Saturday September 8th Black Star Canyon star party

Posted On September 5, 2012

BSC Star Party Notice  Saturday September 8th, 2012


Hello Fellow OCA club members!


This Saturday, I plan to open the gate around 6:40 pm, which is about a half hour before the sun sets. The weather report for this Saturday indicates that Orange County will again be sunny, hot and very clear.  But keep an eye on the OCA website “Home” page (below the next speaker info) where I will post a notice should the star party be cancelled for any reason, even high fire danger.


We should have dark skies as the last quarter Moon will not rise until after midnight Saturday. First time visitors might want to get to the star party site 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 OC Parks and Nature Conservancy rule).



  The ISS (International Space Station) will not make any visible passes Saturday evening.

  The HST (Hubble Space Telescope) will also not make any visible passes Saturday evening.

  We will not even get to see any Iridium flares Saturday evening at BSC. But I am sure we will see a few dim satellites pass overhead as we are looking up in the sky.


Planets & Pluto:

~Mercury, (Mag -1.4) sets at 7 pm in constellation Leo but is too close to the Sun this month to make a good target for observations.

~Venus, (Mag -4.0) will not be seen Saturday evening as it sets about 4:45 pm in constellation Orion. Venus is now about 81 million miles from Earth and can be seen early morning as it rises at 3 am. On Saturday morning Venus should be 60% lit with a 19″ disk.

 ~Mars, (Mag 1.3) is now in Constellation Libra so is visible at sunset until setting at 9:30 pm. Mars will be just a bit higher in the sky than Saturn, as it sets 20 minutes after Saturn sets. Mars is about 170 million miles away now with a 5″ disk so none of our scopes should be able to see any detail on the red planet.

~Jupiter, (Mag -2.1) will rise about 11:40 pm in constellation Taurus Saturday evening, so will not be up in time for us to observe in a telescope at the star party, as we wil be packing them up. It now is about 462 million miles from Earth getting a little closer every day.

~Saturn, (Mag 1.1) will be in constellation Virgo this Saturday just 5 degrees above bright star Spica, but sets early at about 9 pm. Saturn is about 975 million miles away slowly moving farther from Earth. Saturn’s globe measures 15″ but the rings span 36″ and tilt 14 degrees to our line of sight this month. As it gets dark, largest moon Titan (magnitude 8), which revolves around Saturn every 16 days, will be far east of Saturn. All the moons will form a semicircle around Saturn. Moon Dione will be half way from Titan to Saturn and moon Enceladus will be just under Saturn. Moon Tethys will be just west of Saturn’s rings and moon Rhea will be about twice as far west.

~ Uranus, (Mag 5.7) will be in constellation Cetus this Saturday evening but doesn’t rise until a few minutes after 8 pm. It shows up as a small 3.7″ blue-green disc in a telescope. This planet reaches opposition on September 29th, when it lies opposite the Sun in our sky. It will remain visible from sunset to sunrise and glows bigger and brighter than at any other time of the year. It is about 1.780 billion miles away from Earth which is about as close as it gets to our planet.


     Note: The September Sky & Telescope magazine shows the 2012 paths of Uranus and Neptune on page 50.


~ Neptune, (Mag 7.8) is in constellation Aquarius, about 2.698 billion miles away this week slowly moving closer to Earth. It is seen as a bluish gray 2.4″ disc in a telescope. We should be able to see it at BSC this Saturday evening (it is bright enough to even be seen through binoculars), as it rises about 6:30 pm.

 ~ Pluto, (Mag 14.1) rises about 3:15 pm so could be seen Saturday evening up to about 1:30 am when it sets.  It is 2.965 billion miles from Earth in constellation Sagittarius. Since it is so dim, you will probably need a 10″ or larger telescope to see it visually. The June 2012 Sky & Telescope magazine shows Pluto’s path for all of 2012 on pages 52-53.  On Saturday, Pluto will be just 1.5 degrees west from the center of M25.



The IMO (International Meteor Organization) has identified a relatively new Meteor Shower that is active from September 4-14 and peaks on the 9/10th. The radiant is in Perseus and in 2008 observers saw a flurry of bright meteors. This Saturday we might see about 5 meteors per hour before the Moon rises.


Brightest visible Comets:

This month all the comets orbiting the Sun are very dim so will be extremely difficult to find and see. 


The magnitude 12.5 Comet C/2011 L4 Panstarrs might be seen Saturday at the BSC star party in constellation Hydra (10 degrees in front of the Scorpion’s head). It is about 331 million miles from Earth at this time. This comet was discovered in June 2011 by a team using the Pan-Starrs telescope on Maui and has a very parabolic orbit. It will approach within 30 million miles of the Sun in early 2013, about the distance Mercury is from the Sun.



Brightest visible asteroids:


Bright asteroids Ceres and Vesta are close to Jupiter this month so cannot be seen Saturday evening but can be seen in the early morning.


Minor Planet 2 Pallas (Mag 9.3) is in constellation Cetus this month just 5 degrees  northeast of Uranus and 5 degrees directly above (north) of the Whale’s head. It is about 292 million miles from Earth and has an orbit period of 4.61 years.  This asteroid may be the largest irregular object in the solar system as it is not rounded under its own gravity. It was discovered in 1802 by astronomer Heinrich Olbers.


Minor Planet 11 Parthenope (Mag 9.0) is in constellation Aquarius this month, just 5 degrees below the Ecliptic on a straight line from Pegasus star Scheat through Formalhaut, so could be spotted at the star party. It is about 113 million miles from Earth at this time and has an orbit period of 3.84 years. In January 2011, 20 amateur astronomers timed this asteroid as it blocked the light of a background star. They determined that it is potato shaped about 93 miles across at its longest dimension. This asteroid was discovered by Annibale de Gasparis on May 11, 1850, the second of his nine asteroid discoveries


Deep Sky:

This month let’s consider looking at some Messier Open Cluster objects in constellation Scutum down to Sagittarius” which Messier observed in May & June of 1764:


M11, also known as the “Wild Duck Cluster”, is a magnitude 5.8 open star cluster about 5,600 light years away that is 23 light years at its widest dimension. This cluster contains about 200 stars, the brightest shining at a magnitude 8. Its age is estimated to be 220 million years. You can find it in constellation Scutum just off the tail of Aquila.


M26 is a magnitude 8.0 open star cluster in Scutum about 4,900 light years away that spans 21 light years. It contains about 30 stars, the brightest shining at a magnitude 10. Its age is estimated to be 89 million years. You can also find this star cluster in constellation Scutum, just a few degrees below M11.