Hello Fellow OCA club members!
I plan to open the gate about 7 pm this Saturday, a half hour before the sun sets, at 7:28 pm. Looks like we will have a clear night for a change. 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. 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 drivers window to light up the road directly in front of your car.
Comet 46P/Wirtanen (Mag 12) has now faded such that it is out of range for most 6" scopes as it is passing through Gemini on it's 5.4 year orbit around the sun. Then there is Comet 17P/Holmes (Mag 6.5) now in the southern part of Auriga, and over 352 million miles from Earth. While looking around that area, we might spot the 595 mile wide asteroid Ceres (Mag 8.9), just east of the Pleiades star cluster (M45) and below star Aldebaran in constellation Tarus the Bull. We might also want to try and locate the the 120 mile wide asteroid Hebe (Mag 10.6) as it glides through constellation Cancer, moving at about a quarter of a degree each night.
No visible HST (Hubble Space Telescope) or ISS (International Space Station) passes will take place this Saturday evening. But we will get to see a very bright Iridium flare at 8:30:56 PM ESE (106 degrees) at 58 degrees altitude starting off at a Mag -1 and flaring to -8 from satellite Iridium 18.
Mercury (Mag -1.6) in Aries will be setting shortly after the sun goes down so will be hard to spot. Mars (Mag 1.0) keeps getting further from Earth, now over 144 million miles away and traveling diagonally under the Gemini Twins. By month end it will be lined up with Pollux & Castor just 5 degrees from Pollux, so for awhile the Gemini Twins will be Triplets. Saturn (Mag 0.4) will be up all Saturday evening just under the body of Leo the Lion and is now about 815 million miles from Earth. Saturn has a family of over 60 moons with a handful that glow bright enough for us to see in small amateur telescopes. This Saturday, Titan (Mag 8.3) will be passing in front of Saturn from the east with Tethys (Mag 10.2) on the west side of the planet. All the visible moons of Saturn will be very close to the planet include Dione (Mag 10.4), Enceledas (Mag 11.7) and Rhea (Mag 9.7). The other planets, Jupiter (Mag -2.0), Venus (Mag -3.8), Uranus (Mag 5.9), Neptune (Mag 8.0) and dwarf planet Pluto (Mag 14) can only be seen just before or at dawn.
Since Saturn is roaming around Leo the Lion, lets consider looking for some galaxies up in that area just under the tail of the Lion. Just below 3rd magnitude star Chertan lies the M66 group of galaxies consisting of M65, M66 & NGC 3628, all within 1 degree and sometimes called the “Leo Triplet”. They can all be seen along with star Chertan in a 5 degree finder scope view.
M65 (Mag 9.3) is a spiral galaxy 29 million light years from Earth that is 84,000 light years in diameter, so is a little smaller than the 100,000 mile wide Milky Way Galaxy where we live. We see this galaxy almost edge on and when seen at around 50X power, M65 is perpendicular to bottom of Leo the lion.
M66 (Mag 9.0) is another spiral galaxy, about 25 million light years from Earth and is about 65,000 light years in diameter. This galaxy we see more face on so it may look a little brighter than M65. Both M65 & M66 were observed by Messier in 1780 and catalogued as nebulae. He saw them as cloudy objects but had no idea they were galaxies.
The final Leo Triplet is NGC 3628 (Mag 9.5) which is 32 million light years from Earth and has a plume that seems to stretch 400,000 light years to the east. We see this galaxy edge on and it is parallel to the bottom of Leo the Lion.
Don't forget to bring your gloves, coats & sweaters just because it was warmer this week as it will get cold as the night gets later. After you set up your telescope, there are three picnic tables where you can sit and eat food you might bring, while waiting for it 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,