AEA Astronomy Club
Newsletter December 2014
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. 11
Useful Links p. 13
About the Club p. 13
Club News & Calendar.
Calendar
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. 11
Useful Links p. 13
About the Club p. 13
Club News & Calendar.
Calendar
Club Meeting Schedule:
18 Dec
|
Club Meeting
|
“Doing real science with club equipment... and you
can too!"
|
Jim
Edwards
|
A1/1735
|
AEA Astronomy Club meetings are on 3rd Thursdays at 11:45am. For all of 2014 except May & Nov., the meeting room is A1/1735.
News:
We’ve
received a $4,000 budget allotment from the AEA. We can
now look into scheduling a night on the Mt. Wilson 60-inch or 100-inch. And any acquisitions, such as an astrograph.
Astronomy Video(s)
& Picture(s) of the Month
(from
Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html)
Video: Soaring over Titan http://apod.nasa.gov/apod/ap141124.html
Video Credit: Cassini Radar Mapper, JPL, USGS, ESA, NASA
Explanation: What would
it look like to fly over Titan? Radar images from NASA's robotic Cassini satellite in orbit around Saturn have been digitally compiled to simulate such a flight. Cassini has swooped
past Saturn's cloudiest moon several times since it arrived at the ringed
planet in 2004. The virtual flight featured here shows numerous lakes colored black and mountainous terrain
colored tan. Surface regions without detailed vertical information
appear more flat, while sufficiently mapped regions have their heights
digitally stretched. Among the basins visualized is Kraken Mare, Titan's largest lake which spans
over 1,000 kilometers long. Titan's lakes are different from Earth's lakes in that they
are composed of hydrocarbons with similarities to liquid natural gas. How Titan's lakes were created and why they survive continues to
be a topic of research.Video Credit: Cassini Radar Mapper, JPL, USGS, ESA, NASA
Star
Formation in the Tadpole Nebula
Image Credit: WISE, IRSA, NASA; Processing & Copyright : Francesco Antonucci
Explanation: Dusty
emission in the Tadpole nebula, IC 410, lies about 12,000 light-years away in
the northern constellation Auriga. The cloud of glowing gas is over
100 light-years across, sculpted by stellar winds and radiation from embedded open star cluster NGC 1893. Formed in the interstellar cloud a mere 4 million years ago, bright cluster stars are
seen all around the star-forming nebula. Notable near the image center are two
relatively dense streamers of material trailing away from the nebula's central
regions. Potentially sites of ongoing star formation in IC 410, these cosmic tadpole shapes are about 10 light-years long. The featured image was taken in infrared light by NASA's Wide Field Infrared Survey Explorer (WISE) satellite.Image Credit: WISE, IRSA, NASA; Processing & Copyright : Francesco Antonucci
Solar Flare
from a Sharper Sun
Image Credit: Solar Dynamics Observatory/AIA, NASA
Processing: NAFE by Miloslav Druckmuller (Brno University of Technology)
Explanation: Solar active region
AR2192 was the
largest recorded sunspot group of the last 24 years. Before rotating off the Earth-facing side of the Sun at the end of October, it produced a whopping six energetic X-class flares. Its most intense
flare was captured on October 24 in this stunning view from the orbiting Solar Dynamics Observatory. The scene
is a color combination of images made at three different wavelengths
of extreme ultraviolet light; 193 angstroms shown in blue, 171 angstroms in
white, and 304 angstroms in red. The emission, from highly ionized Iron and
Helium atoms, traces magnetic field lines looping through the hot plasma of the Sun's outer chromosphere and corona. Beneath, the cooler solar
photosphere appears dark at extreme ultraviolet wavelengths. The exceptionally
sharp composite image has been processed with a new mathematical algorithm (NAFE) that
adapts to noise and brightness in extreme ultraviolet image data to reliably
enhance small details.Image Credit: Solar Dynamics Observatory/AIA, NASA
Processing: NAFE by Miloslav Druckmuller (Brno University of Technology)
Astronomy
News:
Finding infant
earths and potential life just got easier
Among the billions and billions of stars in the sky,
where should astronomers look for infant Earths where life might develop? New
research from Cornell University's Institute for Pale Blue Dots shows where --
and when -- infant Earths are most likely to be found. The paper by research
associate Ramses M. Ramirez and director Lisa Kaltenegger, "The Habitable
Zones of Pre-Main-Sequence Stars" will be published in the Jan. 1, 2015,
issue of Astrophysical Journal
Letters."The search for new, habitable worlds is one of the most exciting things human beings are doing today and finding infant Earths will add another fascinating piece to the puzzle of how 'Pale Blue Dots' work" says Kaltenegger, associate professor of astronomy in Cornell's College of Arts and Sciences.
