Question

Fill in the blank:
_________is the biggest star of the night sky.
A) Alpha Persei
B) Sirius
C) Pole Star
D) Vega

Answer 1

Hint: The mass of the star is much important to know the luminosity or brightness of the star. Among these stars, the massive star would have more brightness and the position of the star is a factor of measuring its luminosity when observing from the earth.

Complete step by step answer:
The studies of NASA points that Sirius has mass double that of the Sun. While compared to the Sun, Sirius would have more brightness. The name Sirius means “glowing” in the Greek language. Sirius is also known as Sirius A. This star is $8.6$ light years away from the Earth which is almost close to Earth.
The star is visible through the naked eye. It is because of its brightness compared to other stars. Sirius belongs to the Constellation Canis Major the Greater Dog. When Sirius appears in low sky the flashing colors in white starlight are observed. This is because Sirius is brighter than other stars. When Sirius appears in the High sky the sparkling is less and appears less colorful. Near the horizon, the Earth’s atmosphere is thicker. Thus it seems like a prism. The starlight splits into colors while passing through the Earth’s atmosphere.
The answer is option B.

Note:
Sirius is included in the category of stars having “Proper motion”. Their angular momentum can be predicted when they move across the sky. This is difficult for more distant stars. Sirius is much closer to earth and more visible and luminosity is high.