AEA
Astronomy Club Newsletter April
2021
Contents
AEA Astronomy Club News & Calendar p.1
Video(s) & Picture(s) of the Month p. 2
Astronomy News p. 10
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:
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AEA Astronomy Club Meeting |
TBD -- Great Courses video |
Teams |
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AEA Astronomy Club Meeting |
TBD -- Great Courses video |
Teams |
AEA
Astronomy Club meetings are now on 1st Thursdays at 11:30 am. For 2020:
Jan. & Feb. in A1/1735, March 5 in A1/2906 and for the rest of 2020 (April
to Dec.) virtual meetings on Teams.
Club
News:
After too many years, and just in time for Mark Clayson’s
retirement, we had an election. And with
the exception of Kelly Gov, a clean slate of officers. Jason Fields has long been affiliated with
the club, given presentations on astrophotography, hosted star parties, and is
a sensor system specialist, etc. And
helped assemble and collimate our 16-inch Meade Dobs. Sam Andrews is new to Aerospace, but has a
degree in astronomy, and works under Jason in her day job. Kaly Rangarajan has also long been involved
with the club, and lately has helped with the club website migration to
Sharepoint.
Election results:
President – Jason Fields
Vice President – Sam Andrews
Secretary – Kelly Gov
Treasurer – Kaly Rangarajan
We should also note that Arthur Martirosyan has
volunteered, and Jason has appointed him, to be our equipment manager – a
much-needed position.
We need volunteers to help with:
·
Assembling
our new 16-inch Hubble Optics Dobs
·
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)
Astronomy Video(s)
& Picture(s) of the Month
(generally from
Astronomy Picture of the Day, APOD: http://apod.nasa.gov/apod/archivepix.html)
VIDEO:
Meteor Fireballs in Light and Sound https://apod.nasa.gov/apod/ap210315.html
Image Credit & Copyright: Thomas Ashcraft (Radio Fireball Observatory)
Explanation: Yes, but have you ever heard a meteor?
Usually, meteors are too
far away to make any audible sound. However, a meteor will
briefly create an ionization
trail that can reflect a distant radio signal. If the geometry is
right, you may momentarily
hear -- through your radio -- a distant radio station even over static.
In the featured video,
the sounds of distant radio transmitters were caught reflecting from large
meteor trails by a sensitive radio receiver -- at the same time the bright streaks were
captured by an all-sky
video camera. In the video, the bright paths taken by
four fireballs
across the sky near Lamy, New Mexico, USA,
are shown first. Next, after each static frame, a real-time video captures
each meteor streaking across
the sky, now paired with the sound recorded from its radio reflection.
Projecting a meteor trail down to the Earth may
lead to finding its impact
site (if any), while projecting its trail
back into the sky may lead to identifying its parent comet or asteroid.
M87's Central Black Hole in Polarized Light
Image Credit: Event
Horizon Telescope Collaboration; Text: Jayanne English (U. Manitoba)
Explanation: To play on Carl
Sagan’s famous
words "If you wish to make black hole jets, you must first
create magnetic fields." The featured
image represents the detected intrinsic
spin direction (polarization)
of radio
waves. The polarizationi is
produced by the powerful magnetic
field surrounding the supermassive black hole at the center
of elliptical
galaxy M87.
The radio waves were detected by the Event Horizon Telescope (EHT),
which combines data from radio telescopes distributed
worldwide. The polarization
structure, mapped using computer generated flow
lines, is overlaid on EHT’s
famous black hole image, first published in 2019. The full 3-D
magnetic field is complex.
Preliminary analyses
indicate that parts of the field circle around the black hole
along with the accreting
matter, as expected. However, another
component seemingly veers vertically away from the black hole.
This component could explain
how matter resists falling in and is instead launched
into M87’s
jet.
Pillars of the Eagle Nebula in Infrared
Image Credit: NASA, ESA, Hubble, HLA; Processing: Luis Romero
Explanation: Newborn stars are forming in the Eagle Nebula.
