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Journal of the Amateur Astronomers Association of New York
May 2015 Volume 64 Number 5; ISSN 0146-7662
Speeding Away: Seeing Supernovae in an Expanding Universe
By Amy Wagner
On Nov 11, 1572,
Tycho Brahe looked up
in the sky and saw a star
“new and never before
seen in the life or
memory of anyone.” Just
as Copernicus’s revolu-
tions of heavenly bodies
caused a revolution in
scientific thinking thirty
years before, Brahe’s new
stars created a new under-
standing of the cosmos.
On Apr 17, Robert Fisher
of the University of Mas-
sachusetts paid tribute to Brahe and his “nova stella” – a su-
pernova – for the AAA Lecture Series at the American Muse-
um of Natural History in his presentation, “Exploding Stars
and the Accelerating Cosmos.” Fisher’s enjoyable and in-
formative talk described these phenomena, which continue to
transform our knowledge of the universe centuries later.
What Brahe saw dispelled the still held ancient Aristo-
telean belief that nothing in the heavens ever changes. As it
turns out, Brahe’s “new star” was actually the death of an old
one. Today, we can still see the remnant of Tycho’s Superno-
va, thanks to imaging by the Chandra X-ray Observatory. But
SN1572 is more than just a curiosity from science history, it is
a special kind of supernova, a Type 1a, which has been used
to prove the existence of dark energy and that our universe is
expanding at an accelerated rate.
Supernovae come in two flavors. Some are thermonu-
clear explosions, while others are caused by the core-collapse
of massive stars. Type 1a supernovae are in the first group,
and the reason they are so special is that they always shine
with the same brightness. With these “standard candles,” we
can compare how bright they look (apparent brightness) with
how bright we know they are (intrinsic brightness) to figure
out how far away they are. “They are the best instruments we
have for measuring distance,” said Fisher. And, they are very
THIS MONTH: AAA Lecture May 1, Spring StarFest May 2, Astro Answers May 8, & Annual Meeting May 21
AAA LECTURE
Johns Hopkins Applied Physics Lab
Seen here before launch in 2004, NASA’s MESSENGER ended its Mercury mission in April with an intentional impact on the planet. Among its discoveries since arriving in 2011, the probe found over 100 billion tons of water ice and organics.
Rockland Rocks Astronomy with NAIC and NEAF
By Stan Honda
Rockland County was the place to be for astronomy
in April. Some of the best astro-photographers in the world
converged on the Crowne Plaza Hotel in Suffern, NY on
April 16 & 17 for the 10th Annual Northeast Astro-Imaging
Conference (NEAIC), which was held in conjunction with the
Northeast Astronomy Forum (NEAF) at Rockland Communi-
ty College on April 18 & 19. Both events were hosted by the
Rockland Astronomy Club.
This year, about 170 participants heard speakers from a
variety of disciplines present at NEAIC, which is one of the
three largest imaging conferences in the world. The other
two are the Advanced Imaging Conference, coming up in San
Jose, CA in October, and the Central European Deep Sky
Imaging Conference (CEDIC), which was held in Linz, Aus-
tria this March. NEAIC Chairman Bob Moore tries to offer a
diversity of topics for the presentations: “People are interest-
ed in details of processing images, in science, such as pro-am
collaborations, supernova counts, in planetary and solar im-
aging and how to capture these elusive objects. Past at-
tendees have done some of the top images in the world.”
Planetary imager Christopher Go from the Philippines
gave a talk at NEAIC and even conducted a workshop/
Stan Honda
The Northeast Astronomy Forum (NEAF) was held at Rockland Commu-nity College from April 18-19.
NASA/CXC/Rutgers/J.Warren & J.Hughes et al
A Chandra X-ray image of the rem-nant of SN 1572, known as “Tycho’s Supernova,” a Type 1a supernovae.
(NAIC and NEAF (cont’d on Page 8) AAA Lecture (cont’d on Page 7)
ASTRO EVENTS
2
May’s Evening Planets: Mars is visible until about 8
PM in Taurus the Bull. Venus can be found in Gemini the
Twins until 11 PM. Bright Jupiter will be in Cancer the Crab
until 2 AM, setting earlier every morning until midnight by
the end of the month. Find Saturn between Scorpius the
Scorpion and Libra the Scales at 9 PM, and then earlier every
evening; it will be up all night. Mercury is in Taurus the Bull
during the first half of May for about two hours after sunset.
May’s Evening Stars: Spot Spica in Virgo the Virgin,
Arcturus in Boötes the Herdsman, Vega in Lyra the Harp,
and Castor and Pollux in Gemini the Twins. Also find the
stars of constellations Cassiopeia, Cepheus, Draco, Virgo,
Hercules, Ophiuchus, Leo, Cancer, Corona Borealis, and the
two Dippers during the month.
