Fort Worth Astronomical Society (Est. 1949) April 2010 : Astronomical League Member Club Calendar – 2 Skyportunities – 3 Club Reports – 5 Peculiar Galaxies – 6 Ben’s Best 100 Minor Planets – 8 Spectacular Spiral! – 9 Matt’s Media Reviews – 10 Stargazers’ Diary – 11 Witch Head Nebula by Paul Hunsberger 1 April 2010 Sunday Monday Tuesday Wednesday Thursday Friday Saturday 2 3 Fort Worth First photograph of Astronomical Society Sun taken 165 years ago Top ten deep-sky objects for April: M65, M66, M95, M96, M97, M105, M108, NGC 3115, NGC 3242, NGC 3628 Top ten binocular deep-sky objects for April: M65, M66, M95, M96, M97, M105, M108, M109, NGC 3115, NGC 3242 4 5 6 7 8 9 10 Algol at Minima First commercial Third Qtr Moon Earth Day mission to Mir 4:37 am Irving Event 2:10 am 10 years ago. BSA Star Party Algol at Minima Bridgeport 5:21 am Zefram Cochran Moon at Apogee invented warp drive Vesta Stationary 10 pm 53 years from now. in Leo (251,657 miles) 11 12 13 14 15 16 17 Algol at Minima New Moon 7:29 am 10:59 pm 3RF Star Party Project Ozma started 50 years ago Apollo 13 launched 40 years ago Viking 2 lander Expedition 11 crew Income Tax First test firing of Apollo 13 crew launched to ISS returns to Earth mission ended 30 Due Saturn V first stage years ago Yuri’s Night 15 years ago 45 years ago 40 years ago 18 19 20 21 22 23 24 Algol at Minima Algol at Minima 3RF Lunar Party 1:59 am 10:48 pm Museum Star Party First Qtr Moon FWAS Meeting 1:20 pm Moon at Perigee Shapley-Curtis 3 pm (228131 miles) Debate on nature & distance of spiral April Lyrid nebulae Meteors Astronomy Day 90 years ago. (Spring) 25 26 27 28 29 30 31 Full Moon 7:18 am Jan Oort b. 110 years ago. Challenge deep-sky object for April: Leo I (Leo) Challenge binary star for April: Gamma Sextantis Notable variable star for April: S Ursae Majoris (Ursa Major) Notable carbon star for April: V Hydrae (Hydra) 2 The Sky This Month – Thomsen Foundation -- 9 pm local time, April 15 (from Heavens-Above.com) Star Charts: Sky & Telescope Sky Maps http://tinyrul.com/5np8n http://www.skymaps.com Heavens Above International Space Station Transits http://www.heavens-above.com http://tinyrul.com/y8zk5c Planets, Meteors, and Comets! Oh My! Mercury: Evening Star the first half of April. Venus: Evening Star this month. Use Venus as your guide for finding Mercury about after sunset for the first week and a half of April. Venus & Mercury will be 3O apart on Easter weekend. A crescent Moon is 4O N on the 16th. Mars: In the evening sky, but is shrinking like a leaky balloon as its eastern motion increases through the month. Mars will be near the Beehive from the 15th to the 18th. Jupiter: A low Morning Star in Aquarius. Saturn: Excellently placed in the night sky, as it was at opposition late last month. He is in retrograde motion this month. Uranus: Reappearing into the dawn sky; but is a challenging target for observers here. Neptune: In the eastern morning sky this month, but it is very challenging target for observers here. Pluto: Forgetaboutit. The April Lyrid Meteor shower is considered a minor shower with a ZHR of about 10. They span from the16th - 26th, with a max of less than a day as the Earth passes through the debris of Comet Thatcher It is unpredictable, having had remarkable fall rates recorded from 687 BC (“like rain”) to more recent outbursts in 1803, 1922 (100 for one hour), and 1982 (180 to 300 within a few minutes). Lyra rises in the northeast at about 10 p.m., but the best time to view is the hours before dawn after the waxing gibbous moon has set. 3 Observing and Outreach Opportunities Weather permitting (FWAS contacts in parentheses) April 10 - Purtis Creek State Park - Stargazing & Take a Walk Through the Solar System - Take a walk through the solar system and view the night sky through a telescope. Then make your own star wheel and learn how to use it. Meet at the overflow camping parking lot. Accessible for the mobility impaired. 7:30 p.m. (903) 425-2332. April 17 (DSO) & 24 (Lunar) - Three Rivers Foundation (“3RF”) - 3RF invites you out to Comanche Springs near Crowell, Texas for a night under the stars. The dark skies of Big Ranch Country provide a spectacular view of the universe. The party starts with solar observing followed by a break. Evening activities begin with a short educational introduction to astronomy. The observatories and Star Field are then opened to the public to enjoy the use of many different kinds of astronomy instruments. For more information the day of a scheduled star party, please call 940-655-3384. (Russ Boatright and Doug Brown) (Panhandle Plains, where Oklahoma tucks into the Texas Panhandle) April 17 - Tyler State Park - Star Party - See the first star come out and make your wish! Bring your telescopes or binoculars, flashlight with red lens, drinks, lawn chairs and insect repellent. We will have campfire stories if it's cloudy. Accessible for the mobility impaired. 