AEA Astronomy Club
Newsletter
June 2022
Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 2
Astronomy News p. 10
General Calendar p. 13
Colloquia, lectures, mtgs. p. 13
Observing p. 14
Useful
Links p. 16
About the Club p.
17
Club News &
Calendar.
Club Calendar
Club Meeting Schedule:
--
2 June AEA Astronomy Club Meeting TBD – Great Courses video Teams
7 July AEA Astronomy Club Meeting TBD – Great Courses video Teams
AEA
Astronomy Club meetings are now on 1st Thursdays at 11:30 am. Virtual meetings on Teams until further
notice. When live meetings resume, our
preferred room has been A1/1735, when we can reserve it.
Club
News:
Mt.
Wilson – Tentative reservation requests have been made for the 60-inch
Oct. 21 (Friday), and 100-inch Oct. 22 (Sat.).
This year would normally be our every-other-year for the 60-inch, but we
put in the 100-inch request as backup in case we don’t get the 60-inch.
2024
Eclipse -- An update from the
2024 solar eclipse committee (Mark Clayson, Mai Lee, Melissa Jolliff, Nahum
Melamed, Judy Kerner, Marilee Wheaton):
We continue to try to nail down a hotel, but it may be
a while (several months?) as most are not yet taking reservations or
negotiating contracts. We’ll continue to
keep you informed. But typical group
contracts allow individual group members to make their individual reservations
and deposits directly with the hotel.
And deposits may not be required until month(s) before the stay.
Contact Jason Fields if interested in joining him for an observing
night with his 20” Dobs.
We need volunteers to help with:
·
Serving
as club Astronomical League representative
·
Installing
our new software on our tablet & laptop
·
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, Sam has a fair chunk of the equipment)
Astronomy Video(s)
& Picture(s) of the Month
(generally from
Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html)
VIDEO: Simulation TNG50: A Galaxy Cluster Forms https://apod.nasa.gov/apod/ap220529.html
Video Credit: IllustrisTNG
Project; Visualization: Dylan Nelson (Max Planck Institute for Astrophysics)
et al.
Music: Symphony No. 5 (Ludwig van Beethoven),
via YouTube Audio Library
Explanation: How do clusters of galaxies form? Since our universe moves
too slowly to watch, faster-moving computer simulations are created to help
find out. A recent effort is TNG50 from IllustrisTNG, an upgrade of the
famous Illustris Simulation.
The first part of the featured
video tracks cosmic gas (mostly hydrogen) as it evolves into galaxies and galaxy clusters from
the early universe to today, with brighter colors marking faster moving gas. As
the universe matures, gas falls into gravitational wells,
galaxies forms, galaxies spin, galaxies collide and merge, all while black holes form in galaxy
centers and expel surrounding gas at high speeds. The second half
of the video switches
to tracking stars, showing a galaxy cluster coming together complete with tidal tails and stellar streams. The
outflow from black holes in TNG50 is surprisingly complex
and details are being compared with our real universe. Studying
how gas coalesced in the early universe helps
humanity better understand how our Earth, Sun,
and Solar
System originally formed.
VIDEO: A
Martian Eclipse: Phobos Crosses the Sun https://apod.nasa.gov/apod/ap220509.html
Video Credit: NASA, JPL-Caltech, ASU MSSS, SSI
Explanation: What's that passing in front of the Sun? It looks like a
moon, but it can't be Earth's Moon,
because it isn't round. It's the Martian moon Phobos.
The featured
video was taken from the surface of Mars a
month ago by the Perseverance rover. Phobos, at 11.5
kilometers across, is 150 times smaller than Luna (our moon) in
diameter, but also 50 times closer to its parent planet. In
fact, Phobos is so close to Mars that it is expected to
break up and crash into Mars within
the next 50 million years. In the near term, the low orbit of Phobos results in more
rapid solar eclipses than seen from Earth.
The featured
video is shown in real time -- the transit really
took about 40 seconds,as shown. The videographer -- the robotic rover Perseverance (Percy)
-- continues to explore Jezero
Crater on Mars,
searching not only for clues to the watery history of the now dry world, but evidence
of ancient
microbial life.
