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)

Sunday, June 7, 2015

2015 June

AEA Astronomy Club Newsletter  June  2015

Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 1
Astronomy News p. 8
General Calendar p.11
    Colloquia, lectures, mtgs. p. 11
    Observing p. 13
Useful Links p. 14
About the Club p. 15

Club News & Calendar.

Club Calendar

Club Meeting Schedule:


4 June
AEA Astronomy Club Meeting
A DVD from our Library 

A1/1735





2 July
AEA Astronomy Club Meeting
Pizza Party, Planetary Society Speaker
Mat Kaplan
A1/1735

AEA Astronomy Club meetings are now on 1st  Thursdays at 11:45am.  For all of 2015, the meeting room is A1/1735. 

Club News:  

For our July 2 mtg., in addition to the regular quarterly pizza, we’ll have a guest speaker – Mat Kaplan is the Planetary Society Radio Producer and Host.  He will talk about the work of the Society, and his experiences as a science and space reporter for several decades.

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

(from Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html)
Mapping our Supercluster:  https://youtu.be/rENyyRwxpHo
Published on Sep 3, 2014
Superclusters – regions of space that are densely packed with galaxies – are the biggest structures in the Universe. But scientists have struggled to define exactly where one supercluster ends and another begins. Now, a team based in Hawaii has come up with a new technique that maps the Universe according to the flow of galaxies across space. Redrawing the boundaries of the cosmic map, they redefine our home supercluster and name it Laniakea, which means ‘immeasurable heaven’ in Hawaiian.

Read the research paper: http://dx.doi.org/10.1038/nature13674
Read Nature's news story: http://www.nature.com/news/earth-s-ne... 

Approaching Pluto http://apod.nasa.gov/apod/ap150527.html
Video Credit: NASA, Johns Hopkins U. Applied Physics Lab., Southwest Research Inst.
Explanation: Here comes Pluto. NASA's robotic New Horizons spacecraft is now beyond the orbit of Neptune and closing fast on the Solar System's most famous unexplored world. The featured time lapse video shows Pluto and Pluto's largest moon, Charon, orbiting their common center of mass in 13 frames taken from April 12 to April 18. Although blurry, images in the video now rival even the best images of Pluto yet taken from Earth. New Horizons remains on schedule to zoom past the distant dwarf planet on July 14.


Two Worlds, One Sun 
Left Image Credit & Copyright: Damia Bouic; 
Right Image Credit: NASA, JPL-Caltech, MSSS; Digital processing: Damia Bouic
Explanation: How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have same angular width and featured here side-by-side. A quick inspection will reveal that the Sun appears slightly smaller from Mars than from Earth. This makes sense since Mars is 50% further from the Sun than Earth. More striking, perhaps, is that the Martian sunset is noticeably bluer near the Sun than the typically orange colors near the setting Sun from Earth. The reason for the blue hues from Mars is not fully understood, but thought to be related to forward scattering properties of Martian dust. The terrestrial sunset was taken in 2012 March from Marseille, France, while the Martian sunset was captured last month by NASA's robotic Curiosity rover from Gale crater on Mars.



At the Limit of Diffraction 
Image Credit & Copyright: Yuri Beletsky (Las Campanas Observatory, Carnegie Institution)
Explanation: Did you ever want to just look through the eyepiece of a large telescope in space? If you could, you would see a sharp view that was diffraction limited. Unaffected by atmospheric blurring that ultimately plagues earthbound observers, the angular resolution of your diffraction limited view would be determined only by the wavelength of light and diameter of the telescope lens or mirror; the larger the diameter, the sharper the image. Still, in this working earth-based snapshot a new active adaptive optics system (MagAO) is being used to cancel out the atmospheric blurring in a visual observation of famous double star system Alpha Centauri. Testing the system at the eyepiece of the 6.5 meter diameter Magellan Clay Telescope at Las Campanas Observatory, astronomer Laird Close is enjoying a historic diffraction limited view (inset) and the wide apparent separation of the close binary star system ... without traveling to low earth orbit.

