Get set for a nice crescent Moon for the start of the weekend and boy, isn’t the sky going to be great for stargazers! This is the month they say our Aussie skies are at their best, especially away from city lights. With bright moonlight lasting till almost midnight it’s a good time to test out a new telescope or go panning around looking for star clusters. Head just to the right of the Southern Cross and do a sky sweep, then tell me that wasn’t good advice. See all those bright spots? Yep, brilliant clusters and gas clouds. By the way, anything except full moon nights are great for telescope viewing.
It’s hard to imagine Earth without a moon isn’t it? Life itself might have evolved from the ocean to land thanks to tides induced by the moon’s gravity. Astronomers believe a body as big as Mars once smacked into our infant Earth, breaking off a large piece which fell into orbit, eventually forming into the moon we see today. A lot of that debris fell back on the Earth too making huge craters which, over time, have been smoothed over by volcanism. You know what? Somebody’s actually weighed the Earth! True. The Earth has a mass of 6, million, million, million, million kilograms, or, if you prefer, 6 sextillion tonnes. Try that one at your next trivia night.
In the early evening Saturn with its beautiful ring system is readily visible high in the western sky. Even in small telescopes it’s an amazing sight and never fails to impress. Talking about stunning views, check out what’s hanging low in the eastern sky before sunrise. That bright ‘star’ you see is in reality our sister planet Venus, also known as the evening star. This week Venus is absolutely spectacular and already generating the odd UFO report or two. If you stare at it awhile it appears to move around or wobble. Try it.
Hey, while you’re in the mood, why not take time out and try my favourite celestial sport, meteor watching. The Perseids meteor shower makes an appearance in the coming week and after midnight a few decent meteors should flit across the starry sky each hour in a spooky display. The meteors peak on August 12 and are produced by debris from an earlier passing of Comet 96P/Machholz.
Perseids typically have fast and bright meteors and are known to create the odd fireball or two with flaming tails that streak across the dark early morning sky. More northern centred this year, the radiant may be a little low, but still worth a try. Fireballs are meteors that actually start to melt and catch on fire! Are they dangerous? The simple answer is no, not at all.
Nobody has ever been injured from watching meteor showers. Travelling at speeds of up to 60 kilometres a second, most meteors quickly vapourize 50 kilometres above the ground. Almost all are destroyed in this process – the rare few that survive and hit the ground are known as meteorites. The largest ever found was found in Hoba, Namibia. It weighed 60 tons!
Now for an after dinner treat. Want to see the space station passing over your place this week? Well, if you go to www.spotthestation.nasa.gov/sightings and enter your location a chart will come up for the entire week giving dates and times to go and look. Simple huh? There’s also a great aussie app you can download called ISS Flyover. Just imagine, when you see the space station remember it’s moving at 28,000 kilometres an hour and astronauts onboard see 16 sunrises and 16 sunsets every day! What a cool job!
Did you know that when the station crew return to earth they look forward to a good long hot shower. In space you can’t do that easily. In fact, astronauts wear the same underwear for the entire mission! You don’t sweat as much in space. Spacesuits are fitted with ‘nappies’ so that astronauts can work outside for long hours especially during spacewalks. They hardly shower at all. You have to remember, in space water doesn’t fall down, it falls up and ‘sponge baths’ are the norm. They use wet cloths for washing and special shampoo for their hair which doesn’t require water.
You know, I get a lot of people telling me they only have a small telescope and want to know if it’s any good to stargaze with. My answer – sure can! Smaller telescopes are capable of doing a lot more than you imagine. I started out with a telescope you could fit in your pocket! Remember, cheapie telescopes under about $200 are made to a price, not a quality, and the trade-off is in the eyepieces.
If your cheapie telescope isn’t giving you satisfactory views I bet it will if you get a good quality brand eyepiece from your camera store. Around $30 -$50 should do it. Stargazers can take it to the next level with some special software that mimics the night sky. I frequently bring my laptop into the field with me to use Stellarium, a free program that gives a real time view of the sky and labels nearby stars. You can recreate the night sky from almost any era in history, and move forward hundreds of years to view an eclipse yet to happen! Download it, you won’t be sorry.
David Reneke is an astronomy writer, lecturer, broadcaster and media personality. Get David’s free astronomy newsletter and a free 323 page e-book called ‘The Complete Idiots Guide To Astronomy. Visit the webpage: www.davidreneke.com