Articles on Earth

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The extinction of dinosaurs is one of the many periods of mass extinctions on earth. www.shutterstrock.com/Jaroslav Moravcik

5 periods of mass extinction on Earth. Are we entering the sixth?

Scientists believe since 2010 we have entered the sixth period of mass extinction. CO2 emissions will change the lives of plants and animals in the next three to four decades.
Sunrise over Brisbane. Flickr/Sam Petherbridge

It’s going to be a long summer’s day today, seriously

A solar day is a measure of how long it takes the Earth to rotate from one noon to the next, and today’s summer solstice also happens to be the longest solar day of the year.
The mass of the Earth is big enough that the gravitational force it creates can pull the hard shape of ice, rock and metal into a sphere. NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center

Curious Kids: Why is the Earth round?

Imagine the Earth pulling everything it is made up of, all of its mass, towards its centre. This happens evenly all over the Earth, causing it to take on a round shape.
Lasers being shone from the European Southern Observatory’s Very Large Telescope in Chile. These lasers help remove the twinkles in the night sky and help astronomers see stars clearer on Earth than ever before. F. Kamphues/ESO

Curious Kids: Why do stars twinkle?

How exactly do the stars twinkle in the night sky? As it turns out, the answer is full of hot air… and cold air.
Earth, shot from space, as it absorbs and reflects rays of light coming from the Sun - the same white-looking rays that give our sky its colour. NASA

Curious Kids: Why is the sky blue and where does it start?

Some people think the sky is blue because of sunlight reflected off the ocean and back into the sky. But that’s not the real reason.
Between the Earth and the moon: An artist’s rendering of a refueling depot for deep-space exploration. Sung Wha Kang (RISD)

Mining the moon for rocket fuel to get us to Mars

To get us to Mars and beyond, a team of students from around the world has a plan involving lunar rovers mining ice and a space station between the Earth and the moon.
A bison on its way in the Bialowieza forest in Poland. By Herr stahlhoefer - Own work, Public Domain,

Do passages in the Bible justify cutting down forests?

In countries that identify predominantly as Christian, scripture and its interpretations carry serious sociopolitical weight.
Have we really discovered other “Earth-like” planets orbiting around other stars? Understanding what we do and do not know about exoplanets is the key to answering this question. ESO/L. Calcada/N. Risinger/Reuters

Until we get better tools, excited reports of ‘habitable planets’ need to come back down to Earth

Over the last 20 years, advances in the field of exoplanet discovery have excited the imaginations of scientists and enthusiasts alike. But we’re in position to know yet whether a planet is habitable.

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