Saturday 07/13/2013 Black Star Canyon star party
By: Steve & Bonnie Short
July 10, 2013 3:16AM PDT
Views: 2732


Black Star Canyon Star Party notice - Saturday July 13th, 2013


Hello Fellow OCA club members!


This Saturday, our guest host (Don Stoutenger) will open the gate around 7:30 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 we had a new Moon Monday. 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 2.8 visible pass this Saturday evening starting at 8:34:26 pm 10 degrees high WSW going to17 degrees high SSW at 8:37:15 and then dropping back to 10 degrees SSE at 8:40:03.

  Iridium flares: We should be able to see 2 Saturday evening at BSC and I am sure we will also see a number of dim satellites pass overhead as we are looking up in the sky. The first flare from Iridium satellite 90 will be a bright magnitude -5.6 occurring at 9:23:03 11 degrees high NNW (346 degrees). The second flare from Iridium 66 will be a magnitude -2.1 occurring at 10:50:17 13 degrees high NE (49 degrees).


Planets & Pluto:

~Mercury, (Mag 4.9) sets about 7:40 pm in constellation Gemini so won't be seen at the BSC star party. Mercury will be about 53 million miles from Earth Saturday but won't be visible until dawn the last week in July.

~Venus, (Mag -3.8) should be seen Saturday evening before it sets about 9:40 pm in constellation Gemini. Venus is now about 136 million miles from Earth, is approaching 12” in diameter and is near 87% lit.

~Mars, (Mag 1.8) is now in Constellation Taurus setting about 6:30 pm, so is too close to the Suns glare to be seen in the evening. Mars might be seen just before dawn as it rises about 4:20 am, It is about 228 million miles away right now.

~Jupiter, (Mag -1.7) will set about 7 pm Saturday in constellation Gemini so won't be seen in the evening. It now is about 568 million miles from Earth getting a little further every day with a diameter of about 33”. It does rise about 4:45 am so can be seen just before dawn.

~Saturn, (Mag 1.0) will be in constellation Virgo this Saturday so can be seen Saturday evening just after sunset. This planet is about 883 million miles away slowly moving closer to Earth. Saturn doesn’t set until 1:25 am so is visible most of the night with a disk measuring 17” and the rings are tilted 17 degrees while spanning 39”. Some of the brightest moons should be visible starting off with 8th magnitude Titan. From the west will be 10th magnitude Rhea, then Dione, Enceladus, Mimas near Saturn with Tethys below the planet.

 ~ Uranus, (Mag 5.8) will be in constellation Pisces this Saturday evening not rising until just after midnight. It shows up as a small 3.6” blue-green disc in a telescope but we won’t be able to see it Saturday evening. Uranus is now a morning object rising at 00:15 am. It is about 1.854 billion miles from Earth.

~ Neptune, (Mag 7.8) is in constellation Aquarius, about 2.725 billion miles away this week slowly moving closer to Earth. It is seen as a bluish gray 2.3” disc in a telescope. We might be able to see it at BSC this Saturday evening after it rises about 10:30 pm.

 ~ Pluto, (Mag 14.0) rises at 7:15 pm so could be seen Saturday evening through a very large scope. It is 2.926 billion miles from Earth in constellation Sagittarius. Since it is so dim, you will need a 10” or larger telescope to see it visually when it does rise.


The Southern Delta Aquarid meteor shower runs from July 12 – August 13 but peaks July 30th. At its peak, one might see 10 meteors per hour coming from Aquarius with the radiant about 10 degrees above star Formalhaut. We usually see a few stray meteors during every Saturday evening BSC star party.

Brightest visible Comets:

This month Comet C/2011 L4 (PANSTARRS) is a dim magnitude 13.0 as it passes through constellation Draco. The path it is following in July is shown in the 2013 July “Astronomy” magazine on page 42. It will be 231 million miles from Earth Saturday evening.

Brightest visible asteroids:

Bright asteroids Ceres and Vesta have wandered through Taurus the Bull and are now in Gemini this month so can be seen Saturday evening.


Minor Planet 4 Vesta (Mag 8.2), the 2nd most massive object in the asteroid belt, can be found in constellation Cancer this month., between Venus and the Sun. Vesta has a diameter of about 330 miles and was discovered in 1807. It is about 321 million miles from Earth at this time and has an orbit period of 3.63 years. It will become visible shortly after sunset so might be seen at the BSC star party. NASA’s Dawn spacecraft was in orbit around this asteroid and sent back stunning close-up pictures.


Minor Planet 1 Ceres (Mag 8.7) is the biggest object in the asteroid belt with a diameter of about 590 miles. It is in constellation Cancer and can be found just a few degrees above Vesta. The June 2013 “Astronomy” magazine showed the path Ceres was following during the month of June on page 43. It is about 325 million miles from Earth now and has a period of 4.61 years. It was discovered in 1801 and for 50 years was classified as the 8th planet. It will be visible Saturday evening shortly after sunset so might be seen at the BSC star party. But don’t expect to see anything more than a small dot. This asteroid will be the next stop for the Dawn spacecraft.


Deep Sky:

This month let’s consider looking at some objects in the Summer Triangle:


Albireo is a wide spaced double star 430 light years away. It is found by locating Cygnus the Swan and is the star that represents the Swan's head. The brighter magnitude 3.1 amber star and the blue-green magnitude 5.1 companion have an orbital period of at least 100,000 years if they are physically attached by gravity. Most people see the brighter star as yellow and the dimmer star as blue and many think this is one of the prettiest binary stars in the sky.



Epsilon Lyrae is a multiple star system with the outer two stars easily split by low telescope power or even with binoculars. They are about 162 light years away and have magnitudes of 5.1 and 4.7. When viewed at higher magnification, these two stars each show they are binary stars too with just a 2.35 arc-second separation so they are a good test for a telescope's optics. One of the secondary binary stars has an orbit of about 1200 years which means they are 140 AU apart. The other binary pair is about half that distance. This star formation can be found just a few degrees from Vega in a line heading towards Deneb, the tail of the Swan.

M57 (catalogued by Messier in 1779) is a planetary nebula commonly called the Ring Nebula as it looks like a smoke ring. It is in the northern constellation of Lyra the Harp. This object was formed when a giant red star blew off it's gasses as it became a white dwarf. It is found 40% of the distance from Beta to Gamma Lyrae and will probably require 100X magnification to see in a small scope. The central star is a faint magnitude 14.8 so is difficult to spot unless using a big telescope. This object is at least 1400 light years away.



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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