BSC Star Party Notice  – Saturday November 19th, 2011

Hello Fellow OCA club members!

This Saturday, I plan to open the gate around 4:15 pm, which is about a half hour before the sun sets. The weather report for this Saturday indicates that Orange County will be cloudy and maybe even some rain. So keep an eye on the OCA website where I will post a notice on the home page should the star party be cancelled for any reason.

The 3^rd quarter moon will start Friday so we should have fairly dark skies Saturday. 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 (the 1st farm gate is the Xmas Tree farm). 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.

Warning:  No Pets allowed!  (This is an Irvine Ranch Conservancy property rule)

Satellites:

The ISS (International Space Station) will not make any visible passes Saturday evening nor will the HST (Hubble Space Telescope). We will not see any Iridium flares Saturday evening either but I am sure we will see a few dim satellites pass over as we are looking up in the sky.

Planets & Pluto:

~Mercury, (Mag -0.2) doesn’t set until 6 pm so might be seen this Saturday evening low on the western horizon just 2 degrees under brighter Venus. It is about 92 million miles from Earth in constellation Ophiuchus, is 62% lit with a 6.7″ diameter disk.

~Venus, (Mag -3.8) might also be seen Saturday evening as it sets about 6:15 pm, shortly after the Sun, in constellation Ophiuchus, and is very bright. Venus is now about 141 million miles from Earth, is 90% lit with an 11″ disk.

 ~Mars, (Mag 0.9) is now in Constellation Leo setting about 1 pm so cannot be seen this Saturday evening as it does not rise until just before midnight. It is about 136 million miles away, just a 6.5″ disk so still too far away to see any detail on the planet without an 8″ or bigger telescope.

~Jupiter, (Mag -2.7) will rise about 3:45 pm in constellation Aries so will be high in the sky when the sun sets Saturday evening. It now is about 375 million miles from Earth getting a little farther every day. It will outshine any other object in the sky and moon Callisto will be far East of the big planet while moon Ganymede will be much closer. Then moon Europa will pass in front of Jupiter going east to west and moon Io will be to the west of Jupiter.

~Saturn, (Mag 0.8) sets about 3:30 pm Saturday in constellation so it cannot be seen at the BSC star party.  Saturn is about 980 million miles away slowly moving closer to Earth. It rises at 4 am so anyone wanting to go outside at that time can get a glimpse of Saturn before the Sun rises.

~ Uranus, (Mag 5.8) will be visible as the sun sets this week in constellation Pisces so can be seen Saturday evening at BSC. It will not set until 2:15 am and shows up as a small 3.7″ blue-green disc in a telescope. It is about 1.810 billion miles away, moving away from Earth. Uranus is easy to find using the two stars on the eastern edge of the Great Square of Pegasus and look along that line about 15 degrees south.

~ Neptune, (Mag 7.9) is in constellation Aquarius, about 2.782 billion miles away this week slowly moving farther from Earth. It is seen as a bluish gray 2.3″ disc in a telescope and we should be able to see it at BSC this Saturday evening, as it doesn’t set until 11:40 pm. The 2011 September issue of Sky & Telescope Magazine shows the path Neptune is following on page 53. That page also shows the path of Uranus.

 ~ Pluto, (Mag 14.1) sets at 7:45 pm and reached opposition and peak visibility in late June. It is 3.055 billion miles from Earth in constellation Sagittarius slowly getting farther from Earth. Since it is so dim, you will need a 10″ or larger telescope to see it visually at BSC until it sets at 7:45 pm.  The 2011 July issue of Sky & Telescope Magazine shows the path Pluto is following on page 64.

Meteors/Comets/Asteroids:

The November Leonid meteor shower peaked on the 17/18th when one might have seen up to 10 meteors per hour under favorable conditions. However, it was battling a 3^rd quarter Moon after midnight. The radiant is inside the head of the Lion from debris left by Comet 55P/ Temple-Tuttle. We normally see a few stray meteors at every BSC star party even when no meteor shower is expected.

Comets:

The magnitude 7.7 Comet C/2009 P1 Garradd is in the southern section of constellation Hercules so might be viewed this Saturday evening. The comet is now heading north and if it brightens as expected, it will become visible to the naked eye in early 2012. It is now 195 million miles from Earth and can be found 15 degrees west of the Summer Triangle Altair/Vega side, about 8 degrees directly north of the brightest Ophiuchus alpha star “Rasalhague”. The 2011 November issue of Sky & Telescope Magazine shows the path this comet is following on page 52.

A few other comets like C/2010 X1 Elenin and C/2010 G2 Hill are so dim that I won’t go into their details.

Brightest visible asteroids:

Minor Planet 4 Vesta (Mag 7.7), the 2^nd most massive object in the asteroid belt, can be found along the eastern bottom of constellation Capricornus. Vesta has a diameter of about 330 miles and was discovered in 1807. It is about 208 million miles from Earth at this time and has an orbit period of 3.63 years. It should become visible shortly after sunset so might be seen at the BSC star party up to 11:30 pm. NASA’s Dawn spacecraft has just gone into orbit around this asteroid and will study it for a year getting as close as 110 miles from its surface.

Minor Planet 15 Eunomia (Mag 8.1) is close enough to Earth this month that it is the 2^nd brightest asteroid we can see. It is passing through Perseus, sliding along the Hero’s feet and will brighten to magnitude 7.9 by month end. It is about 116 million miles from Earth at this time and has an orbit period of 4.30 years. It should become visible shortly after sunset so might be seen at the BSC star party all the way up to midnight. It is found between Auriga and Perseus, about 5 degrees northeast of  Epsilon Perseus. During this month’s final days, it will pass through the California Nebula (NGC 1499).

Minor Planet 1 Ceres (Mag 8.2) is the biggest object in the asteroid belt with a diameter of about 590 miles. It is in constellation Aquarius and can be found between the Whale’s head and Aquarius. Ceres is about 226 million miles from Earth and has a period of 4.60 years. It was discovered in 1801 and for 50 years was classified as the 8^th planet. It will be visible Saturday evening after the sun sets up to midnight so might be seen at the BSC star party. This asteroid will be the next stop for the Dawn spacecraft.

Deep Sky:

This month let’s consider looking at the only two Messier objects in Hercules and one very faint galaxy:

M13 (Mag 5.8) is the famous Great Hercules Cluster observed by Halley in 1714 and first reported by messier in 1779. It is a globular cluster 21,000 light years away, contains about 500,000 stars and has a diameter of 104 light years. To locate this object, look about 1/3 way down the north-west keystone side from the most northern right side corner star. This is one of the biggest and brightest globular clusters in the sky. A nearby very faint galaxy NGC 6207 is about one degree northeast of M13.

NGC 6207 (Mag 11.2) is a very faint galaxy near M13 but is 1200 times further away. It is about 30 million light years away and if it also has globular clusters, they would be something like a magnitude 22. To find NGC 6207, locate M13 and then move your scope north and east and look for an elongated smudge of light. This will probably require at least a 6″ scope under dark skies.

M92 (Mag 6.4) is another globular Cluster observed by messier in 1781. It is a globular cluster 26,000 light years away, contains a mass of 330,000 Suns and has a diameter of 85 light years. To locate this object, look about 1/3 way down the north-west keystone side from the most northern right side corner star. This is another bright globular cluster that usually takes a back seat to M13 as it is smaller and not as bright, but its core is brighter.