The researchers found that on young worlds the Habitable Zone -- the orbital region where water can be liquid on the surface of a planet and where signals of life in the atmosphere can be detected with telescopes -- turns out to be located further away from the young stars these worlds orbit than previously thought.
"This increased distance from their stars means these infant planets should be able to be seen early on by the next generation of ground-based telescopes," says Ramirez. "They are easier to spot when the Habitable Zone is farther out, so we can catch them when their star is really young."
Moreover, say the researchers, since the pre-main sequence period for the coolest stars is long, up to 2.5 billion years, it's possible that life could begin on a planet during its sun's early phase and then that life could move to the planet's subsurface (or underwater) as the star's luminosity decreases.
"In the search for planets like ours out there, we are certainly in for surprises. That's what makes this search so exciting," says Kaltenegger.
To enable researchers to more easily find infant earths, the paper by Kaltenegger and Ramirez offers estimates for where one can find habitable infant Earths. As reference points, they also assess the maximum water loss for rocky planets that are at equivalent distances to Venus, Earth and Mars from our Sun.
Ramirez and Kaltenegger also found that during the early period of a solar system's development, planets that end up being in the Habitable Zone later on, when the star is older, initially can lose the equivalent of several hundred oceans of water or more if they orbit the coolest stars. However, even if a runaway greenhouse effect is triggered -- when a planet absorbs more energy from the star than it can radiate back to space, resulting in a rapid evaporation of surface water -- a planet could still become habitable if water is later delivered to the planet, after the runaway phase ends.
"Our own planet gained additional water after this early runaway phase from a late, heavy bombardment of water-rich asteroids," says Ramirez. "Planets at a distance corresponding to modern Earth or Venus orbiting these cool stars could be similarly replenished later on."
Source: Cornell University
Strange galaxy perplexes
astronomers
With the help of citizen scientists, a team of
astronomers has found an important new example of a very rare type of galaxy
that may yield valuable insight on how galaxies developed in the early
Universe. The new discovery technique promises to give astronomers many more
examples of this important and mysterious type of galaxy. The galaxy they
studied, named J1649+2635, nearly 800 million light-years from Earth, is a
spiral galaxy, like our own Milky Way, but with prominent "jets" of
subatomic particles propelled outward from its core at nearly the speed of
light. The problem is that spiral galaxies are not supposed to have such large
jets."The conventional wisdom is that such jets come only from elliptical galaxies that formed through the merger of spirals. We don't know how spirals can have these large jets," said Minnie Mao, of the National Radio Astronomy Observatory (NRAO).
J1649+2635 is only the fourth jet-emitting spiral galaxy discovered so far. The first was found in 2003, when astronomers combined a radio-telescope image from the Karl G. Jansky Very Large Array (VLA) and a visible-light image of the same object from the Hubble Space Telescope. The second was revealed in 2011 by images from the Sloan Digital Sky Survey and the VLA, and the third, found earlier this year, also was discovered by combining radio and visible-light images.
"In order to figure out how these jets can be produced by the 'wrong' kind of galaxy, we realized we needed to find more of them," Mao said.
