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)

Wednesday, December 14, 2016

2016 December

AEA Astronomy Club Newsletter December 2016

Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 1
Astronomy News p. 6
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:

1 Dec
AEA Astronomy Club Meeting
Mt. Wilson Observatory DVD
(A1/1735)

5 Jan
AEA Astronomy Club Meeting
Pizza Party & Online Astronomy
(A1/1735)
AEA Astronomy Club meetings are now on 1st  Thursdays at 11:45 am.  For all of 2016, the meeting room is A1/1735. 


Club News:  

Mark Clayson was re-elected president of the club, and Alan Olson was re-elected treasurer.  Any help from others will be greatly appreciated, including finding club speakers, help with STEM or other events – see Mark Clayson for any of those.  And help planning use of club equipment in the Aug. 21 total solar eclipse – see David P. Taylor and Kirk Crawford to volunteer for that.

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

VIDEO:  ISS Fisheye Fly-Through https://apod.nasa.gov/apod/ap161105.html
Image Credit: NASA, ISS, Harmonic
Explanation: Shot in Ultra HD, this stunning video can take you on a tour of the International Space Station. A fisheye lens with sharp focus and extreme depth of field provides an immersive visual experience of life in the orbital outpost. In the 18 minute fly-through, your point of view will float serenely while you watch our fair planet go by 400 kilometers below the seven-windowed Cupola, and explore the interior of the station's habitable nodes and modules from an astronaut's perspective. The modular International Space Station is Earth's largest artificial satellite, about the size of a football field in overall length and width. Its total pressurized volume is approximately equal to that of a Boeing 747 aircraft.
Arp 299: Black Holes in Colliding Galaxies 
Image Credit: NASA, JPL-Caltech, GSFC, Hubble, NuSTAR
Explanation: Is only one black hole spewing high energy radiation -- or two? To help find out, astronomers trained NASA's Earth-orbiting NuSTAR and Chandra telescopes on Arp 299, the enigmatic colliding galaxies expelling the radiation. The two galaxies of Arp 299 have been locked in a gravitational combat for millions of years, while their central black holes will soon do battle themselves. Featured, the high-resolution visible-light image was taken by Hubble, while the superposed diffuse glow of X-ray light was imaged by NuSTAR and shown in false-color red, green, and blue. NuSTAR observations show that only one of the central black holes is seen fighting its way through a region of gas and dust -- and so absorbing matter and emitting X-rays. The energetic radiation, coming only from the galaxy center on the right, is surely created nearby -- but outside -- the central black hole's event horizon. In a billion years or so, only one composite galaxy will remain, and only one central supermassive black hole. Soon thereafter, though, another galaxy may enter the fray.

Soyuz vs Supermoon 
Image Credit: NASA, Bill Ingalls
Explanation: Faster than a speeding bullet, more powerful than a locomotive, and able to leap tall buildings in a single bound, this Soyuz rocket stands on the launch pad at Baikonur Cosmodrome in Kazakhstan on November 14.Beyond it rises a supermoon, but fame for exceptional feats of speed, strength, and agility is not the reason November's Full Moon was given this popular name. Instead, whenever a Full Moon shines near perigee, the closest point in its elliptical orbit around Earth, it appears larger and brighter than other more distant Full Moons, and so a supermoon is born. In fact, November's supermoon was the second of three consecutive supermoons in 2016. It was also the closest and most superest Full Moon since 1948. Meanwhile, the mild mannered Soyuz rocket is scheduled to launch its Expedition 50/51 crew to the International Space Station today, November 17.
Cold Weather Delayed over North America 
Image Credit: Climate Reanalyzer, CCI, U. Maine
Explanation: Why is it so warm in northern North America? Usually during this time of year -- mid-November -- temperatures average as much as 30 degrees colder. Europe is not seeing a similar warming. One factor appears to be an unusually large and stable high pressure region that has formed over Canada, keeping normally colder arctic air away. Although the fundamental cause of any weather pattern is typically complex, speculation holds that this persistent Canadian anticyclonic region is related to warmer than average sea surface temperatures in the mid-Pacific -- an El Niño -- operating last winter. North Americans should enjoy it while it lasts, though. In the next week or two, cooler-than-average temperatures now being recorded in the mid-Pacific -- a La Niña -- might well begin to affect North American wind and temperature patterns.


