ohscience:

stellar spire, eagle nebula

ntldnlldkns:

this book will fill the void of a five month summer holiday

peteuplink:

Giant Galaxy NGC 6872 
Image Credit: Sydney Girls High School Astronomy Club, 
Travis Rector (Univ. Alaska), Ángel López-Sánchez (Australian Astronomical Obs./ Macquarie Univ.), Australian Gemini Office

Must read of the week

How to identify my favourite planet, Venus in the night sky

Venus is by far the easiest planet to see with the naked eye. It shines with a brilliant white light, although some claim that it has a slightly bluish tint. It is the brightest planet in the night sky; when visible, it outshines all the other planets - and indeed all the other stars in the night sky - at which time only the Sun and the Moon are brighter.

Venus has a cycle of alternating morning and evening appearances, and is popularly named The Morning Star when seen in the Eastern sky before sunrise and The Evening Star when seen in the Western sky after sunset. Each apparition lasts for several months, during which time the planet slowly moves away from the Sun, reaches its greatest elongation (around 46 degrees away) and then slowly moves back towards the Sun, eventually disappearing into the morning or evening twilight (remaining visible for most of the time). At greatest elongation, Venus rises/sets some 3 hours before/after the Sun.

When seen through a telescope, Venus shows phases much like the Moon. Its thin crescent phase can be discerned in good quality binoculars when it is in the nearer part of its orbit to the Earth (i.e. when it is closing in on the Sun in the evening sky, or pulling away from the Sun in the morning sky). Some keen-eyed observers have even claimed to see the crescent with the naked eye! However, Venus’ brilliance produces considerable glare when seen against a dark sky, so when using optical aid, it is best observed in bright twilight.

When shining at its greatest brilliancy, Venus can cast faint shadows at night, and it can even be glimpsed in daylight (given a clear, haze-free sky and provided that the planet is well clear of the Sun). The best way to see Venus in daylight is when it is a ‘Morning Star’, when it can be continually observed through to sunrise and beyond.

Venus comes closer to the Earth than any other planet - to within 26 million miles (41 million kms). Its brilliance is largely due to the high reflectivity (albedo) of its clouds, which perpetually obscure the view of the planet’s extremely hot surface.

Credit to http://www.nakedeyeplanets.com/

Saturn and its rings now on full display

The ringed planet puts on quite a show in April. Often considered the most beautiful world, Saturn reaches opposition — the point in its orbit when it lies opposite the Sun, and thus brightest in our skies — on the night of April 3/4. It will rise in the east at sunset, reach its highest point above the southern horizon at local midnight, and set at sunrise.

As April begins, Saturn will be the only planet visible before midnight. The best views occur later in the evening as it climbs southeast, with prime viewing happening at its maximum altitude, due south and about halfway to the zenith from mid-northern latitudes. “It’s always a lovely sight, but Saturn will look particularly stunning this month,” says Astronomy Senior Editor Richard Talcott.

Credit to http://www.astronomy.com/

Moon phases for April 2011