Saturday 09/28/2013 Black Star Canyon star party
By: Steve & Bonnie Short
September 24, 2013 3:21AM PDT
Views: 2570


Black Star Canyon Star Party notice - Saturday September 28th, 2013


Hello Fellow OCA club members!


This Saturday, I plan to open the gate around 6:15 pm, which is about a half hour before the sun sets. The weather report for this Saturday indicates that Orange County will be sunny with humidity at 30% and some light winds.  But please keep an eye on the OCA website “Home” page (below the next speaker info) where we will post a notice should the star party be canceled for any reason. With all the heat, there is always concern about fire danger.


We should have fairly dark skies as the 3rd quarter Moon will not rise until after midnight. 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.


WarningNo Pets allowed(This is an OC Parks and Nature Conservancy rule).



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

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

  Iridium flares: There will be no visible Iridium Flares this Saturday evening according to the Heavens-Above website but we always see a number of slow moving satellites cross the night sky.


Planets & Pluto:

~Mercury, (Mag 0.0) sets about 7:30 pm in constellation Virgo so will be hard to see at the BSC star party. Mercury will be about 115 million miles from Earth Saturday but was just .8 degrees from Spica, the closest passage of any planet to a 1st magnitude star during 2013.

~Venus, (Mag -4.2) should be seen Saturday evening before it sets about 8:30 pm in constellation Libra. Venus is now about 90 million miles from Earth, is approaching 18” in diameter and is near 65% lit.

~Mars, (Mag 1.6) is now in Constellation Cancer setting about 3:45 pm, so won't be seen in the evening. Mars might be seen just before dawn as it rises about 3:15 am with a disk almost 4”. It is about 203 million miles away right now.

~Jupiter, (Mag -1.9) will set about 3 pm Saturday in constellation Gemini so won't be seen in the evening. It now is about 500 million miles from Earth getting a little further every day with a diameter of about 38”. It does rise about 1 am so can be seen an hour after midnight until dawn.

~Saturn, (Mag 1.2) will be in constellation Libra this Saturday so can be seen Saturday evening just after sunset. This planet is about 988 million miles away slowly moving closer to Earth. Saturn sets about 8:30 pm so should be viewed early. It has a disk measuring 16” and the rings are tilted 18 degrees while spanning 36”. Some of the brightest moons should be visible at dusk starting with 8th magnitude Titan well below Saturn. Just to the west of the rings will be Dione and Enceladus with Tethys to the right and Rhea further to the right.

-----The August ”Astronomy” magazine page 81 shows the path Uranus is taking through October.---

 ~ Uranus, (Mag 5.7) will be in constellation Pisces this Saturday evening not rising until just about 7:15 pm. It shows up as a small 3.7” blue-green disc in a telescope so look for it Saturday evening. Uranus can be seen all night long setting about 7:30 am and is about 1.772 billion miles from Earth.

-----The August ”Astronomy” magazine page 81 shows the path Neptune is taking through October.---

~ Neptune, (Mag 7.8) is in constellation Aquarius, about 2.705 billion miles away this week slowly moving farther from 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 as it gets dark because it rises about 5:30 pm.

 ~ Pluto, (Mag 14.1) rises at 2:15 pm so could be seen Saturday evening through a very large scope. It is 3.009 billion miles from Earth in constellation Sagittarius. Since it is so dim, you will need a 10” or larger telescope to see it visually.


September is a quiet month for meteors and no major showers occur. The Aurigid meteor shower ran from August 28 – September 5th and peaked September 1st. At its peak, one might see 6 meteors per hour coming from Auriga with the radiant well below bright star Capella. We usually see a few stray meteors during every Saturday evening BSC star party.

Brightest visible Comets:

This month there are no comets bright enough to be seen at Black Star. But everyone is keeping a sharp eye on Comet ISON (C/2012 S1) as it started off just a degree above the Beehive Cluster M44 on the 1st of the month. Saturday it will be just above Mars at a dim magnitude 14 not showing up until about 1am. It is predicted to be the comet of the century as is expected to become very bright in December.

Brightest visible asteroids:

The brightest asteroid this month is Minor Planet 4 Vesta (Mag 8.2) Minor, the 2nd most massive object in the asteroid belt, can be found in constellation Leo this month., between Mars and the Sun. Vesta has a diameter of about 330 miles and was discovered in 1807. It is about 305 million miles from Earth at this time and has an orbit period of 3.63 years. It will not be visible at the BSC star party. NASA’s Dawn spacecraft was in orbit around this asteroid and sent back stunning close-up pictures.


Minor Planet 324 Bamberga (Mag 8.3), is bigger than half the first 10 asteroids discovered and can be found in constellation Pisces this month. This asteroid has a diameter of about 140 miles but was not discovered until 1892 by Austrian astronomer Johann Palisa because it has such a dark surface. This asteroid has a very high orbital eccentricity (0.34) so every 22 years comes closer to Earth than any other asteroid this big. It is about 76 million miles from Earth at this time and has an orbit period of 4.40 years. Better try and view it now as it won't be this close again until 2035. It will become visible shortly after sunset so might be seen at the BSC star party.

Minor Planet 7 Iris (Mag 8.6) in Aquarius, the 4th brightest object in the asteroid belt. Iris has a diameter of about 125 miles and was discovered on August 13, 1847, by J. R. Hind from London. It was Hind's first asteroid discovery and the seventh asteroid to be discovered overall. It is about 117 million miles from Earth at this time and has an orbit period of 3.69 years. It will become visible shortly after sunset so might be seen at the BSC star party.


Deep Sky:

This month let’s consider looking at some objects in Hercules:


The most famous is M13 (NGC 6205), a magnitude 5.8 Globular cluster called the Great Hercules Cluster. It is 21,000 light years away with a diameter of 104 light years with an age estimated to be 14 billion years. M13 is estimated to have about 500,000 stars and is one of the biggest and brightest globulars in the sky. It was discovered in 1714 by Edmond Halley and recorded by Messier in 1764. M13 is found between two corner stars of the Keystone in Hercules, about 1/3 of the way down from the most northern, right sided corner star.


M92 is a magnitude 6.4 Globular cluster found above the Keystone in Hercules. It is 26,000 light years away and has a diameter of 85 light years. It is a very compact set of stars tighter than most clusters. Although this cluster usually takes a back seat to nearby M13, it is a spectacular globular cluster with a brighter core. Messier logged this object after observing it March 18, 1781.


Don't forget to bring your gloves, coats & sweaters as it can get cold after the sun sets and even colder 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 the sky to get dark. Please remember to cart off all your trash as there are no garbage cans at BSC. There is also one portable restroom on site should nature call.


Hope to see you there.


Your OCA star party host,


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