Alamogordo Astronomy A News Letter for Astronomy in Southern New Mexico

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1 Alamogordo Astronomy News Letter The April Issue Volume 1, Issue 3 Published 31 Mar 12 On The Internet Amateur Astronomers Group Tonight s Sky Hubble Images omy/tonights_sky Visible Planet Guide earthsky.org The Sky This Month - nighskyinfo Sky Watching Events - space.com US NAVAL Observatory ronomical-applications Produced By P.O. Box 4151 Alamogordo, NM aacwp@zianet.com Alamogordo Astronomy A News Letter for Astronomy in Southern New Mexico What Happened In March Coronal Mass Ejections The sun released very powerful coronal mass ejections (CMEs) around March 7, causing rapid changes to the shape of Earth's magnetosphere and resulting in increased geomagnetic storms. Extreme UV flash of X5-class solar flare March 7, (NASA SDO) Read the NASA article about Space Weather on Pg 3 and Solar Activity, by Jim Tomaka, on Pg 4. Astronomy Club Meeting The club finalized the plans for the Messier Marathon with overnight camping at White Sands National Monument, April 21. We also began the planning for a White Sands Star Party in September. Mr. James Fox provided an excellent presentation on Variable Star Observation. Buena Vista Star Party The Buena Vista Star Party (BVSP) for March was a great night for observing, including the Moon, Jupiter, Venus and the Orion Nebula. The star party lasted about two hours. April Upcoming Activities Buena Vista Star Party The upcoming BVSP is on the moonless evening of 14 April. This star party will include Venus, Jupiter, Mars, and maybe Saturn. Beginning around sunset (7:34); duration depends on Weather, Visibility, and Participation. Oliver Lee Memorial State Park Night Sky Program Mars in Leo Join the Amateur Astronomers Group (AAG) for a tour of the stars and constellations in the dark skies over Oliver Lee Memorial State Park. Although Mars made its closest approach in March, this is still a good time to view it. As Saturn rises in the east, a few Lyrid meteors may light up the sky. April 21, 8:00 PM to 9:30 PM Messier Marathon, 2012 All area astronomy clubs are invited to an overnight Messier Marathon at White Sands National Monument on April 21, Please contact Mr. Chris Jones, fooie@tulatosa.net, if you would like to attend. The only fee is the White Sands National Monument. park fees: entrance fee $3.00 per person 18 years & older; camping fees $3.00 per adult, $1.50 for anyone 17 years old and younger. Be sure to tell the gate attendant that you intend to camp. ALAMOGORDO ASTRONOMY 1

2 Buena Vista Corner In Our Own Back Yard This month s Buena Vista Corner is an article from UniverseToday.com about the Cave telescope. Local area astronomer Jim Tomaka provided some wonderful pictures and his explanations. The Cave Astrola In the late 1960s early 70s, the Cave Astrola telescope was on everyone s dream list. Here was everything we d ever envisioned a true astronomical telescope to be. Great optics, fancy mount and gasp! Portability. Up until that time, Newtonian telescopes of any size were simply locked into Observatories because of mount required permanent installation. This made the Cave Astrola hugely popular and Cave Optical produced about 83,000 mirrors and 16,000 complete telescopes with mountings sold under the Astrola brand name before it was sold in Messier Moment This Hubble telescope image of the Trifid Nebula reveals a stellar nursery being torn apart by radiation from a nearby, massive star. The picture also provides a peek at embryonic stars forming within an ill-fated cloud of dust and gas, which is destined to be eaten away by the glare from the massive neighbor. This stellar activity is a beautiful example of how the life cycles of stars like our Sun are intimately connected with their more powerful siblings. ALAMOGORDO ASTRONOMY Comet Garrard passed by Messier 92 on its outward trek from the inner solar system on February 3, Its orbit never takes it closer to the Sun than Mars at its closest approach to the Sun in December 2011 it was still 1.55 astronomical units from the Sun. Garrard would be a great comet if had passed closer to the Sun! The photograph was taken using a stock Canon T2i DSLR through a Borg 71FL astrograph telescope. This photo was taken by my 5 yr old daughter Emily. Her favorite nebula is the Horsehead (B33) in Orion. She wanted to take pictures of nebulas, so she came out to the observatory, worked the computer to slew the telescope and set the camera to take a series of exposures. The image was taken through Emily's Stellarvue SV80ED that she won at NEAF 2011 and Dad's modified Canon XS Rebel DSLR. 2

3 Interesting Information SPRITE SEASON BEGINS: The first sprites of summer are starting to appear in the skies of North America. The strange thing is, summer is almost three months away. "Sprite season is beginning early this year," says Thomas Ashcraft, who photographed these specimens on March 30th from his observatory in New Mexico: Space Weather Storms From the Sun Space weather starts at the sun. It begins with an eruption such as a huge burst of light and radiation called a solar flare or a gigantic cloud of solar material called a coronal mass ejection (CME). But the effects of those eruptions happen at Earth, or at least near-earth space. Scientists monitor several kinds of space "weather" events, all caused by these immense explosions on the sun. Geomagnetic Storms "At precisely two minutes and twenty-six seconds after midnight March 30, 2012 there was an incredibly powerful bolt of lightning in the vicinity of Woodward, Oklahoma that spawned these red sprites," says Ashcraft. "I could see them from two states away!" Sprites are electrical discharges that come out of the top of thunderclouds, opposite ordinary lightning bolts which plunge toward Earth. Sprites can tower as high as 90 km above ground. That makes them a form of space weather as they overlap the zone of auroras, meteors, and noctilucent clouds. Because they are associated with lightning, sprites are most often seen in summer months, "but in the past few days sprites have been reported in Texas (particularly near the Mexican border) as well as here in New Mexico," notes Ashcraft. So if there's lightning where you live, be alert for sprites. One of the most common forms of space weather, a geomagnetic storm refers to any time Earth's magnetic environment, the magnetosphere, undergoes sudden and repeated change. When geomagnetic storms are caused by CMEs, the solar material in a CME travels with its own set of magnetic fields. If the fields point northward, they align with the magnetosphere's own fields and the energy and particles simply slide around Earth, causing little change. But if the magnetic fields point southward, in the opposite direction of Earth's fields, the effects can be dramatic. The sun's magnetic fields peel back the outermost layers of Earth's fields changing the whole shape of the magnetosphere. This is the initial phase of a geomagnetic storm. The next phase, the main phase, can last hours to days, as charged particles sweeping into the magnetosphere accumulate more energy and more speed. These particles penetrate closer and closer to the planet. During this phase viewers on Earth may see bright aurora at lower latitudes than usual. The increase and lower altitude of radiation can also damage satellites traveling around Earth. The final stage of a geomagnetic storm lasts a few days as the magnetosphere returns to its original state. In the most extreme cases transformers in power grids may be damaged, spacecraft operation and satellite tracking can be hindered, high frequency radio propagation and satellite navigation systems can be blocked, and auroras may appear much further south than normal. ALAMOGORDO ASTRONOMY 3