Gravitationally contracting in pillars of dense gas
and dust, the intense radiation of these newly-formed bright stars is causing
surrounding material to boil away. This image, taken with
the Hubble Space
Telescope in near infrared light, allows
the viewer to see
through much of the thick dust that makes the
pillars opaque in
visible light. The giant structures are light years in
length and dubbed informally the Pillars of Creation.
Associated with the open
star cluster M16,
the Eagle Nebula lies about 6,500 light years away.
The Eagle Nebula is
an easy target for small telescopes in a nebula-rich part of the sky toward
the split constellation Serpens Cauda (the tail
of the snake).
Red Sprite Lightning over the Andes
Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas Observatory, TWAN)
Explanation: What are those red filaments in the sky? They are a rarely seen form of lightning confirmed only about 30 years ago: red sprites. Recent research has shown that following a powerful positive cloud-to-ground lightning strike, red sprites may start as 100-meter balls of ionized air that shoot down from about 80-km high at 10 percent the speed of light. They are quickly followed by a group of upward streaking ionized balls. The featured image was taken earlier this year from Las Campanas observatory in Chile over the Andes Mountains in Argentina. Red sprites take only a fraction of a second to occur and are best seen when powerful thunderstorms are visible from the side.
AUDIO: SuperCam
Target on Ma'az https://apod.nasa.gov/apod/ap210313.html
Image Credit: NASA/JPL-Caltech/LANL/CNES/CNRS
Explanation: What's the sound of one
laser zapping? There's no need to consult a Zen master to find out,
just listen to the first acoustic
recording of laser shots on Mars. On Perseverance mission sol 12 (March 2)
the SuperCam instrument atop the rover's mast zapped a rock dubbed Ma'az 30
times from a range of about 3.1 meters. Its
microphone recorded the soft staccato popping sounds of the rapid
series of SuperCam laser zaps. Shockwaves created in the thin martian
atmosphere as bits of rock are vaporized by the laser shots make the popping
sounds, sounds that offer clues to the physical structure of the target. This SuperCam
close-up of the Ma'az target region is 6 centimeters (2.3 inches)
across. Ma'az means Mars in the
Navajo language.
Perseverance Takes a Spin
Image Credit: NASA, JPL-Caltech, Mars 2020
Explanation: After arriving at Jezero Crater on Mars, Perseverance
went for a spin on March 4. This
sharp image from the car-sized rover's Navcam shows
tracks left by its six wheels in
the martian soil. In preparation for operations on the surface of the Red
Planet, its first drive lasted about 33 minutes. On a short and successful test
drive Perseverance
moved forward 4 meters, made a 150 degree turn in place, backed up for
2.5 meters, and now occupies a different parking
space at its newly christened Octavia
E. Butler Landing location. Though the total travel distance of the
rover's first outing was about 6.5 meters (21 feet), regular commutes of 200
meters or more can be expected in the
future.
Perseverance 360: Unusual Rocks and the Search for Life on Mars https://apod.nasa.gov/apod/ap210309.html
Image Credit: NASA, JPL-Caltech, ASU, MSSS
Explanation: Is that a fossil?
Looking through recent images of
Mars taken by the new Perseverance
rover may seem a bit like treasure hunting, with the possibility of
fame coming to the first person to correctly identify a petrified bone,
a rock imprinted by an ancient
plant, or any clear indication that life once existed on Mars.
Unfortunately, even though it is possible that something as spectacular as a
skeleton could be identified, most exobiologists think
it much more likely that biochemical
remnants of ancient single-celled microbes could
be found with Perseverance's chemical
analyzers. A key
reason is that multicellular
organisms may take a greater amount of oxygen to
evolve than has ever
been present on Mars. That said, nobody's
sure, so please feel free to digitally magnify any Perseverance image that
interests you -- including the featured
360-degree zoomable image of the rocks and ridges surrounding
Perseverance's landing location in Jezero Crater. And
even though NASA-affiliated
scientists are themselves studying Perseverance's images, if you see
anything really
unusual, please post it to popular
social media. If your sighting turns out to be particularly
intriguing, scientifically, it is likely that NASA will hear about it.