Rocket Transits Rippling Sun
Image Credit & Copyright: Michael Cain
Explanation: The launch of a rocket at sunrise can result in unusual but
intriguing images that feature both the rocket and the Sun. Such was the case
last month when a SpaceX Falcon 9 rocket blasted off from
NASA's Kennedy
Space Center carrying 53 more Starlink satellites into low
Earth orbit. In the featured
launch picture, the rocket's exhaust plume glows
beyond its projection onto the distant Sun, the rocket itself
appears oddly
jagged, and the Sun's lower edge shows peculiar drip-like ripples.
The physical
cause of all of these effects is pockets of relatively hot or rarefied
air deflecting
sunlight less strongly than pockets relatively cool or compressed
air: refraction. Unaware of the
Earthly show, active sunspot region 3014 --
on the upper left -- slowly crosses the Sun.
The Milky Way's Black Hole
Image Credit: X-ray - NASA/CXC/SAO,
IR - NASA/HST/STScI; Inset: Radio
- Event Horizon Telescope Collaboration
Explanation: There's
a black hole at the center of the Milky Way. Stars are observed to orbit a
very massive and compact
object there known as Sgr A* (say "sadge-ay-star").
But this just released radio image (inset) from planet Earth's Event
Horizon Telescope is the first direct evidence of the Milky Way's
central black hole. As predicted by Einstein's Theory of General Relativity,
the four million solar mass black hole's strong gravity is bending light and
creating a shadow-like dark central region surrounded by a bright ring-like
structure. Supporting observations made by space-based telescopes and
ground-based observatories provide a wider view of the galactic center's
dynamic environment and an important context for the Event Horizon Telescope's
black hole image. The
main panel image shows the X-ray data from Chandra and infrared data
from Hubble. While the main panel is about 7 light-years across, the Event
Horizon Telescope inset image itself spans a mere 10 light-minutes at
the center of our galaxy, some 27,000
light-years away.
The Lively Center of the Lagoon Nebula
Image Credit: NASA, ESA, Hubble; Processing
& Copyright: Mehmet
Hakan Özsaraç
Explanation: The center of the Lagoon Nebula is a whirlwind of spectacular star formation. Visible near the image center, at least two long funnel-shaped clouds, each roughly half a light-year long, have been formed by extreme stellar winds and intense energetic starlight. A tremendously bright nearby star, Herschel 36, lights the area. Vast walls of dust hide and redden other hot young stars. As energy from these stars pours into the cool dust and gas, large temperature differences in adjoining regions can be created generating shearing winds which may cause the funnels. This picture, spanning about 10 light years, combines images taken in six colors by the orbiting Hubble Space Telescope. The Lagoon Nebula, also known as M8, lies about 5000 light years distant toward the constellation of the Archer (Sagittarius).
NGC 1316: After Galaxies Collide
Image Credit & Copyright: Capture: Greg Turgeon; Processing: Kiko Fairbairn
Explanation: Astronomers turn detectives when trying to figure out the
cause of startling sights like NGC
1316. Investigations indicate that NGC 1316 is an
enormous elliptical
galaxy that started, about 100 million years ago, to devour a
smaller spiral
galaxy neighbor, NGC
1317, just on the upper right. Supporting evidence includes the dark dust lanes characteristic
of a spiral galaxy,
and faint swirls and shells of stars and gas visible in this wide and deep
image. One thing that >remains
unexplained is the unusually small globular star clusters,
seen as faint dots on the image. Most elliptical galaxies have more and
brighter globular clusters than NGC 1316.
Yet the observed globulars are
too old to have been created by the recent spiral collision. One
hypothesis is that these globulars survive
from an even earlier galaxy that
was subsumed into NGC
1316. Another surprising attribute of NGC 1316, also known as
Fornax A, is its giant
lobes of gas that glow brightly in radio waves.