To do that, the astronomers looked for help. That help came in the form of large collections of images from both radio and optical telescopes, and the hands-on assistance of volunteer citizen scientists. The volunteers are participants in an online project called the Galaxy Zoo, in which they look at images from the visible-light Sloan Digital Sky Survey and classify the galaxies as spiral, elliptical, or other types. Each galaxy image is inspected by multiple volunteers to ensure accuracy in the classification.
So far, more than 150,000 Galaxy Zoo participants have classified some 700,000 galaxies. Mao and her collaborators used a "superclean" subset of more than 65,000 galaxies, for which 95 percent of those viewing each galaxy's image agreed on the classification. About 35,000 of those are spiral galaxies. J1649+2635 had been classified by 31 Galaxy Zoo volunteers, 30 of whom agreed that it is a spiral.
Next, the astronomers decided to cross-match the visible-light spirals with galaxies in a catalog that combines data from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty Centimeters survey, both done using the VLA. This job was done by Ryan Duffin, a University of Virginia undergraduate working as an NRAO summer student. Duffin's cross-matching showed that J1649+2635 is both a spiral galaxy and has powerful twin radio jets.
"This is the first time that a galaxy was first identified as a spiral, then subsequently found to have large radio jets," Duffin said. "It was exciting to make such a rare find," he added.
Jets such as those seen coming from J1649+2635 are propelled by the gravitational energy of a supermassive black hole at the core of the galaxy. Material pulled toward the black hole forms a rapidly-rotating disk, and particles are accelerated outward along the poles of the disk. The collision that presumably forms an elliptical galaxy disrupts gas in the merging galaxies and provides "fuel" for the disk and acceleration mechanism. That same disruption, however, is expected to destroy any spiral structure as the galaxies merge into one.
J1649+2635 is unusual not only because of its jets, but also because it is the first example of a "grand design" spiral galaxy with a large "halo" of visible-light emission surrounding it.
"This galaxy presents us with many mysteries. We want to know how it became such a strange beast," Mao said. "Did it have a unique type of merger that preserved its spiral structure? Was it an elliptical that had another collision that made it re-grow spiral arms? Is its unique character the result of interaction with its environment?"
"We will study it further, but in addition, we need to see if there are more like it," Mao said.
"We hope that with projects like the Galaxy Zoo and another called Radio Galaxy Zoo, those thousands of citizen scientists can help us find many more galaxies like this one so we can answer all our questions," Mao said. Mao and her colleagues have dubbed these rare galaxies "Spiral DRAGNs," an acronym for the technical description, "Double-lobed Radio sources Associated with Galactic Nuclei."
Mao and Duffin worked with Frazer Owen, Emmanuel Momjian, and Mark Lacy, also of the NRAO; Bill Keel of the University of Alabama; Glenn Morrison of the University of Hawaii and the Canada-France-Hawaii Telescope; Tony Mroczkowski of the Naval Research Laboratory; Susan Neff of NASA's Goddard Space Flight Center; Ray Norris of CSIRO Astronomy and Space Science in Australia; Henrique Schmitt of the Naval Research Laboratory; and Vicki Toy and Sylvain Veilleux of the University of Maryland. The scientists are reporting their findings in the Monthly Notices of the Royal Astronomical Society.
The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Source: National Radio Astronomy Observatory
General
Calendar:
Colloquia, Lectures, Seminars, Meetings, Open Houses & Tours:
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/
5
Dec
|
Friday Night 7:30PM SBAS Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw
Bl. In Torrance)
Topic: “Edward Emerson Barnard: The World’s Greatest Observer of His
Time, 19th Century Astronomer and Astrophotography Pioneer”
Matthew Ota, Telescopes in Education Foundation
|
8 Dec.
|
LAAS
LAAS General Meeting.