The Pelican Nebula in Red and Blue
Image Credit & Copyright: M.
Petrasko, M. Evenden, U.
Mishra (Insight
Obs.)
Explanation: The Pelican Nebula is changing. The entire nebula,
officially designated IC 5070, is divided from the larger North America Nebula by
a molecular cloud filled
with dark dust.
The Pelican,
however, is particularly interesting because it is an unusually active mix
of star formation and
evolving gas clouds. The featured
picture was processed to bring out two main colors, red and blue, with
the red dominated by light emitted by interstellar hydrogen. Ultraviolet light emitted
by young energetic stars is slowly transforming cold gas in the nebula to hot
gas, with the advancing
boundary between the two, known as an ionization front, visible
in bright red across the image center. Particularly dense tentacles of
cold gas remain. Millions of years from now this nebula might no longer be
known as the Pelican,
as the balance
and placement of stars and gas will surely leave something that appears
completely different.
The Surface of Venus from Venera 14
Image Credit: Soviet
Planetary Exploration Program, Venera
14;
Processing & Copyright: Donald Mitchell &
Michael Carroll (used with permission)
Explanation: If you could stand on Venus --
what would you see? Pictured is the view from Venera 14, a robotic Soviet lander which
parachuted and air-braked
down through the thick Venusian atmosphere in March of 1982. The desolate
landscape it saw included flat rocks, vast empty terrain, and a featureless sky
above Phoebe
Regio near Venus'
equator. On the lower left is the spacecraft's penetrometer used
to make scientific measurements, while the light piece on the right is part of
an ejected lens-cap. Enduring temperatures near
450 degrees Celsius and pressures 75
times that on Earth, the hardened Venera
spacecraft lasted only about an hour. Although data from Venera 14 was
beamed across the inner Solar
System almost 40 years ago, digital processing and merging
of Venera's
unusual images continues even today. Recent analyses of infrared measurements taken
by ESA's
orbiting Venus
Express spacecraft indicate that active volcanoes may currently
exist on Venus.
Astronomy
News:
New study sows doubt about the composition of 70 percent of our
universe
Date:
March 31,
2021
Source:
University
of Copenhagen - Faculty of Science
Summary:
Researchers the world over have long believed
that 70 percent of the universe is composed of dark energy, a substance that
makes it possible for the universe to expand at an ever-increasing rate. But in
a new study, researchers tested a model which suggests that the universe's
expansion is due to a dark substance with a kind of magnetic force.
FULL STORY
Until
now, researchers have believed that dark energy accounted for nearly 70 percent
of the ever-accelerating, expanding universe.
For many
years, this mechanism has been associated with the so-called cosmological
constant, developed by Einstein in 1917, that refers to an unknown repellent
cosmic power.
But because
the cosmological constant -- known as dark energy -- cannot be measured
directly, numerous researchers, including Einstein, have doubted its existence
-- without being able to suggest a viable alternative.
Until now. In a new study by researchers at the University of
Copenhagen, a model was tested that replaces dark energy with a dark matter in
the form of magnetic forces.
"If
what we discovered is accurate, it would upend our belief that what we thought
made up 70 percent of the universe does not actually exist. We have removed
dark energy from the equation and added in a few more properties for dark
matter. This appears to have the same effect upon the universe's expansion as
dark energy," explains Steen Harle Hansen, an associate professor at the
Niels Bohr Institute's DARK Cosmology Centre.
The
universe expands no differently without dark energy
The usual
understanding of how the universe's energy is distributed is that it consists
of five percent normal matter, 25 percent dark matter and 70 percent dark
energy.
In the UCPH
researchers' new model, the 25 percent share of dark matter is accorded special
qualities that make the 70 percent of dark energy redundant.
"We
don't know much about dark matter other than that it is a heavy and slow
particle. But then we wondered -- what if dark matter had some quality that was
analogous to magnetism in it? We know that as normal particles move around,
they create magnetism. And, magnets attract or repel other magnets -- so what
if that's what's going on in the universe? That this constant expansion of dark
matter is occurring thanks to some sort of magnetic force?" asks Steen
Hansen.
