Thread by @CosmicRami

I'm loving all the excitement around if Betelgeuse is about to go Supernova.

It really is a massive star and the explosion would be so friggen cool!

Here's the ALMA 'image' of Betelgeuse overlaid on our System - look how big it is!

Credit: Sci-News.com

The reason for all the chatter - Betelgeuse has dimmed in brightness over the last few months.

So much so, it is said to be noticeable with our eyes (we've had lots of smoke in the air, so I haven't had a good look myself)

Which I think is actually rather exciting in itself .... the ability to see the variability in the star's light using our eyes as instruments.

In fact, just a few weeks back, this was the EXACT topic of my essay (major project) for my History of Astronomy subject!

I looked at three ancient civilisations (Assyrian, Egyptian and Indigenous Australians) and if and how they used variable stars before the invention of the telescope.

Betelgeuse was one of them!

Here's a nice thread about the history of Betelgeuse dimming (HT @astro_jje)

https://twitter.com/EricMamajek/status/1208176941502590976

So did the ancient civilizations note the variability of stars with their eyes?

No and Yes ...

Well, the Assyrians didn't but the Egyptians and Indigenous Australian's did!

Firstly, the Assyrians were excellent astronomers and record keepers. They def. had noticed some big red stars and documented these in both the MUL.APIN and Enūma Anu Enlil tablets.

Betelgeuse was def. one of them!

They noted the heliacal rising of 35 stars; the ‘normal stars’ of the ecliptic and recorded specific stars such as Regulus, Polaris, Vega, Antares, Sirius – and yet, there is no indication that any naked-eye observations of variable stars have occurred from Mesopotamian cultures.

Likely because Mesopotamian cultures were predominately focused on lunar and planetary observations for the dedicated purposes of astrology during their epochs.

Like the Enūma Anu Enlil tablets contain approx. 6,500 omens associated with celestial objects and events!

The Egyptians on the other hand, def. were able to see (with their eyes) another variable star named Algol, and determine its change in brightness.

In fact, they recorded this variability into the Cairo Calendar – a 19th Dynasty Egyptian stellar almanac.

In 1783 Goodricke showed that Algol’s variability could be noted with the naked eye over a period of 2.867 days.

The Egyptians linked Algol's variability to the God Horus and ‘assigned luck’ into the Cairo Calendar – with a regularity of 2.85 days.

3,200 years ago!

And the third culture I looked into was Indigenous Australian's, who kept records on the variability of Betelgeuse, Antares and Aldebaran through traditional oral lore.

The red giants are described to be filled with 'fire magic' as they increase in brightness.

Here are some excellent papers from @DuaneHamacher @TrevorLeaman + more that you should def. check out about this:

aboriginalastronomy.com.au/research/paper…

These papers are fascinating and describe red giant variability from southern skies.

I learned so much writing this essay!

Image credits from thread:

1. Assyrian Tablet: British Museum

2. Cairo Calendar: Jetsu, L. & Porceddu, S.

3. Indigenous Australian Orion: Journal of Astronomical History and Heritage

There's def. more to naked eye observations of variable stars throughout time - so def. go explore more if you get a chance.

I've only covered this really briefly, but it is really fascinating to read about ancient cultures and how they used the stars!

Also, if you say its name three times out loud, it might* trigger the supernova.

* This is based** on science

** This is not at all based on science

Credit: The Verge