Midnight Stars
updated: Dec 21, 2012, 6:45 PM

By Chuck McPartlin

I decided to get the jump on Doomsday by looking with some telescope time this morning. Here's a shot from just after midnight of a star cluster called M67, or NGC 2682. It's about 2700 light years away, about 10 light years across, and contains an estimated 500 stars. The light we're seeing left those stars around 700 BCE, just about when the Maya started piling up seriously big stone monuments.

M67 is classed as an open cluster. Open clusters are gravitationally bound groups of young stars, like the bright Pleiades cluster visible next to Jupiter in the winter sky this year. Young for a star usually means a couple of million years, and clusters eventually evaporate as their member stars interact gravitationally.

Judging by the spectral characteristics of the stars in M67, it is about 3.2 to 4 billion years old, a bit younger than our Sun. Thus, many of its constituent stars have depleted their nuclear fuel and evolved off the main sequence into red giant stars (sorry, it's a black and white camera). Since many of its stars are similar in mass and chemical composition to our Sun, astronomers look at the range of stars in M67 to see how the life of our star might progress.

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Comments in order of when they were received | (reverse order)

COMMENT 356596P	2012-12-22 06:34 AM
Beautiful. Thank you for the photo and the lesson. :-)
COMMENT 356610	2012-12-22 07:33 AM
Is that an image of Jesus in that photo? Nice write up, by the way.
COMMENT 356623	2012-12-22 07:53 AM
Since the op used the term bce I don't think he knows who this Jesus guy you are referencing.
COMMENT 356633	2012-12-22 08:04 AM
Wow. Amazing. I think you'd make a great regular poster!
RDH	2012-12-22 08:25 AM
Thank you very much for the fascinating bit of stellar history. Had our world indeed collapsed or exploded or otherwise disintegrated last Friday, observers on M67 would not know about it until 4712.
COMMENT 356656	2012-12-22 08:52 AM
Cue music: "It's the end of the world as we know it... " o/~
COMMENT 356680P	2012-12-22 09:53 AM
Lots of people use bce; it's called being polite. It indicates you're a person interested in communicating with others. Are you aware how much astronomical knowledge we got from the Arabs, just for instance? Astronomy is an old science, going way back bce.
ABERMANT	2012-12-22 10:22 AM
633 is right - what a great Edhat column this would be. What I like most is how you speak Astronomy in human terms - thanks and I hope you'll post more lessons in the future.

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