May’s Morning Planets: Saturn is up between Scorpi-
us the Scorpion and Libra the Scales until sunrise. Neptune
will be in Aquarius the Water Bearer as of 4 AM, rising earli-
er every morning by 2 AM at the end of May. Uranus rises in
Pisces the Fish about an hour after Neptune. Dwarf planet
Pluto will be in Sagittarius the Archer by 1 AM, rising earlier
every night through the month
May’s Morning Stars: Saturn is up between Scorpius
the Scorpion and Libra the Scales until sunrise. Neptune will
be in Aquarius the Water Bearer as of 4 AM, rising earlier
every morning by 2 AM at the end of May. Uranus rises in
Pisces the Fish about an hour after Neptune. Dwarf planet
Pluto will be in Sagittarius the Archer by 1 AM, rising earlier
every night through the month
May 3 Full Moon at 11:40 PM
May 6 Eta Aquarid meteor shower peaks (dawn)
May 11 Last Quarter Moon at 6:35 PM
May 14 Moon at perigee (227,435 mi from Earth)
May 18 New Moon at 12:15 AM
May 19 Mercury 6° north of the Moon (morning)
May 22 Saturn at opposition, magnitude 0.0
(brightest in 2015)
May 24 Jupiter 5° north of the Moon (morning)
May 25 First Quarter Moon at 1:15 PM
May 26 Moon at apogee (251,185 mi from Earth)
Times given in EDT.
WHAT’S UP IN THE SKY
May 2015
May’s Eta Aquarids Meteor Shower
The Eta Aquarid meteor shower peaks this month, and the
best viewing opportunity will be in the early morning hours
of May 6, from around 2:00 AM until dawn. Its shooting
stars will be more frequent at peak, but many can still be seen
in the few days before and after.
What causes the Eta Aquarids?
Meteor showers are created when the Earth passes through
the trail of a comet. Comet Halley is responsible for the Eta
Aquarids display. As debris from the comet enters Earth’s
atmosphere at high speed, the meteors burn up, creating a
spectacle of shooting stars.
Halley orbits the sun every 76 years and it will be back
in 2061. The Earth passes through Halley's orbit in October
too creating the Orionid meteor shower.
What is a Radiant?
In a meteor shower,
the shooting stars
appear to strike
everywhere in the
sky, but their paths
trace back to one
region in the sky.
The spot where
they originate is
called the radiant.
The meteors travel in parallel paths. Just as train tracks meet
at a vanishing point on the horizon, shooting stars appear to
radiate from a single point, due to perspective.
Meteor showers are named for the constellation that coin-
cides with their radiant. Hence, Eta Aquarids originate from
the star Eta in the constellation Aquarius .
Who can see the Eta Aquarids?
This meteor shower favors the skies of the southern hemi-
sphere. Those who live further south will see more meteors.
The southern hemisphere has the chance to see over 20 mete-
ors per hour at peak under dark skies. However, a waning
gibbous Moon on May 6 will reduce the visibility of many
shooting stars. The southern U.S., most of Europe, and Cen-
tral Asia will see about 10 per hour; the northern U.S., Cana-
da, North Europe, and North Asia will see about 5 per hour.
How can I view the meteor shower?
Looking east to southeast, the meteors will seem to originate
from the Y-shaped Water Jar in the constellation Aquarius.
Find a dark spot, far away as possible from light pollution,
and hope for clear skies. There is no need for any equipment
to view the meteor shower, and you don’t need to know the
constellations. Just look up, and enjoy!
Follow veteran sky watcher Tony Faddoul each month, as he points our minds and our scopes toward the night sky.
AAA Observers’ Guide
By Tony Faddoul
May “Skylights”
3
May 2015
Minding Mercury Check out that Bling!
A new study suggests that Mercury, which is consid-
erably less reflective than the Moon, is darker because it
has been battered by dust from comets containing car-
bon. Other air less bodies, like the Moon, are dark from
dust and solar wind that coat the surface in iron nanoparti-
cles. However, spectroscopy from NASA’s MESSENGER
spacecraft, which ended its mission in April, shows that Mer-
cury’s surface contains very little iron. "It's long been hy-
pothesized that there's a mystery darkening agent that's con-
tributing to Mercury's low reflectance," said Megan Bruck
Syal, an author on the study. "One thing that hadn't been
considered was that Mercury gets dumped on by a lot of ma-
terial derived from comets." As comets approach the Sun,
they start to break apart, and nearby Mercury is right in the
path of their dust. Comet dust can be composed of up to
25% carbon. It is estimated that 50 times as many of these
carbon-rich micrometeorites hit Mercury per unit surface
area than hit the Moon. Experiments show that the velocity
of comet dust impacts would not only embed carbon and
darken the planet’s surface, but also produce graphite and
even nanodiamonds. Mercury is a dark place, but it still
sparkles. AMW
Sources: nature.com; sciencedaily.com.
NASA/Ames/Brown University
Carbon in comet dust bombarding Mercury may be the reason why its surface is so dark. A study shows impact material is significantly darker in the presence of carbon and complex organics (right) than without (left).
Mad for Mars A Martian Marathon
In March,
NASA’s Mars Explo-
ration Rover Oppor-
tunity finished a mar-
athon in record time:
11 years and two
months. The long-
distance champion of
off-Earth vehicles ar-
rived on the Red Planet
in 2004 for a three-
month mission and
found evidence that
liquid water once flowed there. Exceeding expectations, its
mission was extended and the rover was sent on a drive to
Endeavor crater. There, it has learned that wet conditions on
ancient Mars were less acidic and more favorable for microbi-
al life than previously thought. "This mission isn't about set-
ting distance records, of course; it's about making scientific
discoveries on Mars and inspiring future explorers to achieve
even more," said principal investigator Steve Squyres. "Still,
running a marathon on Mars feels pretty cool."
