It only takes light about eight minutes to go from the Sun to Earth.
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The fastest things ever made by humans are spacecraft, and the fastest spacecraft reached 330,000 mph – only 0.05% the speed of light. But there are ways to go faster.
A fly regurgitating digestive juices.
Carlos Ruiz
A fly does some of its digesting outside its body before it even eats any food.
Three upright walkers, including Lucy (center) and two specimens of Australopithecus sediba , a human ancestor from South Africa dating back nearly 2 million years.
Image compiled by Peter Schmid and courtesy of Lee R. Berger/Wikimedia Commons
Walking has taken a very long time to develop, with evidence of bipedalism among early humans in Africa roughly 4.4 million years ago.
On average, two students in every U.S. classroom have ADHD.
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Even when the condition lasts a lifetime, there are behavioral treatments and prescription drugs that make it easier for people with attention-deficit hyperactivity disorder to thrive.
Your teeth will be better off if you refrain from chomping on ice cubes.
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A dentist explains why this is a habit worth breaking – no matter the cause or the strength of your cravings to keep doing it.
The collective memory of school desegregation is of anger and division, like in this photo of 15-year-old Elizabeth Eckford walking away from a crowd outside a high school in Little Rock, Ark.
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Americans’ collective memory of school desegregation involves crowds of screaming white protesters. But less well known are the whites who stood by quietly, and those who approved of the changes.
The American Academy of Pediatrics says teens should never consume energy drinks.
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Energy drinks and coffee both contain lots of caffeine. That’s a problem for teens, especially those who take prescription stimulants.
Astronomers have found a way to estimate the number of stars in the universe.
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Scientists have a good estimate on the staggering number of stars in the universe.
That pins-and-needles feeling can come from sitting in the same position for a while.
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An exercise physiologist explains how it’s a problem of communication between your brain and your body.
The Earth is round.
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Gravity, mass and centrifugal force all contribute to the final shape of a planet.
COVID-19 vaccines have been proved safe and effective. But it’s understandable to have questions.
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An infectious disease doctor explains the science behind COVID-19 vaccines at a level that children – and adults – of all ages can understand.
Planting 8 billion trees a year would replace about half of the 15 billion cut down annually.
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Planting a massive number of trees can help slow climate change, but it is only part of the solution.
Tyrannosaurus rex was a relentless predator who lived during the Cretaceous Period more than 65 million years ago.
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Ever since moviegoers saw the first ‘Jurassic Park,’ millions have wondered if scientists could make a dinosaur in the lab.
Beer, wine and hard liquor are causing nearly 100,000 U.S. deaths a year.
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Consuming alcohol makes accidents more likely and it can harm your heart, your liver and even change your brain. But making the sale of beer, wine and hard liquor illegal flopped.
The planet and the way we live on it are constantly changing.
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The Earth is constantly changing in natural ways, but most of those changes are very slow. Humans are speeding up other changes with global warming.
Gravity feels like it’s pulling everything toward Earth, but why?
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Gravity is something every person on Earth intuitively understands: It is what keeps you on the ground. But how come gravity pulls down, rather than pushes up? Einstein came up with the answer.
Artist illustration of an exoplanet.
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Billions of galaxies are in the universe, with billions of stars in every galaxy. Could billions of planets be out there too?
Whether big or small, if you see something that people need, you can start a company.
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There are five basic things to address while starting your own company: Need, idea, product, setup and market.
Sneezing with your eyes closed is a reflex you can consciously override.
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People sneeze for many reasons and in many ways. One of them is to protect your airways from irritants and infectious disease.
It can stretch your mind to ponder what’s really out there.
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Astronomers know a lot about what’s in outer space – and think it’s possible it never ends.