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Sirius, the brightest star in the night sky.
Still doing quizzes on Zoom? If you are – and you have to make up questions for others – here is one that almost everyone is wrong:
What is the brightest star in the night sky?
The most popular answer is always the same: the North Star.
No, the brightest star in the night sky is do not the North star.
It’s Sirius, a bright blue star that this weekend becomes briefly visible in the pre-dawn sky to those of us in the northern hemisphere.
Is the North Star the brightest star in the night sky?
No, it’s actually the 48th brightest. Only visible from the Northern Hemisphere, the North Star is directly above the North Pole.
It is also called Polaris. Since the points of the Earth’s axis seem to point directly at it, Polaris never seems to move, only to rotate.
It always sits above north, and its height above the horizon gives your latitude – your distance from the equator (at the equator you can’t see Polaris, and at the North Pole it is directly above your head).
In any star track image taken from the Polaris Northern Hemisphere, the North Star, will be the at … [+]
Sirius is the brightest star in the night sky
Sirius, in the constellation Canis Major, shines at a magnitude of -1.46, so it has long been a well-known star in many ancient cultures. It is the fifth closest star system to ours. It is best described as Sirius A because a second star, Sirius B, is also part of what is a binary system.
Why this weekend’s heliacalising ‘from Sirius is significant
This weekend is the heliacal rise– the first annual appearance in the pre-dawn sky – of Sirius. On Saturday it became briefly visible above the eastern horizon just before sunrise after a six-week period of being lost in reflections from the sun.
To mark the harvests, the heliacal uprising of Sirius was important to several cultures, including the ancient Egyptians.
Why Sirius is called the “ Dog Star ”
Besides Alpha Canis Majoris, Sirius is also referred to as “Dog Star”. Its name “Sirius” comes from the Greek word for “bright” or “burning”, while “Dog Star” comes from the fact that it is the brightest star (by far) in the constellation Canis Major, the great hunting dog.
Have you ever heard the expression “dog days of summer”? This concerns the hottest days of summer in the northern hemisphere – right now. This is because the presence of Sirius in the daytime sky near the Sun was believed to intensify the heat of the day. That’s not how it works at all, but the name stuck.
The constellation of Canis Major, the great hunting dog of Orion. (Photo by: VW Pics / Universal Pictures … [+]
The 5 brightest stars in the night sky
The North Star does not come close to the five brightest stars in the night sky, namely:
- Sirius (visible from both hemispheres).
- Canopus (visible only from near the equator and the southern hemisphere – although it can be seen rising from the southern states of the United States in late winter).
- Alpha Centauri (widely visible from the southern hemisphere, although it is possible to see it around 25 ° N in winter in the northern hemisphere).
- Arcturus (easily visible from the northern hemisphere all spring and summer).
- Vega (easily visible from the northern hemisphere all summer and fall).
I wish you clear skies and wide eyes.
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