Meanwhile, NASA’s Curiosity rover has detected life
essential nitrogen on the surface of Mars. Nitrogen star ts
as N2 gas in the atmosphere, and the tightly bound atoms must
be separated, or “fixed,” for use in chemical reactions, like
building DNA, RNA, and proteins. While heating Martian
sediments, Curiosity saw nitric oxide (NO) released by the
breakdown of nitrate (NO3), a source of fixed nitrogen. On
Earth, most nitrogen is fixed by microorganisms; however,
the Mars nitrates were not fixed biologically on the inhospita-
ble planet. They likely came from energy released during
meteorite impacts and lightning in Mars’ past, yet "finding a
biochemically accessible form of nitrogen is more support for
the ancient Martian environment at Gale Crater being habita-
ble," said Jennifer Stern of NASA. AMW Source: nasa.gov.
NASA/JPL-Caltech
Not one to bask in its glory, NASA's Mars Exploration Rover Opportunity was back to work analyzing Martian rocks after completing a marathon in March.
Out of This World A Year in Space and the Twins Study
On March 27, American Astronaut Scott Kelly and Russian Cosmo-
naut Mikhail Kornienko launched to the International Space Station to
begin the historic One-Year Mission in space, an international par tnership
between the two countries. They will be on the ISS for twice as long as typical
missions last. Four Russian cosmonauts have previously spent a consecutive
year or more in space; now Kelly will be the first American to join the club.
Scientists hope to understand more about the psychological and biomedical
challenges of long duration spaceflight and to learn how to reduce the human
risks in space exploration. In conjunction with the mission, a separate set of
investigations called the Twins Study will be conducted on Scott Kelly at
the ISS and on his astronaut twin brother, Mark, here on Earth. Scientists
hope to gain broader insight into changes that may occur in the physiology,
behavior, microbiome, and molecular activity for these genetically identical
humans living in two very different environments. This month, Time Maga-
zine will air the first episode of its documentary series, A Year in Space, which will follow the Kelly brothers over the course of
the mission. Watch the trailer here - http://time.com/space-nasa-scott-kelly-mission/. AMW Source: nasa.gov.
Robert Markowitz
Astronauts Scott and Mark Kelly are the subjects of NASA’s Twins Study. Scott launched to the ISS in March for a one-year mission, during which the ef-fects of spaceflight on his body and behavior will be compared to Mark here on Earth.
4
A Polar Solar Eclipse
By Stan Honda
The light began to fade – faster, and then faster.
Through a solar filter I could make out a thin orange crescent.
Then a shout surged up from the crowd: “Filters off!” In the
minus 7 °F temperatures, I struggled with numb fingers to
remove the protective filters from the lenses of my two cam-
eras. I looked up and caught the last rays of sunlight. Then,
it seemed like someone had flipped the light switch. A black
Sun hovered over the horizon, circled by a glowing white
corona. And we stood in the shadow of the Moon.
A total solar eclipse is one of nature’s wonders. Wit-
nessing it very near the top of the world in sub-zero tempera-
tures adds another dimension to the experience. So that’s
why AAA members Tony Hoffman, Eileen Thornton Renda,
and I signed up for a Travel Quest tour to see the March 20
total solar eclipse in the northern polar region. Fellow AAA
member Michael Kentrianakis journeyed separately with sci-
entists from Williams College and the University of Hawaii.
The path of the eclipse’s totality arched across the north
Atlantic and Arctic Oceans, its shadow only touching land in
two places: the Faeroe Islands off the coast of Iceland and
the archipelago of Svalbard, an island group controlled by
Norway. The tour company offered trips to both locations,
but we chose Svalbard, because it had a slightly better weath-
er forecast. Renowned eclipse meteorologist Jay Anderson,
who has only been clouded out once, picked it too.
Our destination was the town of Longyearbyen on the
island of Spitsbergen, home to the northernmost settlement in
the world – a boast of its businesses, like the local sushi res-
taurant. About 2,300 people live there year-round, and we
were part of the 1,500 or so visitors expected for the eclipse.
At a latitude of 78 degrees north, Longyearbyen gives
the word “cold” new meaning. In the days leading up to the
eclipse, daytime highs reached 12 °F. On the morning of
March 20, the thermometer outside my hotel window read
minus 17 °C (1.4 °F) and rose to a balmy minus 16 °C (3 °F)
May 2015
at the start of the eclipse. One report claimed that the temper-
ature dropped to minus 22 °C (minus 7 °F) during totality.
One challenge in photographing the eclipse was finding
a location where the mountains surrounding Longyearbyen
would not obscure the Sun, which would be only 11 degrees
above the horizon at totality. Travel Quest found a beautiful
site with an unobstructed view of the eclipse to the south.
Standing with my New York colleagues and the friends
we had made on the tour, I set up two tripods and cameras: a
Nikon D800 with a 14-24mm wide-angle lens and a D810
with an 80-400mm telephoto zoom. I taped Thousand Oaks
Optical black polymer solar filter sheets to a custom-made
holder on the wide angle and to a lens hood on the telephoto.
I carried extra batteries for the cameras in a pocket near my
body to keep them warm. About 10 minutes before totality, I
put a new battery in each camera. A spare camera I wore
around my neck – a Sony a7S – was running low on power,
so I changed that battery as well.