The Sky from Mauna Kea 
Image Credit & Copyright: Shane Black Photography; Rollover Annotation: Judy Schmidt
Explanation: What if you could stand at the top of a volcano and peer out across the universe? If the timing is right, you might see an amazing panorama like the one featured here. In this case, the volcano is the Hawaii's Mauna Kea, and the time was a clear night last summer In the foreground of this south-facing panorama lies a rugged landscape dotted with rocks and hardy plants. Slightly above and further out, awhite blanket of clouds spreads horizontally to the horizon, seemingly dividing heaven and Earth. City lights illuminate the clouds and sky on the far left, while orange lava in the volcanic caldera of Kilauealights up the clouds just left of center. The summit of an even more distant Hawaiian volcano, Mauna Loa, is visible in dark silhouette near the central horizon. Green airglow is visible above the clouds, caused by air molecules excited by the Sun during the day. The Moon is the bright orb on the right. A diffuse band of light-colored zodiacal light extends up from the far right. Most distant, the dramatic central band of our Milky Way Galaxy appears to rise vertically from Mauna Loa. The person who witnessed and captured this breathtaking panorama stands before you in the image center.


Saturn at Opposition 
Image Credit & Copyright: Christopher Go
Explanation: Telescopic observers on Earth have been treated to spectacular views of Saturn lately as the ringed planet reached its 2015 opposition on May 23 at 0200 UT. Of course opposition means opposite the Sun in Earth's sky. So near opposition Saturn is up all night, at its closest and brightest for the year. These sharp images taken within hours of the Sun-Earth-Saturn alignment also show the strong brightening of Saturn's rings known as the opposition surge or the Seeliger Effect. Directly illuminated, the ring's icy particles cast no shadows and strongly backscatter sunlight toward planet Earth, creating the dramatic surge in brightness. Saturn currently stands in the sky not far from bright Antares, alpha star of the constellation Scorpius.

Auroras and Star Trails over Iceland 
Image Credit & Copyright: Vincent Brady
Explanation: It was one of the quietest nights of aurora in weeks. Even so, in northern- Iceland during last November, faint auroras lit up the sky every clear night. The featured 360-degree panorama is the digital fusion of four wide-angle cameras each simultaneously taking 101 shots over 42 minutes. In the foreground is serene Lake Myvatn dotted with picturesque rock formations left over from ancient lava flows. Low green auroras sweep across the sky above showing impressive complexity near the horizon. Stars far in the distance appear to show unusual trails -- as the Earth turned -- because early exposures wereartificially faded.

Gravitational Anomalies of Mercury 
Image Credit: NASA, GSFC's SVS, JHU's APL, Carnegie Inst. Washington
Explanation: What's that under the surface of Mercury? The robotic MESSENGER spacecraft that had been orbiting planet Mercury for the past four years had been transmitting its data back to Earth with radio waves of very precise energy. The planet's gravity, however, slightly changed this energy when measured on Earth, which enabled the reconstruction of a gravity map of unprecedented precision. Heregravitational anomalies are shown in false-color, superposed on an image of the planet's cratered surface. Red hues indicate areas of slightly higher gravity, which in turn indicates areas that must have unusually dense matter under the surface. The central area is Caloris Basin, a huge impact feature measuring about 1,500 kilometers across. Last week, after completing its mission and running low on fuel, MESSENGERwas purposely crashed onto Mercury's surface.


Astronomy News:
(from http://esciencenews.com/topics/astronomy.space)

Lopsided star explosion holds the key to other supernova mysteries

Published: Thursday, May 7, 2015 - 14:35 in Astronomy & Space

Related images
(click to enlarge)

Ott/Caltech (simulation), Drasco/Calpoly San Luis Obsipo (visualization)
Ott/Caltech (simulation), Drasco/Calpoly San Luis Obsipo (visualization)

