Saturday June 21st Black Star Canyon star party

Posted On June 18, 2014


Black Star Canyon Star Party notice - Saturday June 21st, 2014

Hello Fellow OCA club members!

This Saturday, I plan to 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 should be partly cloudy with mild temperatures and 40% humidity.  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.

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


Try to park two cars in each slanted slot between the rock turning circles so we can get 20 cars into that area. I will help guide the first cars into the slots and then expect that others will follow that pattern. The first car in each slot must stay back, about a foot, from the road that leads out of the parking area so cars that leave early with headlights off will not accidentally bump into parked cars.

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


  The ISS (International Space Station) will make one magnitude -3.2 visible pass Saturday evening starting at 9:51:05 pm 10 degrees high NW going to 62 degrees high SW at 9:54:21 then dropping to 59 degrees high SSW at 9:54:36 right between the Big Dipper and Leo the Lion ending between Bootes and Virgo.

  The X-37B (Air Force Boeing space plane) will make one magnitude 3.4 visible passes this Saturday evening starting at 9:22:35 pm 10 degrees high NW going to 28 degrees high NNE at 9:25:06 and then dropping to 18 degrees ENE at 9:26:32 going between Cassiopeia and the Little Dipper ending in Cygnus the Swan going right through middle wing star Sadr.

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

  Iridium flares: There will be one magnitude 0.9 visible Iridium Flare this Saturday evening ENE (72 degrees), 40 degrees high at 9:46:45 pm from Iridium satellite 97 seen between Cygnus and Hercules.

I am sure we will also see a number of satellites pass over in the early evening.

Planets & Pluto:

~Mercury, (Mag 4.4) sets about 7:30 pm in constellation Taurus this Saturday so probably won't be seen at the BSC star party. Mercury will be about 52 million miles from Earth.

~Venus, (Mag -3.8) will not be seen Saturday evening as it sets about 5:30 pm in constellation Taurus. Venus rises about 3:45 am so can be seen a few hours before sunrise. Venus will be about 125 million miles from Earth, dropping to about a 12" in diameter but will be 84% lit.

~Mars, (Mag -0.1) is now in Constellation Virgo rising about 2 pm so can be seen at BSC this Saturday evening. It is now about 87 million miles away with a disk size of about 10 degrees and doesn't set until 1:30 am. So this is our last chance to get a final glimpse of the white northern ice cap and other detail before Mars gets too far away.

~Jupiter, (Mag -1.6) will rise about 7:30 am Saturday in constellation Gemini so can be seen high in the sky this Saturday evening until it sets about 9:30 pm. It will be about 575 million miles from Earth getting a little further every day with a diameter of about 32". The giant planet will pass just 6.5 degrees south of Pollux Saturday night. At 8:30 pm, we should see moon IO just east of Jupiter with Ganymede even closer. West of Jupiter will be Europa and much farther west will be Callisto.

~Saturn, (Mag 0.9) will be in constellation Libra this Saturday so can be seen Saturday evening as it rises about 4:30 pm. It has a disk measuring 18" with rings spanning 42" and tilting 21 degrees. Saturn can be seen most all night after it rises (as does not set until 3:15 am). It will be about 850 million miles away Saturday. When Saturn becomes visible around 9 pm, we should be able to see some of it's brightest moons starting with brightest moon Titan far east of Saturn with Dione about a planet's width to the east. Moon Enceladus will be behind Saturn while Tethys will be west of the planet with Rhea twice as far west.

 ~ Uranus, (Mag 5.9) will be in constellation Pisces this Saturday evening setting about 2 pm so we will not see it at the BSC star party. It shows up as a small 3.5" blue-green disc in a telescope so look for it early Saturday morning after it rises just about 1:30 am. Uranus will be about 1.885 billion miles from Earth this Saturday.

~ Neptune, (Mag 7.9) is in constellation Aquarius, about 2.750 billion miles away this week slowly moving closer to Earth. It is seen as a bluish gray 2.3" disc in a telescope but we won't be able to see it at BSC this Saturday evening as it does not rise until midnight when we close.