The intervalometers for my two main cameras were set
to take a shot each minute – this way I could get a whole se-
ries of images from the start of the eclipse to the very end.
Later, I would assemble the shots in a time-lapse sequence on
my computer. The spot meter on the telephoto camera read
an exposure of 1/500 sec, f11 at ISO 400 through the solar
filter. This looked good on the camera screen, so I stuck with
those settings until the Sun became a thin crescent. Then, I
opened up one stop to 1/250 sec. Exposure for totality was
another matter altogether.
Most of the research I had done before the trip suggested
that the brightness of the corona is comparable to that of a full
Moon. I had on file a “Supermoon” photo that I shot at 1/500
sec, f10, ISO 800, so I kept those numbers in mind. I decided
to keep the ISO at 400 and change the shutter speed during
totality, which is not an easy task when you have only 2
minutes and 15 seconds or so to make the changes, bracket
the exposures (with gloves on), and try to actually watch the
eclipse with the naked eye.
After hearing the “Filters off!” cry, I shot multiple
frames and managed to capture with the telephoto the
eclipse’s second contact as a diamond ring formed around the
FOCUS ON THE UNIVERSE
Stan Honda
Second contact: The Diamond Ring. Nikon D810 camera, 80-400mm zoom lens at 400mm. Exposure: 1/250 sec., f11, ISO 400.
Polar Solar Eclipse (cont’d on page 9)
AAA’s Tony Hoffman, Eileen Thronton Renda, and Stan Honda in Longyearbyen on the Spitsbergen island in Svalbard, Norway just before the start of the total solar eclipse.
5
May 2015
Hubble Hubbub The 25th Anniversary of Hubble!
On April 24, NASA’s Hubble, the world’s first space
telescope, celebrated 25 years in orbit. Since its 1990
launch aboard the Space Shuttle Discovery, this remarkable
eye-in-the-sky has forever changed our understanding of the
universe and humanity’s place in it. The cultural impact of
Hubble has been profound, revealing to us what the cosmos
actually looks like – far from our tiny perch on Earth. Cir-
cling above us at 17,000 mph, Hubble has travelled over 3
billion miles to date, taking snapshots of the Solar System
and beyond. 340 miles high, it is free from interference by
the atmosphere. Its unprecedented images of breathtaking
galaxies, nebulae, and other celestial objects have become
iconic, showing us a universe full of wonders that we could
only have imagined before, one that defies imagination.
“Hubble has completely transformed our view of the uni-
verse, revealing the true beauty and richness of the cosmos”
said John Grunsfeld, astronaut and associate administrator of
NASA’s Science Mission Directorate. Meanwhile, Hubble’s
NASA
Hubble, the world’s first space telescope, has an unobstructed view of the universe from Earth orbit. Launched in 1990, it cir-cles above the distortion of Earth’s atmosphere and far above rain clouds and light pollution.
quarter-century of scientific contributions are impossible to
quantify. Its ability to peer back in time to capture light from
galaxies over 13 billion years ago has allowed scientists track
the development of our universe. By studying pulsing Cephe-
id variable stars, Hubble helped determine the precise age of
the universe. Looking at luminous quasars, it found there
were galaxies behind the glare and that those galaxies are
powered by giant black holes. Hubble also showed that nearly
all galaxies with bright, active centers have supermassive
black holes. And dark energy? Yeah, that was Hubble too.
Nobel Laureate Adam Reiss’s observations of Type 1a super-
novae made with Hubble were critical to the discovery in 1998
that our universe is expanding at an accelerated rate, changing
astrophysics forever. That finding helped make the case to
continue upgrades in the face of budget cuts. But when a 2004
service mission was cancelled in the wake of the Columbia
Space Shuttle disaster, outcries from scientists and an affec-
tionate public struggled to be heard. That mission finally re-
sumed in 2009, and Hubble received its last and most chal-
lenging repairs during a nail-biting rescue. Today, Hubble is
no longer alone in its quest. Other space observatories have
been launched, and the veteran telescope is there to support its
siblings, especially in the search for exoplanets. Exoplanets
have been discovered by the Kepler Space Telescope during
transit events, where an orbiting planet briefly dims its star’s
light. Hubble takes a closer look at those transits for clues
about the planets. It made the first measurements ever of ex-
trasolar planet compositions, seeing atmospheres and even
finding the first organic molecule on an exoplanet. Hubble
also took the first visible-light image of an exoplanet – For-
malhaut b. By studying the atmospheres of planets around
other stars, perhaps someday soon Hubble will spot one that is
just like Earth. I hope the inhabitants of that world are lucky
enough to have a Hubble too. AMW
Sources: hubblesite.org; nasa.gov.
NASA
Astronauts John M. Grunsfeld and Richard M. Linnehan shown replacing the Power Control Unit on the Hubble Space Tele-scope during a servicing mission in 2002.
NASA, ESA, Hubble Heritage Team, et al.
NASA celebrated the 25th Anniversary of the Hubble Space Telescope with the release of this glorious image of giant star cluster Westerlund 2 (center). Only 2 million years old, its 3,000 stars are some of the hottest, brightest, and most massive known. It resides in the Gum 29 nebula, 20,000 light-years away in the constellation Carina.
