I’m the Universe, hear me roar.

The cosmos has plenty of terrifying Lovecraftian features, but one of my favourites is the Space Roar. There is a loud radio signal, described as a constant hiss, that seems to pervade the cosmos. It is louder than the radio signature of radio galaxies, and it is without explanation.

PodcAstroholic – Why Is Pluto Not A Planet?

In this PodcAstroholic we answer the question "Why is Pluto not a planet?" Longer discussion in the vlog

A Ghostly Cradle Of Stars

If you wonder where we came from and how we got here, there's a step we are quite confident on. About 5 billions of years ago, before the Sun shone a single ray all...
Credit: Wikicommon

How hot or not is a Black Hole?

Short Answer - the temperature of a black hole is inversely proportional to its mass. For a black hole with the same mass as our Sun the temperature is 60 billionths of a degree kelvin.

More On Gravitational Waves

In a previous post, we discussed the groundbreaking discovery of gravitational waves and it's importance for science as a whole. Now LIGO has observed another detection, and it has the incredible feature of being the...
Credit: Stephen van Vuuren

Something out of Nothing

If the 1st Law of Thermodynamics is true how could the Universe begin from nothing? To answer this question we need to remember that nothing is a global term and not a local one. Vacuum states exist...

What’s the speed of Gravity?

For all intents and purposes gravity travels at the speed of light but it is very hard to measure, and so far we have no direct model-independent measurement of the speed of gravity. Physics has...

Shopping for rings

I have a space question. I know about the Roche limit but is there an upper limit to how big a ring can get compared to its planet? Asked by Dan Of course there are limits, the Universe is all about limits! But they're not as strict as one would think. We have found an object in 2012, J1407b, with a ring system 200 million kilometres in diameter. If the rings were centred on Earth they would cover the inner solar system all the way to the orbit of Mercury on the opposite side of the Sun.

All about the Asteroid Belt

What does it actually look like in the asteroid belt? Is it anything like as dense as is shown in films? Or is it more like you can see one or two rocks in...

Stars of the Future

If the universe continues expanding forever, how long until it's too diffused to allow star formation? How many generations of stars will that mean the universe has? How will the elemental make-up of these...