The reason why stars are so important is because they have helped humans navigate through Earth . When it was dark these stars would light up the sky giving people light . In addition stars are very important because they make life on Earth.

Astronomers classify stars according to their physical characteristics. Characteristics used to classify stars include color, temperature, size, composition, and brightness. Astronomers use spectrographs to determine the elements found in stars.

A star can be defined by five basic characteristics: brightness, color, surface temperature, size and mass.

Most of the stars in our galaxy, including the sun, are categorized as main sequence stars. They exist in a stable state of nuclear fusion, converting hydrogen to helium and radiating x-rays. This process emits an enormous amount of energy, keeping the star hot and shining brightly.

Sirius

Sirius is now rising in the southeast in the hours after midnight and can be found in the south at dawn. Notice that a line from Orion’s Belt points to Sirius. View larger. | Brightest star Sirius on left, with constellation Orion.

Earth’s atmosphere is constantly swirling around, and wind and air currents etc distort light travelling through it. This causes the light to slightly bend or shimmer and the light from distant stars twinkle. Sirius appears to twinkle or shimmer more than other stars for some very simple reasons.

You can always be sure you’ve found Sirius if a line through the three stars of Orion’s Belt point to it. Bottom line: Sirius is easy to find. It’s the sky’s brightest star on the sky’s dome. When you look at it, you’re looking backwards along our solar system’s path through the Milky Way galaxy.