6
May 2015
enormously challenging to
keep the habitats they build
powered, and they will
need the help of any availa-
ble resource. Small depos-
its of methane or other car-
bon compounds will be
very welcome. But mining
these materials is not the
only issue.
Coal, oil, and methane
burn in power plants via
oxidation, and large con-
centrations of free floating
oxygen molecules don’t
exist on Mars as they do on
Earth. Its atmosphere is
nearly all carbon dioxide with a bit of nitrogen. Oxygen would
have to be extracted from the CO2 or from Mars’ plentiful po-
lar water ice. But, this demands a significant amount of ener-
gy. It could require more energy to mine the organics and pro-
duce oxygen than would be created. In that case, fossil fuels
would be too inefficient for a colony’s primary power.
But could they be viable as a secondary energy source for
Mars cars? Imagine an SUV designed with a storage tank for
portable oxygen to ignite gasoline. Such a vehicle could
transport equipment and personnel for miles, and colonists
could have some off-road fun traversing the Martian terrain.
Colonists on Mars will also have to manufacture any
goods or parts they need, as shipments from Earth are prohibi-
tively expensive. Methane can be used as a feedstock to make
polymer plastics for mining tools, medical supplies, spare
parts, and even whole vehicles. The first mass production fac-
tory on Mars will likely use plastics.
Methane would be beneficial to human survival on Mars,
but if it is not found in sufficient quantity, colonists could cre-
ate their own. Microbes could be housed on farms, thriving on
the CO2 in the Martian atmosphere to produce the needed natu-
ral gas. And, the organic waste of the colonists would become
a valuable food source to these methane-makers.
Of course, as humans venture to other worlds, they will
want to avoid making the same mistakes we’ve made on Earth.
While burning carbon compounds and releasing CO2 into
Mars’ atmosphere sounds like trouble, it may not be a bad idea
at all. The average temperature on Mars is well below freezing
– it never gets warmer than a mild spring day on Earth – so
Mars could use a little global warming. However, heating an
atmosphere adds energy to its weather systems, so Martian
colonists would be in for stronger winds and sandstorms –
making a tough environment even harder for exploration.
But, let’s keep this in perspective. An optimistic occupa-
tion of Mars over the next thousand years would mean a socie-
ty of only a few tens of thousands of people. Even if they left
bigger carbon footprints than today’s humans, it would mean
very little on a planetary scale. And, there is no indigenous
Martian life to protect. Greenpeace won’t need to set up a
chapter on Mars. So, let’s get to it. Drill, baby, drill!
Black Gold on the Red Planet
By Richard Brounstein
For better or worse, Earth is loaded with carbon-
based fossil fuels, a by-product of the abundant life and
planetary processes that have evolved over its 4.5 billion
years. More recently, humans harnessed coal, oil, and
natural gas for uses on which our entire modern existence
relies. Plastics, cosmetics, fabrics, lubricants, medicines,
cleaning supplies, and of course, fuel, all depend on these
decayed carbon compounds. While a concerted effort is be-
ing made to leverage more environmentally-friendly materi-
als, one cannot deny how readily useful fossil fuels are. What
if these resources were also on Mars? What could they mean
for a future Martian colony?
In December 2014, NASA’s Curiosity rover discovered
the organic chemical methane on Mars. Methane is a green-
house gas produced on Earth by microbes living in animals,
humans, landfills, hot springs, and marshlands. It is the main
component of natural gas, used to heat and cool our homes,
fuel some vehicles, and manufacture polymers for plastic
products. It is quickly becoming the transition fuel from oil
as cities move toward cleaner, sustainable energy sources.
Curiosity found that the Martian methane is fluctuating,
so it must have sources and sinks adding and removing the
organic today. But despite signs that Mars was a warmer,
wetter world millions of years ago, there is still no evidence
that microbes live there now or existed there ever. However,
there are non-biological ways to produce methane through an
interaction between water and abundant olivine rock. Still,
the absence of evidence is not the evidence of absence – there
may in fact be microbes on Mars currently making methane.
And though it may be unlikely that complex organisms like
plants or animals ever evolved on Mars, it is not impossible,
and perhaps, buried deep below the surface of the Red Planet
is black gold – petroleum formed from their ancient remains.
Mars is the most likely place in our Solar System where
humans might attempt an off-Earth colony, but it would be a
hostile new home. If people do settle there, they will find it
NASA/JPL
NASA’s Interior Exploration using Seismic Investigations, Geodesy and Heat Transport mission (InSight) will launch to Mars in 2016 to drill 30 feet into the Red Planet’s crust.
NASA/JPL
NASA's Curiosity rover detected fluctuations in methane concentration in the Martian atmosphere, currently being added to (sources) and removed from (sinks) Mars.
Richard Brounstein’s “What If?” column tests the limits of our
imagination – can the improbable or impossible be reality one day?
WHAT IF???
7
May 2015
bright. With modern telescopes, thousands have been ob-
served in other galaxies. And in the 1990s, scientists noticed
that very distant Type 1a’s were much further away than they
should be. Something was pushing them away faster. They
had discovered dark energy – the force that accelerates the
growth of our universe.
