2012 August

AEA Astronomy Club Newsletter, August 2012

Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 2
Astronomy News p. 6
General Calendar p. 7
    Colloquia, lectures, mtgs. p. 7
    Observing p. 8
Useful Links p. 9
About the Club p. 10

Club News & Calendar.

Calendar

Club Meeting Schedule:

16-Aug-12	100-Year Low Earth Debris Population Model	Alan Jenkin (& Marlon Sorge)	Aerospace	A1/2143
20-Sep-12	Star Trackers	Art Okawauchi	Aerospace	A3/1607A/B
18-Oct-12	High/Wide Dynamic Range CMOS Imagers	Blake Jacquot (and Hung Ngo)	Aerospace	A1/1029A/B
15-Nov-12	Upper Atmospheric Disturbances Using RAIDS and Ground-Based Measurements	Rebecca Bishop & Andrew Christensen	Aerospace	A1/1029A/B
19-Dec-12	Beyond Next Generation Access To Space	Scott Martinelli and Jay Penn	Aerospace	A1/1029A/B

AEA Astronomy Club meetings are on 3^rd Thursdays at 11:45am.  For 2012, April-May we meet in A1/1026; June-July & Oct.-Dec. in A1/1029A/B; Aug. in A1/2143 and Sept. in A3/1607A/B.

News:  

A generous benefactor has just donated a new Meade LightBridge 16-inch (0.4m) truss Dobsonian telescope to the club!  We’ve got aperture!  F/4.5, fl 1.8m, limiting mag. 15.5.  $2,000 retail.  Combined with our soon-to-arrive astronomical video camera, it should yield an effective visual aperture of over 1.2m (or >0.75m for the 10-inch)! 

Specs & video (showing a 12-inch version): http://www.telescopes.com/telescopes/dobsonian-telescopes/meadelightbridgedeluxe16inchtrusstubedobsoniantelescope.cfm

One review of the Meade LightBridge 16-Inch Truss - Tube Dobsonian Telescope – Deluxe [at the above website – other reviews have additional excellent suggestions.  See also http://www.cloudynights.com/item.php?item_id=2693]:

“Surprisingly the tube assembly is a bit lighter, though more bulky, than my 10 inch LX200. Recommend for the experienced amateur in order to find things, though the FOV is so large, it's not hard to star hop. For pure scientific power the LX series ACF is far superior, but for sheer joyful visual astronomy with basically zero set up, you can't go wrong with nearly half meter aperture! Get a 2" meade 5000 series super or ultra wide (26 to 34mm ideal) [eyepiece --] the view is worth every cent. The primary fan is a critical feature, thermal soak is an issue with any large primary. The fan brings the mirror to thermal equilibrium quickly, and it's neat to watch before your eyes the thermal induced astigmatism just go away in about 15 min.”

Astronomy Video(s) & Picture(s) of the Month

(from Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html)

Video(s)

Nocturnal: Scenes from the Southern Night http://apod.nasa.gov/apod/ap120806.html
Have you ever seen the night sky change?  The above award winning video shows several of the possible changes in dramatic fashion with a time lapse video. Visible are sunset-illuminated clouds moving, stars of vivid colors rising, the long tail of a Comet Lovejoy rising, bright satellites crossing, a meteor exploding, a distant lightning storm approaching, skyscapes including the Magellanic Clouds rotating, and a fisheye sky rotating while the foreground becomes illuminated by moonlight. Frequently featuring an artistic human sculpture in the foreground and the southern sky in the background, the video closes with a time lapse clip of a total lunar eclipse. If you can identify any more of the sky events depicted -- or any of the landscapes shown -- please illuminate them with a comment.

Lightning Captured at 7,207 Images per Second http://apod.nasa.gov/apod/ap120723.html

Simulation: A Disk Galaxy Forms http://apod.nasa.gov/apod/ap120717.html

Source: Jet Propulsion Laboratory

NASA released an image from the Mars Reconnaissance Orbiter which was taken during the descent of the Mars Science Laboratory with the Curiosity rover and shows the deployed parachute and the spacecraft as it prepares to land.  The image was taken while MRO was 211 miles (340 kilometers) away from the parachuting rover. Curiosity and its rocket-propelled backpack, contained within the conical-shaped back shell, had yet to be deployed. At the time, Curiosity was about two miles (three kilometers) above the Martian surface.