Ice Halos by Moonlight
Image Credit & Copyright: Alan Dyer, Amazingsky.com, TWAN
Explanation: An almost full moon on April 15 brought these luminous
apparitions to a northern spring night over Alberta Canada. On that night,
bright moonlight refracted and reflected by hexagonal ice crystals in high
clouds created a complex of halos and
arcs more commonly seen
by sunlight in daytime skies. While the colors of the arcs and
moondogs or paraselenae were just visible to the unaided eye, a blend of
exposures ranging from 30 seconds to 1/20 second was used to render this
moonlit wide-angle skyscape. The Big Dipper at the top of the frame sits just
above a smiling and
rainbow-hued circumzenithal arc. With Arcturus left and Regulus toward
the right the Moon is centered in its often spotted 22 degree halo. May 15 will
also see the bright light of a Full Moon shining in Earth's night skies.
Tomorrow's Full Moon will be dimmed for a while though, as it slides through
Earth's shadow in a total lunar
eclipse.
Spiral Galaxy NGC 1512: The Inner Rings
Image Credit: NASA, ESA, Hubble Space
Telescope
Explanation: Most galaxies don't have any rings -- why does this galaxy
have two? To begin, the bright band near NGC 1512's center is a nuclear ring, a ring that
surrounds the galaxy center and glows brightly with recently formed stars. Most
stars and accompanying gas and dust, however, orbit the
galactic center in a ring much further out -- here seen near the image edge.
This ring is called, counter-intuitively,
the inner ring. If you look closely, you will see this the inner
ring connects ends of a diffuse central bar that runs
horizontally across the galaxy. These ring structures are thought to be caused
by NGC 1512's own
asymmetries in a drawn-out process called secular
evolution. The gravity of
these galaxy asymmetries, including the bar of stars, cause gas and dust to
fall from the inner ring to the nuclear ring, enhancing this ring's rate
of star formation. Some spiral galaxies also
have a third ring -- an outer ring that circles the
galaxy even further out.
Mercury's Sodium Tail
Image Credit & Copyright: Sebastian Voltmer
Explanation: That's no comet. Below the Pleiades star cluster is
actually a planet: Mercury. Long exposures of our Solar System's
innermost planet may reveal something unexpected: a tail. Mercury's thin atmosphere contains
small amounts of sodium that
glow when excited by light from the Sun. Sunlight also liberates these atoms
from Mercury's surface and
pushes them away. The yellow glow from sodium, in particular, is
relatively bright. Pictured, Mercury and its sodium
tail are visible in a deep image taken last week from La Palma, Spain through a filter that
primarily transmits yellow
light emitted by sodium. First predicted in
the 1980s, Mercury's tail was first discovered in
2001. Many tail details were revealed in multiple
observations by NASA's
robotic MESSENGER
spacecraft that orbited Mercury between 2011 and 2015. Tails,
of course, are usually associated with comets.
Astronomy
News:
From
ScienceNews.org
The sun’s
searing radiation led to the shuffling of the solar system’s planets
Sunlight
evaporating gas jumbled the giant planets’ orbits, simulations suggest
Sunlight heating and evaporating the disk of gas and dust around a
young star (as seen in this illustration) may have triggered a shift in the
orbits of the still-forming giant planets in the solar system’s early history.
JPL-CALTECH/NASA
By Liz
Kruesi
MAY 10, 2022 AT
7:00 AM
In the solar system’s early years, the still-forming giant
planets sidestepped, did a do-si-do and then swung one of their partners away
from the sun’s gravitational grasp. Things settled, and our planetary system
was in its final configuration.
What triggered that planetary shuffle has been unknown. Now,
computer simulations suggest that the hot radiation of the young sun evaporating its planet-forming disk of gas and dust led
to the scrambling of the giant planets’ orbits, researchers report in the April
28 Nature.
As a result, the four largest planets may have been in their
final configuration within 10 million years of the solar system’s birth about
4.6 billion years ago. That’s much quicker than the 500 million years that
previous work had suggested.
The planetary-shuffling mechanism that the team uncovered in the
computer simulations is very innovative, says Nelson Ndugu, an astrophysicist
who studies forming planetary systems at North-West University in
Potchefstroom, South Africa, and Muni University in Arua, Uganda. “It has huge
potential.”
Heaps of evidence, including observations of extrasolar planetary systems
forming (SN:
7/2/18),
had already indicated that something in our solar system’s early history
jumbled the giant planets’ orbits, which scientists call the giant-planet instability (SN: 5/25/05).
