Twenty million years ago a then nonexistent earth-bound human civilization could recognize none of the prominent stars of the constellation Scorpius (The Scorpion) as these, compared to our 4.6 billion year old star, lit up less than 12 million years ago. The brightest star, Alpha Scorpii AKA Antares, is a red giant destined to burst into a supernova bright as the full moon within two million years. Will the human race be around to witness it?
Such as it is, The Scorpion was traced out by the Babylonian astronomers around 8 BCE following even more ancient Sumerian traditions naming Alpha Scorpii “The Heart of the Scorpion.”
I first became aware of Antares March 2009 during a stay on Cocoa Beach. Setting the room clock to a 5 am alarm to view the sunrise. As I sat listening to the surf, Antares glowed dark red in the south. It is the reddish tint star in the following illustration.
Here is a photograph of Antares, the reddish dot in center, along with the 6 of the 18 Scorpius bright stars. For this shot a Canon EOS 5D Mark IV dlsr had mounted a Canon lens EF 70-300 f4-5.6L IS USM set to 70 mm focal length, 1600 ISO. Exposure was “bulb,” meaning when the shutter button is pressed and held the shutter remains open: for this exposure this was for approximately 10 seconds. The equipment was held steady on a Manfrotto BeFree Carbon Fiber tripod. As the Earth continued to turn, the resulting star images are smeared a bit.
Bracketing Antares, the Scorpion Heart are “The Arteries” Theta and Tau. About those Greek letters, these designate relative brightness of each star respective of the others in the constellation. “Alpha” the first letter of the Greek alphabet is the brightest. Here are the other letters listed, with the alphabetic order in brackets Beta(2), Delta(4), Pi(16), Sigma(18), Tau(19). Ancient Greek built on the traditions of the Mesopotamians (Babylonian and Sumerian) and were in turn used for modern stellar nomenclature, including the tracings of sky images, the constellations.
The position of a relatively minor star, Tau, near Antares elevates it to the important function of an artery. The stars themselves run against their brightness hierarchy placement: The star Delta Scorpii, after having been a stable 2.3 magnitude star, flared in July 2000 to 1.9 in a matter of weeks. It has since become a variable star fluctuating between 2.0 and 1.6. This means that at its brightest it is the second brightest star in Scorpius.
