Tuesday, December 11, 2012

Early Conjunctions


A 6am start at -4 degrees is not always my idea of fun, but when I pulled up at the top of a nearby hill I was greeted with this spectacular view of a crescent Moon next to Venus, with the elusive planet Mercury burning through the low mist near the horizon. This slightly overexposed shot shows what is called "Earth Shine" on the lunar disc. Just as a full Moon reflect the sun back to us on Earth at night, the Earth also reflects light back to the Moon. In fact the Full Earth on the Moon would seen 100x brighter than a Full Moon on Earth - the result being the illumination of the "Dark Side" of the Lunar surface - easily seen with the naked eye, but more tricky to get on camera.




  With a shorter exposure we get the instantly recognisable crescent phase of the Moon. Tomorrow morning though this will have slid across the sky to just below Mercury, and at only ~2% illumination will be a fine sight ... if you can catch it!




This morning was more special than normal astronomically though (and the reason I hauled myself out of bed and into the cold) because you could see 5 planets at once with just your naked eye. Here we can see Mercury (bottom left), Venus (left of Moon), Earth (obviously!) and Saturn (brightest "star" towards the top right) as well as Jupiter (behind me, so not on the photograph). Venus shines at an incredible x23 the brightness of Mercury, but more impressive is Saturn - at 10x the distance away from us as the Sun is, it is still only x5 fainter than Mercury. Jupiter on the other hand is the largest planet in the solar system, and although very bright, is actually only half way to Saturn, which is itself only half way to Uranus. With most of the planets packed within the orbit of Jupiter, this just enhances the vast and desolate nature of our Solar System, yet that is nothing compared to our galaxy and the universe beyond.