Carnival of Space No 164

There's always something new and exciting at the Carnival of Space. The latest is hosted by nextbigfuture.com. Call in and enjoy the show.

Aliens, vampires and dragons: six startling stories of super science

The latest issue of Astronotes will be available soon, here is a taster for this month's staggering stories.

1. Are aliens lurking on a Saturnian moon? Sinead McNicholl investigates these ominous rumours.

2. The day the Chinese navy saved the Earth from a cosmic dragon! The truth is revealed by Martina Redpath.

3. White-hot comet lumps to bombard Planet Earth! Mary Bulman issues a stark warning.

4. Vampires sighted in Armagh Planetarium! Tracy McConnell reports on the shocking truth.

5. Horrible things in hyperspace? Colin Johnston exposes the danger.

6. A strange object in space is the subject of our Image of the Month.

Dare you explore what lies within these pages?

The Space Review: The man who painted my future

The Space Review: The man who painted my future

An interesting article I thought I'd share, I still have that same book which inspired the author of this piece.

Carnival of Space No 163

The latest Carnival of Space is here already! And it's as great as ever! You can find it at Emily Lakdawalla's blog for the Planetary Society. Enjoy!

A planet that thinks it's a comet!

Some 150 light years from Earth in the constellation of Pegasus lies the star HD 209458 and its planetary system. The star is almost a clone of our own Sun, but one its planets is completely unlike anything in our Solar System.

The exoplanet HD 209458b has a mass more than 200 times Earth’s and has a diameter greater than Jupiter’s. It orbits its star at about an eighth of the distance Mercury orbits the sun, so the exoplanet takes only 3.5 days to complete an orbit. This proximity to a star means that the planet is hot, perhaps 1000°C, hence it is classed as a “hot Jupiter”. Note that it will not be as hot as this everywhere; the planet is tidally locked to its star, having one side in permanent blazing day and one in an eternal cooler night.

The temperature differential of this planet was expected to mean that it has a violently seething atmosphere (which we know contains carbon dioxide, water vapour and methane). This has been proven: wind speeds of 5000 to 10 000 km per hour have been observed. Perhaps even more dramatic is the fact that the atmosphere is leaking into space, with stellar winds pushing the escaping material into a long stream behind the planet. HD 209458b must look like a gigantic comet! This was long expected but now has been proven thanks to observations with the HST. (The artist’s impression shows it viewed from a hypothetical moon, we have no images of this planet.)

In billions of years, HD 209458b will entirely lose its atmosphere, and be a barren sphere of rock and metal (a so-called cthonian planet), arid on one side, frigid on the other.

Image credit: NASA, ESA and G. Bacon, STScI

Moon Hoax? Apollo 15 Rover Traverse

This is a nice little movie made during the Apollo 12 mission on a traverse of the Hadley-Apennine region.

Starfog

It is difficult to look at this newly-released Hubble Space Telescope image of the nebula NGC 2467 without thinking about what it would be like to fly through it.

It is easy to imagine floating through a beautiful softly glowing mist, something like the Mutara Nebula, scene of Kirk and Spock's finest hour. Alas the truth is unlikely to be as dramatic. The (mainly hydrogen) gas and dust in this star-forming region is thin. In each cubic centimetre of the nebula there are only a thousand or so particles (the corresponding value in the solar System would be about 1 particle per cubic centimetre). Also the light emitted would be faint and colourless to the naked eye. It appears so spectacular in this image because it is made with a lengthy exposure of more than half an hour.

This nebula is located about 13 000 light years from Earth in the southern constellation of Puppis (the Ship's Stern or sometimes the Poop-deck). Most of the energy stimulating the nebula's glow comes in the form of harsh ultra-violet radiation from the bright star in the upper centre of the image.

Another beautiful and thought-provoking image from the HST!


Image credit: NASA, ESA and Orsola De Marco (Macquarie University)