The Hubble Ultra Deep Field Image (see description on the right, below)

The Hubble Ultra Deep Field Image
(10,000 galaxies in an area 1% of the apparent size of the moon -- see description on the right, below)

Friday, March 15, 2013

2013 March


AEA Astronomy Club Newsletter                      March  2013

Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 2
Astronomy News p. 7
General Calendar p.9
    Colloquia, lectures, mtgs. p. 9
    Observing p. 10
Useful Links p. 11

About the Club p. 12

Club News & Calendar.

Calendar

Club Meeting Schedule:
21 March 2013
Club Meeting
Grand Tour of the Universe
Mark Clayson, Aerospace
A1/1735
18 (or 16?) April 2013
Club Meeting (or Corporate Colloquium?)
Einstein for Everyone
Robert Piccioni, UCLA
A1/1735
16 May 2013
Club Meeting
Cassini Update
Dave Doody, JPL
A1/1735
20 June 2013
Club Meeting & Pizza Party
The Chemical Makeup of Exosolar Planets
Dr. Steven Naftilan, Claremont College
A1/1735

AEA Astronomy Club meetings are on 3rd Thursdays at 11:45am.  For all of 2013, the meeting room is A1/1735.

News:  

The March 21 club mtg. – back “by popular demand,” Mark Clayson will give an updated Grand Tour of the Universe.  It was given 3 years ago, but we have many new members who haven’t seen it.  Hubble & other photos of the broad variety of celestial objects & the universe as a whole, and a bit about them, their evolution, etc. 

Amateur Observatory.  Suggestions for facilities at the proposed cooperative amateur observatory in Palos Verdes so far include:  cement pad(s) w. power, wind shelter (roofless or retractable roof or dome), permanent table (like picnic-style?).  Other suggestions?  WiFi for live streaming of our video camera images to the internet?

Results of voting on proposed membership bylaw amendment.  8 of 9 voted in favor of the proposal.  The negative was concerned over the status of RIFees – whether full or associate members.  The AEA officers weighed in, and indicated no concern over full membership status for them.  The amendment passes, as follows:

Bylaws Section 1 Limitations
Membership is limited to employees and former employees of The Aerospace Corporation.  Associate Membership is open to all others.  The Bylaws of the AEA shall apply to Members and Associate Members of the Astronomy Club.  The terms “membership” and “member” are used to include both membership categories.

Field Trip.  There have been few responses so far on the survey of interests in candidate club field trips for the year.  Unless additional responses come in, we table it for now. Ideas include:  Mt. Palomar tour & star party/camping, JPL tour (or open house in June), Griffith Observatory, Calif. Science Museum (incl. Endeavor, IMAX,...), the Columbia Memorial Space Center in Downey (Apollo & Shuttle history),.... Other suggestions?

Membership Renewals.  Just a reminder that for most of us, our club membership expired Dec. 31 (except those who joined in the last few months and likely paid also for 2012).  We invite you to renew for 2013 at your earliest convenience.  See the club website for the many other benefits of membership.  Please submit the renewal form (available on Aerolink at https://aerolink.aero.org/cs/llisapi.dll?func=ll&objId=13659520&objAction=browse&viewType=1, or attached) with your payment ($12 check made out to AEA Astronomy Club) to Alan Olson at M1-107.

New Regular Mtg. Room.  A reminder that we have secured a new, and hopefully steady, meeting room for all of 2013 (beginning Jan. 17):  A1/1735.  It is a large room w. large conference table seating 13, and chairs for 25 more on the sides.  It is located near the NE corner of the bldg.:  from the main lobby, turn right immediately after the credit union entrance (thru the badge reader), and at the end of that hall turn left, then right again, and it's on the right.  If accessing from the door at the NE corner of A1 (near the bridge to LAAFB), turn left after entering & go thru the 2 sets of doors straight ahead.