Source: Jet Propulsion Laboratory

About two hours after landing on Mars and beaming back its first image, NASA's Curiosity rover transmitted a higher-resolution image of its new Martian home, Gale Crater. Mission Control at NASA's Jet Propulsion Laboratory in Pasadena, Calif., received the image, taken by one of the vehicle's lower-fidelity, black-and-white Hazard Avoidance Cameras - or Hazcams. Other cameras aboard Curiosity, with color capability and much higher resolution, are expected to be sent back to Earth over the next several days.

"In the image, we are looking to the northwest. What you see on the horizon is the rim of Gale Crater. In the foreground, you can see a gravel field. The question is, where does this gravel come from? It is the first of what will be many scientific questions to come from our new home on Mars."

Curiosity landed at 10:32 p.m. Aug. 5, PDT, (1:32 a.m. EDT, Aug. 6) near the foot of a mountain three miles (about five kilometers) tall inside Gale Crater, 96 miles (nearly 155 kilometers) in diameter. During a nearly two-year prime mission, the rover will investigate whether the region has ever offered conditions favorable for microbial life, including the chemical ingredients for life.

For more information on the mission, visit: http://www.nasa.gov/mars and http://marsprogram.jpl.nasa.gov/msl .

Ash and Lightning Above an Icelandic Volcano
Image Credit & Copyright: Sigurður Stefnisson

Explanation: Why did the picturesque 2010 volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well-populated areas. The Eyjafjallajökull volcano in southern Iceland began erupting on 2010 March 20, with a second eruption starting under the center of a small glacier on 2010 April 14. Neither eruption was unusually powerful. The second eruption, however, melted a large amount of glacial ice which then cooled and fragmented lava into gritty glass particles that were carried up with the rising volcanic plume. Pictured above during the second eruption, lightning bolts illuminate ash pouring out of the Eyjafjallajökull volcano.

Orion Nebula: The Hubble View
Image Credit: NASA, ESA, M. Robberto (STScI/ESA) et al.

Explanation: Few cosmic vistas excite the imagination like the Orion Nebula. Also known as M42, the nebula's glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1,500 light-years away. The Orion Nebula offers one of the best opportunities to study how stars are born partly because it is the nearest large star-forming region, but also because the nebula's energetic stars have blown away obscuring gas and dust clouds that would otherwise block our view - providing an intimate look at a range of ongoing stages of starbirth and evolution. This detailed image of the Orion Nebula is the sharpest ever, constructed using data from the Hubble Space Telescope's Advanced Camera for Surveys and the European Southern Observatory's La Silla 2.2 meter telescope. The mosaic contains a billion pixels at full resolution and reveals about 3,000 stars.

A Hole in Mars
Image Credit: NASA, JPL, U. Arizona

Explanation: What created this unusual hole in Mars? The hole was discovered by chance on images of the dusty slopes of Mars' Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars. The hole appears to be an opening to an underground cavern, partly illuminated on the image right. Analysis of this and follow-up images revealed the opening to be about 35 meters across, while the interior shadow angle indicates that the underlying cavern is roughly 20 meters deep. Why there is a circular crater surrounding this hole remains a topic of speculation, as is the full extent of the underlying cavern. Holes such as this are of particular interest because their interior caves are relatively protected from the harsh surface of Mars, making them relatively good candidates to contain Martian life. These pits are therefore prime targets for possible future spacecraft, robots, and even human interplanetary explorers.

