BSC – Saturday 08 May 2010
Hello Fellow OCA club members!

This Saturday I plan to open the gate about 7:15 pm, nearly a half hour before the sun sets. The weather report for this Saturday indicates that Orange County will be sunny after morning low clouds with afternoon humidity at 45%.  The 3rd Quarter Moon will not rise until well after midnight 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.
Satellites:
The ISS (International Space Station) will not make any visible evening passes this Saturday nor will the HST (Hubble Space Telescope).  But there will be one visible Iridium flare this Saturday at BSC from Iridium satellite 10 at 8:54:29 pm 93 degrees East at 55 degrees altitude flaring from Mag -5 to Mag -8. I am sure we will also see a few other dim satellites pass over as we are looking up in the sky.

Planets:
~Mercury, (Mag 0.2) sets about 6:45 pm so will not be seen this Saturday evening. It is only about 53 million miles from Earth in constellation Aries. Mercury can be seen late this month early in the morning but will only be 5 degrees above the horizon at best.
~Venus, (Mag -3.8) will be the brightest object in the sky after the sun sets and can be spotted 20 degree high in the West in constellation Taurus. It will not set until about 10 pm and is now about 134 million miles from our planet. Venus will be close to full phase (about 88% lit) and will have an 11″ diameter disk.
~Mars, (Mag 0.8) is now in Constellation Cancer,  traveling eastward getting further from Earth, about 124 million miles away. Mars sets about 2 am so will be seen high in the sky this Saturday evening at BSC. A 12″ or larger scope will be needed to see any detail, like the white polar cap.

~Jupiter, (Mag -2.0) rises about 3:45 am in constellation Pisces so the big planet can be seen this month  only late in the early morning. Jupiter sets around 3:30 pm so is lost in the sun’s glow and cannot be seen in the evening. It now is about 518 million miles from Earth and getting a little closer every day.

~Saturn, (Mag 0.8) rises about 3:45 pm Saturday in constellation Virgo so will  be visible just before sunset at BSC Saturday evening.  It sets in the East at 4 am so can no longer be seen in the morning.  Saturn is about 818 million miles away moving further from Earth. The rings tilt only about 2 degrees to our line of sight but they will open again this summer and tilt 10% by year end. Saturday evening only moon Enceladus will be to the east of Saturn while moons Tethys, Dione, Titan and Rhea will be on the west in that order.

~ Uranus, (Mag 5.9) will rise about 4 am in constellation Pisces this week and be just 4 degrees from Jupiter so both planets can be seen in the same binocular view. But we will not see this planet at BSC Saturday as we close at midnight. When we can see this planet, it shows up as a blue-green disc in a telescope. It is about 1.933 billion miles away moving closer to Earth.

~ Neptune, (Mag 7.9) is in constellation Aquarius, about 2.813 billion miles away this week slowly moving closer to Earth. Neptune is now less than 1 degree from where it was discovered September 13, 1846 by Johann Galle.  It is seen as a bluish disc in a telescope but we will not see it this Saturday as it sets about 1:30 pm. Neptune can be seen in the late morning sky as it rises at 2:30 am.

 Meteors/Comets/Asteroids:

The Eta Aquarid meteor shower peaks before dawn on May 6th where you might see up to 20 meteors per hour in a dark sky. The  radiant is in Aquarius about 20 degrees from the 3^rd quarter moon and the meteors comes from particles left by comet 1P/Halley.

Comet C/2009 K5 McNaught (Mag 9.7) is in constellation Cepheus and is about 128 million miles from Earth. It can be found high in the sky and is heading towards Polaris. It was discovered by Rob McNaught May 27^th, 2009 in Australia.

Comet 81P Wild 2 (Mag 10.0) is in constellation Virgo just 5 degree west of NGC 5634 and about 7 degrees above the Ecliptic. It’s orbit lies close to the plane of our solar system so we see this comet edge-on. That causes us to see the dust tail as a sharp streak rather than the typical fan tail. This comet is now about 70 million miles from earth and has a period of 6.42 years. Samples of this comet were returned to earth and contained an amino acid, one of life’s fundamental building blocks.

Comet C/2007 Q3 Siding Spring (Mag 11.9) is now about 270 million miles away from Earth in constellation Draco. On Saturday, it will be about 12 degrees directly below the Little Dipper. This comet was discovered August 25^th, 2007 (thus the designation C/2007) by D. M. Burton from the Siding Spring Survey.

 
Minor Planet 4 Vesta (Mag 7.4) is the 2^nd 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 inside the Lion’s head, right in the middle. It is now is about 179 million miles from Earth and has a period of 3.63 years.

Minor Planet 1 Ceres (Mag 7.9) can be found in constellation Sagittarius directly above the “Teapot” lid.. It is about 191 million miles from Earth and has a period of 4.60 years.

Minor Planet 2 Pallas (Mag 8.6) can be found in constellation Serpens 15 degrees due east of Arcturs, just under the Corona Borealis. It is about 183 million miles from Earth and has a period of 4.62 years.

Minor planet 532 Herculina (Mag 9.6) is in constellation Leo just 12 degrees (almost) directly north of Leo the Lion’s tail star (Denebola). It is only about 150 million miles from Earth with a period of 4.61 years. It was discovered in 1904 by Max Wolf and is about 138 miles in diameter. This was the first asteroid to have a confirmed asteroid moon – about 45 km orbiting at a distance of about 1,000 km.

Deep Sky:
This month, lets go galaxy hunting (the topic at the April 5^th Go-To SIG meeting) around Virgo:

M98 (Mag 10.1) is a spiral galaxy about 56 million light years away with a diameter of 163,000 light years which we see nearly edge-on. It is found near 6 Comae Berenices.  Messier observed this object in 1781 but had no idea what it was.

M99  (Mag 9.8) is a spiral galaxy about 56 million light years away with a diameter of  81,000 light years which we see face-on. It is also found near 6 Comae Berenices.  Messier also observed this object in 1781.
M100 (Mag 9.4) is another spiral galaxy about 41 million light years away with a diamater of 83,000 light years which we see face-on. It is found in the same binocular view as M98 & M99 and is near cigar shaped galaxy NGC 4312. Messier found this object in early 1781.

 Don’t forget to bring your gloves, coats & sweaters because it may get very cold as the sun sets and 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.
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Your OCA star party host,

Steve