BSC - Saturday 12 December 2009
Hello Fellow OCA club members!
This Saturday I plan to open the gate at 4:15 pm, about a half hour before the sun sets. The weather report for this Saturday indicates that Orange County will be getting lots of rain, but we are several days off and I am hoping the reports are wrong. The 3rd Quarter Moon will not rise until about 4 am giving us dark skies. First time visitors might want to get to BSC while it is still light so they can find their way down the dirt road and into the parking area. Remember that you take the 2nd farm gate on the left after turning on Black Star Canyon Road. If you come in after dark, you should drive in with your headlights off!!! The dirt road will be marked with red flashers and you can hold a flashlight out the driver’s window to light up the road directly in front of your car.
The ISS (International Space Station) will make a few visible morning passes this week but none in the evening at BSC. The HST (Hubble Space Telescope) will only make morning passes this week so also won’t be seen Saturday evening. We won’t see any Iridium flares this Saturday either but I am sure we will see a few satellites pass over as we are looking up in the sky.
~Mercury (Mag -0.5) sets about 6 pm and could be seen this Saturday evening where it will be 5 degrees high 30 minutes after sunset. It is 112 million miles from Earth in constellation Sagittarius. Mercury rises about 8:15 am so can no longer be seen just before sunrise.
~Venus (Mag -3.8) sets about 4:15 pm and rises about 6 am, in constellation Ophiuchus and remains lost in the sun’s glare all month. It is now about 157 million miles from our planet Earth.
~Mars (Mag -0.2) is now in Constellation Leo traveling eastward getting closer to Earth and is now about 83 million miles away. Mars sets about 11 am and doesn’t rise until around 9:15 pm so should be seen this Saturday evening at BSC. Look for it’s shrinking north polar cap this month as it is tilted in Earth’s direction. You might also be able to detect the dark triangular albedo feature Syrtis Major which lies near the center of the planet.
~Jupiter (Mag -2.1) rises about 11 am in constellation Capricornus so the big planet will be seen lower in the sky as the sun sets this month and Jupiter sets about 9:40 pm. It now is about 497 million miles from Earth and getting further every day. The big Red spot will not be visible Saturday evening. Ganymede (the largest moon in the entire solar system) will be the moon farthest to the west with Europa just a bit closer to Jupiter. Moon Callisto will be far to the east of Jupiter while moon IO will be passing in front of Jupiter and become visible to the east about 8 pm.
~Saturn, (Mag 1.0) sets about 1 pm Saturday in constellation Virgo so will not be visible at BSC Saturday evening. It is about 902 million miles away getting closer to Earth. It can be seen in the early morning sky as it rises about 12:40 am. We will now see the northern side of the rings for the first time since 1996.
~ Uranus (Mag 5.8) will rise about 12:20 pm in constellation Aquarius this week so can be seen high in the sky Saturday evening until it sets about midnight. It shows up as a blue-green disc in a telescope and is about 1.858 billion miles away moving farther from Earth. This planet reached opposition September 17th.
~ Neptune (Mag 7.9) will be in constellation Capricornus about 2.827 billion miles away this week slowly moving farther from Earth. It is seen as a bluish disc in a telescope and we should see it this Saturday as it rises about 11 am and sets about 9:45 pm. It will be just a few degrees behind Jupiter along the Ecliptic.
You can expect to see 100 meteors an hour, at dark sky site, from the Geminid meteor shower which peaks the morning of December 14th. The radiant is near bright star Castor and the meteors are from tiny particles from Asteroid 3200 Phaethon, which is probably the necleus of a dead comet, that passed through the Earth’s orbit. We may see some of that activity late at BSC this Saturday evening.
A second shower from the Ursids meteor shower this month peaks before dawn on December 22nd.
Comet C/2007 Q3 (Mag 10.2) will be just a few degrees from globular cluster M53. It is now about 231 million miles away from Earth in constellation Coma Berenices. Notice how this comet brightens towards it’s center in a noticeably different way than M53 does.
Other comets are even dimmer so would be next to impossible to find in any of our scopes.
Minor Planet 1 Ceres (Mag 8.9), the very first asteroid ever discovered, is now floating near Libra. It will not be visible Saturday evening but might be seen early in the morning just before dawn. This asteroid has a period of 4.6 years and is about 332 million miles away. It was discovered back in 1801 and is the largest asteroid we have found, having a diameter of 580 miles.
Minor Planet 3 Juno (Mag 8.5) reached opposition in September and is brighter than it has been since 2005. It is only 1/4th the diameter of Ceres yet was one of the first 4 asteroids discovered. It can be found toward Cetus this month about 10 degrees from Uranus. It is only about 153 million miles from Earth getting further every day and has a period of 4.36 years.
Minor Planet 4 Vesta (Mag 7.6) is the 2nd most massive object in the asteroid belt with a diameter of just over 329 miles. It is the brightest of all the asteroids and can be found along the bottom of Leo the Lion about 10 degrees from Regulus. It is now about 190 million miles from Earth and has a period of 3.63 years.
Lets look for some objects this month around Casiopeia, the Queen that can help us find Polaris when the Big Dipper is not visible.
Open Cluster M52 (Mag 6.9) is found along a line formed by end beta star Caph and alpha Cassiopeiae at the same distance as those stars are apart. It is 3,000 light years away and spans 11 light years. This cluster contains at least 100 stars, the brightest about magnitude 8.2, that Messier observed clear back in 1774. It’s age is estimated to be 35 million years old.
Open cluster M103 (Mag 7) is found just 1 degree away from Delta Cassiopeiae which is the middle star in the lower “W”. It is thought to be 8,500 light years away and spans 15 light years. The cluster contains about 25 stars, the brightest being magnitude 10.6 and it’s age is estimated to be 22 million years old. Messier observed this object in 1781.
Plenatray Nebula M76 (Mag 11) is called the “Little Dumbbell” as it looks like a little two-lobed object resembling a dumbbell weight. It is not quite a degree away from 3.5 magnitude star Phi Persei and there is a conspicuous bright reddish star about 10’ away. Just look at the end of the 2nd Andromeda strand. It is 8,200 light years away and spans 5 light years. This nebula that Messier observed back in 1780 looked to him like some small stars containing nebulosity.
Don't forget to bring your gloves, coats & sweaters because it will get very cold as the sun sets and as the night approaches midnight when we close. After you set up your telescope, there are three picnic tables where you can sit and eat food you might bring, while waiting for it to get dark. Please remember to cart off all your trash as there are no garbage cans at BSC. Hope to see you there.
Your OCA star party host,