Astronomy News:

(from e! Science News Astronomy & Space)

Fingering the culprit that polluted the Solar System

Published: Thursday, August 2, 2012 - 14:11 in Astronomy & Space

For decades it has been thought that a shock wave from a supernova explosion triggered the formation of our Solar System. According to this theory, the shock wave also injected material from the exploding star into a cloud of dust and gas, and the newly polluted cloud collapsed to form the Sun and its surrounding planets. New work from Carnegie's Alan Boss and Sandra Keiser provides the first fully three-dimensional (3-D) models for how this process could have happened. Their work will be published by The Astrophysical Journal Letters.

Traces of the supernova's pollution can be found in meteorites in the form of short-lived radioactive isotopes, or SLRIs. SLRIs -- versions of elements with the same number of protons, but a different number of neutrons -- found in primitive meteorites decay on time scales of millions of years and turn into different, so-called daughter, elements. A million years may sound like a long time, but it is actually considered short when compared to other radioactive isotopes studied by geochemists and cosmochemists, which have half-lives measured in billions of years.

When scientists find the daughter elements distributed in telltale patterns in primitive meteorites, this means that the parent SLRIs had to be created just before the meteorites themselves were formed. This presents a timing problem, as the SLRIs must be formed in a supernova, injected into the presolar cloud, and trapped inside the meteoritic precursors, all in less than a million years.

The telltale patterns prove that the relevant daughter elements were not the ones that were injected. This is because the abundances of these daughters in different mineral phases in the meteorite are correlated with the abundances of a stable isotope of the parent element. Different elements have different chemical behaviors during the formation of these first solids, and the fact that the daughter elements correlate with the parent elements means that those daughters had to be derived from the decay of unstable parent elements after those solids were crystallized.

One of these SLRIs, iron-60, is only created in significant amounts by nuclear reactions in massive stars. The iron-60 must have come from a supernova, or from a giant star called an AGB star. Boss and Keiser's previous modeling showed that it was likely that a supernova triggered our Solar System's formation, as AGB star shocks are too thick to inject the iron-60 into the cloud. Supernova shocks are hundreds of times thinner, leading to more efficient injection.

Now Boss and Keiser have extended those models to 3-D, so they can see the shock wave striking the gas cloud, compressing it and forming a parabolic shock front that envelopes the cloud, creating finger-like indentations in the cloud's surface. The fingers inject the SLRI pollution from the supernova. Less than 0.1 million years later, the cloud collapses and forms the core of the protostar that became the Sun and its surrounding planets. The 3-D models show that only one or two fingers are likely to have caused the SLRI pollution found in primitive meteorites.

"The evidence leads us to believe that a supernova was indeed the culprit," said Boss. However, more detective work needs to be done: Boss and Keiser still need to find the combination of cloud and shock wave parameters that will line up perfectly with observations of exploding supernovae.

Source: Carnegie Institution

General Calendar:

Colloquia, Lectures, Seminars, Meetings, Open Houses & Tours:

Colloquia:  Carnegie (Tues. 4pm), UCLA, Caltech (Wed. 4pm), IPAC (Wed. 12:15pm) & other Pasadena (daily 12-4pm):  http://obs.carnegiescience.edu/seminars/ 

Carnegie astronomy lectures – only 4 per year in the Spring www.obs.carnegiescience.edu.    Visit www.huntington.org for directions.  For more information about the Carnegie Observatories or this lecture series, please contact Reed Haynie.

3 Aug

SBAS Monthly General Meeting at El Camino College planetarium. 7:30 PM Topic: “Dark Energy and Dark Matter” Dr. Michael Harrison:.  http://www.sbastro.net/.

13 Aug

LAAS LAAS General Meeting.

Griffith Observatory Event Horizon Theater 8:00 PM to 10:00 PM

16 Aug

AEA Astronomy Club       100-Year Low Earth Debris Population Model

Alan Jenkin (& Marlon Sorge)

Aerospace

A1/2143

August 16 & 17 The von Kármán Lecture Series:

The Voyager Mission to the Outer Planets and Interstellar Space

The Voyager mission legacy cannot be understated. The twin spacecraft gave us remarkable views of Jupiter, Saturn, Uranus and Neptune, unlike anything we had seen before, and paved the way for further exploration; the Galileo and Cassini spacecraft were direct descendants of the Voyager probes. Approaching their thirty-fifth anniversary, the Voyager twins continue to send us data from the farthest reaches of our solar system, at once enforcing and rewriting theories about this previously unexplored region. As they travel ever further, escaping all but our Sun’s constant but waning gravitational tug, the mission planners look forward to the next 10 – 15 years to hopefully witness the first spacecraft enter true, interstellar space.

