We begin our story about 13.7 billion years ago, when all the space, matter, and energy of the known Universe was locked up in a volume less than one trillionth of the size of the point of a pen.
We begin our story about 13.7 billion years ago, when all the space, matter, and energy of the known Universe was locked up in a volume less than one trillionth of the size of the point of a pen.
2015 • Astronomy
Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into helium, and eventually helium into carbon (and also some oxygen and neon). When this happens they expand, get brighter, and cool off, becoming red giants. They lose most of their mass, exposing their cores, and then cool off over many billions of years.
29 • Crash Course Astronomy • 2015 • Astronomy
A science short by Sean Carroll, Modern physics reveals a universe with no need of a creator -- and a world where each person creates their own meaning.
2017 • Astronomy
Prof Jim Al-Khalili tackles the biggest subject of all, the universe, through a series of critical observations and experiments that revolutionised our understanding of our world. Part 1: Beginning Professor Jim Al-Khalili takes us back in time to tackle the greatest question in science: how did the universe begin? Uncovering the origins of the universe is regarded as humankind's greatest intellectual achievement. By recreating key experiments Jim unravels the cosmic mystery of science's creation story before witnessing a moment, one millionth of a second, after the universe sprang into existence.
1/2 • The Beginning and End of the Universe • 2016 • Astronomy
Earth has a companion in space so large that it rules our nights, our months, our ocean tides. Why Earth should have such a moon is one of the deepest mysteries of the Solar System. We tell the story of how the Earth’s satellite became the unlikely object of desire of the two Cold War superpowers.
4/8 • The Planets • 2004 • Astronomy
It was 30 years ago that the first space shuttle, Columbia, was launched. It was such a triumph of technology, engineering and organization that it's easy to forget the programme was primarily the product of an economy drive. The disposable Apollo missions had cost billions. A reusable craft was deemed more expedient.
Mercury is the closest planet to the sun. It has no atmosphere and is, as such, covered in craters. It's also incredibly hot but, surprisingly, has water ice hiding beneath its surface.
13 • Crash Course Astronomy • Astronomy
