Why are such large units needed to measure distances in space?

Answer 1

Lightyears, the distance light travels in a year. Light travels roughly 186,000 miles a second.

Answer 2

The most common is the light year, which is the distance that a beam of light will travel in one year, and is approximately 10 trillion kilometres (or about 6 trillion miles).

Another unit of inter-stellar measurement is the parsec. One parsec is equal to about 3.26 light years (31 trillion kilometres, or 19 trillion miles).

Answer 3

Depends how 'long'.

Could be:

-- the AU

-- the light-year

-- the parsec

-- the megaparsec.

Each of them is 'often used', depending on

how long the distances actually are.

Answer 4

Within the solar system:

Astronomical Unit (AU):

The average distance of the earth from the sun.

Outside or extending beyond the solar system:

Light-year:

The distance light travels in one year through vacuum.

Parsec:

The distance from earth at which an object subtends a parallax of 1 arc-second

as seen by an observer on earth. Equivalent to 3.26 light years.

Answer 5

That is a Light Year, the distance a photon can travel in 1 year.

Also popular is the Parsec, a distance corresponding to a parallax of one second, which is equal to about 3.262 light-years.

Answer 6

Kilometers (but the large number of zeros does detract so) the most likely unit for distances WITHIN the solar system would be the Astronomical Unit (AU) the mean distance from the Earth to the Sun.

1 AU is about 150 000 000 kilometers, eight light minutes

Answer 7

For small distances, we use feet or meters; for longer distances on Earth, we use miles or kilometers. For interplanetary distances, astronomers generally use Astronomical Units, or "AU", where one AU is the distance between the Earth and the Sun; about 93 million miles or 150 million kilometers.

For interstellar distances, we typically use light-years or "parsecs". A light-year is the distance that light travels in one year, and a parsec is about 3.26 light years. For intergalactic distances, megaparsecs or millions of parsecs are sometimes used.

Answer 8

Within the solar system (that includes everything gravitationally bound to the sun, like planets,

moons, and comets), the most common measuring unit is the AU ... Astronomical Unit. It's the

average distance between the earth and the sun, which is about 93 million miles.

Outside the solar system, even that gigantic unit isn't long enough, and miles are totally useless. The

nearest star outside the solar system is 278,132 AU away from us, or about 25,866,280,000,000 miles.

You can see that a much larger unit is needed, so one was invented, called the "Light Year". It's simply

the distance that light travels in a year. Using that unit, the nearest star is 4.4 light-years away.
Light-year or parsec.

Answer 9

To answer this requires a little explaining and the answer will be in the explanation.

We measure distance in the solar system using the speed of light for the equation. The speed of light is 186,000 miles per second. When you multiply this by 60(number seconds in a minute), you have 11,160,000, the number of miles light will travel in one minute.

Now multiply 11,160,000 by 60 again(number of minutes in an hour)and you have 669,600,000, the number of miles light will travel in one hour.

Now multiply 669,600,000 by 24(number of hours in one day) and you have 16,070,400,000 number of miles light will travel in one day.

Now again, last time, multiply 16,070,400,000 by 365(number of days in a year) and you have 5,865,696,000,000 number of miles light will travel in one year.

That's a whole lot of multiplication. I hope I got the numbers right.

When we refer to a light year, that refers to that last set of numbers. That is the distance light will travel in one year.

So when we say a planet is 10 light years away, multiply that last number by 10 to get the distance that planet is from us.

The universe, solar system, galaxy, whatever term we use is infinite, meaning no boundaries, and forever expanding, has no end.

We will have to attain the speed of light and faster if we want explore further. Even at the speed of light, when we say a planet is 100 light years away, it will take 100 of our years to reach it. That would require a completely self supporting ship and the 3rd generation of the people on that ship will be the ones to reach that planet. Yes, there could be an original crew member, but very slim.

I have provided this answer based on layman's understanding. I

Answer 10

We can calculate the distance between two starts by using "parallax". The method parallax means triangulating the distance using geometry. Using basic geometry you can relate the two stars with the angles they make.

Think of it as a triangle. If you know the distance between two points in a triangle and the angle betwee those two points, you can calculate the distance for all three segments.