New observations of a recently exploded star are confirming supercomputer model predictions made at Caltech that the deaths of stellar giants are lopsided affairs in which debris and the stars' cores hurtle off in opposite directions. While observing the remnant of supernova (SN) 1987A, NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, recently detected the unique energy signature of titanium-44, a radioactive version of titanium that is produced during the early stages of a particular type of star explosion, called a Type II, or core-collapse supernova.
"Titanium-44 is unstable. When it decays and turns into calcium, it emits gamma rays at a specific energy, which NuSTAR can detect," says Fiona Harrison, the Benjamin M. Rosen Professor of Physics at Caltech, and NuSTAR's principal investigator.
By analyzing direction-dependent frequency changes--or Doppler shifts--of energy from titanium-44, Harrison and her team discovered that most of the material is moving away from NuSTAR. The finding, detailed in the May 8 issue of the journal Science, is the best proof yet that the mechanism that triggers Type II supernovae is inherently lopsided.
NuSTAR recently created detailed titanium-44 maps of another supernova remnant, called Cassiopeia A, and there too it found signs of an asymmetrical explosion, although the evidence in this case is not as definitive as with 1987A.
Supernova 1987A was first detected in 1987, when light from the explosion of a blue supergiant star located 168,000 light-years away reached Earth. SN 1987A was an important event for astronomers. Not only was it the closest supernova to be detected in hundreds of years, it marked the first time that neutrinos had been detected from an astronomical source other than our sun.
These nearly massless subatomic particles had been predicted to be produced in large quantities during Type II explosions, so their detection during 1987A supported some of the fundamental theories about the inner workings of supernovae.
With the latest NuSTAR observations, 1987A is once again proving to be a useful natural laboratory for studying the mysteries of stellar death. For many years, supercomputer simulations performed at Caltech and elsewhere predicted that the cores of pending Type II supernovae change shape just before exploding, transforming from a perfectly symmetric sphere into a wobbly mass made up of turbulent plumes of extremely hot gas. In fact, models that assumed a perfectly spherical core just fizzled out.
"If you make everything just spherical, the core doesn't explode. It turns out you need asymmetries to make the star explode," Harrison says.
According to the simulations, the shape change is driven by turbulence generated by neutrinos that are absorbed within the core. "This turbulence helps push out a powerful shock wave and launch the explosion," says Christian Ott, a professor of theoretical physics at Caltech who was not involved in the NuSTAR observations.
Ott's team uses supercomputers to run three-dimensional simulations of core-collapse supernovae. Each simulation generates hundreds of terabytes of results--for comparison, the entire print collection of the U.S. Library of Congress is equal to about 10 terabytes--but represents only a few tenths of a second during a supernova explosion.
A better understanding of the asymmetrical nature of Type II supernovae, Ott says, could help solve one of the biggest mysteries surrounding stellar deaths: why some supernovae collapse into neutron stars and others into a black hole to form a space-time singularity. It could be that the high degree of asymmetry in some supernovae produces a dual effect: the star explodes in one direction, while the remainder of the star continues to collapse in all other directions.
"In this way, an explosion could happen, but eventually leave behind a black hole and not a neutron star," Ott says.
The NuSTAR findings also increase the chances that Advanced LIGO--the upgraded version of the Laser Interferometer Gravitational-wave Observatory, which will begin to take data later this year--will be successful in detecting gravitational waves from supernovae. Gravitational waves are ripples that propagate through the fabric of space-time. According to theory, Type II supernovae should emit gravitational waves, but only if the explosions are asymmetrical.
Harrison and Ott have plans to combine the observational and theoretical studies of supernova that until now have been occurring along parallel tracks at Caltech, using the NuSTAR observations to refine supercomputer simulations of supernova explosions.
"The two of us are going to work together to try to get the models to more accurately predict what we're seeing in 1987A and Cassiopeia A," Harrison says.

