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Electro-magnetic waves travel at approx 300 000 km per second in free space,
so we may determine the distance to an object (say a reflector on the moon),
by measuring the time from when we sent the pulse,
to the time when the pulse is returned.
AND divide that by two, for the EM wave travelled the distance twice.
Optical-telescopy techniques such as parallax, using the Earth's own orbit to produce a base-line nearly 298 000 000 km across, are used to calculate distances. That's insignificant in space terms but sufficient to allow parallax calculations of distance. The unit is called the Parsec (from PARallax in SEConds of arc). Distances are also in Light Years: the distance travelled by light in vacuo in 1 year. Kilometres would be used only for close-in work (mainly within the Solar System and for star and planet diameters). Star diameters are also referred to as "N times-the-diameter-of-the-Sun" or "N times the mass of the Sun", depending on purpose. Numbers counting km would be expressed exponentially, so the Earths' orbit diameter and a light-year are approx 2.98 X 108 and 6.814 x 1012, km respectively.
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Does light year denote distance on earth?
No. A light year measures such large distances that it would be highly impractical to measure anything on Earth. The light year is used to measure distance in space beyond the solar system.
What system is used to measure distance in Brazil?
The metric system is used to measure distance in Brazil. Distances are typically measured in kilometers (km) and meters (m).
What is the type of star used by Hubble to measure the distance to other galaxies?
what is the type of star used by the Hubble to measure the distance to other galaxies.
What is the SI unit used to measure length or distance?
The SI unit used to measure length or distance is the meter (m).
How long is 28 by 78 cm in inches?
There is no equivalence.An inch is a measure of length or distance in 1-dimensional space while 28 by 78 cm is a measure of area in 2-dimensional space. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid.There is no equivalence.An inch is a measure of length or distance in 1-dimensional space while 28 by 78 cm is a measure of area in 2-dimensional space. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid.There is no equivalence.An inch is a measure of length or distance in 1-dimensional space while 28 by 78 cm is a measure of area in 2-dimensional space. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid.There is no equivalence.An inch is a measure of length or distance in 1-dimensional space while 28 by 78 cm is a measure of area in 2-dimensional space. The two measure different things and, according to basic principles of dimensional analysis, conversion from one to the other is not valid.
What is the measurement used to measure distance in space?
Distance in space is measured in 'light years' or in 'scientific notation'
What two units are used to measure distance in space?
Lightyears and miles
What unit of distance used to measure items in space?
Light years: the distance that light travels in a year.
How do you measure the distance or space of the distance clip?
how do you measure the distance or space of the distance clip. this clip use in textile spinning mills. it is errected on the craddle.
Used to measure distance in space equal to the distance light travels in one year?
That is called a light-year, and it is equal to a distance of about 9.5 trillion kilometers.
In what field of science is a parsec used?
Astronomy. It is a measure of distance in space and is equal to 19.17 trillion miles.
What part of speech is lightyear?
"Lightyear" is a noun. It is a unit of distance used to measure interstellar space.
Does light year denote distance on earth?
No. A light year measures such large distances that it would be highly impractical to measure anything on Earth. The light year is used to measure distance in space beyond the solar system.
What is cm used to measure?
Centimetres or cm are used to measure distance
What does au stand for in terms of distance?
Astronomical Unit - A unit of measure used in space. It is the mean distance from the Earth to the Sun. 93 million miles or about 150 million kilometers.
When would you use a light year?
When I want to measure a distance in space.
What system is used to measure distance in Brazil?
The metric system is used to measure distance in Brazil. Distances are typically measured in kilometers (km) and meters (m).
