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, August 5, 2018

2018 August


AEA Astronomy Club Newsletter August 2018

Contents

AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 1
Astronomy News p. 5
General Calendar p. 9
    Colloquia, lectures, mtgs. p. 9
    Observing p. 12
Useful Links p. 13
About the Club p. 14

Club News & Calendar.

Club Calendar

Club Meeting Schedule:

2 August
AEA Astronomy Club Meeting
Online or DVD Astronomy short lecture
(A1/1735)
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:  

The club’s FY19 AEA budget request has been submitted, including software for our new laptop (Starry Night Pro Plus 7 & Maxim DL Pro Suite), a new portable GoTo MCT (Meade ETX-90), an Android tablet & Sky Safari 5 Pro app, SkyFi III wireless scope controller, another Mt. Wilson night, quarterly pizza parties, Astronomical League group membership & Observer’s Handbook.

The Hubble Optics 16-inch ultralight/portable Dobsonian has been ordered, and should be here by early November (long production & shipping lead time from China).  Along with a large array of accessories, including digital setting circle.  We’ve also got a new 15-inch laptop for the club, and will begin loading it up with software (Starry Night, software with our various scopes and cameras, etc.). 

In September we will schedule a club tour of the Webb Telescope at NGC – sometime in the Fall.  Stay tuned.

We need volunteers to help with: 

·         Manning our Sept. 18 & 20 club table in A3 cafeteria from 11am to 1pm (AEA clubs showcase)
·         Populating our club Sharepoint site with material & links to the club’s Aerowiki & Aerolink materials
·         Arranging future club programs
·         Managing club equipment

Astronomy Video(s) & Picture(s) of the Month
(from Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html
An episode of George Takei Presents: “It's a big, big galaxy out there.”  https://www.messenger.com/t/ezesmith




Layers of the South Pole of Mars 
Image Credit & License: ESA/DLR/FU Berlin; Bill Dunford
Explanation: What lies beneath the layered south pole of Mars? A recent measurement with ground-penetrating radar from ESA's Mars Express satellite has detected a bright reflection layer consistent with an underground lake of salty water. The reflection comes from about 1.5-km down but covers an area 200-km across. Liquid water evaporates quickly from the surface of Mars, but a briny confined lake, such as implied by the radar reflection, could last much longer and be a candidate to host life such as microbes. Pictured, aninfrared, green, and blue image of the south pole of Mars taken by Mars Express in 2012 shows a complex mixture of layers of dirt, frozen carbon dioxide, and frozen water.
Cerealia Facula 
Image Credit: NASA, JPL-Caltech, UCLA, MPS/DLR/IDA
Explanation: Cerealia Facula, also known as the brightest spot on Ceres, is shown in this stunning mosaic close-up view. The high-resolution image data was recorded by the Dawn spacecraft, in a looping orbit, from altitudes as low as 34 kilometers (21 miles) above thedwarf planet's surface. Cerealia Facula is about 15 kilometers wide, found in the center of 90 kilometer diameter Occator crater. Like the other bright spots (faculae) scattered around Ceres, Cerealia Facula is not ice, but an exposed salty residue with a reflectivity like dirty snow. The residue is thought to be mostly sodium carbonate and ammonium chloride from a slushy brine within or below the dwarf planet's crust. Driven by advanced ion propulsion on an 11-year mission, Dawn explored main-belt asteriod Vesta before traveling on to Ceres. But sometime between this August and October, the interplanetary spacecraft is expected to finally run out of fuel for its hydrazine thrusters. The subsequent loss of control of its orientation will result in the loss of power and the ability to communicate with Earth. Meanwhile Dawn will continue to explore Ceres in unprecedented detail, and ultimately retire in its orbit around the small world.
A Northern Summer's Night 
Image Credit & License: Ruslan Merzlyakov (RMS Photography)
Explanation: Near a summer's midnight a mist haunts the river bank in this dreamlike skyscape taken on July 3rd from northern Denmark. Reddened light from the Sun a little below the horizon gives an eerie tint to low hanging clouds. Formed near the edge of space, the silvery apparitions above them are noctilucent or night shining clouds. The icy condensations on meteoric dust or volcanic ash are still in full sunlight at the extreme altitudes of the mesophere. Usually seen at high latitudes in summer months, wide spread displays of the noctilucent clouds are now being reported.