Source: California Institute of Technology

 

ALMA discovers proto super star cluster -- a cosmic 'dinosaur egg' about to hatch

Published: Thursday, May 7, 2015 - 12:05 in Astronomy & Space

Related images
(click to enlarge)

NASA/ESA Hubble, B. Whitmore (STScI); K. Johnson, U.Va.; ALMA (NRAO/ESO/NAOJ); B. Saxton (NRAO/AUI/NSF)

K. Johnson, U.Va.; ALMA (NRAO/ESO/NAOJ)

Globular clusters -- dazzling agglomerations of up to a million ancient stars -- are among the oldest objects in the universe. Though plentiful in and around many galaxies, newborn examples are vanishingly rare and the conditions necessary to create new ones have never been detected, until now. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered what may be the first known example of a globular cluster about to be born: an incredibly massive, extremely dense, yet star-free cloud of molecular gas.
"We may be witnessing one of the most ancient and extreme modes of star formation in the universe," said Kelsey Johnson, an astronomer at the University of Virginia in Charlottesville and lead author on a paper accepted for publication in the Astrophysical Journal. "This remarkable object looks like it was plucked straight out of the very early universe. To discover something that has all the characteristics of a globular cluster, yet has not begun making stars, is like finding a dinosaur egg that's about to hatch."
This object, which the astronomers playfully refer to as the "Firecracker," is located approximately 50 million light-years away from Earth nestled inside a famous pair of interacting galaxies (NGC 4038 and NGC 4039), which are collectively known as the Antennae galaxies. The tidal forces generated by their ongoing merger are triggering star formation on a colossal scale, much of it occurring inside dense clusters.
What makes the Firecracker unique, however, is its extraordinary mass, comparatively small size, and apparent lack of stars.
All other globular cluster analogues astronomers have observed to date are already brimming with stars. The heat and radiation from these stars have therefore altered the surrounding environment considerably, erasing any evidence of its colder, quieter beginnings.
With ALMA, the astronomers were able to find and study in detail a pristine example of such an object before stars forever change its unique characteristics. This afforded astronomers a first-ever glimpse of the conditions that may have led to the formation of many, if not all globular clusters.
"Until now, clouds with this potential have only been seen as teenagers, after star formation had begun," said Johnson. "That meant that the nursery had already been disturbed. To understand how a globular cluster forms, you need to see its true beginnings."
Most globular clusters formed during a veritable "baby boom" around 12 billion years ago, at a time when galaxies first assembled. Each contains as many as a million densely packed "second generation" stars -- stars with conspicuously low concentrations of heavy metals, indicating they formed very early in the history of the universe. Our own Milky Way is known to have at least 150 such clusters, though it may have many more.
Throughout the universe, star clusters of various sizes are still forming to this day. It's possible, though increasingly rare, that the largest and densest of these will go on to become globular clusters.
"The survival rate for a massive young star cluster to remain intact is very low -- around one percent," said Johnson. "Various external and internal forces pull these objects apart, either forming open clusters like the Pleiades or completely disintegrating to become part of a galaxy's halo."
The astronomers believe, however, that the object they observed with ALMA, which contains 50 million times the mass of the Sun in molecular gas, is sufficiently dense that it has a good chance of being one of the lucky ones.
Globular clusters evolve out of their embryonic, star-free stage very rapidly -- in as little as one million years. This means the object discovered by ALMA is undergoing a very special phase of its life, offering astronomers a unique opportunity to study a major component of the early universe.
The ALMA data also indicate that the Firecracker cloud is under extreme pressure -- approximately 10,000 times greater than typical interstellar pressures. This supports previous theories that high pressures are required to form globular clusters.
In exploring the Antennae, Johnson and her colleagues observed the faint emission from carbon monoxide molecules, which allowed them to image and characterize individual clouds of dust and gas. The lack of any appreciable thermal emission -- the telltale signal given off by gas heated by nearby stars -- confirms that this newly discovered object is still in its pristine, unaltered state.
Further studies with ALMA may reveal additional examples of proto super star clusters in the Antennae galaxies and other interacting galaxies, shedding light on the origins of these ancient objects and the role they play in galactic evolution.

