Tag Archives: gravity

Dark Energy – 60 Second Adventures in Astronomy (9/14)

60-Second Adventures in Astronomy. Number 9: Dark Energy. Why is the universe expanding? Albert Einstein was absolutely certain the universe was stable but he couldn’t work out why his snazzy new relativity equations suggested it was contracting, so Einstein figured space must have an inbuilt tendency to fling itself apart, which would balance out the… Read More »

Dark Matter – 60 Second Adventures in Astronomy (8/14)

60-Second Adventures in Astronomy. Number 8: Dark Matter. What’s the matter with dark matter? Fritz Zwicky was a Swiss astronomer who could probably get you 81 points on a triple word score in Scrabble. In the 1930s he noticed that galaxies within clusters were zooming around far quicker than their mass would logically dictate, so… Read More »

Black Holes: Crash Course Astronomy #33

As we’ve seen over the past few episodes, a lot of really epic stuff happens when a star dies. If the star’s core is less than 1.4 times the mass of the Sun, it becomes a white dwarf—a very hot ball of super-compressed matter about the size of the Earth. If the core is heftier,… Read More »

The Gravity of the Situation: Crash Course Astronomy #7

We live — and stop me if I’m going too fast — on a planet. I mean, sure, duh. But this isn’t the natural state of the Universe; or, at least, it’s not the way things usually are. Most of the Universe is pretty empty — that’s why we call it “space” — and if… Read More »

Black Holes – 60 Second Adventures in Astronomy (12/14)

60 Second Adventures in Astronomy. Number twelve, Black Holes. DIY tip 34 – How do you make yourself a black hole? A black hole occurs when something has so much mass in such a small space, that nothing can escape its gravitational pull – not even light. In 1931 Subrahmanyan Chandrasekhar calculated that, if a… Read More »

Gaia and the Killer Asteroids – 60 Second Adventures in Astronomy (14/14)

60 Second Adventures in Astronomy. Number fourteen, Gaia and The Killer Asteroids. If Hollywood has taught us one thing it’s that an asteroid crashing into the Earth is not exactly something to look forward to. The asteroids most likely to attack us are the Aten and Apollo asteroids – the ones with an orbit closest… Read More »

Amazing astronomy: How neutron stars create ripples in space-time | Michelle Thaller

A few decades ago we actually saw explosions in the sky somewhere out in space that we really didn’t understand at all. They gave intense bursts to something called gamma rays. And gamma rays are the highest energy kind of light that is possible. Now you probably heard of, you know, ultraviolet rays from the… Read More »

Exoplanets – 60 Second Adventures in Astronomy (3/14)

60-Second Adventures in Astronomy. Number 3: Exoplanets. Like fussy holidaymakers looking for a home from home, astronomers are fascinated by finding planets similar to earth beyond our solar system. But planets outside our solar system, known as exoplanets, are difficult to spot because they get lost in the glare from the star they orbit, like… Read More »

Astronomers Discovered a Forbidden Planet But Have No idea Why It Exists

According to astronomy, planets the size of Neptune couldn’t possibly form and sustain any kind of atmosphere while orbiting their parent stars at a close proximity. Well, forget what I just said, — because I didn’t quite understand any of it either – but last year, astronomers found exactly this kind of planet! And it’s… Read More »

Tides: Crash Course Astronomy #8

Y’know, if Shakespeare had been an astronomer, he’d have said that “there is a tide in the affairs of the Universe, and on such a full sea are we now afloat.” He would’ve been right. You might just think of tides as the ocean going in and out every day, but in fact what astronomers… Read More »