Astronomy News:
(from https://www.sciencedaily.com )

Thin gap on stellar family portrait

Date: July 26, 2018
Source: Georgia State University
Summary:
A thin gap has been discovered on the Hertzsprung-Russell Diagram (HRD), the most fundamental of all maps in stellar astronomy, a finding that provides new information about the interior structures of low mass stars in the Milky Way Galaxy, according to a new study.
Share:

The European Space Agency's Gaia mission has produced the richest star map of our galaxy to date.
Credit: Satellite: Gaia Copyright ESA/Ga
ia/DPAC
A thin gap has been discovered on the Hertzsprung-Russell Diagram (HRD), the most fundamental of all maps in stellar astronomy, a finding that provides new information about the interior structures of low mass stars in the Milky Way Galaxy, according to a study led by astronomers at Georgia State University.
Just as a graph can be made of people with different heights and weights, astronomers compare stars using their luminosities and temperatures. The HRD is a "family portrait" of the stars in the Galaxy, where stars such as the Sun, Altair, Alpha Centauri, Betelgeuse, the north star Polaris and Sirius can be compared. The newly discovered gap cuts diagonally across the HRD and indicates where a crucial internal change occurs in the structures of stars. The gap outlines where stars transition from being larger and mostly convective with a thin radiative layer to being smaller and fully convective.
Radiation and convection are two ways to transfer energy from inside a star to its surface. Radiation transfers energy through space, and convection is the transfer of energy from one place to another by the movement of fluid.
The researchers estimate that stars above the gap contain more than about one-third the mass of the Sun, and those below have less mass. Because different types of stars have different masses, this feature reveals where different types of interior structures are on the HRD. The gap occurs in the middle of the region of "red dwarf" stars, which are much smaller and cooler than the Sun, but compose three of every four stars in the solar neighborhood. The findings are published in the journal The Astrophysical Journal Letters.
"We were pretty excited to see this result, and it provides us new insights to the structures and evolution of stars," said Dr. Wei-Chun Jao, first author of the study and a staff astronomer in the Department of Physics and Astronomy at Georgia State.
In 2013, the European Space Agency (ESA) launched the Gaia spacecraft to make a census of the stars in the Milky Way Galaxy and to create a three-dimensional map. In April 2018, the ESA released results of this mission, revealing an unprecedented map of more than one billion stars in the Galaxy, a 10,000-fold increase in the number of stars with accurate distances. The research team led by Georgia State plotted nearly 250,000 of the closest stars in the Gaia data on the HRD to reveal the gap. Georgia State's researchers have studied the distances to nearby stars for years, which enabled them to interpret the results and notice this thin gap.
The team is now working to pinpoint why the gap is present. Using results from a theoretical computer model that simulates the activity inside the stars, it appears the gap is caused by a slight shrinking in size if a star is convective all the way through.

Story Source:
Materials provided by Georgia State University. Note: Content may be edited for style and length.

Journal Reference:
1.       Wei-Chun Jao, Todd J. Henry, Douglas R. Gies, Nigel C. Hambly. A Gap in the Lower Main Sequence Revealed by Gaia Data Release 2. The Astrophysical Journal, 2018; 861 (1): L11 DOI: 10.3847/2041-8213/aacdf6

Mars Express detects liquid water hidden under planet’s south pole

Date:  July 26, 2018
Source: European Space Agency
Summary:
Radar data collected by ESA's Mars Express point to a pond of liquid water buried under layers of ice and dust in the south polar region of Mars.

