1
: a unit of length in astronomy equal to the distance that light travels in one year in a vacuum or about 5.88 trillion miles (9.46 trillion kilometers)
2
: an extremely large measure of comparison (as of distance, time, or quality)
seems like light-years ago
has light-years more talent
two minutes and yet light-years away from the crowded village—
Suzanne Patterson
Suzanne Patterson
Examples of light-year in a Sentence
my sister and I are close in age, but personality-wise, there are light-years between us
Recent Examples on the Web
There are other ways of seeing what things were like back then: Astronomers can point cameras directly at galaxies that are 5 billion light-years distant and capture light that left them 5 billion years ago.
—Ross Andersen, The Atlantic, 5 Nov. 2024
Appearing like a pair of red eyes in the darkness of space, the two galaxies are located millions of light-years away from Earth.
—Marco Rubio, Newsweek, 2 Nov. 2024
Vega: ‘Uniquely Smooth’ Disk Just 25 light-years from the solar system, Vega is 455 million years old, a tenth of the age of our sun, but 40 times brighter.
—Jamie Carter, Forbes, 1 Nov. 2024
Related article Astronomers’ discovery of distant Milky Way-like galaxy challenges our theories of how cosmos evolved
Euclid is designed to observe billions of galaxies that stretch 10 billion light-years away to reveal how matter may have been stretched and pulled apart by dark energy over time.
—Ashley Strickland, CNN, 23 Oct. 2024
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Ross Andersen, The Atlantic, 5 Nov. 2024
Appearing like a pair of red eyes in the darkness of space, the two galaxies are located millions of light-years away from Earth.
—Marco Rubio, Newsweek, 2 Nov. 2024
Vega: ‘Uniquely Smooth’ Disk Just 25 light-years from the solar system, Vega is 455 million years old, a tenth of the age of our sun, but 40 times brighter.
—Jamie Carter, Forbes, 1 Nov. 2024
Related article Astronomers’ discovery of distant Milky Way-like galaxy challenges our theories of how cosmos evolved
Euclid is designed to observe billions of galaxies that stretch 10 billion light-years away to reveal how matter may have been stretched and pulled apart by dark energy over time.
—Ashley Strickland, CNN, 23 Oct. 2024
See all Example Sentences for light-year
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Cite this Entry
“Light-year.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light-year. Accessed 20 Nov. 2024.
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