Speaker:

Dr. Alan Cummings Member of the Professional Staff, Senior Scientist, Caltech

Locations:	Thursday, Aug 16, 2012, 7pm The von Kármán Auditorium at JPL 4800 Oak Grove Drive Pasadena, CA › Directions Friday, Aug 17, 2012, 7pm The Vosloh Forum at Pasadena City College 1570 East Colorado Blvd. Pasadena, CA › Directions
Webcast:	For the webcast on Thursday at 7 p.m. PST, click here If you don't have RealPlayer, you can download the free RealPlayer 8 Basic.

Observing:

The following data are from the 2012 Observer’s Handbook, and Sky & Telescope’s 2012 Skygazer’s Almanac & monthly Sky at a Glance.

A weekly 5 minute video about what’s up in the night sky:  www.skyandtelescope.com/skyweek.

Sun, Moon & Planets for August:

Moon: Aug 1 full, Aug 9 last quarter, Aug 17 new, Aug 23 1^st quarter, Aug 30 full                           

Planets:  Mercury is visible Aug. 10 to 31. Venus and Jupiter are visible in the pre-dawn sky.  Mars and Saturn are evening planets. 

Other Events:

6/7 Aug  Southern Iota Aquarid Meteor Shower Peak (6-7/hr)

11 Aug

SBAS Star Party (weather permitting): RPV at Ridgecrest Middle School 28915 North Bay Rd.

11-12 Aug The Perseid meteor shower peaks after midnight.

13 Aug Daytime occultation of Venus by the moon.  In L.A., begins about 1:40pm, ends about 2:48pm.

13/14 Aug Northern Delta Aquarid Meteor Shower Peak (10/hr)

14-22 Aug Mercury is more than 10 deg above the eastern horizon a half hour before sunrise.

18 Aug	LAAS Dark Sky Night : Lockwood Valley (Steve Kufeld Astronomical Site; LAAS members and their guests only)
18 Aug	SBAS out-of-town observing – contact Greg Benecke http://www.sbastro.net/.

18/19 Kappa Cygnid Meteor Shower Peak (6/hr)

25 Aug

Public  Star Party: Griffith Observatory Grounds 2-10pm

25/26 Aug Northern Iota Aquarid Meteor Shower Peak (5-10/hr)

Internet Links:
Link(s) of the Month

A weekly 5 minute video about what’s up in the night sky:  www.skyandtelescope.com/skyweek.

General

e! Science News Astronomy & Space

NASA Gallery

Astronomical Society of the Pacific (educational, amateur & professional)

Amateur Online Tools, Journals, Vendors, Societies, Databases

The Astronomy White Pages (U.S. & International Amateur Clubs & Societies)

American Astronomical Society (professional)

More...

Regional (esp. Southern California)

Western Amateur Astronomers (consortium of various regional societies)

Mt. Wilson Institute (www.mtwilson.edu/), including status for visits & roads

Los Angeles Astronomical Society (LAAS)

South Bay Astronomical Society (SBAS)

Orange County Astronomers

The Local Group Astronomy Club (Santa Clarita)

Ventura County Astronomical Society

About the Club

Club Websites:  Internal (Aerospace): https://aeropedia.aero.org/aeropedia/index.php/Astronomy_Club  It is updated to reflect this newsletter, in addition to a listing of past club mtg. presentations, astronomy news, photos & events from prior newsletters, club equipment, membership & constitution.  We have linked some presentation materials from past mtgs.  Our club newsletters are also being posted to an external blog, “An Astronomical View” http://astronomicalview.blogspot.com/. 

