What if Mars Attacks?

Whenever a conversation flairs up with my friends about space, planets other than our own and the possibility intelligent life elsewhere in the galaxy, I am always afraid that someone will over hear our conversation and think we are inner city equivalents of a stressed dairy farmer from Iowa who claims to have been abducted and experimented on by aliens. Just to be safe I tend to keep my voice down during such conversations.

However over recent years since the observation of the first planet orbiting a star other than our own (extrasolar planets Continue reading “What if Mars Attacks?”

How many stars are there in the universe?

How many stars do you think there are in the universe? If you are anything like me, who has a rather casual knowledge of science, you’ll feel completely unqualified to even hazard a guess. If you were to try, you could be forgiven for getting it wrong because the answer keeps changing. Once upon a time, it was thought there was only one star (in the sense in which we understand it), and the things we saw were holes through which we could glimpse this light of heaven. Not so long ago it was thought there were infinite stars in an infinite universe (we now know that our universe is not infinite) and it seems that the answer was, until recently, 100 sextillion stars (it looks more impressive with the numbers actually written down: 100,000,000,000,000,000,000,000). This answer is rather out of date with the publication of a report in the journal Nature by Dr Pieter van Dokkum from the University of Yale (http://blogs.discovermagazine.com/80beats/2010/12/01/the-estimated-number-of-stars-in-the-universe-just-tripled/). It has been reported by van Dokkum that the number of stars in the universe is three times what we previously thought. The study’s main focus was the class of star known as Continue reading “How many stars are there in the universe?”