|
Griffith
Observatory
Event Horizon Theater 8:00 PM to 10:00 PM |
Dec. 4 & 5 The von Kármán Lecture Series: 2014
Lecture: NASA’s Dawn Mission to the
Asteroid Belt
The ambitious and exciting Dawn mission is one of NASA's most
remarkable ventures into the solar system. After more than seven years of
interplanetary spaceflight, the probe is just a few months away from the
mysterious world Ceres. The spacecraft has already completed a spectacular
exploration of Vesta. These were among the last uncharted worlds in the inner
solar system prior to Dawn. They are the two most massive residents of the main
asteroid belt, that vast collection of bodies between Mars and Jupiter. Ceres
is so large that it is included in the category of dwarf planets, along with
Pluto. The alien landscapes Dawn reveals provide humankind with a new
perspective on the solar system. Remnants from the time that planets were
formed, Ceres and Vesta hold clues that will help scientists understand the
dawn of the solar system. Dawn orbited Vesta from July 2011 to September 2012
and returned astonishing views of this fascinating world. It is the only
spaceship ever to orbit an object in the asteroid belt and is the first ever
targeted to orbit any two extraterrestrial destinations. Such a mission would
be truly impossible without the use of ion propulsion, a technology that has
mostly been in the domain of science fiction. Dr. Marc Rayman will give a fascinating
and entertaining presentation on the Dawn mission and its two exotic
destinations as well as its use of ion propulsion. He also will share the
excitement and profundity of controlling a robotic ambassador from Earth in
deep space.
Speaker:
Dr. Marc Rayman, Dawn Project Mission Director
Dr. Marc Rayman, Dawn Project Mission Director
Locations:
|
Thursday, Dec 4, 2014, 7pm
The von Kármán Auditorium at JPL 4800 Oak Grove Drive Pasadena, CA › Directions Friday, Dec 5, 2014, 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. |
|
18 Dec
|
AEA Astronomy
Club Meeting
|
“Doing real science with club equipment... and you
can too!"
|
Jim
Edwards
|
A1/1735
|
Observing:
The
following data are from the 2014 Observer’s Handbook, and Sky & Telescope’s
2014 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
A weekly 5 minute video about what’s up in the night
sky: www.skyandtelescope.com/skyweek.
Sun,
Moon & Planets for December:
Moon: Dec 6 full, Dec 14
last quarter, Dec 22 new, Dec 28 1st quarter
Planets:
Mercury, Venus & Mars are visible in the SW briefly after sunset. Jupiter
rises late evening in the east. Saturn is visible in the E in the
morning just before sunrise.
Other
Events:
13 December Geminids Meteor Shower Peak
This meteor shower gets the
name "Geminids" because it appears to radiate from the constellation
Gemini. An observer in the
Northern Hemisphere can start seeing Geminid meteors as early as
December 6, when one meteor
every hour or so could be visible. During the next week, rates
increase until a peak of 50-80
meteors per hour is attained on the night of December 13/14. The
last Geminids are seen on
December 18, when an observer might see a rate of one every hour or
so.
13 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/
|
19 Dec Saturn 1.5deg S. of the Moon
20
Dec
|
LAAS Dark Sky Night : Lockwood Valley (Steve Kufeld Astronomical Site; LAAS members and their guests only)
|
20 Dec
|
SBAS
out-of-town Dark Sky observing – contact Greg Benecke http://www.sbastro.net/.
|
21 Winter Solstice
22 December Ursid Meteor Shower Peak
The point from where the Ursid
meteors appear to come from is located within the constellation
Ursa Minor, also known as the
"Little Dipper". This meteor shower is active during the period
spanning December 17 to 25, but
it peaks on December 22/23. At maximum, rates can normally
reach 10 per hour. The meteor
shower is produced by the periodic comet 8P/Tuttle and can
occasionally experience
short-lived outbursts of up to 100 meteors per hour.
27 Dec
|
Public Star Party: Griffith Observatory Grounds 2-10pm
|
29 Dec Uranus 1.0
deg S of the Moon, occultation
Internet
Links:
Telescope, Binocular & Accessory Buying
Guides
General
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/.
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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