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

The Great Russian Meteor of 2013 http://apod.nasa.gov/apod/ap130218.html
Video Credit & Copyright:
RussiaToday
Explanation: What in heaven's blazes is that? Thousands of people living near the Ural Mountains in Russia saw last Friday morning one of the more spectacular meteors of modern times streak across the sky. Forceful sound waves arrived at the ground minutes later, knocking people over and breaking windows for hundreds of kilometers. The above video is a compilation of several car dashcams and includes real time footage of the meteor rampaging, smoke trails drifting, shadows quickly shifting, and even the meteor's light reflecting off the back of a bus. The fireball is thought to have been caused by a car-sized chunk of ice and rock crashing into the Earth's atmosphere. Since the event was captured from so many angles, the meteor's trajectory has become determined well enough to indicate from where it came and to where any resultant pieces might have landed. It is already certain that this meteor had nothing to do with the several-times larger asteroid 2012 DA14 which passed the Earth from a different direction later the same day. If pieces of the meteor are found, they might tell humanity more about the early Solar System, when the meteor was likely formed.

Asteroid 2012 DA14 Passes the Earth http://apod.nasa.gov/apod/ap130217.html
Video Credit & Copyright:
Daniel López (El Cielo de Canarias)
Explanation: There it goes. That small spot moving in front of background stars in the above video is a potentially dangerous asteroid passing above the Earth's atmosphere. This past Friday, the 50-meter wide asteroid 2012 DA14 just missed the Earth, passing not only inside the orbit of the Moon, which is unusually close for an asteroid of this size, but also inside the orbit of geosynchronous satellites. Unfortunately, asteroids this big or bigger strike the Earth every 1000 years or so. Were 2012 DA14 to have hit the Earth, it could have devastated a city-sized landscape, or stuck an ocean and raised dangerous tsunamis. Although finding and tracking potentially dangerous asteroids is a primary concern of modern astronomy, these small bodies or ice and rock are typically so dim that only a few percent of them have been found, so far. Even smaller chunks of ice and rock, like the (unrelated) spectacular meteors that streaked over Russia and California over the past few days, are even harder to find -- but pose less danger.

Coronal Rain on the Sun http://apod.nasa.gov/apod/ap130226.html
Video Credit:
Solar Dynamics Observatory, SVS, GSFC, NASA; Music: Thunderbolt by Lars Leonhard
Explanation: Does it rain on the Sun? Yes, although what falls is not water but extremely hot plasma. An example occurred in mid-July 2012 after an eruption on the Sun that produced both a Coronal Mass Ejection and a moderate solar flare. What was more unusual, however, was what happened next. Plasma in the nearby solar corona was imaged cooling and falling back, a phenomenon known as coronal rain. Because they are electrically charged, electrons, protons, and ions in the rain were gracefully channeled along existing magnetic loops near the Sun's surface, making the scene appear as a surreal three-dimensional sourceless waterfall. The resulting surprisingly-serene spectacle is shown in ultraviolet light and highlights matter glowing at a temperature of about 50,000 Kelvin. Each second in the above time lapse video takes about 6 minutes in real time, so that the entire coronal rain sequence lasted about 10 hours.



2013 February 23 
Chelyabinsk Meteor Flash 
Image Credit & 
CopyrightMarat Ahmetvaleev
Explanation: A meteoroid fell to Earth on February 15, streaking some 20 to 30 kilometers above the city of Chelyabinsk, Russia at 9:20am local time. Initially traveling at about 20 kilometers per second, its explosive deceleration after impact with the lower atmosphere created a flash brighter than the Sun. This picture of the brilliant bolide (and others of its persistent trail) was captured by photographer Marat Ametvaleev, surprised during his morning sunrise session creating panoramic images of the nearby frosty landscape. An estimated 500 kilotons of energy was released by the explosion of the 17 meter wide space rock with a mass of 7,000 to 10,000 tons. Actually expected to occur on average once every 100 years, the magnitude of the Chelyabinsk event is the largest known since the Tunguska impact in 1908.




2013 March 2
Miass River Sunrise
Image Credit &
Copyright: Marat Ahmetvaleev
Explanation: Each day on planet Earth can have a serene beginning at sunrise as the sky gently grows bright over a golden eastern horizon. This sunrise panorama seems to show such a moment on the winter morning of February 15. In the mist, a calm, mirror-like stretch of the Miass River flows through the foreground along a frosty landscape near Chelyabinsk, Russia. But the long cloud wafting through the blue sky above is the evolving persistent train of the Chelyabinsk Meteor. The vapor trail was left by the space rock that exploded over the city only 18 minutes earlier, causing extensive damage and injuring over 1,000 people. A well-documented event, the numerous webcam and dashcam video captures from the region soon contributed to a reconstruction of the meteor's trajectory and an initial orbit determination. Preliminary findings indicate the parent meteoriod belonged to the Apollo class of Earth crossing asteroids.

