Scientists are trying to work out the number of galaxies in the whole of our universe, and so far they have surveyed about 3% of our sky. They have found around 3 million galaxies in that section of the sky, so if the number of galaxies is the same around the whole of the sky, there is around a hundred million galaxies in the universe. There are around a hundred million stars in a galaxy.  So, this means that there are around a hundred million galaxies, in each of which are a hundred million stars. This means there are 10,000,000,000,000 (or ten quadrillion) stars in the universe. Each star has “on average … at least 1.6 planets.” That’s 16,000,000,000,000 (16 quadrillion) planets out there. And people say we’re the only ones to exist. - There’s actually something called the Drake Equation which estimates the number of extraterrestrial civilisations in just our Milky Way galaxy, and you can find more information about that here.

Scientists are trying to work out the number of galaxies in the whole of our universe, and so far they have surveyed about 3% of our sky. They have found around 3 million galaxies in that section of the sky, so if the number of galaxies is the same around the whole of the sky, there is around a hundred million galaxies in the universe.

There are around a hundred million stars in a galaxy. 

So, this means that there are around a hundred million galaxies, in each of which are a hundred million stars. This means there are 10,000,000,000,000 (or ten quadrillion) stars in the universe. Each star has “on average … at least 1.6 planets.”

That’s 16,000,000,000,000 (16 quadrillion) planets out there. And people say we’re the only ones to exist.

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There’s actually something called the Drake Equation which estimates the number of extraterrestrial civilisations in just our Milky Way galaxy, and you can find more information about that here.

An amateur astronomer has recorded images of the out-of-control US satellite as it tumbles back to Earth.

Thierry Legault, from Paris, captured the video as the satellite passed over northern France on 15 September.

The US space agency says the risk to life from the Upper Atmosphere Research Satellite (UARS) is 1 in 3,200.

Mr Legault, an engineer, used a specially designed camera to record the tumbling satellite through his 14-inch telescope, posting the footage on his Astrophotography website.

Nasa says that most of the satellite will break or burn up before reaching Earth.

But scientists have identified 26 separate pieces that could survive the fall through the atmosphere. This debris could rain across an area 400-500km (250-310 miles) wide.

Robust, spherical satellite components such as fuel tanks are often most likely to survive the fiery plunge to Earth, say space experts.

This is an infrared picture of the galaxy. It’s 300 billion light years across. Scientists can zoom into the centre of the galaxy, and see high velocity stars orbiting a dark space, showing the location of a black hole. It’s hot gas orbiting a massive black hole (called an accretion disk), and so the light coming from that region shows astronomers precisely where the black holes are. A few pixels on your computer screen cover an area 27 million miles across, and the black hole they orbit is 4 million times the weight of our own sun. This is why I want to take astrophysics. Because I want to try and understand stuff which no one has yet to understand. I want to find out the very meaning of our world; what made it, why it came to be and exactly what is in everything. It’s literally going to the edges of the universe.

This is an infrared picture of the galaxy. It’s 300 billion light years across. Scientists can zoom into the centre of the galaxy, and see high velocity stars orbiting a dark space, showing the location of a black hole. It’s hot gas orbiting a massive black hole (called an accretion disk), and so the light coming from that region shows astronomers precisely where the black holes are. A few pixels on your computer screen cover an area 27 million miles across, and the black hole they orbit is 4 million times the weight of our own sun.

This is why I want to take astrophysics. Because I want to try and understand stuff which no one has yet to understand. I want to find out the very meaning of our world; what made it, why it came to be and exactly what is in everything. It’s literally going to the edges of the universe.