Pluto's Sputnik Planum 
Image Credit: NASA, Johns Hopkins U./APL, Southwest Research Inst.
Explanation: Is there an ocean below Sputnik Planum on Pluto? The unusually smooth 1000-km wide golden expanse, visible in the featured image from New Horizons, appears segmented into convection cells. But how was this region created? One hypothesis now holds the answer to be a great impact that stirred up an underground ocean of salt water roughly 100-kilometers thick. The featured image of Sputnik Planum, part of the larger heart-shapedTombaugh Regio, was taken last July and shows true details in exaggerated colors. Although the robotic New Horizons spacecraft is off on a new adventure, continued computer-modeling of this surprising surface feature on Plutois likely to lead to more refined speculations about what lies beneath.


Nova over Thailand 
Image Credit & Copyright: Jeff Dai (TWAN)
Explanation: A nova in Sagittarius is bright enough to see with binoculars. Discovered last month by the All-Sky Automated Survey for Supernovae (ASAS-SN), the stellar explosion even approached the limit of naked-eye visibility last week. A classical nova results from a thermonuclear explosion on the surface of a white dwarf star -- a dense star having the size of our Earth but the mass of our Sun. In the featured image, the nova was captured last week above ancient Wat Mahathat in Sukhothai, Thailand. To see Nova Sagittarius 2016 yourself, just go out just after sunset and locate near the western horizon the constellation of the Archer (Sagittarius), popularly identified with an iconic teapot. Also visible near the nova is the very bright planet Venus. Don’t delay, though, because not only is the nova fading, but that part of the sky is setting continually closer to sunset.




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

Astronomers observe star reborn in a flash

Published: Tuesday, September 13, 2016 - 19:01 in Astronomy & Space

Related images


ESA/Hubble & NASA
An international team of astronomers using Hubble have been able to study stellar evolution in real time. Over a period of 30 years dramatic increases in the temperature of the star SAO 244567 have been observed. Now the star is cooling again, having been reborn into an earlier phase of stellar evolution. This makes it the first reborn star to have been observed during both the heating and cooling stages of rebirth. Even though the Universe is constantly changing, most processes are too slow to be observed within a human lifespan. But now an international team of astronomers have observed an exception to this rule. "SAO 244567 is one of the rare examples of a star that allows us to witness stellar evolution in real time", explains Nicole Reindl from the University of Leicester, UK, lead author of the study. "Over only twenty years the star has doubled its temperature and it was possible to watch the star ionising its previously ejected envelope, which is now known as the Stingray Nebula."
SAO 244567, 2700 light-years from Earth, is the central star of the Stingray Nebula and has been visibly evolving between observations made over the last 45 years. Between 1971 and 2002 the surface temperature of the star skyrocketed by almost 40 000 degrees Celsius. Now new observations made with the Cosmic Origins Spectrograph (COS) on the NASA/ESA Hubble Space Telescope have revealed that SAO 244567 has started to cool and expand.
This is unusual, though not unheard-of [1], and the rapid heating could easily be explained if one assumed that SAO 244567 had an initial mass of 3 to 4 times the mass of the Sun. However, the data show that SAO 244567 must have had an original mass similar to that of our Sun. Such low-mass stars usually evolve on much longer timescales, so the rapid heating has been a mystery for decades.
Back in 2014 Reindl and her team proposed a theory that resolved the issue of both SAO 244567's rapid increase in temperature as well as the low mass of the star. They suggested that the heating was due to what is known as a helium-shell flash event: a brief ignition of helium outside the stellar core [2].
This theory has very clear implications for SAO 244567's future: if it has indeed experienced such a flash, then this would force the central star to begin to expand and cool again -- it would return back to the previous phase of its evolution. This is exactly what the new observations confirmed. As Reindl explains: "The release of nuclear energy by the flash forces the already very compact star to expand back to giant dimensions -- the born-again scenario."
It is not the only example of such a star, but it is the first time ever that a star has been observed during both the heating and cooling stages of such a transformation.
Yet no current stellar evolutionary models can fully explain SAO 244567's behaviour. As Reindl elaborates: "We need refined calculations to explain some still mysterious details in the behaviour of SAO 244567. These could not only help us to better understand the star itself but could also provide a deeper insight in the evolution of central stars of planetary nebulae."
Until astronomers develop more refined models for the life cycles of stars, aspects of SAO 244567's evolution will remain a mystery.

