Question

The unit of measurement of the distance of stars from the sun is called
1. Light year
2. Fathoms
3. Nautical miles
4. Nano meters

Answer 1

Correct Answer - Option 1 : Light year

The correct answer is Light year.

• A light-year is a unit of distance. It is the distance that light can travel in one year.
• Light moves at a velocity of about 300,000 kilometers (km) per second.
• So, one light-year is equal to 9.5 × 10¹² kilometers.
• This light-year distance is known as the Astronomical Unit (AU).
• Distances to other parts of the Milky Way Galaxy or even further, astronomers use units of the light-year or the parsec.

• Fathom is a unit of length in the imperial and the U.S. customary systems equal to 6 feet (1.8288 m), used especially for measuring the depth of water.
• A nautical mile measures distance and a knot measures speed.
  • A nautical mile is based on the circumference of the earth and is equal to one minute of latitude. It is slightly more than a statute (land measured) mile (1 nautical mile = 1.1508 statute miles).
• The prefix "nano" means one-billionth or 10^-9, therefore one nanometer is one-billionth of a meter.
  • It is used for comparison, a single sheet of paper is approximately 100,000 nanometers thick and a strand of DNA is 2.5 nm across.

• 1 light-year in miles = 5.88 × 1012 miles.
• 1 light-year in Astronomical unit = 63241 au.
• The distance between the sun and earth is 15.54795 × 10-6 light-years.
• Light-Year is also helped to determine the age of the celestial body.