Looking at its scattered-light, scientists in 2008 verified
with spectroscopy that Tycho’s Supernova was a Type 1a
stellar explosion. Just as sound waves bounce off walls, a
star’s light bounces off dust and echoes, and we can actually
see the very same light that Brahe saw. “But what exactly did
he see?” posed Fisher.
A Type 1a supernova is the explosion of a white dwarf
star pushed to its limit – it’s Chandrasekhar Limit, that is. In
1930, twenty-year-old Indian student Subrahmanyan Chandra-
sekhar wiled away the hours on a train ride to Cambridge,
England by calculating the maximum mass for a white dwarf
to remain stable. Above 1.4 solar masses, a dense, white
dwarf would undergo gravitational collapse, and evolve into a
neutron star or a black hole. But before that happens, most
white dwarves blow up in a thermonuclear explosion. White
dwarves are essentially dead stars. Known as “degenerates,”
they are the last stage in life for most stars, like our Sun, that
aren’t very massive. Hydrogen fusion has stopped, helium
fusion to carbon and oxygen has ceased, and it has shed its
outer layers to form a planetary nebula. So, how can a dead
star explode? With a little help from a friend.
“Sometimes a white dwarf comes out of retirement,”
said Fisher. In a binary system, a white dwarf accretes matter
from a less massive companion, and it can gain enough mass
to begin burning carbon again. “A white dwarf is an inside-
out Sun,” explained Fisher, convecting on the inside and radi-
ating on the outside. As carbon burns inside, the interior of
the white dwarf ignites and propagates outward as a flame,
similar to lighting a match. This thermonuclear flame inciner-
ates the white dwarf. Huge amounts of energy are generated
in just a few seconds – even more energy than is created dur-
AAA Lecture (cont’d from Page 1)
CXC/M.Weiss
Type 1a supernovae occur in binary systems where a white dwarf accretes mass from a companion star. The dead white dwarf comes back to life as it gains mass, burning carbon until it detonates.
ing the Sun’s entire life cycle. The companion star should
survive the explosion, but often, it is nowhere to be found in
the supernova remnants, as with SN 1572. “What happened
to the companion? Where’d it go?” asked Fisher.
In March, the European Southern Observatory deter-
mined that a compact helium star called US 708 – the fastest
moving star in the Milky Way at 1,200 km/sec – was set in
motion not by our galaxy’s black hole, but by a Type 1a su-
pernova. Its trajectory suggests it had once been a red giant
companion to a white dwarf, flung far, far away from home by
a stellar explosion.
From trajectories, we may be able to locate more com-
panion stars. But there might be another reason why we can’t
find them. According to a “double-degenerate” model for
Type 1a supernovae, the white dwarf’s companion could be
another white dwarf. In this scenario, a less massive white
dwarf becomes the accretion disk for the more massive one.
When they merge, both white dwarves are incinerated in the
detonation. This would explain why so many companion stars
cannot be found, even when they should still be hiding in the
remnants of younger supernovae.
But very few double-white-dwarf systems have been
discovered. Two months ago, measurements by Japan’s Su-
zaku X-ray satellite revealed that the pre-explosion mass of a
supernova called 3C 397, which has no identifiable compan-
ion star, came from only one white dwarf. This was deter-
mined by nickel and manganese content in the cloud remnant,
“a fingerprint for the single-degenerate model,” said Fisher.
Looking for those dense elements, we can distinguish whether
a supernova came from a single-degenerate or double-
degenerate system. It would seem that both kinds do exist.
By the end of this decade, the Large Synoptic Survey
Telescope (LSST) in Chile, currently under construction, will
begin gathering light. It is designed to have a very wide, un-
distorted field of view, and one of its goals is to look for tran-
sient events like supernovae. With the LSST and better com-
puting technology in the near future, Fisher believes that the
progenitors for these very important Type 1a supernovae will
be found. “We’re going to crack the mystery within the next
five years, so come back soon!”
Sources: nytimes.com; astronomy.com; wiki.
CXC/M.Weiss
In double-degenerate Type 1a supernovae, both stars in the binary system are white dwarves, and both are annihi-lated in the merger.
8
In Remembrance Marion McMorris
In March, AAA sadly lost
its oldest and longest-running
member of AAA: Marion
McMorris (née Louis), age 98. A Brooklyn native, Marion at-
tended Erasmus Hall High
School and worked for the Be-
nevolent Society for Retarded
Children. She had been a mem-
ber of AAA for over 70 years.
In 1948, she organized and led
an observing field trip to Vassar
College, and while serving on
AAA’s Board in 1953, she orga-
nized a regular bulletin for
AAA’s Observing Group, a sup-
plemental to the Eyepiece called
Skylines. Marion, who suffered
a stroke in January, lived in Durham, North Carolina, but she
remained an active AAA member. According to her daughter,
Mary, she was alert up until the end and loved having the
monthly Eyepiece read to her. Learn more about Marion and
her husband, Leroy Sells McMorris, and the early days of
AAA in the article "A History of the First Forty Y ears of the
Amateur Astronomers Association" by Patrick Rizzo, which
can be found at http://www.aaa.org/articles/a-history-of-the-
first-forty-years-of-the-amateur-astronomers-association/.
May 2015
demonstration of his techniques in the hotel parking lot. Amer-
ican DSLR imager Jerry Lodriguss offered two excellent work-
shops, while Gordon Haynes from England presented a detailed
look at narrow band imaging and showed colorful images pro-
duced from different combinations of data.
