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, September 13, 2019

2019 September


AEA Astronomy Club Newsletter                         September 2019

Contents

AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 2
Astronomy News p. 6
General Calendar p. 8
    Colloquia, lectures, mtgs. p. 8
    Observing p. 11
Useful Links p. 12
About the Club p. 13

Club News & Calendar.

Club Calendar

Club Meeting Schedule: -- note the possible change of date in Sept. due to Labor Day holiday week


12 Sept.
AEA Astronomy Club Meeting
Demo of Meade GoTo Scope & Another Lecture from “The Remarkable Science of Ancient Astronomy,” Prof. Bradley Schaefer?
(A1/1735)

3 Oct.
AEA Astronomy Club Meeting
Pizza Party & ?
(A1/1735)
4 Oct. – Dana Middle School star party 6:30-8:30pm

5 Oct. – Club Mt. Wilson night (booked full)

AEA Astronomy Club meetings are now on 1st  Thursdays at 11:45 am.  For 2018:  Jan. 4 in A1/1029 A/B, Feb. 1 & March 1 in A1/2906 and for the rest of 2018 (April-Dec), the meeting room is A1/1735. 

Club News:  

We need volunteers to help with: 

·         Populating our club Sharepoint site with material & links to the club’s Aerowiki & Aerolink materials – Kaly Rangarajan has volunteered to help with this
·         Arranging future club programs
·         Managing club equipment & library (Kelly Gov volunteered to help with the library)

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


Supernova Cannon Expels Pulsar J0002 
Image Credit: F. Schinzel et al. (NRAO, NSF), Canadian Galactic Plane Survey (DRAO), NASA (IRAS); Composition: Jayanne English (U. Manitoba)
Explanation: What could shoot out a neutron star like a cannon ball? A supernova. About 10,000 years ago, the supernova that created the nebular remnant CTB 1 not only destroyed a massive star but blasted its newly formed neutron star core -- a pulsar -- out into the Milky Way Galaxy. The pulsar, spinning 8.7 times a second, was discovered using downloadable software Einstein@Home searching through data taken by NASA's orbiting Fermi Gamma-Ray Observatory. Traveling over 1,000 kilometers per second, the pulsar PSR J0002+6216 (J0002 for short) has already left the supernova remnant CTB 1, and is even fast enough to leave our Galaxy. Pictured, the trail of the pulsar is visible extending to the lower left of the supernova remnant. The featured image is a combination of radio images from the VLA and DRAO radio observatories, as well as data archived from NASA's orbiting IRAS infrared observatory. It is well known that supernovas can act as cannons, and even that pulsars can act as cannonballs -- what is not known is how supernovas do it.
The Local Void in the Nearby Universe 
Image Credit: R. Brent Tully (U. Hawaii) et al.
Explanation: What does our region of the Universe look like? Since galaxies are so spread out over the sky, and since our Milky Way Galaxy blocks part of the distant sky, it has been hard to tell. A new map has been made, however, using large-scale galaxy motions to infer what massive objects must be gravitating in the nearby universe. The featured map, spanning over 600 million light years on a side, shows that our Milky Way Galaxy is on the edge of the Virgo Cluster of Galaxies, which is connected to theGreat Attractor -- an even larger grouping of galaxies. Also nearby are the massive Coma Cluster and the extensive Perseus-Pisces Supercluster. Conversely, we are also on the edge of huge region nearly empty of galaxies known as the Local Void. The repulsive push by the Local Void combined with the gravitational pull toward the elevated galaxy density on the other side of the sky explains part of the mysteriously high speed our Galaxy has relative to the cosmic microwave background -- but not all. To explore the local universe yourself, as determined by Cosmicflows-3, you are invited to zoom in and spin around this interactive 3D visualization.
Arp 87: Merging Galaxies from Hubble 
Image Credit: NASA, ESA, Hubble Heritage Team (STScI, AURA)
Explanation: This dance is to the death. Along the way, as these two large galaxies duel, a cosmic bridge of stars, gas, and dust currently stretches over 75,000 light-years and joins them. The bridge itself is strong evidence that these two immense star systems have passed close to each other and experienced violent tides induced by mutual gravity. As further evidence, the face-on spiral galaxy on the right, also known as NGC 3808A, exhibits many young blue star clusters produced in a burst of star formation. The twisted edge-on spiral on the left (NGC 3808B) seems to be wrapped in the material bridging the galaxies and surrounded by a curious polar ring. Together, the system is known as Arp 87 and morphologically classified, technically, aspeculiar. While such interactions are drawn out over billions of years, repeated close passages should ultimately result in the death of one galaxy in the sense that only one galaxy will eventually result. Although this scenario does look peculiar, galactic mergers are thought to be common, with Arp 87 representing a stage in this inevitable process. The Arp 87 pair are about 300 million light-years distant toward the constellation Leo. The prominent edge-on spiral galaxy at the far left appears to be a more distant background galaxy and not involved in the on-going merger.