Source: ESA/Hubble Information Centre


The supernova that wasn't: A tale of 3 cosmic eruptions

Published: Saturday, September 3, 2016 - 05:07 in Astronomy & Space

Related images

 Nathan Smith/UA and NASA
 Kiminki et al./NASA

Kiminki et al./NASA

1800s, astronomers surveying the night sky in the Southern Hemisphere noticed something strange: Over the course of a few years, a previously inconspicuous star named Eta Carinae grew brighter and brighter, eventually outshining all other stars except Sirius, before fading again over the next decade, becoming too dim to be seen with the naked eye. What had happened to cause this outburst? Did 19th-century astronomers witness some strange type of supernova, a star ending its life in a cataclysmic explosion?
"Not quite," says Megan Kiminki, a doctoral student in the University of Arizona's Department of Astronomy and Steward Observatory. "Eta Carinae is what we call a supernova impostor. The star became very bright as it blew off a lot of material, but it was still there."
Indeed, in the mid-20th century Eta Carinae began to brighten again.
The aftermath of the "Great Eruption" of the mid-1800s, which is now readily visible through a small telescope if you happen to be in the Southern Hemisphere, made Eta Carinae a celebrity among objects in the universe known for their bizarre beauty. An hourglass-shaped, billowing cloud of glowing gas and dust enshrouds the star and its companion. Known as the Homunculus nebula, the cloud consists of stellar material hurled into space during the Great Eruption, drifting away at 2 million miles per hour.
By carefully analyzing images of Eta Carinae taken with NASA's Hubble Space Telescope, Kiminki and her team were surprised to discover that the Great Eruption was only the latest in a series of massive outbursts launched by the star system since the 13th century. Published in the journal Monthly Notices of the Royal Astronomical Society, the paper was co-authored by Nathan Smith, associate professor in the UA's Department of Astronomy, and Megan Reiter, who obtained her Ph.D. from the same department last year and is now a postdoctoral fellow at the University of Michigan.
The expansion rate of gas that was far outside the Homunculus indicated that it was moving slowly and must have been ejected centuries before the observed 19th-century brightening. In fact, the motions of the outer material point to two separate eruptions in the mid-13th and mid-16th centuries.
For scientists trying to piece together what makes star systems such as Eta Carinae tick, the findings are like the stereotypical smoking gun in a detective story.
"From the first reports of its 19th-century outburst up to the most recent data obtained with advanced capabilities on modern telescopes, Eta Carinae continues to baffle us," Smith says. "The most important unsolved problem has always been the underlying cause of its eruption, and now we find that there were multiple previous eruptions. This is a bit like reconstructing the eruption history of a volcano by discovering ancient lava flows."
Although the glowing gases of the Homunculus nebula prevent astronomers from getting a clear look at what's inside, they have figured out that Eta Carinae is a binary system of two very massive stars that orbit each other every 5.5 years. Both are much bigger than our sun and at least one of them is nearing the end of its life.
"These are very large stars that appear very volatile, even when they're not blowing off nebulae," Kiminki says. "They have a dense core and very fluffy envelopes. If you replaced our sun by the larger of the two, which has about 90-100 solar masses, it could very well extend into the orbit of Mars."
Because the Homunculus nebula is such an iconic and visually stunning object, it has been a popular target of astronomical observations. A total of eight images, taken over the course of two decades with Hubble, turned out to be a treasure trove for Kiminki and her co-authors.
The original goal of the team's observing program was to measure proper motions of stars and protostellar jets -- fast streams of matter ejected by young stars during formation -- in the Carina Nebula, but the same data also provided a powerful way to measure the motion of debris ejected by Eta Carinae itself.
"As I was aligning the images, I noticed that the one that Eta Carinae in it was more difficult to align," Kiminki says. "We can only use objects as alignment points that aren't moving, and I thought, 'Wow, a lot of this stuff is really moving.' And then we decided to take a closer look."
By aligning the multi-epoch images of the nebula, the team was able to track the movement of more than 800 blobs of gas Eta Carinae had ejected over time and derived a likely ejection date for each. The analyses showed that the Homunculus nebula and the observed 19th-century brightening tell only part of the story. Measuring the speed with which wisps of ejected material expand outward into space revealed that they must have resulted from two separate eruptions that occurred about 600 and 300 years before the Great Eruption of the 19th century.
In addition to having a separate origin in time, the older material also showed a very different geometry from the Homunculus, where material was ejected out from the star's poles and appears symmetric about its rotation axis.
"We found one of the prior eruptions was similarly symmetric, but at a totally different angle from the axis of the Great Eruption," Kiminki explains. "Even more surprising was that the oldest eruption was very one-sided, suggesting two stars were involved, because it would be very unlikely for one star to blow material out toward just one side."
Though perplexing, the findings are a big step forward for astronomers trying to understand what causes the frequent outbursts.
"We don't really know what's going on with Eta Carinae," Kiminki says. "But knowing that Eta Carinae erupted at least three times tells us that whatever causes those eruptions must be a recurring process, because it wouldn't be very likely that each eruption is caused by a different mechanism."
"Even though we still have not figured out the underlying physical mechanism that caused the 19th-century eruption, we now know that it isn't a one-time event," Smith says. "That makes it harder to understand, but it is also a critical piece of the puzzle of how very massive stars die. Stars like Eta Carinae apparently refuse to go quietly into the night."
Eta Carinae's eruptions provide unique insights into the last unstable phases of a very massive star's life. Researchers who study supernovae have identified a subclass of supernova explosions that appear to suffer violent eruptions shortly before they finally explode. Smith notes that Eta Carinae might be our nearest example of this.
Because it takes light 7,000 years to travel from Eta Carinae to Earth, much could have happened in the meantime, Kiminki says. "Eta Carinae may have gone supernova by now, and we wouldn't know until 7,000 years from now."

