Saturnian Moons In Transit, courtesey of Hubble.
Scilly Stars 18th March 2009
Mercury was back briefly, and now before one gets chance to catch ones breath it’s gone again disappearing back into the sunrise. And if that’s not bad enough we’re about to lose Venus which still shines brilliantly in the west during evening twilight, but alas is getting lower every day. And it's changing rapidly as it swings toward inferior conjunction between Earth and Sun. In a telescope Venus is an eerily thin crescent, waning from 7% sunlit on March 14th to just 3% on the 20th. And it's big: nearly an arc minute from cusp to cusp, which is one 60th of a degree.
Some people have claimed they have resolved the thin crescent of Venus with the naked eye. If you want to try, look right after sunset in a bright sky before the planet's glare becomes a problem. To reduce the effects of your eye's optical aberrations, try looking through a small, round hole 1 or 2 mm wide in a piece of aluminium foil or cardboard. But hurry up because this is the last week that Venus will be with us, in a few days the planet will cross in front of the sun to re-emerge in the April dawn.
If your up early enough and have a clear view of the Eastern Horizon, which eliminates St Agnes, most of Bryher, Tresco and St Mary’s, so just St Martins really, there’s a fairly dim Mars showing very low in the sunrise glow. Look for it just above the east-southeast horizon, well to the lower left of much brighter Jupiter, about 30 minutes before sunrise. Or even better wait until the summer.
Jupiter a much better bet is getting a little higher in the dawn sky each week. Look for it very low in the east-southeast about an hour before sunrise. On March 22nd, Jupiter shines just to the left of the waning Moon. Although they look close together, Jupiter is actually 2,200 times farther away at the moment, and 40 times bigger.
Saturn is just past opposition and is glowing yellow and bright, low in the east at dusk; well up in the southeast by midevening; and highest in the south around midnight. And there was a quadruple transit of Saturn’s moons across the planet's face on February 24th? Hubble was looking, and very kindly has released the images. Which I’ve put on the blog along with some other equally riveting stuff.
But the big event this week, whether you’re interested in the stars or not, happens on Friday; the first day of spring; which this year is on the 20th rather than the 21st. At 3:44 am on Friday the North Pole flips from pointing away from the Sun and starts to point toward it for the next 6 months. 6 months of unbroken sunshine apart from a little light early morning drizzle on the 11th of July.
That was your night sky for the week ending the 24th March 2009.
Some people have claimed they have resolved the thin crescent of Venus with the naked eye. If you want to try, look right after sunset in a bright sky before the planet's glare becomes a problem. To reduce the effects of your eye's optical aberrations, try looking through a small, round hole 1 or 2 mm wide in a piece of aluminium foil or cardboard. But hurry up because this is the last week that Venus will be with us, in a few days the planet will cross in front of the sun to re-emerge in the April dawn.
If your up early enough and have a clear view of the Eastern Horizon, which eliminates St Agnes, most of Bryher, Tresco and St Mary’s, so just St Martins really, there’s a fairly dim Mars showing very low in the sunrise glow. Look for it just above the east-southeast horizon, well to the lower left of much brighter Jupiter, about 30 minutes before sunrise. Or even better wait until the summer.
Jupiter a much better bet is getting a little higher in the dawn sky each week. Look for it very low in the east-southeast about an hour before sunrise. On March 22nd, Jupiter shines just to the left of the waning Moon. Although they look close together, Jupiter is actually 2,200 times farther away at the moment, and 40 times bigger.
Saturn is just past opposition and is glowing yellow and bright, low in the east at dusk; well up in the southeast by midevening; and highest in the south around midnight. And there was a quadruple transit of Saturn’s moons across the planet's face on February 24th? Hubble was looking, and very kindly has released the images. Which I’ve put on the blog along with some other equally riveting stuff.
But the big event this week, whether you’re interested in the stars or not, happens on Friday; the first day of spring; which this year is on the 20th rather than the 21st. At 3:44 am on Friday the North Pole flips from pointing away from the Sun and starts to point toward it for the next 6 months. 6 months of unbroken sunshine apart from a little light early morning drizzle on the 11th of July.
That was your night sky for the week ending the 24th March 2009.
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