BSC – Saturday 26th March 2011

Hello Fellow OCA club members!

This Saturday, if not cloudy or raining, I will open the gate about: 6:30 pm, which is about a half hour before the sun sets. The weather report for this Saturday indicates that Orange County will be cloudy with even a slight chance of rain. So keep an eye on the OCA website where I will post a notice on the home page should the star party be cancelled.

If we do have a star party, the 3rd quarter moon will not rise until after midnight so we will have fairly dark skies. 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 Irvine Nature Conservancy property rule)

Satellites:

The ISS (International Space Station) and the HST (Hubble Space Telescope) will not make any visible evening passes this week, including Saturday. They both will be making visible morning passes.  There will be two visible Iridium flares Saturday evening, the first at 9:08:43 pm 13 degrees high N (4 degrees) going from a Mag -1 to -6 from Iridium Satellite 20.  The second pass will be less than a minute later at 9:09:08 pm also 13 degrees high N (3 degrees) from Satellite Iridium 23 with a Mag -6.  I am sure we will also see a few dim satellites pass over as we are looking up in the sky.

Planets:

~Mercury, (Mag -0.0) sets about 8:35 pm well after the sun sets so can be seen this Saturday evening low in the western horizon. This planet attained greatest elongation, 19 degrees from the sun on March 22^nd and it was 7.5″ wide and 43% lit. It is about 83 million miles from Earth in constellation Pisces.

~Venus, (Mag -3.9) will not be seen Saturday evening as it sets about 4 pm but can be seen in the morning as it rises about 5:15 am in constellation Capricornus. It will be very bright and about 50 percent illuminated. It is now about 112 million miles from Earth.

 ~Mars, (Mag 1.2) is still in Constellation Aquarius setting about 6:16 pm and rises at 6:30 am so is lost in the sun’s glare this month.  It is about 219 million miles away, still too far away to see any detail on the planet anyway.

~Jupiter, (Mag -1.9) will set about 7:53 pm and is still bright enough that it will become visible in constellation Pisces as the sun sets. It now is about 551 million miles from Earth getting a little further every day. We might still see some detail on the big planet early in the evening including the North Equatorial Belt (NEB) and just a thin dark SEB line, since that belt disappeared in 2010. This Saturday, moon Europa will be seen just west of Jupiter followed by Callisto and Ganymede farthest away.  Io will be just East of the big planet,

~Saturn, (Mag 0.4) rises about 8 pm Saturday in constellation Virgo so will be visible at the BSC star party. Saturn is about 803 million miles away slowly moving closer to Earth. The ringed planet will not set until 7:40 am so can also be seen in the morning sky this month. The rings are narrowing slightly to 9 degrees from edge on so are still spectacular. It will be seen about 10 degrees above Spica this month.

~ Uranus, (Mag 5.9) will set at around 7 pm this week, about sunset, in constellation Pisces so will be lost in the glare of the Sun. When seen, it shows up as a small  blue-green disc in a telescope and is about 1.961 billion miles away, moving further from Earth.

~ Neptune, (Mag 8.0) is in constellation Aquarius, about 2.869 billion miles away this week slowly moving closer to Earth. It is seen as a bluish 2.2″ disc in a telescope but we will not be able to see it at BSC this Saturday evening as it sets about 4:30 pm.

Meteors/Comets/Asteroids:

March is a slow month for meteors with no major showers. We normally see a few stray meteors at every BSC star party even when no meteor shower is expected.

Comets: There are no visible comets brighter than magnitude 12 right now.

Brightest visible evening asteroids:

Minor Planet 20 Massalia (Mag 9.3) can be found in constellation Leo midway along a line between Regulus and Spica. Massalia has a diameter of about 90 miles and was discovered in 1852. It is about 119 million miles from Earth and has a period of 3.74 years.

Minor Planet 3 Juno (Mag 9.4) is another big object in the asteroid belt with a diameter of about 170 miles. It is also in constellation Leo and Juno can also be found half way along a line between Regulus and Spica. Juno is about 166 million miles from Earth and has a period of 4.36 years. It was discovered in 1804.

Minor Planet 7 Iris (Mag 9.4) is the 4th brightest object in the asteroid belt with a diameter of about 125 miles. It is in constellation Gemini and can be found this month about half way along an arc from Pollux to Procyon. Iris is about 159 million miles from Earth, getting farther and has a period of 3.68 years. It was J.R. Hind’s first asteroid discovery made on August 13, 1847.

Deep Sky:

This month let’s go galaxy hunting (M81 & M82 can be seen together in a low powered eyepiece in some scopes):

M81 (Mag 6.8) is a spiral galaxy found near the ear of Ursa Major. It is about 9.5 million light years away and has a diameter of about 72,000 light years. We view this galaxy about face on and it can be found along a line between bowl stars Phad and Dubhe extended about the same distance as Phad is from Dubhe. Johann Bode first discovered this object in 1774 from Berlin and Messier observed it in 1781.

M82 (Mag 8.4) is an irregular galaxy found near the ear of Ursa Major. It is about 9.5 million light years away and spans about 30,000 light years. We view this galaxy edge on, so looks like a cigar, and it can be found along a line between bowl stars Phad and Dubhe extended about the same distance as Phad is from Dubhe. Johann Bode first discovered this object in 1774 from Berlin and Messier observed it in 1781.

M104 (Mag 8.3) is a spiral galaxy found in Virgo near Corvus the Crow. It is about 48 million light years away and has a diameter of about 126,000 light years. We view this galaxy edge and it looks like a sombrero because it has a very dark dust lane and a big middle bulge. Mechain first discovered this object in 1781 described to Bernoulli in a 1783 letter and Messier observed it in 1784.

Don’t forget to bring your gloves, coats & sweaters because it will get even colder 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. Hope to see you there.

Your OCA star party host,

Steve