 ~ Pluto, (Mag 14.1) rises about 8:40 pm in constellation Sagittarius so might be seen Saturday evening. Since it does not set until 6:45 am, it could be seen until sunrise It is about 2.950 billion miles from Earth and since it is so dim, you would need a 10" or larger telescope to see it visually.



There are no major meteor showers in June.


If you ever wanted to do some real scientific meteor counting, the International Meteor Organization (IMO) always needs more observers. You will need to follow the IMO's standards so your counts will be meaningful. See for more information.


Brightest visible Comets:

All the comets in the sky are very dim this month with the brightest, C/2014 E2 Jacques, a magnitude 9.1 in Orion according to the website, Heavens-above.


Page 42 of the June Astronomy Magazine shows the path comet Panstarrs C/2012 K1 is following early this month and predicts that it will be above the sickle shape of Leo's head Saturday. But Heavens-above shows this comet with a magnitude 11.0 so it will be difficult to find this object at the star party. It will be about 177 million miles from Earth.


Brightest visible asteroids:

Finding an asteroid at the BSC star party is always very challenging as they are dim and are just small dots. The June Astronomy Magazine, on page 43 shows the paths that Vesta and Ceres will be taking in June. Note that they will be less than 1 degree apart Saturday evening in constellation Virgo. But on July 1st, these asteroids will be less than ¬Ω degree apart. The circular paths are between Spica and Arcturus, closer to Spica than Arcturus.


The brightest asteroid this month is Minor Planet 4 Vesta (Mag 6.9), the 2nd most massive object in the asteroid belt. It can be found in constellation Virgo this month forming an isosceles triangle with Mars and bright star Spica. Vesta has a diameter of about 330 miles and was discovered in 1807. It is about 153 million miles from Earth at this time and has an orbit period of 3.63 years. It should be visible at the BSC star party at sunset. NASA's Dawn spacecraft was in orbit around this asteroid and sent back stunning close-up pictures.

Minor Planet 1 Ceres (Mag 8.2) is the biggest object in the asteroid belt with a diameter of about 590 miles. It is in constellation Virgo and can be found just 3 degrees ahead of Vesta and 10 degrees directly above Spica. It is about 202 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. But don't expect to see anything more than a small dot. It will be visible Saturday evening at sunset so might be seen at the BSC star party. This asteroid will be the next stop for the Dawn spacecraft.


Minor Planet 2 Pallas (Mag 9.2), is the second asteroid to have been discovered (after Ceres), and one of the largest in the Solar System. It can be found in constellation Leo this month about 10 degrees east from Leo's brightest star Regulus, just before the tail. This asteroid has a diameter of about 338 miles and is about 235 million miles from Earth. When Pallas was discovered by astronomer Heinrich Wilhelm Matthaus Olbers on March 28, 1802, it was counted as a planet, as were other asteroids in the early 19th century. The discovery of many more asteroids after 1845 eventually led to their re-classification. It is about 130 million miles from Earth at this time and has an orbit period of 4.62 years. It will become visible at sunset so might be seen at the BSC star party.



Deep Sky:

This month let's consider looking at some globular clusters in the Scorpion:

M4 is a magnitude 3.1 globular star cluster, known as the "Cat's Eye" as it looks like a bit like the eye of a cat. It is in constellation Scorpius, is about 14,000 light years away and spans 107 light years. You can find it about one degree west of bright star Antares. Its age is estimated to be 10 billion years old and has a looser compactness than average. Messier observed this object in 1764 and logged it on May 8th.

M80 is a magnitude 7.3 globular star cluster in constellation Scorpius. It is about 33,000 light years away and spans 86 light years. You can find it just above and about half way between bright stars Antares and the center star of the Scorpion's 3 star head. This is a very tight cluster of well over 100,000 stars. Messier observed this object in 1781 and logged it on January 4th.

NGC 6144 is a 10th magnitude globular star cluster in constellation Scorpius, about 33,000 light years away and spans 24 light years. It is a very large cluster of small stars in a very tight cluster. You can find it just north of bright star Antares and its brighter famous neighbor, M4. William Herschel discovered this object in 1785 with an 18.7-inch F/13 scope. .



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.