ESA’s Mars Express has used radar signals bounced through underground layers of ice to find evidence of a pond of water buried below the south polar cap.
Credit: Context map: NASA/Viking; THEMIS background: NASA/JPL-Caltech/Arizona State University; MARSIS data: ESA/NASA/JPL/ASI/Univ. Rome; R. Orosei et al 2018
Radar data collected by ESA's Mars Express point to a pond of liquid water buried under layers of ice and dust in the south polar region of Mars.
Evidence for the Red Planet's watery past is prevalent across its surface in the form of vast dried-out river valley networks and gigantic outflow channels clearly imaged by orbiting spacecraft. Orbiters, together with landers and rovers exploring the martian surface, also discovered minerals that can only form in the presence of liquid water.
But the climate has changed significantly over the course of the planet's 4.6 billion year history and liquid water cannot exist on the surface today, so scientists are looking underground. Early results from the 15-year old Mars Express spacecraft already found that water-ice exists at the planet's poles and is also buried in layers interspersed with dust.
The presence of liquid water at the base of the polar ice caps has long been suspected; after all, from studies on Earth, it is well known that the melting point of water decreases under the pressure of an overlying glacier. Moreover, the presence of salts on Mars could further reduce the melting point of water and keep the water liquid even at below-freezing temperatures.
But until now evidence from the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument, MARSIS, the first radar sounder ever to orbit another planet, remained inconclusive.
It has taken the persistence of scientists working with this subsurface-probing instrument to develop new techniques in order to collect as much high-resolution data as possible to confirm their exciting conclusion.
Ground-penetrating radar uses the method of sending radar pulses towards the surface and timing how long it takes for them to be reflected back to the spacecraft, and with what strength. The properties of the material that lies between influences the returned signal, which can be used to map the subsurface topography.
The radar investigation shows that south polar region of Mars is made of many layers of ice and dust down to a depth of about 1.5 km in the 200 km-wide area analysed in this study. A particularly bright radar reflection underneath the layered deposits is identified within a 20 km-wide zone.
Analysing the properties of the reflected radar signals and considering the composition of the layered deposits and expected temperature profile below the surface, the scientists interpret the bright feature as an interface between the ice and a stable body of liquid water, which could be laden with salty, saturated sediments. For MARSIS to be able to detect such a patch of water, it would need to be at least several tens of centimetres thick.
"This subsurface anomaly on Mars has radar properties matching water or water-rich sediments," says Roberto Orosei, principal investigator of the MARSIS experiment and lead author of the paper published in the journal Science today.
"This is just one small study area; it is an exciting prospect to think there could be more of these underground pockets of water elsewhere, yet to be discovered."
"We'd seen hints of interesting subsurface features for years but we couldn't reproduce the result from orbit to orbit, because the sampling rates and resolution of our data was previously too low," adds Andrea Cicchetti, MARSIS operations manager and a co-author on the new paper.
"We had to come up with a new operating mode to bypass some onboard processing and trigger a higher sampling rate and thus improve the resolution of the footprint of our dataset: now we see things that simply were not possible before."
The finding is somewhat reminiscent of Lake Vostok, discovered some 4 km below the ice in Antarctica on Earth. Some forms of microbial life are known to thrive in Earth's subglacial environments, but could underground pockets of salty, sediment-rich liquid water on Mars also provide a suitable habitat, either now or in the past? Whether life has ever existed on Mars remains an open question, and is one that Mars missions, including the current European-Russian ExoMars orbiter and future rover, will continue to explore.
"The long duration of Mars Express, and the exhausting effort made by the radar team to overcome many analytical challenges, enabled this much-awaited result, demonstrating that the mission and its payload still have a great science potential," says Dmitri Titov, ESA's Mars Express project scientist.
"This thrilling discovery is a highlight for planetary science and will contribute to our understanding of the evolution of Mars, the history of water on our neighbour planet and its habitability."
Mars Express launched 2 June 2003 and celebrates 15 years in orbit on 25 December this year.
The MARSIS instrument was funded by the Italian Space Agency (ASI) and NASA and developed by the University of Rome, Italy, in partnership with NASA's Jet Propulsion Laboratory.

Story Source:
Materials provided by European Space Agency. Note: Content may be edited for style and length.

Journal Reference:
1.       R. Orosei, S. E. Lauro, E. Pettinelli, A. Cicchetti, M. Coradini, B. Cosciotti, F. Di Paolo, E. Flamini, E. Mattei, M. Pajola, F. Soldovieri, M. Cartacci, F. Cassenti, A. Frigeri, S. Giuppi, R. Martufi, A. Masdea, G. Mitri, C. Nenna, R. Noschese, M. Restano, R. Seu. Radar evidence of subglacial liquid water on Mars. Science, 2018; eaar7268 DOI: 10.1126/science.aar7268


 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.
2 August
AEA Astronomy Club Meeting
Online or DVD Astronomy short lecture
(A1/1735)