 
Membership.  For information, current dues & application, contact Jim Johansen, or see the club website where a form is also available.  Benefits will include use of club telescope(s) & library/software, discounts on Sky & Telescope magazine and Observer’s Handbook, field trips, great programs, having a say in club activities, acquisitions & elections, etc.

Committee Suggestions & Volunteers.  Feel free to contact:  Paul Rousseau, Program Committee Chairman (& club VP), TBD, Activities Committee Chairman (& club Secretary), or Jim Johansen, Resource Committee Chairman (over equipment & library, and club Treasurer).

Mark Clayson,
AEA Astronomy Club President

2012 July

AEA Astronomy Club Newsletter, July 2012

Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 1
Astronomy News p. 6
General Calendar p. 8
    Colloquia, lectures, mtgs. p. 8
    Observing p. 9
Useful Links p. 10
About the Club p. 11

Club News & Calendar.

Calendar

19 July

Monthly Meeting

Astrophotography & Research at an Amateur Observatory, Francis Longstaff, Polaris Observatory Assn. (amateur/pro collaboration) & UCLA Faculty & Saturn Lodge 0.7m amateur telescope.  A1/1029A/B

AEA Astronomy Club meetings are on 3^rd Thursdays at 11:45am.  For 2012, April-May we meet in A1/1026; June-July & Oct.-Dec. in A1/1029A/B; Aug. in A1/2143 and Sept. in A3/1607A/B.

News:  

An order has been placed for the Mallincam Extreme video camera, along with an f/3 focal reducer.  Expected delivery in 2 months.

Based on the FY 2013 wish list circulated among club members, it appears our request to AEA, to be submitted July 16, will be $4,200.

Astronomy Video(s) & Picture(s) of the Month

(from Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html)
Video(s)
Fireworks Over Mars: The Spirit of 76 Pyrotechnics
http://www.jpl.nasa.gov/news/news.cfm?release=2012-192&cid=release_2012-192

Journey to the Center of the Galaxy http://apod.nasa.gov/apod/ap120702.html

2012 June 18

Milky Way Above Easter Island
Image Credit & Copyright: Manel Soria

Explanation: Why were the statues on Easter Island built? No one is sure. What is sure is that over 800 large stone statues exist there. The Easter Island statues, stand, on the average, over twice as tall as a person and have over 200 times as much mass. Few specifics are known about the history or meaning of the unusual statues, but many believe that they were created about 500 years ago in the images of local leaders of a lost civilization. Pictured above, some of the stone giants were illuminated in 2009 under the central band of our Milky Way Galaxy.

2012 July 8

Volcano and Aurora in Iceland
Image Credit & Copyright: Sigurdur H. Stefnisson

Explanation: Sometimes both heaven and Earth erupt. In Iceland in 1991, the volcano Hekla erupted at the same time that auroras were visible overhead. Hekla, one of the most famous volcanoes in the world, has erupted at least 20 times over the past millennium, sometimes causing great destruction. The last eruption occurred only twelve years ago but caused only minor damage. The green auroral band occurred fortuitously about 100 kilometers above the erupting lava. Is Earth the Solar System's only planet with both auroras and volcanos?

2012 June 27

Simeis 188 in Stars, Dust and Gas
Image Credit & Copyright: Dieter Willasch (Astro-Cabinet)

Explanation: When stars form, pandemonium reigns. A particularly colorful case is the star forming region Simeis 188 which houses an unusual and bright cloud arc cataloged as NGC 6559. Visible above are red glowing emission nebulas of hydrogen, blue reflection nebulas of dust, dark absorption nebulas of dust, and the stars that formed from them. The first massive stars formed from the dense gas will emit energetic light and winds that erode, fragment, and sculpt their birthplace. And then they explode. The resulting morass can be as beautiful as it is complex. After tens of millions of years, the dust boils away, the gas gets swept away, and all that is left is a naked open cluster of stars. Simeis 188 is located about 4,000 light years away and can be found about one degree northeast of M8, the Lagoon Nebula.