Rumors of a Dark Universe 
Image Credit: High-Z Supernova Search Team, HST, NASA
Explanation: Twenty-one years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant -- dark energy -- was directly implied by new distant supernova observations. Suggestions of a cosmological constant were not new -- they have existed since the advent of modern relativistic cosmology. Such claims were not usually popular with astronomers, though, because dark energy was so unlike known universe components, because dark energy's abundance appeared limited by other observations, and because less-strange cosmologies without a significant amount of dark energy had previously done well in explaining the data. What was exceptional here was the seemingly direct and reliable method of the observations and the good reputations of the scientists conducting the investigations. Over the two decades, independent teams of astronomers have continued to accumulate data that appears to confirm the existence of dark energy and the unsettling result of a presently accelerating universe. In 2011, the team leaders were awarded the Nobel Prize in Physics for their work. The featured picture of a supernova that occurred in 1994 on the outskirts of a spiral galaxy was taken by one of these collaborations.

Astronomy News:

[This looks like a variant on the Solar Gravity Lens concept Aerospace is involved with – but a bit closer to home.  Atmospheric refraction around earth it seems would be less uniform than gravitational bending around a star.]

A proposed space telescope would use Earth’s atmosphere as a lens

 https://www.sciencenews.org/article/proposed-space-telescope-would-use-earth-atmosphere-lens

The ‘terrascope’ would use a detector in space to collect refracted light



BIG SHOT  The bending of starlight caused by Earth’s atmosphere could be used to create a giant telescope, one scientist suggests, by placing a detector out in space (illustrated).
JAMES TUTTLE KEANE
By Emily Conover
AUGUST 9, 2019 AT 11:55 AM

Telescopes keep getting bigger — and more expensive. But what if there were a better way?
One astronomer has suggested a possible work-around: Turn the entire Earth into a telescope lens by using the planet’s atmosphere to bend and focus light.

When light from stars hits Earth’s atmosphere, the light bends, or refracts. That bending concentrates the rays, focusing them in a region of space on the opposite side of the planet. Put a spacecraft in the right spot — say, orbiting 1.5 million kilometers from Earth — and it could catch the focused rays, says David Kipping of Columbia University (SN: 10/14/17, p. 22). Instruments aboard the craft might be able to collect more light from dim objects than is possible by current telescopes on Earth. That means the terrascope, as Kipping calls his design, could potentially make ultrasensitive measurements, for example, revealing new features of exoplanets, such as mountain ranges or clouds, he says.

Kipping has outlined the idea in a study accepted in Publications of the Astronomical Society of the Pacific. But some scientists are questioning its merits. Astrophysicist Slava Turyshev of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., suggests that the concept is infeasible for a variety of reasons, from the difficulty of blocking out unwanted light from Earth to the possible blurring of images caused by light entering the atmosphere at different heights.

Others are a bit more optimistic. “There’s clearly a lot of work to do before we’ll know if it will work,” says Martin Elvis of the Harvard-Smithsonian Center for Astrophysics. “Even if this neat idea doesn’t pan out, this is the kind of creative thinking that will get astronomy out of the linear thinking trap of wanting a bigger version of what we already have.”

A version of this article appears in the September 14, 2019 issue of Science News.

CITATIONS

2019.           Kipping. The ‘terrascope’: On the possibility of using the Earth as an atmospheric lens. Publications of the Astronomical Society of the Pacific, in press, 2019.


A 3-D map of sta
rs reveals the Milky Way’s warped shape

Scientists used thousands of stars called Cepheids to trace the galaxy’s structure



BENT OUT OF SHAPE  A new map of the Milky Way made with Cepheid stars reveals the warped shape of the galaxy. In this image, those stars (green) are overlaid on top of an image of another warped galaxy, NGC 4565. The star icon indicates the sun.
J. SKOWRON/OGLE/ASTRONOMICAL OBSERVATORY/UNIV. OF WARSAW
By Emily Conover
AUGUST 1, 2019 AT 2:00 PM

Like a misshapen potato chip, our home galaxy is warped. A new 3-D map brings the contorted structure of the Milky Way’s disk into better view, thanks to measurements of special stars called Cepheids, scientists report in the Aug. 2 Science.

Making 3-D measurements of the galaxy requires estimating how far away stars are from Earth, typically a matter of guesswork. But unlike other stars, Cepheids vary in brightness over time in a particular way that can be used to determine a precise distance to each star.

Although the Milky Way’s disk is usually depicted as flat, previous observations had revealed that the galaxy is curved at its edges. The new study shows that that the Milky Way is even more warped than scientists had thought, says astronomer Dorota Skowron of the Astronomical Observatory of the University of Warsaw. If you took a spaceship into deep space and looked back at our galaxy, says Skowron, “you could see by eye” that it’s misshapen.

Skowron and colleagues made new observations of Cepheids as part of the Optical Gravitational Lensing Experiment, or OGLE. Combining those measurements with previously studied Cepheids resulted in 2,431 stars charted in the map.