Reflected Aurora Over Alaska 


Image Credit & Copyright: Todd Salat (AuroraHunter); Sky Annotation: Judy Schmidt
Explanation: Some auroras can only be seen with a camera. They are called subvisual and are too faint to be seen with the unaided eye. In the above image, the green aurora were easily visible to the eye, but the red aurora only became apparent after a 20-second camera exposure. The reason is that the human eye only accumulates light for a fraction of a second at a time, while a camera shutter can be left open much longer. When photographing an already picturesque scene near AnchorageAlaskaUSA, last autumn, a camera caught both the visual green and subvisual red aurora reflected in a lily pad-covered lake. High above, thousands of stars were visible including the Pleiades star cluster, while the planet Jupiter posed near the horizon, just above clouds, toward the image right. Auroras are caused by energetic particles from the Sun impacting the Earth's magnetosphere, causing electrons and protons to rain down near the Earth's poles and impact the air. Both red and green aurora are typically created by excited oxygen atoms, with red emission, when visible, dominating higher up. Auroras are known to have many shapes and colors.


2013 March 6


Tardigrade in Moss
Image Credit & Copyright: Nicole Ottawa & Oliver Meckes / Eye of Science /
Science Source Images
Explanation: Is this an alien? Probably not, but of all the animals on Earth, the tardigrade might be the best candidate. That's because tardigrades are known to be able to go for decades without food or water, to survive temperatures from near absolute zero to well above the boiling point of water, to survive pressures from near zero to well above that on ocean floors, and to survive direct exposure to dangerous radiations. The far-ranging survivability of these extremophiles was tested in 2011 outside an orbiting space shuttle. Tardigrades are so durable partly because they can repair their own DNA and reduce their body water content to a few percent. Some of these miniature water-bears almost became extraterrestrials recently when they were launched toward to the Martian moon Phobos on board the Russian mission Fobos-Grunt, but stayed terrestrial when a rocket failed and the capsule remained in Earth orbit. Tardigrades are more common than humans across most of the Earth. Pictured above in a color-enhanced electron micrograph, a millimeter-long tardigrade crawls on moss.

Astronomy News:

A window into Europa's ocean lies right at the surface

Published: Tuesday, March 5, 2013 - 14:33 in Astronomy & Space

Related images


<p>NASA/JPL-Caltech

If you could lick the surface of Jupiter's icy moon Europa, you would actually be sampling a bit of the ocean beneath. So says Mike Brown, an astronomer at the California Institute of Technology (Caltech). Brown -- known as the Pluto killer for discovering a Kuiper-belt object that led to the demotion of Pluto from planetary status -- and Kevin Hand from the Jet Propulsion Laboratory (JPL) have found the strongest evidence yet that salty water from the vast liquid ocean beneath Europa's frozen exterior actually makes its way to the surface. The finding, based on some of the first data of its kind since NASA's Galileo mission (1989-2003) to study Jupiter and its moons, suggests that there is a chemical exchange between the ocean and surface, making the ocean a richer chemical environment, and implies that learning more about the ocean could be as simple as analyzing the moon's surface. The work is described in a paper that has been accepted for publication in the Astronomical Journal.

"We now have evidence that Europa's ocean is not isolated -- that the ocean and the surface talk to each other and exchange chemicals," says Brown, the Richard and Barbara Rosenberg Professor and professor of planetary astronomy at Caltech. "That means that energy might be going into the ocean, which is important in terms of the possibilities for life there. It also means that if you'd like to know what's in the ocean, you can just go to the surface and scrape some off."

"The surface ice is providing us a window into that potentially habitable ocean below," says Hand, deputy chief scientist for solar system exploration at JPL.