NEAIC is serious about its presenters. “I’m out hunting
the Web for speakers. I look at Facebook, Astronomy Picture
of the Day, Cloudy Nights, various astronomy forums,” said
Moore, “I’m looking for the person who does the one picture I
haven’t seen yet.”
Moore and NEAIC co-Founder Mike Peoples also take
pride in presenting entry-level workshops for beginners, to help
grow the astro-imaging community. Peoples, an astro-imager
himself, is the manager of the astronomy and sport optics de-
partments at the Adorama camera store in Manhattan. In addi-
tion to helping coordinate the conference, Peoples brings in
camera manufacturers to set up booths and display the latest
imaging equipment at NEAIC. About 20 vendors showed off
their wares this year, spilling out of the conference room and
into the hallways.
After the NEAIC workshops ended, many participants
stuck around town that weekend for NEAF, the world’s largest
astronomy expo. During this huge, two-day event, the floor of
Rockland Community College’s main gymnasium was crowded
with rows of telescopes, cameras, books, and photographs.
Amateur astronomy clubs from all over set up booths. AAA
was situated in a prime location and well represented by many
volunteers – Rori Baldari, Siyu Tu, Katherine Troche, Sam B.
Hahn, Simon Cox, Marcelo Cabrera, Tom Haeberle, Tony
Hoffman, Christina Pease, Peter Tagatac, and Michael O’Gara
– who generously offered their time, as well as cookies and
snacks, to everyone who stopped by the booth. AAA’s Susan
Andreoli coordinated the shifts for both days.
Several of the NEAIC speakers also gave talks at NEAF,
including Matthew Penn of the National Solar Observatory at
Kitt Peak in Arizona. Penn described an ambitious new citizen
science project to take place during the total solar eclipse on
August 21, 2017: the Citizen Continental America Telescopic
Eclipse Experiment (CATE). The goal of Citizen CATE is to
make a continuous 90-minute movie of the solar corona for the
(NAIC and NEAF article, cont’d from page 1)
Stan Honda
Planetary imager Christopher Go of the Philippines presented to a packed house at the 10th Annual Northeast Astro-Imaging Confer-ence from April 16-17, hosted by the Rockland Astronomy Club.
duration of the event by enlisting members of the general public
to record observations from 61 locations in the U.S. along the
path of totality. That path won’t go through New York, but for
those interested in volunteering for Citizen CATE elsewhere,
check out https://sites.google.com/site/citizencateexperiment/
home.
April’s NEAIC and NEAF had a great deal to offer astro-
imagers and astronomy enthusiasts. The Rockland Astronomy
Club can be congratulated on another fantastic year. In case
you missed one or both of these great events, be sure to keep an
eye out for next year at http://www.rocklandastronomy.com/
index.html.
Stan Honda
Rori Baldari, Siyu Tu, and Katherine Troche represented AAA at its NEAF booth in April.
Photo Courtesy of Mary McMorris
AAA’s Marion McMorris joined the club in the 1940s. Here she is engaged in her favorite hobby. Marion passed away in March at the age of 98.
9
Sun. In the next few frames, I could see the inner corona and
several large, red prominences emerging from the Sun. I
turned on the bracketing setting, letting the telephoto camera
automatically shoot pictures at the set exposure, and I took
four over-exposed and four under-exposed shots in 0.7 stop
increments. The longest exposure I got was 1/40 sec, f11 at
ISO 400, because I forgot to reset the shutter speed to a lower
number. So, I wasn’t able to capture the large outer corona,
which is much fainter than the inner corona. But, the totality
images themselves looked great.
On the wide-angle camera, I had to manually change to
slower shutter speeds of 1/30 sec and even 1/8 sec (at f8, ISO
400). This involved a lot of guess-work; I checked the picture
on the camera screen once and then continuously slowed the
shutter down, hoping to get more detail in the foreground. At
that point, I was manually triggering both cameras while look-
ing up every few seconds for an unobstructed view of totality.
Somehow I managed to capture third contact on both
cameras, with the bright sun just beginning to peer around the
(Solar Eclipse Article, cont’d from page 5) Moon again. In the wide-angle shot, the Moon’s shadow is just
receding from the horizon at the southwest. A dip in the moun-
tains frames the Sun and Moon in the sky, and a line of eclipse
watchers can be seen standing in the snow along the bottom of
the photo. On March 21, Astronomy Picture of the Day posted
the shot – http://apod.nasa.gov/apod/ap150321.html – my first
photo to appear on the NASA-sponsored website.
As gratifying as it was to see my hard-earned photo ap-
pear on APOD, the real reward was actually seeing the total
solar eclipse in the magical Arctic land of Svalbard – an in-
credible experience I won’t forget.
For more photos of the total solar eclipse, visit
www.stanhonda.com/new-work.
May 2015
Explore night sky photography at
www.stanhonda.com
Stan Honda is a professional photographer. Formerly with Agence
France-Presse, Stan covered the Space Shuttle program. In his
“Focus on the Universe” column, he shares his night sky images and
explores his passions for astronomy and photography.
Submit your photography questions to stanhonda@gmail.com.