The team also used the Cepheids’ regular brightness variations to estimate the stars’ ages. Younger Cepheids aligned with the Milky Way’s four main spiral arms, while the older stars were more scattered, a result of their dispersal over time as the galaxy rotates, a computer simulation suggests. The scientists were able to roughly reproduce the stars’ actual distributions by simulating stars forming in the galaxy’s arms and spreading out over time, helping scientists understand how the galaxy came to have its current structure.

VIDEO:  https://youtu.be/7ZWGX7HFf7g  The Milky Way’s Cepheid stars are plotted in three dimensions, revealing the galaxy’s warped shape. Unlike other stars, Cepheids vary in brightness in a particular way that helps scientists make more precise estimates of their distances from Earth. Brighter colors represent Cepheids closer to the warped plane of the galaxy, indicated by the grid. The star icon indicates the sun.

Questions or comments on this article? E-mail us at feedback@sciencenews.org

CITATIONS

D.M. Skowron et al. A three-dimensional map of the Milky Way using classical Cepheid variable stars. Science. Vol 365, August 2, 2019, p. 479. doi: 10.1126/science.aau3181.



 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 2019 Astronomy Lecture Series

Each year the Observatories organizes a series of public lectures on current astronomical topics.  These lectures are given by astronomers from the Carnegie Observatories as well as other research institutions.  The lectures are geared to the general public and are free.
– only 4 per year in the Spring www.obs.carnegiescience.edu.  For more information about the Carnegie Observatories or this lecture series, please contact Reed Haynie.  . Click here for more information.


6 Sept

Friday Night 7:30PM SBAS  Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw Bl. In Torrance)
Topic: “The Antikythera Mechanism” Ken Munson

6 September Friday, 8 PM CalTech Astro: Stargazing and Lecture Series “Observing Black Holes” a lecture by Marianne Heida. For directions, weather updates, and more information, please visit: http://outreach.astro.caltech.edu

9 Sept. 
LAAS General Mtg. 7:30pm Griffith Observatory (private)


12 Sept.
AEA Astronomy Club Meeting
Demo of Meade GoTo Scope & Another Lecture from “The Remarkable Science of Ancient Astronomy,” Prof. Bradley Schaefer?
(A1/1735)

Sept. 19 & 20 The von Kármán Lecture Series: 2019


It Broke! A Story of How we Fixed It


A story of how we repaired and saved a spacecraft that was millions of miles away.
Host:
Brian White
Speaker(s):
Dr. Marc Rayman,
Mission Director/Chief Engineer/Project Manager for Deep Space 1

Location:
Thursday, Sept. 19, 2019, 7pm
The von Kármán Auditorium at JPL
4800 Oak Grove Drive
Pasadena, CA
› Directions

Friday, Sept. 20, 2019, 7pm
Caltech’s Ramo Auditorium
1200 E California Blvd.
Pasadena, CA
› Directions

› Click here to watch the event live on Ustream
* Only the Thursday lectures are streamed live.
* Only the Thursday lectures are streamed live.




Sept 29, 2019

UCLA Meteorite Gallery Events

PROF. ED YOUNG

POLLUTED WHITE DWARFS

Location: Geology Building - Slichter Room 3656
Time: 2:30PM
When a star the size of the Sun has burned all its H and He, it starts to cool by radiation. It eventually becomes very dense; white dwarfs typically contain the mass of the Sun in an Earth-size star. The gravitational field is so strong that elements other than H and He settle out of the atmosphere on a short time scale (months to 106 years). Thus it was a surprise when detailed surveys showed 25% of white dwarfs to be polluted with asteroidal or cometary debris. Recent studies of WD atmospheres thus allow comparison of these pollutants with the smaller materials orbiting our Sun.

3 Oct.
AEA Astronomy Club Meeting
Pizza Party & ?
(A1/1735)

Observing:

The following data are from the 2019 Observer’s Handbook, and Sky & Telescope’s 2019 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 September:

   

Moon: Sept 5 1st quarter, Sept 13 Full, Sept 21 last quarter, Sept 28 new            
Planets: Venus visible at dusk after the 18th.  Mars hidden in Sun’s glow all month.  Mercury hidden in the Sun’s glow all month.  Saturn visible at dusk, sets after midnight. Jupiter visible at dusk, sets mid-evening.
Other Events:

6 Sept Jupiter 2 deg S. of Moon

4,11,18,25 Sept.
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


7 Sept.
LAAS Public  Star Party: Griffith Observatory Grounds 2-10pm See http://www.griffithobservatory.org/programs/publictelescopes.html#starparties  for more information.

10 September Neptune at Opposition

21 Sept.
SBAS In-town observing session – contact Greg Benecke to coordinate a location. http://www.sbastro.net/.  

23 Sept. Equinox

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

28 Sept.
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, Walt Sturrock, VP, Kelly Gov club Secretary (& librarian), or Alan Olson, Resource Committee Chairman (over equipment, and club Treasurer).

Mark Clayson,
AEA Astronomy Club President



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