Since the days of the Galileo mission, when the spacecraft showed that Europa was covered with an icy shell, scientists have debated the composition of Europa's surface. The infrared spectrometer aboard Galileo was not capable of providing the detail needed to definitively identify some of the materials present on the surface. Now, using current technology on ground-based telescopes, Brown and Hand have identified a spectroscopic feature on Europa's surface that indicates the presence of a magnesium sulfate salt, a mineral called epsomite, that could only originate from the ocean below.

"Magnesium should not be on the surface of Europa unless it's coming from the ocean," Brown says. "So that means ocean water gets onto the surface, and stuff on the surface presumably gets into the ocean water."
Europa's ocean is thought to be 100 kilometers deep and covers the entire globe. The moon remains locked in relation to Jupiter, with the same hemisphere always leading and the other trailing in its orbit. The leading hemisphere has a yellowish appearance, while the trailing hemisphere seems to be splattered and streaked with a red material.

The spectroscopic data from that red side has been a cause of scientific debate for 15 years. It is thought that one of Jupiter's largest moons, Io, spews volcanic sulfur from its atmosphere, and Jupiter's strong magnetic field sends some of that sulfur hurtling toward the trailing hemisphere of Europa, where it sticks. It is also clear from Galileo's data that there is something other than pure water ice on the trailing hemisphere's surface. The debate has focused on what that other something is -- i.e., what has caused the spectroscopic data to deviate from the signature of pure water ice.

"From Galileo's spectra, people knew something was there besides water. They argued for years over what it might be -- sodium sulfate, hydrogen sulfate, sodium hydrogen carbonate, all these things that look more or less similar in this range of the spectrum," says Brown. "But the really difficult thing was that the spectrometer on the Galileo spacecraft was just too coarse."

Brown and Hand decided that the latest spectrometers on ground-based telescopes could improve the data pertaining to Europa, even from a distance of about 400 million miles. Using the Keck II telescope on Mauna Kea -- which is outfitted with adaptive optics to adjust for the blurring effect of Earth's atmosphere -- and its OH-Suppressing Infrared Integral Field Spectrograph (OSIRIS), they first mapped the distribution of pure water ice versus anything else on the moon. The spectra showed that even Europa's leading hemisphere contains significant amounts of nonwater ice. Then, at low latitudes on the trailing hemisphere -- the area with the greatest concentration of the nonwater ice material -- they found a tiny dip in the spectrum that had never been detected before.

"We now have the best spectrum of this thing in the world," Brown says. "Nobody knew there was this little dip in the spectrum because no one had the resolution to zoom in on it before."

The two researchers racked their brains to come up with materials that might explain the new spectroscopic feature, and then tested everything from sodium chloride to Drano in Hand's lab at JPL, where he tries to simulate the environments found on various icy worlds. "We tried to think outside the box to consider all sorts of other possibilities, but at the end of the day, the magnesium sulfate persisted," Hand says.

Some scientists had long suspected that magnesium sulfate was on the surface of Europa. But, Brown says, "the interesting twist is that it doesn't look like the magnesium sulfate is coming from the ocean." Since the mineral he and Hand found is only on the trailing side, where the moon is being bombarded with sulfur from Io, they believe that there is a magnesium-bearing mineral everywhere on Europa that produces magnesium sulfate in combination with sulfur. The pervasive magnesium-bearing mineral might also be what makes up the nonwater ice detected on the leading hemisphere's surface.

Brown and Hand believe that this mystery magnesium-bearing mineral is magnesium chloride. But magnesium is not the only unexpected element on the surface of Europa. Fifteen years ago, Brown showed that Europa is surrounded by an atmosphere of atomic sodium and potassium, presumably originating from the surface. The researchers reason that the sodium and potassium chlorides are actually the dominant salts on the surface of Europa, but that they are not detectable because they have no clear spectral features.

The scientists combined this information with the fact that Europa's ocean can only be one of two types -- either sulfate-rich or chlorine-rich. Having ruled out the sulfate-rich version since magnesium sulfate was found only on the trailing side, Brown and Hand hypothesize that the ocean is chlorine-rich and that the sodium and potassium must be present as chlorides.