Source: University of Arizona



 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.  . Click here for more information.
1 Dec
AEA Astronomy Club Meeting
Mt. Wilson Observatory DVD
(A1/1735)






2 Dec
Friday Night 7:30PM SBAS  Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw Bl. In Torrance)
Topic:  “The Planet…VULCAN?! (The real one…sorta)” David Nakamoto, LAAS

10 Dec
LAAS LAAS General Meeting.
Griffith Observatory
Event Horizon Theater
8:00 PM to 10:00 PM

December 15 & 16 The von Kármán Lecture Series: 2016
Spinning Black Holes, Exploding Stars, and Hyperluminous Pulsars: Recent Results from the NuSTAR Satellite
NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, launched in June 2012 and became the first telescope in orbit to focus high energy X-ray light. This powerful X-ray emission provides a unique probe of the most energetic phenomena in the universe, from flares on the surface of the Sun, to the explosions of stars, to the extreme environments around neutron stars and black holes. The crisp, sensitive images enabled by NuSTAR's new technology have dramatically changed our picture of the extreme universe. This talk will present some of the highlights from the first four years of NuSTAR observations, including the surprising discovery of a new class of hyperluminous neutron stars, measurements of how fast black holes spin, and unique insight into the physics of supernova explosions.
Speaker:
Dr. Daniel K. Stern, NuSTAR Project Scientist, JPL

Webcast:
Click here to watch the event live on Ustream (or archived after the event)
Locations:
Thursday, Dec 15, 2016, 7pm
The von Kármán Auditorium at JPL
4800 Oak Grove Drive
Pasadena, CA
› Directions

Friday, Dec 16, 2016, 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.



5 Jan
AEA Astronomy Club Meeting
Pizza Party & Online Astronomy
(A1/1735)
13 January

SBAS Friday Evening  7:30 PM Monthly General Meeting
Topic:   TBD Speaker: TBD

22 Jan. Emeritus Prof. Bruce Runnegar

The Cryogenian, coldest time in Earth History

Location: UCLA, Slichter 3853
Time: 2:30PM
We are now in (and probably leaving) one of the coldest periods in Earth history. Previous icehouse intervals occurred about 300, 700 and 2000 million years ago. During one of these periods, the Cryogenian, glacial ice extended to sea level in the tropics. We shall discuss this so-called Snowball Earth event in terms of its origin, and its effects on our planet and its life. Image credit: Chris Butler/SPL

Observing:

The following data are from the 2016 Observer’s Handbook, and Sky & Telescope’s 2016 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 December:

  

Moon: Dec 7 1st quarter, Dec 14 full, Dec 21 last quarter, Dec 29 new                 
Planets: Mercury, Venus& Mars are up for 1-3 hours after sunset.   Jupiter & Saturn are visible for 1-3 hours before sunrise (Saturn only beginning Dec. 27).
Other Events:


10 Dec
LAAS Public  Star Party: Griffith Observatory Grounds 2-10pm


7,14,21,28 Dec
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

11 December Mercury at Greatest Eastern Elongation Easiest time to see tiny Mercury after sunset.

12 December Moon Occults Aldebaran Watch bright Aldebaran disappear behind the moon at 7:00 PM PST and then reappear at 8:05.

13 December Geminids Meteor Shower Peak Normally a good meteor shower with 120-160 meteors/hour.  The full moon will limit observing to the brightest meteors.

22 December Ursids Meteor Shower Peak The Ursids come from a very narrow stream of comet debris.  One has to be within 12 hours of the peak to seem much. During a good outburst rates of 160/hour can be seen.

 
24 Dec
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/


31 Dec
SBAS out-of-town Dark Sky observing – contact Greg Benecke to coordinate a location. http://www.sbastro.net/.  



LAAS Private dark sky  Star Party


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 
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