2012 June 17

Jupiter's Rings Revealed
Image Credit: M. Belton (NOAO), J. Burns (Cornell) et al., Galileo Project, JPL, NASA

Explanation: Why does Jupiter have rings? Jupiter's rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft that orbited Jupiter from 1995 to 2003 later confirmed that these rings were created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Adrastea, for example, it will bore into the moon, vaporize, and explode dirt and dust off into a Jovian orbit. Pictured above is an eclipse of the Sun by Jupiter, as viewed from Galileo. Small dust particles high in Jupiter's atmosphere, as well as the dust particles that compose the rings, can be seen by reflected sunlight.

2012 July 1

The Outer Shells of Centaurus A
Image Credit: E. Peng and H. Ford (JHU), K. Freeman (ANU), R. White (STScI), CTIO, NOAO, NSF

Explanation: What causes the surrounding shells in peculiar galaxy Cen A? In 2002 a fascinating image of peculiar galaxy Centaurus A was released, processed to highlight a faint blue arc indicating an ongoing collision with a smaller galaxy. Another interesting feature of Cen A, however, is the surrounding system of shells, better visible here in this recently released wider pan from the four meter Blanco telescope at Cerro Tololo Inter-American Observatory. Faint shells around galaxies are not unusual and considered by themselves as evidence of a previous galaxy merger, analogous to water ripples on a pond. An unexpected attribute of these shells is the abundance of gas, which should become separated from existing stars during the collision.

Astronomy News:

(from e! Science News Astronomy & Space)

"God Particle" Found? "Historic Milestone" From Higgs Boson Hunters

Newfound particle may be at the core of existence.

Ker Than for National Geographic News Published July 4, 2012

"I think we have it. You agree?"


Speaking to a packed audience Wednesday morning in Geneva, CERN director general Rolf Heuer confirmed that two separate teams working at the Large Hadron Collider (LHC) are more than 99 percent certain they've discovered the Higgs boson, aka the God particle—or at the least a brand-new particle exactly where they expected the Higgs to be.


The long-sought particle may complete the standard model of physics by explaining why objects in our universe have mass—and in so doing, why galaxies, planets, and even humans have any right to exist.
(See Large Hadron Collider pictures.)


"We have a discovery," Heuer said at the seminar. "We have observed a new particle consistent with a Higgs boson."


At the meeting were four theorists who helped develop the Higgs theory in the 1960s, including Peter Higgs himself, who could be seen wiping away tears as the announcement was made.


Although preliminary, the results show a so-called five-sigma of significance, which means that there is only a one in a million chance that the Higgs-like signal the teams observed is a statistical fluke.


"It's a tremendous and exciting time," said physicist Michael Tuts, who works with the ATLAS (A Toroidal LHC Apparatus) Experiment, one of the two Higgs-seeking LHC projects.


The Columbia University physicist had organized a wee-hours gathering of physicists and students in the U.S. to watch the announcement, which took place at 9 a.m., Geneva time.


"This is the payoff. This is what you do it for."


The two LHC teams searching for the Higgs—the other being the CMS (Compact Muon Solenoid) project—did so independently. Neither one knew what the other would present this morning.


"It was interesting that the competing experiment essentially had the same result," said physicist Ryszard Stroynowski, an ATLAS team member based at Southern Methodist University in Dallas. "It provides additional confirmation."


CERN head Heuer called today's announcement a "historic milestone" but cautioned that much work lies ahead as physicists attempt to confirm the newfound particle's identity and further probe its properties.


For example, though the teams are certain the new particle has the proper mass for the predicted Higgs boson, they still need to determine whether it behaves as the God particle is thought to behave—and therefore what its role in the creation and maintenance of the universe is.


"I think we can all be proud ... but it's a beginning," Heuer said.


