The solar system is a part of which galaxy?
- A.Andromeda
- B.The Milky Way
- C.The Large Magellanic Cloud
- D.Triangulum
Correct answer
Explanation
The correct answer is B, the Milky Way, called Akash Ganga in Indian tradition. It is a spiral galaxy of a few hundred billion stars, and the solar system lies in one of its spiral arms, far from the centre, which is why we see the galaxy edge on as a milky band across the night sky. Option A, Andromeda, is the nearest large galaxy to ours, also a spiral, and the two are expected to approach each other over billions of years; students often pick it because the name is familiar. Option C, the Large Magellanic Cloud, is an irregular satellite galaxy of the Milky Way visible from the southern hemisphere. Option D, Triangulum, is another spiral galaxy of the local group. The classification worth remembering is spiral, elliptical and irregular, and the term galaxy means a gravitationally bound system of stars, gas, dust and dark matter.
Read the full article: Space Science: Stars, Galaxies and Satellites Notes
Practice Questions
View allThe source of the Sun's energy is
- A.Fusion of heavy nuclei
- B.Fusion of lighter nuclei
- C.Fission of light nuclei
- D.Fission of heavy nuclei
Show answer
In the core of the Sun, at a temperature of about fifteen million kelvin, four hydrogen nuclei combine through the proton-proton chain to form one helium nucleus.
Read the full explanation →What is the reason behind the twinkling of stars?
- A.Scattering of light by dust particles
- B.Internal reflection of light by clouds
- C.Atmospheric refraction of star light
- D.Dispersion of light by water droplets
Show answer
A star is so far away that it is a point source of light.
Read the full explanation →Once a satellite has been launched into orbit, the only force governing its motion is the force of ______.
- A.gravity
- B.elasticity
- C.friction
- D.fuel driven
Show answer
A satellite is given the required height and speed by its launch vehicle, and after that no engine is needed: the gravitational pull of the earth alone acts on it and provides the centripetal force that keeps it in a curved path, so the satellite keeps falling towards the earth…
Read the full explanation →A light year is a unit of
- A.Time
- B.Distance
- C.Brightness
- D.Mass
Show answer
A light year is the distance travelled by light in vacuum in one year, which is about 9.46 times ten to the power twelve kilometres, or roughly nine and a half trillion kilometres.
Read the full explanation →Which is the nearest star to the earth after the Sun?
- A.Sirius
- B.Proxima Centauri
- C.Polaris
- D.Betelgeuse
Show answer
Being a red dwarf it cannot be seen with the naked eye, although it is the closest star to us after the Sun.
Read the full explanation →