Computer
model tests dark matter with a type of magnetic energy
Hansen's question served as the foundation for the new computer
model, where researchers included everything that they know about the universe
-- including gravity, the speed of the universe's expansion and X, the unknown
force that expands the universe.
"We
developed a model that worked from the assumption that dark matter particles
have a type of magnetic force and investigated what effect this force would have
on the universe. It turns out that it would have exactly the same effect on the
speed of the university's expansion as we know from dark energy," explains
Steen Hansen.
However,
there remains much about this mechanism that has yet to be understood by the
researchers.
And it all
needs to be checked in better models that take more factors into consideration.
As Hansen puts it:
"Honestly, our discovery may just be a coincidence. But if it isn't, it is truly incredible. It would change our understanding of the universe's composition and why it is expanding. As far as our current knowledge, our ideas about dark matter with a type of magnetic force and the idea about dark energy are equally wild. Only more detailed observations will determine which of these models is the more realistic. So, it will be incredibly exciting to retest our result.
Story
Source:
Materials provided by University of
Copenhagen - Faculty of Science. Note:
Content may be edited for style and length.
Journal
Reference:
1. Loeve, Karoline; Nielsen, Kristine Simone; Hansen, Steen H. Consistency analysis of a Dark Matter velocity dependent force as an alternative to the Cosmological Constant. Submitted to arXiv, 2021 [abstract]
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/
March Night Sky Network
Clubs & Events
https://nightsky.jpl.nasa.gov/clubs-and-events.cfm
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AEA Astronomy Club Meeting |
TBD -- Great Courses video |
Teams |
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Cancelled
for now |
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Friday Night 7:30PM SBAS Monthly General Meeting in the Planetarium at El Camino College (16007 Crenshaw
Bl. In Torrance) |
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April
15 The von Kármán Lecture Series: 2020
ence on Ice:
What Ice Says About Past, Present, and Future ClimateApr. 15
Time: 7 p.m.
PDT (10 p.m. EDT; 0200 UTC)
Celebrate Earth Day with us as we explore the world’s ice and what it can tell
us about our climate. We’ll talk with scientist Alex Gardner about our
cryosphere and how it affects our future.
Host:
Nikki Wyrick, Public Services Office, NASA/JPL
Co-Host:
Jocelyn Argueta, Public Outreach Specialist, NASA/JPL
Speaker(s):
Alex Gardner, Glacier Scientist, NASA/JPL
Webcast:
YouTube link coming soon
Click here to watch the
event live on Ustream
Past shows
are archived on YouTube.
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12 April |
LAAS General Mtg. 7:30pm Griffith Observatory
(private) |
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TBD |
UCLA METEORITE SCIENTISTS
No events scheduled currently. |
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6 May |
AEA Astronomy Club Meeting |
TBD -- Great Courses video |
(Teams) |
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Observing:
The
following data are from the 2021 Observer’s Handbook, and Sky & Telescope’s
2021 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 April:
Moon: April 4 last quarter,
April 12 new, April 20 1st quarter, April 27 Full
Planets:
Venus
emerges at dusk after the 18th. Mars
is visible at dusk and sets after midnight. Jupiter and Saturn are
visible at dawn and rise less than 4 hours before the Sun mid-month, Mercury
is visible at dusk after the 25th.
Other
Events:
|
Cancelled |
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 |
|
? |
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 |
|
10 April |
LAAS Private dark
sky Star Party |
|
? |
SBAS
out-of-town Dark Sky observing – contact Ken Munson to coordinate a location.
http://www.sbastro.net/. |
April 17 Mars 0.1deg N of Moon, occultation
April 22 Lyrids Meteors
|
Cancelled |
LAAS Public
Star Party: Griffith Observatory Grounds 2-10pm See http://www.griffithobservatory.org/programs/publictelescopes.html#starparties for more information. |
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
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