[for the rest of the article, go to http://news.nationalgeographic.com/news/2012/07/120704-god-particle-higgs-boson-new-cern-science/]

Milky Way struck 100 million years ago, still rings like a bell

Published: Thursday, June 28, 2012 - 14:06 in Astronomy & Space

An international team of astronomers have discovered evidence that our Milky Way had an encounter with a small galaxy or massive dark matter structure perhaps as recently as 100 million years ago, and as a result of that encounter it is still ringing like a bell. The discovery is based on observations of 300,000 nearby Milky Way stars by the Sloan Digital Sky Survey (SDSS). Stars in the disk of the Milky Way move up and down at a speed of about 20-30 kilometers per second while orbiting the center of the galaxy at a brisk 220 kilometers per second. The positions and motions of these nearby stars weren't quite as regular as previously thought, according to the study results.


"We clearly observe unexpected differences in the Milky Way's stellar distribution above and below the Galaxy's mid-plane having the appearance of a vertical wave -- something that nobody has seen before," says Queen's University physicist Larry Widrow, lead researcher on the project.
The researchers have not been able to identify the celestial object that passed through the Milky Way. It could have been one of the small satellite galaxies that move around the center of our galaxy, or an invisible structure such as a dark matter halo. It might not have been a single isolated event in the past, and it may even be ongoing.


The researchers discovered a small but statistically significant difference in the distribution of stars north and south of the Milky Way's midplane when analyzing SDSS data. For more than a year, they explored various explanations of this north-south asymmetry but were unable to solve the mystery. So they began exploring whether the data was telling them something about recent events in the Galaxy's history.
Scientists know of more than 20 visible satellite galaxies that circle the center of the Milky Way, with masses ranging from one million to one billion solar masses. There may also be invisible satellites made of dark matter. There is six times as much dark matter in the universe as ordinary, visible matter. Astronomers' computer simulations have found that this invisible matter formed hundreds of massive structures that move around our Milky Way.


These dark matter satellites, because of their abundance, are more likely than the visible satellite galaxies to cut through the Milky Way's mid-plane and cause vertical waves.
Computer simulations indicate that over the next 100 million years or so, our galaxy will "stop ringing." The north-south asymmetry will disappear and the vertical motions of stars in the solar neighborhood will revert back to their equilibrium orbits unless we get hit again.
Collaborators on the project include Brian Yanny and Scott Dodelson (US Department of Energy's Fermilab), Susan Gardner, (University of Kentucky) and Hsin-Yu Chen (University of Chicago).

Source: Queen's University

General Calendar:

Colloquia, Lectures, Seminars, Meetings, Open Houses & Tours:

Note:  The South Bay Astronomical Society website has changed from www.sbastro.org to http://www.sbastro.net/.

Colloquia:  Carnegie (Tues. 4pm), UCLA, Caltech (Wed. 4pm), IPAC (Wed. 12:15pm) & other Pasadena (daily 12-4pm):  http://obs.carnegiescience.edu/seminars/ 

Carnegie astronomy lectures – only 4 per year in the Spring www.obs.carnegiescience.edu.    Visit www.huntington.org for directions.  For more information about the Carnegie Observatories or this lecture series, please contact Reed Haynie.

6 July

SBAS Monthly General Meeting at El Camino College planetarium. 7:30 PM Topic: TBD Guest Speaker:.  http://www.sbastro.net/.

9 July

LAAS LAAS General Meeting.

Griffith Observatory Event Horizon Theater 8:00 PM to 10:00 PM

19 July

AEA Astronomy Club  Meeting

Astrophotography & Research at an Amateur Observatory, Francis Longstaff, Polaris Observatory Assn. (amateur/pro collaboration) & UCLA Faculty & Saturn Lodge 0.7m amateur telescope.  A1/1029A/B

Jul 19 & 20 The von Kármán Lecture Series:

The Power of Two: How Humans and Robots Explore Space

From robotic scouting missions, to space station construction, to opening the planetary frontiers, there has been a growing relationship between robots and humans. The first robotic scouts to the Moon answered key science and engineering questions, paving the path for the Apollo landings. Now Mars is under the robotic magnifying glass, both from orbit and from its surface. The International Space Station was constructed using robotic arms and manipulators, as well as space walks. The next generation of human explorers will have the advantage of even more capable robotic aids and support systems. This talk explores the evolving nature of the relationship between humans and robots engaged in the exploration of space.