Source: National Radio Astronomy Observatory

 


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.  This year's Astronomy Lecture Series will take place at A Noise Within on March 30, April 13, April 27, and May 11. Click here for more information.
2 June
AEA Astronomy Club Meeting
A DVD from our Library 

A1/1735

5 June
Friday Night 7:30PM SBAS  Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw Bl. In Torrance)
Friday Night 7:30PM Monthly General Meeting
Topic: “The Hubble Space Telescope: 25 Years of Amazing Science”
Speaker: Dr. Susan Stolovy

18 June
LAAS LAAS General Meeting.
Griffith Observatory
Event Horizon Theater
8:00 PM to 10:00 PM
June 18 & 19 The von Kármán Lecture Series: 2015

On Sea Ice

In his Nye Lecture, Doug MacAyeal provided this delightful summary of the joys of ice research: "The effectiveness of cryospheric science in addressing its main purpose (predicting and assessing response to climate change) is powerfully, but intangibly enhanced by the mysterious nature and the remote locations of ice and snow phenomena. Study of the cryosphere, in essence, depends as much on the universal human desire to satisfy curiosity as it does on the fact that cryospheric science informs humanity about the consequences of the environmental changes now clearly visible in all realms of the cryosphere." In my talk, I shall consider the study of sea ice, and shall draw on the perspective of my 25 years of involvement in this small (but growing), important corner of Earth Science. While the astonishing decline in Arctic sea ice coverage and the smaller opposing trend in the Southern Ocean have occupied the headlines, there are many processes over broad range of geophysical length scales that contribute to character of the ice cover. I will describe several of these processes that are of interest to me (ice deformation, ice growth, and snow accumulation), in particular their observation and role in polar climate.
Speaker:
Dr. Ron Kwok Senior Research Scientist, JPL
Locations:
Thursday, June 18, 2015, 7pm
The von Kármán Auditorium at JPL
4800 Oak Grove Drive
Pasadena, CA
› Directions

Friday, June 19, 2015, 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.







Observing:
The following data are from the 2015 Observer’s Handbook, and Sky & Telescope’s 2015 Skygazer’s Almanac & monthly Sky at a Glance.

Current sun & moon rise/set/phase data for L.A.:  http://www.timeanddate.com/astronomy/usa/los-angeles

Sun, Moon & Planets for April:


Moon: June 2 full, June 9 last quarter, June 16 new, June 24 1st quarter               
Planets: Jupiter & Venus  are visible in the W for a few hours after sunset.  Jupiter is up until just after midnight.  Saturn is up all night until shortly before sunrise.  Mars is hidden in the Sun’s glare all month.  Mercury is visible just before sunrise at the end of the month.
Other Events:


6 June Venus at its Greatest Eastern Elongation (45 deg)

 
6 June
SBAS Saturday Night In Town Dark Sky Observing Session at Ridgecrest Middle School– 28915 North Bay Rd. RPV, Weather Permitting: Please contact Greg Benecke to confirm that the gate will be opened! http://www.sbastro.net/

6,13,20 & 27 June
LAAS The Garvey Ranch Observatory is open to the public every Wednesday evening from 7:30 PM to 10 PM. Go into the dome to use the 8 Inch Refractor or observe through one of our telescopes on the lawn. Visit our workshop to learn how you can build your own telescope, grind your own mirror,  or sign up for our free seasonal astronomy classes.

Call 213-673-7355 for further information.
Time: 7:30 PM - 10:00 PM
Location: Garvey Ranch Obs. , 781 Orange Ave., Monterey Park, CA 91755


13 June
SBAS out-of-town Dark Sky observing – contact Greg Benecke http://www.sbastro.net/.  

15 June Mercury 0.04deg N of Moon, occultation

21 June Solstice

24 June Mercury greatest elongation W (22deg)

30 June Venus and Jupiter within 0.3 deg

30 June
Public  Star Party: Griffith Observatory Grounds 2-10pm


Internet Links:

Telescope, Binocular & Accessory Buying Guides


General


Regional (Southern California, Washington, D.C. & Colorado)
Southern California & Beyond Amateur Astronomy Organizations, Observatories & Planetaria
Mt. Wilson Observatory description, history, visiting


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, membership in The Astronomical League, 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, President & 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 
Posted by at No comments:
Subscribe to: Posts (Atom)