Saturday April 14th Black Star Canyon star party
By: Steve & Bonnie Short
April 11, 2012 2:27AM PDT
Views: 3068

BSC Star Party Notice  - Saturday April 14th, 2012


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 get rain Wednesday and again on Friday into Saturday. So 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.


The last quarter Moon will start April 13th so will not rise until after midnight Saturday. 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 (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 see any Iridium flares Saturday evening 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 0.9) sets at 5 pm so cannot be seen this Saturday evening. It is about 70 million miles from Earth in constellation Pisces with maybe a 6” diameter disk. You might spot it 30 minutes before sunrise just 4 degrees above the horizon.

~Venus, (Mag -4.3) should be seen Saturday evening until it sets about 11 pm in constellation Taurus. Venus is now about 55 million miles from Earth, going from 50 % lit this month to 25% swelling from a 25” disk to 37”.

 ~Mars, (Mag -0.5) is still in Constellation Leo rising about 3:30 pm so is visible high in the sky as the sun sets. It is about 75 million miles away now with a 13” disk at April 1st that will shrink to 10” at month end so small scopes might struggle to see some detail on the red planet. The white north polar cap tips towards Earth now and you might see some dusky markings on the planet’s surface under dark skies.

~Jupiter, (Mag -1.8) will set about 9 pm in constellation Aries so should be your first target Saturday evening. It now is about 548 million miles from Earth getting a little farther every day. It has shrunk to a diameter of 34”. We should see moon Callisto far West of the big planet while moon Io will be very close to Jupiter. Moons Europa and Ganymede will be directly between Io & Europa.

~Saturn, (Mag 0.7) will be in constellation Virgo this Saturday but won’t rise until 7:30 pm, just after sunset.  Saturn is about 812 million miles away slowly moving closer to Earth. Saturn’s globe measures 19” across at the equator but only 17” from pole to pole because it is a fast spinning gaseous planet. The rings span 43” and tilt 14 degrees to our line of sight at mid month. That is a healthy tilt so will provide observers with a good look at the dark Cassini Division that separates the two brightest rings. Largest moon Titan will be far east of Saturn with moon Rhea much closer. Moons Dione, Enceladus and Tethys will be just west of Saturn.

~ Uranus, (Mag 5.9) will be in constellation Pisces this Saturday evening and sets about 6 pm so will not be seen at the BSC star party. It shows up as a small 3.4” blue-green disc in a telescope if you want to catch it in the morning about 6 am. It is about 1.956 billion miles away from Earth.

~ Neptune, (Mag 7.9) is in constellation Aquarius, about 2.850 billion miles away this week slowly moving closer to Earth. It is seen as a bluish gray 2.2” disc in a telescope. We will not be able to see it at BSC this Saturday evening, as it sets about 3:20 pm not rising until about 4:30 am.

 ~ Pluto, (Mag 14.1) does not rise until 1 am so cannot be seen Saturday evening.  It is 2.975 billion miles from Earth in constellation Sagittarius slowly getting closer to Earth. Since it is so dim, you will probably need a 10” or larger telescope to see it visually when it rises about 1 am.  The 2011 July issue of Sky & Telescope Magazine shows the path Pluto was following in 2011 on page 64. From that diagram, one can see that Pluto is still found high above the Sagittarius “Teapot”.



The Lyrid meteor shower peaks before dawn April 22nd and with no moon in the sky, viewing conditions should be perfect. The radiant will be near bright star Vega. We normally see a few sporadic meteors at every Black Star Canyon star party.


Brightest visible Comets:

The magnitude 8.5 Comet C/2009 P1 Garradd is in the southern section of constellation Ursa Major headed towards Lynx so can be viewed this Saturday evening at sunset through dawn. The comet is now heading southward and passed just 2 degrees east of magnitude 9.2 galaxy NGC 2841 one week ago. It is now 160 million miles from Earth traveling back into the depths of the solar system. The 2012 April issue of Astronomy Magazine shows the path this comet is following through April on page 42.


Brightest visible asteroids:

Minor Planet 5 Astraea (Mag 9.9) is in constellation Leo this month about 10 degrees below the middle of the Lion’s tail. It is about 119 million miles from Earth at this time and has an orbit period of 4.13 years. It is another potato shaped rock about 75 miles wide. This asteroid was discovered in 1845 by amateur astronomer and postal employee Karl Ludwig Hencke and the King of Prussia awarded him an annual pension of 1,200 marks for the discovery. It should become visible shortly after sunset so might be seen at the BSC star party all the way up to midnight and later.


Minor Planet 6 Hebes (Mag 10.0) has a diameter of about 120 miles, contains ½ percent of the mass of the entire asteroid belt and was the 5th asteroid discovered. It is in constellation Leo and can be found on the back of Leo the Lion all month long. It is about 348 million miles from Earth and has a period of 3.78 years. It was discovered July 1, 1847 by Karl Ludwig Hencke, his 2nd and last asteroid discovery. It will be visible Saturday evening after the sun sets so might be seen at the BSC star party.


Deep Sky:

This month let’s consider looking at some galaxies called the Leo Galaxy Trio:


M65 (Mag 9.3) is a spiral galaxy, 29 million light years from Earth that spans 84,000 light years. It was first observed by Messier in 1780 and he called it a faint nebula with no stars. It is found about 2.5 degrees below the 3rd magnitude star Chertan in Leo.


M66 (Mag 9.0) is another spiral galaxy, 25-39 million light years from Earth that spans 65,000 – 102,000 light years. It was first observed by Messier in 1780 and he called it another faint nebula with no stars right next to M65, in the same telescope field. It is found about 2.5 degrees below the 3rd magnitude star Chertan in Leo.



NGC 3628 (Mag XXX) is the 3rd spiral galaxy, 36 million light years from Earth that has a 300,000 light years long tidal tail. It was discovered by William Herschel in 1784. This galaxy is also found about 2.5 degrees below the 3rd magnitude star Chertan in Leo and completes the famous Leo Triplet.


All three of these galaxies are within a degree of each other so can be seen in a wide angle eyepiece field of view.




Don't forget to bring your gloves, coats & sweaters because it can get very cold after 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 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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