Speaker:

Garry Burdick Manager, Human/Robotic Mission Systems Office, JPL

Locations:	Thursday, July 19, 2012, 7pm The von Kármán Auditorium at JPL 4800 Oak Grove Drive Pasadena, CA › Directions Friday, July 20, 2012, 7pm The Vosloh Forum at Pasadena City College 1570 East Colorado Blvd. Pasadena, CA › Directions
Webcast:	For the webcast on Thursday at 7 p.m. PST, click here If you don't have RealPlayer, you can download the free RealPlayer 8 Basic.

Observing:

The following data are from the 2012 Observer’s Handbook, and Sky & Telescope’s 2012 Skygazer’s Almanac & monthly Sky at a Glance.

A weekly 5 minute video about what’s up in the night sky:  www.skyandtelescope.com/skyweek.

Sun, Moon & Planets for April:

Moon Phases:  July 3 full, July 11 last quarter, July 18 new, July 25 1st quarter

Planets:  Venus and Jupiter are visible in the pre-dawn sky.  Mercury, Mars and Saturn are all Evening planets.  

Other Events:

14 July

SBAS Star Party (weather permitting): RPV at Ridgecrest Middle School 28915 North Bay Rd.

21 July	LAAS Dark Sky Night : Lockwood Valley (Steve Kufeld Astronomical Site; LAAS members and their guests only)
21 July	SBAS out-of-town observing – contact Greg Benecke http://www.sbastro.net/.

28 July

Public  Star Party: Griffith Observatory Grounds 2-10pm

28-29 July Saturday – Sunday Delta Aquarid Meteor Shower

At peak time about 20 bright, yellow meteors can be observed per hour. Because these

meteors nearly broadside the Earth, their speed is a moderate 25.5 miles per second.

29-30 July Sunday – Monday Capricornid Meteor Shower

The Capricornids are characterized by their often yellow coloration and their frequent

brightness. They are also slow interplanetary interlopers, hitting our atmosphere at around

15 miles per second. Though you can expect only 15 meteors per hour at best under dark

sky conditions, the Capricornids are noted for producing brilliant fireballs.

Internet Links:
Link(s) of the Month

A weekly 5 minute video about what’s up in the night sky:  www.skyandtelescope.com/skyweek.

General

e! Science News Astronomy & Space

NASA Gallery

Astronomical Society of the Pacific (educational, amateur & professional)

Amateur Online Tools, Journals, Vendors, Societies, Databases

The Astronomy White Pages (U.S. & International Amateur Clubs & Societies)

American Astronomical Society (professional)

More...

Regional (esp. Southern California)

Western Amateur Astronomers (consortium of various regional societies)

Mt. Wilson Institute (www.mtwilson.edu/), including status for visits & roads

Los Angeles Astronomical Society (LAAS)

South Bay Astronomical Society (SBAS)

Orange County Astronomers

The Local Group Astronomy Club (Santa Clarita)

Ventura County Astronomical Society

About the Club

Club Websites:  Internal (Aerospace): https://aeropedia.aero.org/aeropedia/index.php/Astronomy_Club  It is updated to reflect this newsletter, in addition to a listing of past club mtg. presentations, astronomy news, photos & events from prior newsletters, club equipment, membership & constitution.  We have linked some presentation materials from past mtgs.  Our club newsletters are also being posted to an external blog, “An Astronomical View” http://astronomicalview.blogspot.com/. 

 
Membership.  For information, current dues & application, contact Jim Johansen, or see the club website where a form is also available.  Benefits will include use of club telescope(s) & library/software, discounts on Sky & Telescope magazine and Observer’s Handbook, field trips, great programs, having a say in club activities, acquisitions & elections, etc.

Committee Suggestions & Volunteers.  Feel free to contact:  Paul Rousseau, Program Committee Chairman (& club VP), TBD, Activities Committee Chairman (& club Secretary), or Jim Johansen, Resource Committee Chairman (over equipment & library, and club Treasurer).

Mark Clayson,
AEA Astronomy Club President