8-10 p.m. (903) 597-5338. April 17 - Goose Island State Park - Goose Island Under the Stars - Join us in the evening when volunteers from the Corpus Christi Astronomical Society will lead a tour of the night skies. Learn about the constellations and see the moon, planets, stars and galaxies through the telescope. Bring your lawn chairs and your binoculars and meets us at the Recreation Hall for an informative and fun night. Accessible for the mobility impaired. 8:30-9:30 (361) 729-2858. April 24 – FWAS & Noble Planetarium Star Party – Come one; come all to the star party at the Fort Worth Museum of Science and History. These star parties provide a great opportunity to bring your children and give them a chance to look though a number of different telescopes. And for new members it is a good time to see a number of different telescopes and talk to other club members about them. And of course, we need members with telescopes and binoculars that enjoy sharing the sky with Museum guests. We meet in the parking lot to the south of the museum on the corner of Montgomery and Harley. Time: dusk (sunset is about 7:40 so give yourself some time to set up) until 10:30. Michele will bring brownies and Linda will provide drinks. (Linda Krouse & Michele Martinez) Lunation 1080 at Age: Philolaus Crater 10 Days, 12 hours *and everyone knows that the Moon is made out of green cheese.” Plato Crater The picture to the left almost shows what the Sinus Iridum Moon will look like at 7:29 pm on the night of “Bay of Rainbows” our April 24th 2010 Museum star party. Mare Imbrium This image does not exactly represent what will be visible along the limbs, because on that night the libration of the Moon will be centered almost due lunar North. The Montes Carpatus Moon’s North Pole will appear to be tilted Copernicus Crater more towards us. The northern limb will be most exposed by 6.6O on the 26th. At Lansburg Crater Moonrise, the Moon’s SW will be “down.” Let’s look at a few of the terminator targets. Sinus Iridum was formed after Mare Imbrium, Note that the object that formed this crater came in at such an angle that the Bullialdus Crater southeast rim is below the later lava flow. By inference, the impacting object’s approach must have come well within the lunar orbit. Also, look at Bullialdus Crater and compare its topography to the larger Copernicus Crater which is also well illuminated this night. Take note of Bulliadus’ crisp lines as the crater rim terraces down to the interior flood plain and central peak; comparing these sharp features with the many challenging older ghost craters that surround Bulliadus. This image was borrowed from http://www.stargazing.net/David/moon/day10h12moonfull.html 4 Star Party Reports Ridglea Hills ES Star Party: The "Mobile Noble' was pleased to participate in Science Night at Ridglea Hills Elementary School. Approximately 135 people attended our 5 planetarium shows. We spent about 25 minutes with each group, pointing out stars, constellation outlines and constellation figures, as well as the visible planets. Because it was cloudy when we first got there (although it cleared later), activities were somewhat limited for the people who came, so we also took them on a tour through our solar system. Students and parents alike learned how to 'redden' their flashlights with red balloons, how to dark adapt their eyes, and to make use of binoculars if they had them. Everyone seemed to have a great time, and the science teacher told us to save a place on our calendars for next year, so I guess it was a successful night." – Linda Krouse Dinosaur Valley Star Party: The weather was decent and it was a full house for the park’s March stargazing shindig. Dr. Ray Benge of Tarrant County Community College gave a dusk show and tell before the crowd took to the scopes; and we easily had 150 or more folks attend. A great time was had by all! The next scheduled event there is May 8th. – Scott MacDonald and Juan Martinez Museum & FWAS Star Party: There was a full array of scopes in anticipation of a full house crowd of guests at the March Museum Star Party.