Google has announced Google Sky, a new feature in Google Earth that lets you browse the entire night sky. Download the latest version of Google Earth, and you'll find a new button on the toolbar, which switches you to the sky view.
Sky mode includes clickable layers containing the complete Yale Bright Star Catalogue, Messier Catalogue and Dreyer's New General Catalogue of nebulae. Deep sky objects, such as the Horsehead Nebula, are accompanied by handy explanatory notes from Wikipedia. Other layers include a showcase of photos from the Hubble Space Telescope and a tour of stellar evolution, from star formation in a molecular cloud through to death as a planetary nebula.
Let me introduce you to the Flamsteed Astronomy Society at the Royal Observatory Greenwich (ROG). I’ll be reporting on the Flamsteed’s activities and plans regularly in this blog.
The Flamsteed is an amateur astronomy society based at the ROG and National Maritime Museum (NMM), Greenwich. It’s named after the first Astronomer Royal, John Flamsteed. We feel very privileged to meet on a site of such historical significance and enjoy the superb facilities of the ROG and NMM. We now have just over 100 members who represent the full range of experience and interests in astronomy. Many are beginners and we pride ourselves that the Flamsteed programme is very enjoyable for people just starting out to learn more about the subject. Several members are professional astronomers, and we have access to the full-time astronomy staff at the ROG.
The Flamsteed programme includes first-class talks by ROG staff and other eminent speakers. The talks cover all aspects of astronomy including cosmology, recent discoveries and space missions, as well as the history of the subject. Talks take place monthly between September and May in the NMM Greenwich. We also arrange visits to the new Peter Harrison Planetarium, sessions with the 28-in Great Equatorial Telescope at the ROG, and telescope workshops on using small scopes. Observing meetings take place using members’ own equipment, both on Blackheath SE3 and at darker sites in Kent. Most recently we met in Kent for the Perseids meteors.
One aim of the Society is to make donations to help the educational work at the ROG. We donated an H-alpha solar telescope, and volunteers from the Society use it to stage public solar viewings at the ROG on weekends and holidays when the weather’s clear. We also arrange visits to outside locations, for example, most recently to Jodrell Bank; last year to Rutherford Appleton Labs, and the Paris Observatory.
Our new season starts on September 1st. You can find full details of the Flamsteed’s upcoming programme, and reports from previous events and meetings, on the Flamsteed website. There’s also information on subscriptions and how to join, and you can be sure of a warm welcome, whatever your interest in astronomy or level of experience.
Photo: NASA/JPL-Caltech
The Galaxy Evolution Explorer (GALEX), a space-based observatory surveying distant galaxies in ultraviolet light, has made an important discovery in our own Milky Way galaxy. Mira, a red giant star about 400 light years away from Earth in the constellation Cetus, has a tail of gas and dust that stretches 13 light years through space (this means that light emitted by Mira now won’t reach the other end of its tail until the year 2020). A tail like this has never been discovered around a star before.
Thousands of millions of years ago, Mira was a star like our own Sun, a main sequence star. When main sequence stars grow old, they expand to enormous size and cool. Mira has reached this stage, becoming a red giant which is gradually blowing its outer layers of gas away into space. Over time, it will become a planetary nebula and eventually die as a white dwarf – the hot, glowing remnant of a dead star’s core.
Mira is unusual, among stars in the Milky Way, in that it is moving very quickly with respect to the stars around it. It moves through space at 130 km/s, or 291,000 miles/hour. It is also a binary star – it has a white dwarf companion star (Mira B) and the pair of stars orbit slowly around each other as they move through space.
Mira’s tail is made of gas and dust which has been ejected by the star over the last 30,000 years, forming a wake behind it as it moves through the interstellar gas and dust of the Milky Way. Studies of the chemical composition of the tail, at different distances from the star, will offer a fascinating opportunity to learn about the processes of stellar evolution and mass-loss in red giant stars.
Perseid
Originally uploaded by Leviathor
It seems like the Perseid meteors put on a good show on Sunday night. I saw a couple from my back yard, even against the bright lights of South East London.
Several people have posted photos of the Perseids on Flickr. Visit our Flickr favourites page to see a few that caught our eye, including the nice photo of a Perseid shown above.
The BBC has a round-up of comments about the Perseids from people around the UK.
space station and shuttle
Originally uploaded by gribley
Look up in the evening and there’s a chance, at the moment, that you might see the International Space Station (plus space shuttle Endeavour) pass overhead.
If you want to know when the ISS is going to be visible, have a look at Above London on twitter. This service posts notifications of space station visibility and Iridium flares, flashes of light caused by the reflection of sunlight off of satellite solar panels and antennas.
Also on twitter, and reproduced on this blog’s homepage, is the Jodrell Bank telescopes feed, which updates to show which objects are currently being observed by the Jodrell Bank radio telescopes.
Star chart courtesy of the European Space Agency
The annual Perseids meteor shower reaches its peak this weekend, with 80-100 meteors per hour predicted before dawn on Monday 13th August.
Annual meteor showers occur when the Earth’s orbit passes through the orbit of a comet. Dust that the comet has left behind is swept up by the Earth and burns up in its atmosphere. We see these tiny particles burning up as shooting stars in the night sky.
The Perseids meteor shower is a bright shower associated with comet Swift-Tuttle, which last passed close to the Sun in 1992. Perseid meteors can be seen during late July and early August, with a peak around the 12th of August. To best see the meteor shower, go outside after 11pm and look for the constellation Perseus in the northeast. In clear weather, you should be able to spot a meteor every few minutes or so. Most meteors are flashes of light lasting less than a second, but some may be more dramatic and leave more persistent trails.
More information about this meteor shower can be found in the Royal Observatory’s Perseids fact file.
If you do see some meteors, please let us know by leaving a comment.