Saturday 08/31/2013 Black Star Canyon star party

Posted On August 26, 2013

Black Star Canyon Star Party notice - Saturday August 31st, 2013


Hello Fellow OCA club members!

This Saturday, I plan to open the gate around 7 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 make one magnitude 3.0 visible pass this Saturday evening starting at 8:03:54 pm 10 degrees high WSW going to16 degrees high SSW at 8:06:31 and then dropping back to 10 degrees SSE at 8:09:08.

  Iridium flares: There will be no visible Iridium Flares this Saturday evening according to the Heavens-Above website.


Planets & Pluto:

~Mercury, (Mag -1.7) sets about 6 pm in constellation Leo so won't be seen at the BSC star party. Mercury will be about 127 million miles from Earth Saturday but won't be visible until dawn when it rises about 6 am.

~Venus, (Mag -3.9) should be seen Saturday evening before it sets about 8:20 pm in constellation Virgo. Venus is now about 109 million miles from Earth, is approaching 15" in diameter and is near 75% lit.

~Mars, (Mag 1.8) 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 3:45 am, It is about 216 million miles away right now.

~Jupiter, (Mag -1.8) will set about 2:40 pm Saturday in constellation Gemini so won't be seen in the evening. It now is about 535 million miles from Earth getting a little further every day with a diameter of about 34". It does rise about 2:40 am so can be seen before dawn.

~Saturn, (Mag 1.1) will be in constellation Virgo this Saturday so can be seen Saturday evening just after sunset. This planet is about 953 million miles away slowly moving closer to Earth. Saturn sets about 10 pm so should be viewed early. It has a disk measuring 17" and the rings are tilted 17 degrees while spanning 38". Some of the brightest moons should be visible at dusk starting from the east will be 10th magnitude Enceladus and just to the west of Saturn will be Tethys. Below Tethys will be Dione and just below will be Rhea. Far to the west will be 8th magnitude Titan.

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

 ~ Uranus, (Mag 5.8) will be in constellation Pisces this Saturday evening not rising until just about 8:30 pm. It shows up as a small 3.6" blue-green disc in a telescope so look for it Saturday evening. Uranus can be seen all night long setting about 8:30 am and is about 1.790 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 2.695 billion miles away this week slowly moving closer to Earth. It is seen as a bluish gray 2.3" disc in a telescope. We should be able to see it at BSC this Saturday evening as it gets dark because it rises about 6 pm.

 ~ Pluto, (Mag 14.1) rises at 2:20 pm so could be seen Saturday evening through a very large scope. It is 2.965 billion miles from Earth in constellation Sagittarius. Since it is so dim, you will need a 10" or larger telescope to see it visually.



The Perseid meteor shower ran from July 17 - August 24 and peaked August 12th. At its peak, one might see 100 meteors per hour coming from Perseus with the radiant between Polaris and Pleiades. 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.

Brightest visible asteroids:

The brightest asteroid this month is Minor Planet 7 Iris (Mag 8.1) 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 109 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. There is a chart in the August "Astronomy" magazine on page 51 showing the path Iris is on through the month of August.


Deep Sky:

This month let's consider looking at some objects in Sagittarius just above the "Teapot" lid:

M22 (NGC 6656) magnitude 5.1 Globular cluster called the Sagittarius Cluster. It is 10,000 light years away with a diameter of 70 light years. M22 is estimated to have about 70,000 stars and is the 4th largest Globular in the sky, much bigger than M13. It was discovered in 1665 by German Abraham Ihle. It is found just a few degrees east of the top of the "Teapot" lid.

M28 (NGC 6626) is magnitude 6.8 Globular cluster just a degree above the center of the "Teapot" lid. It is 19,000 light years away and has a diameter of 62 light years. It is a very compact set of stars tighter than most clusters. Messier logged this object after observing it July 29, 1764.

M8 (NGC 6523) is a magnitude 6 Emission nebula called the Lagoon Nebula. It is 4,800 light years away and has a physical size of 126 X 56 light years. It is fluorescence due to a 6th magnitude star that stimulates atoms producing light like a neon sign. It is found west from the top of the "Teapot" lid. Messier logged this object after observing it May 23, 1764.

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,