10 Aug
Friday Night 7:30PM SBAS  Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw Bl. In Torrance)
Topic: “TBA” Ken LeGore, Skywatcher USA







Aug 26




UCLA Meteorite Gallery --
Location: UCLA Campus

DR. CANDACE KOHL

COLLECTION OF METEORITES FROM ANTARCTIC ICE FIELDS

Location: Geology 3656
Time: 2:30PM
Many very important meteorites have been collected from the “cold storage” of the Antarctic ice sheet. This continent-wide glacier is gradually moving towards the ocean; in some areas erosion by winds exposes meteorites on the surface. Candace will tell us about her experiences as a member of a collection team in Antarctica and also about participation on a team that collected a long core of Greenland ice to analyze for variations in cosmic-ray produced isotopes.

13 Aug
LAAS General Mtg. 7:30pm Griffith Observatory

 

The von Kármán Lecture Series: 2018

 

Spitzer Beyond: The incredible continuing adventures of the Spitzer Space Telescope

Aug. 9 &10
The Spitzer Space Telescope is one of NASA’s Great Observatories, designed to observe the universe in infrared light. It was launched in 2003 with an expected lifetime of 5 years. Spitzer has succeeded beyond our wildest expectations, now routinely observing transiting exoplanets and other interesting astronomical phenomena in its 15th year of operations. I will discuss some of the novel engineering feats that have made the extended operation of Spitzer possible as well as some of the technical challenges that we are now facing. I will also present some recent science highlights including science that Spitzer was not designed to do such as the discovery and characterization of seven rocky, potentially habitable planets in the nearby TRAPPIST-1 system.
Speaker:
Dr. Sean Carey, Manager of the Spitzer Science Center, Caltech/IPAC
Sean received his PhD in astronomy from Rensselaer Polytechnic Institute in 1995. Prior to arriving at Caltech in 2002, he worked at Boston College and the Air Force Research Laboratory helping to produce an infrared survey of the Galactic plane with the MSX satellite. At Caltech, he has worked at IPAC in various roles at the Spitzer Science Center including leading the instrument support team for the Infrared Array Camera (IRAC) on Spitzer before becoming the manager of the Spitzer Science Center in 2016. Sean has diverse research interests from exoplanets to massive star formation to near-Earth asteroids. He enjoys the challenges of calibrating infrared instruments and likes to give data away to the community in the form of large surveys of the plane of our Galaxy.
Location:
Thursday, August 9, 2018, 7pm
The von Kármán Auditorium at JPL
4800 Oak Grove Drive
Pasadena, CA
› Directions

Friday, August 10, 2018, 7pm
Caltech’s Ramo Auditorium
1200 E California Blvd.
Pasadena, CA
› Directions


6 Sept
AEA Astronomy Club Meeting
TBA
(A1/1735)

Observing:

The following data are from the 2018 Observer’s Handbook, and Sky & Telescope’s 2018 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 August:

 


Moon: Aug 4 last quarter, Aug 11 new, Aug 18 1st quarter, Aug 26 Full,               
Planets: Venus visible at dusk.  Mars visible at dusk, highest near midnight.  Mercury visible at dawn after the 20th.  Saturn visible at dusk, sets after midnight. Jupiter visible at dusk, sets late evening.
Other Events:

1 August Alpha Capricornids Meteor Shower Peak This shower has infrequent but relatively bright meteors, with some fireballs. Zenith-Hourly Rates is usually 2-5/hour.

 
4 Aug
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 August Southern Iota Aquarids Meteor Shower Peak The Aquarid Meteor Shower consists of two diffuse branches. The Southern branch peaks on 6 August and has a ZHr of 7-8.

10 August New Moon

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


1,8,15,22,29 Aug
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 Aug
LAAS Private dark sky  Star Party

12 August Perseids Meteor Shower Peak Typical one of the best observed meteor showers, the Perseids usually have a ZHr of 50-80 at the peak of the shower.

17 August Venus at Greatest Eastern Elongation

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

25 August Northern Aquarids Meteor Shower Peak The second branch of the Aquarids Meteor shower, this one has a typical ZHr of 5-10 meteors per hour.

26 August Full Moon

26 August Mercury at Greatest Western Elongation

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, 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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