Saturday January 24th Black Star Canyon star party

Posted On January 20, 2015

Black Star Canyon Star Party notice - Saturday January 24th, 2015

Hello Fellow OCA club members!

This Saturday, I plan to open the gate around 4:45 pm, which is about a half hour before the sun sets. The weather report for this Saturday indicates that Orange County should be windy, have clear skies and humidity near 20%.  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 dark skies as the New Moon occurs January 20th. 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.

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 X-37B (Air Force Boeing space plane) will not make any visible passes as it has landed.

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

  Iridium flares: There will be no visible Iridium Flares this Saturday evening but I am sure we will see a number of satellites pass over in the early evening.

Planets & Pluto:

~Mercury, (Mag 1.8) sets about 6 pm in constellation Aquarius this Saturday so must be seen early at the BSC star party. The small planet seen in a telescope will be just 9"(arc-seconds) across and ¼ lit. Mercury will be about 68 million miles from Earth and does not rise until about 7:30 am.

~Venus, (Mag -3.8) must be seen early Saturday evening as it sets just before 7 pm in constellation Capricornus. Venus will be about 143 million miles from Earth with a disc size of 11" and 92% lit.

~Mars, (Mag 1.2) will be in Constellation Aquarius about 20 degrees high an hour after sunset so might be seen at BSC this Saturday evening in the southwestern sky. It will be about 193 million miles away with a disk size of about 5" (but don't expect to see any detail). Mars sets about 8 pm so better view it early.

~Jupiter, (Mag -2.3) will not rise until 6:15 pm Saturday in constellation Leo so can be seen Saturday evening. It will be about 407 million miles from Earth getting a little closer every day with a diameter of about 45". It can be seen all night as does not set until 7:45 am. At 6:30 pm we should see moon Ganymede far to the East of Jupiter while moons Callisto & Europa will be grouped together a couple of planet widths to the West. Moon Io will be behind Jupiter and will re-appear on the East in 3 hours.

~Saturn, (Mag 1.2) will be in constellation Scorpius this Saturday so will not be seen Saturday evening as it sets about 1 pm. It has a disk measuring 16" with rings spanning 36" and tilting 25 degrees. Saturn will be about 966 million miles away Saturday. It does rise at 2:30 am so can be seen before sunrise.

 ~ Uranus, (Mag 5.9) will be in constellation Pisces this Saturday evening rising about 1 pm so we should see it at the BSC star party when it gets dark. It shows up as a small 3.5" blue-green disc in a telescope so look for it when it gets dark. Uranus will be about 1.893 billion miles from Earth this Saturday and will not set until 10:30 pm.

~ Neptune, (Mag 8.0) is in constellation Aquarius, about 2.865 billion miles away this week slowly moving farther from Earth. It is seen as a bluish gray 2.3" disc in a telescope and we might be able to see it at BSC this Saturday evening as it rises 8:30 am and does not set until 7:30 pm.

 ~ Pluto, (Mag 14.2) sets about 3:30 pm in constellation Sagittarius so will not be seen Saturday evening. It is about 3.137 billion miles from Earth, rises about 5:30 am and is so dim, you would need a 10" or larger telescope to see it visually.


The Quadrantid meteor shower was active from December 28 - January 12 peaking on January 3rd. You could expect to see up to 120 meteors per hour at its peak in dark skies. But we always see a few stray meteors during every 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 again this month except for the one everybody is talking about, Comet Lovejoy.

Comet C/2014 Q2 Lovejoy is a magnitude 4.0 (according to the Heavens-Above website) and will be 53 million miles from Earth Saturday in constellation Aries. It can be seen about 15 degrees North-East of Pleiades. The path it is taking in January is shown on page 42 of the January Astronomy Magazine.

This comet was discovered on August 17th, 2014 by amateur astronomer Terry Lovejoy from Brisbane, Australia, his 5th discovery. It looks to have a period of 14,234 years.

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 brightest asteroid this month again is Minor Planet 4 Vesta (Mag 7.7), the 2nd most massive object in the asteroid belt. It can be found in constellation Sagittarius this month along the Ecliptic between Sagittarius & Capricornus. Vesta has a diameter of about 330 miles and was discovered in 1807. It is about 295 million miles from Earth at this time and has an orbit period of 3.63 years. It will not be visible Saturday evening as is too close to the Sun. NASA's Dawn spacecraft was in orbit around this asteroid and sent back stunning close-up pictures.

Minor Planet 3 Juno (Mag 8.2) is another big object in the asteroid belt with a diameter of about 170 miles. It is in constellation Hydra below the Ecliptic about 20 degrees west of Procyon. Juno is about 124 million miles from Earth now and has a period of 4.36 years. It was discovered September 1, 1804 by German astronomer Karl Harding. But don't expect to see anything more than a small dot. It will be visible Saturday evening and the path it is taking is shown in the January Astronomy Magazine on page 43.

Minor Planet 1 Ceres (Mag 9.1) is the biggest object in the asteroid belt with a diameter of about 590 miles. It is in constellation Sagittarius along the Ecliptic just above the Teapot "Lid". It is about 342 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 not be visible Saturday evening as is too close to the Sun. This asteroid will be the next stop for the Dawn spacecraft in 2015.

Deep Sky:

This month let's consider looking at some neat multiple star systems:

y Andromedae is an attractive double star consisting of a bright orange star with a mag 5 blue companion. All that is needed is a 3" or larger scope to split these stars that are separated by 9.8" (arc-seconds). The stars called Almach AB are the third star in the first Andromeda strand starting from Alpheratz. This double is 355 light years from Earth and the stars are 1,065 AU distance apart with a rotation period of 61.1 years. The secondary is itself a double, both blue in color and separated by just .4". The stars are each 1,179, 56 & 27 times brighter than our sun.

y Arietis is a pair of magnitude 4.8 bluish-white stars that appear to form a true system separated by 7.8", although the relative motion of the stars is very small. Very little change has been noted in the last 350 years. The stars are 36 times brighter than our sun. There is a third component of this set of stars that is not gravitationally bound to the AB components. It is much fainter at magnitude 9.6 and is separated by 221". This star system is found just a few degrees west of Aries Beta star.

n Cassiopeiae is a gorgeous double star consisting of contrasting colors. The colors are most often seen as gold and purple or yellow and red. The primary star is magnitude 3.4 while the secondary is a magnitude 7.5 M class dwarf. The two stars orbit each other every 480 years. The stars are just 19 light years from Earth and are 76 AU distance apart. This double star is found about half way between alpha star Shedir and the Gamma star in Cassiopeia. These stars form the inside of the big "V".

I have given you the double star separations in arc seconds (") but you can use an astrometric eyepiece to check the separation distance yourself. These eyepieces have a laser etched reticle with a ruler graduated at 100 micron intervals that can be used to measure distance. They have a battery powered variable illuminated system so the ruler scale can be easily seen.

Before an accurate measurement can be made, you must calibrate the linear scale to determine the number of arc seconds per division. This is done by using a stop watch to time how long it takes for a star to pass from one end of the scale to the other. To convert to arc-seconds, multiply the time by 15.0411 Cos Y, where Y = the star's declination. Then divide by the number of divisions in the scale.


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.