winner.

RR Lyrae variables occupy the part of the HR diagram where the horizontal branch overlaps the instability strip. In the General Catalog of Variable Stars the code for RR Lyrids is RR.

I use this "equation" as a mnemonic to help me remember what RR Lyrids are.

You're up slang.

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Oh man, now I have to come up with something as clever as this one or as most of the other questions I've looked at, and be able to answer all the deep questions that the experts ask? That's what I get for having to read up on what exactly the HR diagram contained and having the answer jump in my face

Alright, I'll give it a go..

This examines the past, but is where one should remember the past.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

It seems everyone is stumped. Is it one of those underground facilities that are trying to detect some elusive particle or other?

Hint?

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You are correct in thinking of an instrument, but it is not underground. The 2nd "past" is tied to its location, but it's a little obscure for most, I think. Think some 60 odd years ago.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

Atomic bomb? Neutrino detector?

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"I will do my best to understand and explain the universe from big to small without invoking miracles, unrepeatable events, or divine intervention. In place of those things I will use observations, mathematics, and science."


-Cross
My travel blog

Some of my Astrophotography


Those that lack education have a hard time understanding its value. - Cross

Nope, and nope. If I remember correctly it was once the largest of its kind on the world.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

It is composed of several identical components.

__________________
"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

A German underground rocket production plant?

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What goes around, comes around, eventually.

Meade DS-10 (10" newt)
10x50, 10x70 binos

No. There's a much more direct astronomy connection here. It was built in the sixties and played a role in discovering black holes, if wiki is not mistaken.

edit: is there protocol on when to give the answer, if nobody guesses?

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

I am thinking of a radio telescope. I have some patriotic pride in this instrument.

__________________
"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

The VLA down the road a piece from me?

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What goes around, comes around, eventually.

Meade DS-10 (10" newt)
10x50, 10x70 binos

No. It's located in my country.

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

Westerbork has an array of radio telescopes and was the site of a World War II concentration camp.

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Curt Renz - "Centaur"
For monthly astronomical calendar visit:
www.CurtRenz.com/astronomical.html

Centaur wins!

The Westerbork Synthesis Radio Telescope was built in the sixties. It is operated by ASTRON and currently involved in projects like the LOw Frequency ARray.

The camp in Westerbork was actually more of a transit camp for transporting people east. The irony of it is that originally it was built as a refugee camp for jewish people fleeing from Germany. After the war started it was used for more nefarious reasons.

*passes the baton to Centaur*

good luck, Curt

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"Ignorance more frequently begets confidence than does knowledge" -- Charles Darwin

"Ignorance convinces" -- slang's dad

The history is sad, Slang, but I’m glad the area is now being put to good use.

Next question: When was the last time that the Moon occulted Pollux (the first magnitude star in Gemini) for any location on Earth?

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Curt Renz - "Centaur"
For monthly astronomical calendar visit:
www.CurtRenz.com/astronomical.html

I'll guess never because the Moon never "rides" that high to reach it? I may be wrong, after all, I'm not a lunatic Mr Q

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What goes around, comes around, eventually.

Meade DS-10 (10" newt)
10x50, 10x70 binos