“The evidence for the giant-planet instability is really
robust,” says Seth Jacobson, a planetary scientist at Michigan State University
in East Lansing. “It explains many features of the outer solar system,” he
says, like the large number of rocky
objects beyond Neptune that make up the Kuiper Belt (SN: 12/31/09).
To figure out what triggered that instability, Jacobson and
colleagues ran computer simulations of the thousands of ways that the early
solar system could have developed. All started with a young star and a
planet-forming disk of gas and dust surrounding the star. The team then altered
the disk parameters, such as its mass, density and how fast it evolved.
The simulations also included the still-forming giant planets —
five of them, in fact. Astronomers think a third ice giant, in addition to Uranus and
Neptune, was originally a solar system member (SN: 4/20/12). Jupiter and Saturn
round out the final tally of these massive planets.
When the sun officially became a star, that is, the moment it
began burning hydrogen at its core — roughly 4.6 billion years ago — its
ultraviolet emission would have hit the disk’s gas, ionizing it and heating it
to tens of thousands of degrees. “This is a very well-documented process,”
Jacobson says. As the gas heats, it expands and flows away from the star,
beginning with the inner portion of the disk.
“The disk disperses its gas from inside out,” says Beibei Liu,
an astrophysicist at Zhejiang University in Hangzhou, China. He and Jacobson
collaborated with astronomer Sean Raymond of Laboratoire d’Astrophysique de
Bordeaux in France in the new research.
In the team’s simulations, as the inner part of the disk
dissolves, that area loses mass, so the embedded, still-forming planets feel
less gravity from that region, Jacobson says. But the planets still feel the
same amount of pull from the disk’s outer region. This gravitational torquing,
as the team calls it, can trigger a rebound effect: “Originally, the planets
migrate in, and they reach the [inner] edge of this disk, and they reverse
their migration,” Liu says.
Because of Jupiter’s large mass, it’s mostly unaffected. Saturn,
though, moves outward and into the region, which, in the simulations, holds the
three ice giant planets. That area becomes crowded, Liu says, and close
planetary interactions follow. One ice giant gets kicked out of the solar
system entirely, Uranus and Neptune shift a bit farther from the sun, and “they
gradually form the orbits close to our solar system’s configuration,” Liu says.
In their computer simulations, the researchers found that as the
sun’s radiation evaporates the disk, a planetary reshuffle nearly always
ensues. “We can’t avoid this instability,” Jacobson says.
Now that the researchers have an idea of what may have caused
this solar system shuffle, the next step is to simulate how the evaporation of
the disk could affect other objects.
“We’ve focused really
heavily on the giant planets, because their orbits were the original
motivation,” Jacobson says. “But now, we have to do the follow-up work to show
how this trigger mechanism relates to the small bodies.”
Questions or comments on this article? E-mail us at feedback@sciencenews.org
CITATIONS
B. Liu, S.N. Raymond and S.A.
Jacobson. Early solar system instability triggered by dispersal of the
gaseous disk. Nature. Vol. 604,
April 28, 2022, p. 643. doi: 10.1038/s41586-022-04535-1.
About Liz
Kruesi
·
E-mail
Liz Kruesi is the temporary
astronomy news writer for Science News. She
has written about astronomy and space since 2005, and received the AAS
High-Energy Astrophysics Division science journalism award in 2013. She holds a
bachelor’s degree in physics from Lawrence University in Appleton, Wisc.
General Calendar:
Colloquia,
Lectures, Seminars, Meetings, Open Houses & Tours:
Colloquia: Carnegie (Tues.
11am), UCLA, Caltech (Wed. 4pm), IPAC (Wed. 12:15pm) & other Pasadena
(daily
12-4pm): http://obs.carnegiescience.edu/seminars/
https://carnegiescience.edu/events/carnegie-digital-series
Carnegie Zoom Digital Series
Zoom Webinar Platform
January Night Sky
Network Clubs & Events https://nightsky.jpl.nasa.gov/clubs-and-events.cfm
2 June AEA Astronomy Club Meeting TBD – Great Courses video Teams
June
3 will be the 1st since COVID
Friday Night 7:30PM SBAS Monthly General Meeting
in the Planetarium at El Camino College (16007 Crenshaw Bl. In Torrance)
June
23 The von Kármán Lecture Series: 2022
Spacecraft Assembly, Test, and Launch Operations (ATLO)
In
this image, taken on June 13, 2019, engineers at JPL install the starboard legs
and wheels on NASA's Mars 2020 rover.
