Saturday April 26th Black Star Canyon star party
By: Steve & Bonnie Short
April 23, 2014 4:59AM PDT
Views: 1975


Black Star Canyon Star Party notice - Saturday April 26th, 2014


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 should be partly cloudy with a chance of rain.  So 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 visible magnitude -3.1 pass this Saturday evening starting at 7:58:07 pm 10 degrees high NW going up to 74 degrees high SW at 8:01:27 and then dropping back to 10 degrees high SE at 8:04:45.

  The X-37B (Air Force Boeing space plane) will make one visible magnitude 4.8 pass this Saturday evening starting at 8:22:40 pm 10 degrees high NW going up to 16 degrees high N at 8:24:45 and then dropping back to 10 degrees high NNE at 8:26:51. It is an unmanned plane on a secret mission and will have been in space for 501 days on Saturday.

  The HST (Hubble Space Telescope) will make one visible magnitude 3.1 pass this Saturday evening starting at 8:36:13 pm 10 degrees high SW going up to 13 degrees high SSW at 8:38:10 and then dropping back to 10 degrees high S at 8:40:04.

  Iridium flares: There will be one magnitude -0.6 visible Iridium Flare this Saturday evening nearly due north (352 degrees), 30 degrees high near Polaris at 8:17:07 pm from Iridium satellite 18.

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


Planets & Pluto:

~Mercury, (Mag -1.7) sets at 7:30 pm in constellation Aries this Saturday so won't be seen at the BSC star party. Mercury will be about 125 million miles from Earth and cannot be seen even in the morning when it rises about 6:15 am as it passes behind the Sun.

~Venus, (Mag -4.0) will not be seen Saturday evening as it sets about 4 pm in constellation Aquarius. Venus will be about 90 million miles from Earth, dropping to about a 16” in diameter but will be 65% lit. Venus rises about 4:15 am so can be seen before sunrise.

~Mars, (Mag -1.2) is now in Constellation Virgo rising about 5:30 pm so can be seen at BSC this Saturday evening. It is now about 60 million miles away and doesn't set until 5:15 am. So we can keep looking for the white northern ice cap and other detail now that Mars is close to Earth once again, after 2 years, with a disk size about 15”.

~Jupiter, (Mag -1.8) will rise about 10:30 am Saturday in constellation Gemini so can be seen high in the sky this Saturday evening until it sets just before 1 am. It will be about 515 million miles from Earth getting a little further every day with a diameter of about 35”. At 8:30 pm, we should see moon Callisto far east of Jupiter with Ganymede east of Jupiter by 5 planet widths and then Io half way closer to the big planet. To the west of Jupiter we will see moon Europa a few planet widths away.

~Saturn, (Mag 0.8) will be in constellation Libra this Saturday so can be seen Saturday evening when it rises about 8:30 pm. It has a disk measuring 18” with rings spanning 42” and tilting 22 degrees. Saturn can be seen all night after it rises (as does not set until 7 am). It will be about 835 million miles away Saturday. When Saturn becomes visible around 8:30 pm, we should be able to see some of it's brightest moons starting with brightest moon Titan far to the west. About a planet's width to the west will be moon Tethys with Dione just below. Enceladus will be just east of Saturn barely above the rings while Rhea will be much farther to the east.

 ~ Uranus, (Mag 5.9) will be in constellation Pisces this Saturday evening setting at 5:30 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 after 5 am. Uranus will be about 1.950 billion miles from Earth this Saturday.

~ Neptune, (Mag 7.9) is in constellation Aquarius, about 2.835 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 sets just before 3 pm. It could be seen in the early morning before sunset as it rises about 3:30 am.

 ~ Pluto, (Mag 14.1) sets about 10:30 am in constellation Sagittarius so can't be seen Saturday evening. Since it rises a half hour after midnight, it could be seen until sunrise It is about 3 billion miles from Earth and since it is so dim, you would need a 10” or larger telescope to see it visually.


The Lyrid meteor shower is active from April 16-25 where one might see 18 meteors per hour at it's peak. So we will be one day late but we usually see a few stray meteors during every Saturday evening BSC star party.

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, the brightest C/2012 X1 Linear is a magnitude 12.5 in Aquarius according to the website, Heavens-above.

Astronomy Magazine shows the path comet Panstarrs C/2012 K1 is following this month and claims that a 3” scope under a country sky should be able to see this 9th magnitude object in Bootes. But Heavens-above shows this comet with a magnitude 14.1 so doubt that we can see this object. It will be closing in (about 2 degrees away) on the end handle star (Alkaid) of the Big Dipper Saturday evening.

Brightest visible asteroids:

Finding an asteroid at the BSC star party this month will be very challenging as they are dim and not well positioned for early evening observing. The February Sky & Telescope Magazine, on pages 50-51 shows the circular paths that Vesta and Ceres will be taking in 2014 through July 2nd. Note that they will be only about 3 1/2 degrees apart Saturday evening and only a few degrees from Mars. But on July 1st, these asteroids will be less than ˝ 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 5.9), the 2nd most massive object in the asteroid belt. It can be found in constellation Virgo this month 10 degrees above and east of bright star Spica. Vesta has a diameter of about 330 miles and was discovered in 1807. It is about 116 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 7.1) 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 ahead of Vesta about half way from Spica to Arcturus. It is about 155 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 8.2), 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 due west from Leo's brightest star Regulus and is about 155 million miles from Earth. This asteroid has a diameter of about 338 miles. 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, lets consider looking at some galaxies in Virgo near M49 just behind Leo the Lion:

M49 is a magnitude 8.4 elliptical galaxy and one of the many Virgo Cluster Galaxies. It spans at least 147,000 light years and is 56,000,000 light years from Earth. Not easy to find but it is 8 degrees west of Virgo star Vindemiatrix by itself between two bright 6th magnitude stars that are about 1.5 degrees apart. Messier observed this object in 1779 and compared its brightness to a comet he was watching. But he first observed it in 1771 and logged it on February 19th.

NGC4526 is a magnitude 9.7 lenticular galaxy that is seen nearly edge-on. It is one of the brightest lenticular galaxies, which is defined as an intermediate galaxy between an elliptical and a spiral galaxy. It is 55,000,000 light years away and has a massive black hole in it's center. It was the first to have that mass estimated by an astronomical interferometer measuring the rotation of gas molecules around its center. It's mass is thought to be 450,000,000 times our Sun. You can find NGC4526 about one degree to the left of M49 and slightly lower, with two stars on either side.

NGC4535 is a magnitude 10.0 barred spiral galaxy that is seen 43 degrees face-on. It is 53,000,000 light years away and has two major spiral arms. In 1999, the Hubble telescope was used to observe Cepheid variable stars in this galaxy and the period-luminosity relationship confirmed its estimated distance, which is consistent with other Virgo cluster galaxies. You can find NGC4535 just a half degree above NGC4526.


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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