Stars and their effect on planets

[Gerard]

What follows is a good case.

 

The granitic outcrop known as "Peña Sirio" is located in La Pedriza nature reserve (Spain). The name to this cliff was given in the early XX century by some locals who noticed that the star Sirius was coming out behind this cliff during the night hours.

 

Sirius is the brightest star in the night sky. Its name is derived from the Greek word Σείριος (Latin script: Seirios), meaning lit. 'glowing' or 'scorching.'

 

Incidentally this area is scorching hot in the summer months. 

 

Sirius is colloquially known as the "Dog Star", reflecting its prominence in its constellation, Canis Major (the Greater Dog). The heliacal rising of Sirius marked the flooding of the Nilein Ancient Egypt and the "dog days" of summer for the ancient Greeks, while to the Polynesians, mostly in the Southern Hemisphere, the star marked winter and was an important reference for their navigationaround the Pacific Ocean.

 

Source: https://en.m.wikipedia.org/wiki/Sirius

Doesn't Peña Sirio have an uncanny resemblance to a dog?

 

Edited November 14 by Gerard

[Thrice Daily]

I thought readers may find this interesting,,, 

 

The North Star, also known as the Pole Star, has not always been Polaris, and it won't remain so indefinitely. This change is due to a natural astronomical phenomenon called axial precession. Here's a detailed breakdown of the process and its implications:

1. Axial Precession: The Cause

• Earth's Tilt: The Earth is tilted at an angle of about 23.5 degrees relative to its orbital plane.
• Wobbling Axis: Over time, the Earth's rotational axis traces a circular motion (similar to the wobble of a spinning top). This is called precession.
• Cycle Length: This motion takes approximately 26,000 years to complete one cycle.
• As a result, the "celestial north pole" (the point in the sky directly above Earth's north rotational axis) gradually shifts position over millennia.

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2. Changing North Stars

• Polaris: Currently, Polaris is close to the celestial north pole and serves as our North Star. It's located in the constellation Ursa Minor.
• Past North Stars:
  • Around 3,000 BCE, the North Star was Thuban, in the constellation Draco.
  • Before that, in about 12,000 BCE, the North Star was Vega, in the constellation Lyra.
• Future North Stars:
  • In about 14,000 years, Vega will once again be the North Star as the celestial north pole moves back toward it.

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3. Why is Polaris Special Now?

• Close Alignment: Polaris is currently almost perfectly aligned with the celestial north pole, making it an excellent reference point for navigation in the Northern Hemisphere.
• Brightness: Polaris is also relatively bright, making it easy to spot in the night sky.

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4. What About the Southern Hemisphere?

• The Southern Hemisphere lacks a bright star close to its celestial south pole. The closest is Sigma Octantis (Polaris Australis), but it is much dimmer than Polaris.

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5. Astronomical and Historical Significance

• Navigation: Historically, the North Star has been crucial for navigation, especially before modern tools.
• Cultural Impact: Changes in the North Star could influence cultural and mythological interpretations of the sky in ancient civilizations.

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6. Observing the Transition

While the transition of the North Star happens very slowly over thousands of years, modern astronomy has precisely tracked this movement. Today, we understand the changing pole stars as part of Earth's ongoing celestial dynamics.