Therefore, Brown says, they believe the composition of Europa's sea closely resembles the salty ocean of Earth. "If you could go swim down in the ocean of Europa and taste it, it would just taste like normal old salt," he says.
Hand emphasizes that, from an astrobiology standpoint, Europa is considered a premier target in the search for life beyond Earth; a NASA-funded study team led by JPL and the Johns Hopkins University Applied Physics Laboratory have been working with the scientific community to identify options to explore Europa further. "If we've learned anything about life on Earth, it's that where there's liquid water, there's generally life," Hand says. "And of course our ocean is a nice salty ocean. Perhaps Europa's salty ocean is also a wonderful place for life."
The Astronomical Journal paper is titled "Salts and radiation products on the surface of Europa." The work was supported, in part, by the NASA Astrobiology Institute through the Astrobiology of Icy Worlds node at JPL.

Source: California Institute of Technology



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.    For 2013:  April 8 & 22, May 6 & 20.  Visit www.huntington.org for directions.  For more information about the Carnegie Observatories or this lecture series, please contact Reed Haynie.

1 March
SBAS Monthly General Meeting at El Camino College planetarium. 7:30 PM
Topic: Landing Curiosity, Speaker: Dr. Keith Comeaux, JPL Flight Director

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

Mar. 14 & 15 The von Kármán Lecture Series: 2013


There and Back Again: The Migration of Robotic Arm Technology from Mars to Earth

While robotic arm applications on Earth have existed for decades, it's only in the last few years that manipulation jobs have moved far outside the factory walls. We now look for arms capable of tasks such as ordinance disposal, underwater operations, and disaster response. It is in this last area that JPL will immediately apply all its lessons learned from the Mars surface missions to a terrestrial application, DARPA's Robotic Challenge ( www.theroboticchallenge.org ). This talk will provide an overview of the challenges of the design and use of Curiosity's Robotic Arm and followed by a description of those same challenges faced by JPL's RoboSimian robot, which will compete in the Robotic Challenge. In particular, we'll look at what makes those robotic systems kissing cousins as well as worlds apart.
Speaker:
Brett Kennedy Supervisor, Robotic Vehicles and Manipulators Group Cognizant Engineer, MSL Robotic Arm

Locations:
Thursday, Mar. 14, 2012, 7pm
The von Kármán Auditorium
at JPL
4800 Oak Grove Drive
Pasadena, CA
› Directions

Friday, Mar. 15, 2012, 7pm
The Vosloh Forum at Pasadena City College
1570 East Colorado Blvd.
Pasadena, CA
› Directions

Webcast:
We offer two options to view the live streaming of our webcast on Thursday:
› 1) Ustream with real-time web chat to take public questions.
› 2)
Flash Player with open captioning
If you don't have Flash Player, you can download for free
here.



21 Mar 2013
AEA Astronomy Club mtg.
Grand Tour of the Universe
Mark Clayson
A1/1735


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 March:


Moon: Mar 4 last quarter, Mar 11 new, Mar 19 1st quarter, Mar 27 full                                
PlanetsMars & Mercury are visible briefly in the evening twilight in the West. Jupiter rises before sunset and is visible until about 2am. Saturn is visible from about midnight to sunrise.  Venus is visible briefly in the East before sunrise. 
Other Events:

1 March Spica 0.1 deg. N of Moon

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


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

10 March Daylight Savings time begins

Mid-March: Comet PanSTARRS, the 1st of 2 bright comets for 2013 – the other will be ISON in December.  PanSTARRS is expected to “glow at magnitude zero or brighter low (~ 10 deg. elevation 45 minutes after sunset) in the western evening twilight around the middle of March for viewers at mid-northern latitudes.”  It should persist, though fading, into April.

16 March
Public  Star Party: Griffith Observatory Grounds 2-10pm

18 March Jupiter 1.5 deg. N of Moon

20 March Vernal Equinox


28 March Spica 0.1 deg. N of Moon

31 March Mercury greatest elongation West (28 deg.)

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


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 Alan Olson, or see the club website (or Aerolink folder) where a form is also available (go to the membership link/folder & look at the bottom).  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:  Mark Clayson, Program Committee Chairman (& acting club VP), TBD, Activities Committee Chairman (& club Secretary), or Alan Olson, Resource Committee Chairman (over equipment & library, and club Treasurer).

Mark Clayson,
AEA Astronomy Club President

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