Credit: NASA/JPL-Caltech
Spacecraft Assembly, Test, and Launch Operations (ATLO)
June 23
Time: 7 p.m. PDT (10 p.m. EDT; 0300 UTC)
What does it take to
build a spacecraft? It’s up to the Spacecraft Assembly, Test, and Launch
Operations (ATLO) team to assemble it, bake it, shake it, get it to the pad and
launch it.
Speaker(s):
Michelle Tomey Colizzi, Mechanical Engineer, NASA/JPL
Luis A Dominguez, ATLO Electrical & Dep. Systems Lead, NASA/JPL
Host:
Nikki Wyrick, Public Services Office, NASA/JPL
Co-Host:
Brian White, Public Services Office, NASA/JPL
Webcast:
Click here
to watch the event live on YouTube
7 July AEA Astronomy Club Meeting TBD – Great Courses video Teams
Observing:
The
following data are from the 2022 Observer’s Handbook, and Sky & Telescope’s
2022 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 June:
Moon June 7 1st quarter, June 14
Full, June 21 last quarter, June 29 new
Planets:
Venus
is visible in the east at dawn all month. Mars
visible at dawn all month. Jupiter
visible at dawn low all month. Saturn rises around midnight and is
visible until dawn. Mercury
is visible at dawn beginning on the 16th.
Other
Events:
LAAS Event Calendar (incl.
various other virtual events):
https://www.laas.org/laas-bulletin/#calendar
|
June 1, 8, 15, 22, 29 |
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. Time: 7:30
PM - 10:00 PM Location: Garvey
Ranch Obs. , 781 Orange Ave., Monterey Park, CA 91755 |
16 June Mercury
greatest elongation W (23deg)
21 June Solstice
22 June Mars 0.9deg N
of Moon
24 June Uranus
0.05deg N of Moon
|
25 June? |
SBAS In-town
observing session – In Town Dark Sky Observing Session at
Ridgecrest Middle School– 28915 NortbBay Rd. RPV, Weather Permitting: Please
contact Ken Munson to confirm that the gate will be opened. http://www.sbastro.net/. Only if we get
permission to use the school grounds again and CDC guidelines are reduced |
|
25 June |
LAAS Private dark
sky Star Party |
26 June Venus 3deg S of Moon
Cancelled LAAS Public Star Party: Griffith Observatory Grounds 2-10pm See http://www.griffithobservatory.org/programs/publictelescopes.html#starparties for more information.
|
28 June |
SBAS
out-of-town Dark Sky observing – contact Ken Munson to coordinate a location.
http://www.sbastro.net/. |
Internet
Links:
Telescope, Binocular & Accessory Buying
Guides
Sky & Telescope Magazine -- Choosing Your Equipment
Orion Telescopes & Binoculars -- Buying
Guides
Telescopes.com -- Telescopes 101
General
Getting Started in Astronomy & Observing
e! Science News Astronomy & Space
Astronomical Society of the Pacific (educational, amateur &
professional)
Amateur Online Tools, Journals, Vendors, Societies, Databases
The Astronomy White Pages (U.S. & International
Amateur Clubs & Societies)
American Astronomical Society
(professional)
Regional
(Southern California, Washington, D.C. & Colorado)
Southern California & Beyond
Amateur Astronomy Organizations, Observatories & Planetaria
Mt. Wilson Observatory description, history, visiting
Los Angeles Astronomical Society (LAAS)
South Bay Astronomical Society
(SBAS)
The Local Group Astronomy Club
(Santa Clarita)
Ventura County Astronomical
Society
The
Astronomical Society of Greenbelt
Northern
Virginia Astronomy Club
Colorado
Springs Astronomical Society
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 Kaly Rengarajan, 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: Jason Fields, President & Program Committee Chairman, Sam
Andrews, VP, Kelly Gov club Secretary (& librarian), or Kaly Rangarajan,
(Treasurer).
Mark Clayson,
AEA Astronomy Club Newsletter Editor
