How long is a day on Earth?

I'm going to ask you how long a day is on Earth, and you're going to get the haunting suspicion that this is a trap. Your instincts are right, it's a trap! The answer may surprise you.

Catching Earth at aphelion

Do you feel a little… distant today? The day after the 4th of July weekend brings with it the promise of barbecue leftovers and discount fireworks. It also sees our fair planet at aphelion, or its farthest point from the ...

A new spin on Saturn's peculiar rotation

Tracking the rotation speed of solid planets, like the Earth and Mars, is a relatively simple task: Just measure the time it takes for a surface feature to roll into view again. But giant gas planets Jupiter and Saturn are ...

Dance of the planets in the evening sky

Armagh Observatory reports that the next two weeks provide a rare opportunity to observe the planets Venus, Mars and Uranus in the western evening sky after sunset, and the bright planet Jupiter rising high in the East about ...

Earth's moon may not be critical to life

The Moon has long been viewed as a crucial component in creating an environment suitable for the evolution of complex life on Earth, but a number of scientific results in recent years have shown that perhaps our planet doesn't ...

Researchers reconstruct early stages of embryo development

Researchers at the University of Cambridge have managed to reconstruct the early stage of mammalian development using embryonic stem cells, showing that a critical mass of cells – not too few, but not too many – is needed ...

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