4 Solar Activity on the Increase - - By Jim Tomaka The Sun has been in a deep slumber since late 2006, but it now appears solar cycle 24 is in full swing. However, it s behaving oddly; the Gaussian fits aren t working so well. We re currently looking at a maximum probably around May of 2013, which for an 11-year cycle is right around the corner. Solar maximum is that point when the Sun s magnetic field is its most tangled, when you have field lines that are poking through the surface, and when you see sunspots. The sunspots often come in pairs, and one of them is the point where the field line is coming through the surface, and other one is the point where the field line is going back into the surface. These field lines get twisted around and channels plasma, and these footprints can be connecting plasma loops. They can be the cause of giant coronal mass ejections. Amateur astronomers in southern New Mexico have taken notice and have been documenting this solar cycle. With the wide array of equipment now available to the amateur, comparison images are now possible. The photograph below shows a White Light image (left) and the same image through a Calcium K-line filter (393.4 nm) (right). (Image provided by the AAG) Imaging at the Calcium K (CaK) wavelength highlights areas of increased magnetic activity. A CaK telescope will image calcium atoms in the lower chromosphere about 2000km above the solar surface or photosphere. A more popular wavelength to view the sun is at the Hydrogen alpha (Hα) emission line (656.3 nm). The Hα line is generated when the recombined electrons in the hydrogen atom jump from the 2nd to 3rd, or the 3rd to 2nd, energy level. This occurs about 3500km above the photosphere. Below is an image taken at Ha through a Lunt 80mm Ha pressure-tuned solar telescope (active region 1429 was undergoing an M-class solar flare at the time). As the altitude above the photosphere increases, so does the temperature (which is somewhat counterintuitive). The NASA/ESA SOHO satellite images the Sun at 304 nm (ionized Helium, approximately 50,000 K) and the Solar Dynamics Observatory (SDO) images at even high wavelengths through X-ray. Each of these images provides insight to the processes occurring. Near realtime images can be seen on the AAG website at ALAMOGORDO ASTRONOMY 4

5 Selected Sky Watching Information for April From the Space Telescope Science Institute, Hubblesite, web site Evening Planets In early April, four planets grace the sky at nightfall. In the west, Jupiter hangs low on the horizon. Around mid-month, the planet disappears into the sunset. Venus blazes just above Jupiter in the west. Use a telescope to see its crescent phase. In the south, Mars is already climbing high. It will remain visible into the early morning. Saturn will shine low in the east in the evening but climb higher during the night. On April 15th, Saturn reaches opposition, meaning it is opposite the Sun in Earth s sky. It is also closer to Earth than it ll be the rest of the year, making it appear slightly bigger and brighter. Constellations and Deep-Sky Objects Late in the evening, high in the northern sky lies the Great Bear, Ursa Major. The constellation of Ursa Major contains the well-known star pattern, the Big Dipper. It resembles a large drinking cup with a handle. The two stars that make up the front side of the cup are called pointer stars because they point toward the star Polaris, also known as the North Star. The Big Dipper overflows with interesting stars and deep-sky objects. The stars Mizar and Alcor make up a double-star system that can be seen without a telescope. In ancient times, when Mizar and Alcor were even closer together, they were used as a test of keen eyesight. M81 and M82 are a magnificent pair of galaxies, showpieces of the northern night sky. M82 has an irregular shape, bestowed by a collision with its larger neighbor, M81. Turning to the south, we see Leo, the Lion, heralding the coming of spring. In Greek mythology, Leo is the great beast slain by Hercules. The star Denebola, which in Arabic means tail, represents exactly that. The bright star Regulus is the heart of the Lion. Leo has several galaxies in his belly. M65, M66, and NGC 3628 make up the Leo Triplet, a lovely grouping of galaxies easily seen with a telescope. Close by is another group. M95 and M96 are large spiral galaxies. Between the Big Dipper and the head of Leo are three pairs of bright stars known to ancient Arab astronomers as The Three Leaps of the Gazelle. Events The Lyrid meteor shower will be best seen in the early morning hours of April 22nd. Under a dark sky, you can expect to see up to 20 bright meteors per hour. Southern New Mexico Public Events for April Living Desert Star Party At Living Desert Zoo State Park near Carlsbad, 20 April. The club meets on the third Friday of the Month at 7:30 PM (except in December) at the Gerald Champion Medical Center- Conference Rooms 1 and 2 in Alamogordo, New Mexico. Visit us on facebook Or on the web at ALAMOGORDO ASTRONOMY 5