Night visions, the sky 10 billion years ago and unexplained sounds from around the world

Good old days: the view from an Earth-like planet 10 billion years ago. (Courtesy: NASA/ESA/Z Levay (STScI))

By Hamish Johnston

This week’s Red Folder is inspired by a vision I had last night while I was putting out the garbage bins. I happened to look up at the sky just as the International Space Station (ISS) was travelling over Bristol. It was a very bright and impressive sight as it zipped overhead before disappearing at the eastern horizon. If you happen to be on an arc through northern Europe between Penzance and Poznań, you should also have a great view of the ISS this evening; you can find out when and where to look at the ISS Astroviewer website.

The ISS is one thing that you would definitely not see if you could look at the sky as it was 10 billion years ago – but have you ever wondered what that view would be? Zolt Levay at the Hubble Heritage Information Center has, and the above image is his vision of what the sky would look like from a hypothetical planet within a Milky Way-like galaxy 10 billion years ago. The work was inspired by a new collection of nearly 2000 images of galaxies as they appeared at that time in the history of the universe. Taken by a number of different telescopes including Hubble, “the new census provides the most complete picture yet of how galaxies like the Milky Way grew over the past 10 billion years into today’s majestic spiral galaxies”, according to NASA.

The pinkish clouds in Levay’s image are clouds of gas that harbour newborn stars and the light-blue regions are clusters of young stars. Alas, such a sight was never seen from Earth, which along with the Sun was formed much later in the history of the Milky Way once the frenzy of early star formation was over.

Finally, it is often said that we know more about our near neighbours in the solar system than we do about what lurks below the oceans here on Earth. Over on mental_floss, Caitlin Schneider has put together a collection of nine unexplained sounds from around the world, several of which were recorded by hydrophones in the oceans. By far the spookiest is called “Julia” and you can listen to it in the video clip above. What could it be?