Question

The brightest star in the night sky as seen from the Earth is;
A. Sun
B. Alpha centauri
C. Sirius
D. Pleiades

Answer 1

Hint: The brightest star which is visible from every corner of Earth is the star in the constellation Canis Major the Greater Dog. This star is often known as the Dog Star. Mostly this is visible from the Northern Hemisphere. That time it is seen in the southeast or the southwest on evenings from winter to almost mid-spring. February evenings are a better time to see it. It is easy to recognise this star as it ascends in the east before dawn on late summer mornings.

Complete answer:
Sirius is the brightest star in the sky. It is also called the “Dog Star. It is officially called Alpha Canis Majoris, because of its designation and position in the constellation Canis Major. Sirius is actually a binary star system which has a luminous main sequence star, Sirius A. Sirius appears the brightest due to its intrinsic luminosity and also its closeness to the Solar System. The Sirius system is considered as one of the neighbours of earth. It is found that the star is gradually moving in proximity to the Solar System, therefore the brightness will be increased over the next 60,000 years. This distance will start to increase after this time and it will become fainter, then also will remain as the brightest star in the night sky of earth for a long period of time.

So, the correct answer is “Option C”.

Note:
Among the Sirius stars, Sirius A is found to be double as massive as the Sun and is having a clear visual magnification also. It is considered to be 25 times more luminous than the Sun. Sirius is called a "Dog Star", because of the reflection it makes in its constellation. Sirius B is a white dwarf.