Stan Honda
Totality: 11:11 AM local time. Nikon D810 camera, 80-400mm zoom lens at 400mm. Exposure: 1/40 sec., f11, ISO 400.
Stan Honda
Third contact: Astronomy Picture of the Day (APOD). Nikon D800 camera, 14-24mm lens at 24mm. Exposure: 1/8 sec, f8, ISO 400, no filters.
10
Telescope of the Month The Byurakan Astrophysical Observatory in Armenia
Located on Mount Aragats, near the Armenian capi-
tal Yerevan, sits a major astronomical center of Soviet
science, the Byurakan Astrophysical Observatory (BAO).
In 1971, it was the site of the First International Symposium
for CETI research (Communication with Extraterrestrial Intel-
ligence), attended by Frank Drake, Carl Sagan, and prominent
scientists from various fields. Operated by the Armenian
Academy of Sciences, the BAO houses five telescopes, in-
cluding a 2.6m Cassegrain reflector and a 1m Shmidt camera.
Built in 1946, the BAO was headed by Viktor Ambartsumian,
a founding father of theoretical astrophysics – analytical and
numerical models direct observers to find data that will refute
a model or choose the best one. He is credited with inventing
the modern theory of gas nebulae and star shells, based on his
evaluations of the masses and spectra of novae ejecta. During
World War II, he invented the theory of nonlinear light diffu-
sion in turbid media, using his own Ambartsumian principle
of invariance – fluctuations in the brightness of the Milky
Way do not change with the location of an observer. In 1947,
he discovered stellar associations – large, loose groupings of a
relatively few young stars of similar spectral type. It has been
determined that 90% of all stars are born in stellar associa-
tions. In the 1950s, Ambartsumian’s concept of Active Ga-
lactic Nuclei stated that the bright centers of certain galaxies
expel huge amounts of mass, so they must contain some un-
known massive bodies. Observations of quasars and an un-
derstanding of black holes have made AGN now widely ac-
cepted. The bright nuclei of these active galaxies produce
excess emissions over various wavebands of light. In 1965,
another Armenian astronomer, Benjamin Markarian, conduct-
ed the First Byurakan Survey with the BAO’s Schmidt, which
was the largest telescope at the time to have a full aperture
objective prism. The Survey searched for a class of bright
galaxies that emit excessive ultraviolet radiation. Its optics
corrected for blue-violet, the color of their nuclei. The First
Survey discovered 1,500 of these Markarian galaxies; a Sec-
ond Survey expanded the search to include fainter objects.
Following the collapse of the Soviet Union in 1991, work on
the Schmidt halted, and the BAO fell on hard times. Since
the mid-2000s, cooperation from Russia has led to a program
to modernize and repair the Schmidt telescope. AMW
Sources: aras.am; .bao.am; wiki.
Celestial Selection of the Month The Dark Tower
The ominously named Dark Tower in the southern
constellation Scorpius is a Bok globule, which sounds far
more comical than scary. Bok globules are cold, dark,
dense clouds of gas and dust that form in contact with hot,
ionizing stars. They tend to be sites of stellar birth. They
were first dis-
covered in the
1940s by Bart
Bok, who de-
scribed them
as “similar to
insect’s co-
coons.” He
believed that
inside, gravita-
tional collapse
was making
new stars,
which beget
more and more
stars. It was-
n’t until 1990
that near infra-
red analysis confirmed that stars were forming within these
dark clouds. 40 light-years across, the Dark Tower is called a
cometary globule, because it resembles the shape of a comet
with its head and tail. Found 5,000 light-years away in the
Gum 55 nebula (RCW 113), its head faces the open cluster
NGC 6231, known as the Northern Jewel Box (out of frame
here). Intense radiation from the hot O- and B-type stars of
the cluster blows the globule’s dust to create its tail. The dark
cloud’s cold surface also warms, releasing hydrogen gas.
That gas is then ionized by the OB stars’ ultraviolet light,
creating the pretty red plasma of the HII emission nebula
glowing around the Dark Tower. Embedded within the dark
structure are beautiful blue reflection nebulae, where dust
particles scatter the short wavelengths of visible light from
hot, bright stars. AMW
Sources: wiki; apod.nasa.gov; annesastronomynews.com;
fromquarkstoquasars.com; skyimagelab.com.
May 2015
CALL FOR WRITERS
Do you enjoy reading the Eyepiece?
How would you like to see your name in print?
The Amateur Astronomers Association of New York’s journal Eyepiece is looking for dedicated writers to contribute articles covering lectures, seminars, and
observing events around town, as well as current topics in astronomy and astrophysics.
Interested? Please submit a short writing sample to Amy Wagner at editor@aaa.org.
Don Goldman
The Dark Tower in the constellation Scorpius is a cometary globule, a cloud of gas and dust with a shape that resembles the head and tail of a comet.
BAO
The Soviet era 1m Schmidt telescope at the Byurakan Astrophysical Observatory in Armenia.
11
A Classic Keeps Up the Good Work
By Luis Marcelo Cabrera
“Delightful” and “easy to read”
are words that come to my mind
when describing the latest edition of a
classic: Astronomy: A Self-Teaching
Guide, Eighth Edition by Dinah L. Mo-
che (John Wiley and Sons, Inc., 2014).
Since 1978, Moche’s books have
educated and entertained students, as-
tronomy enthusiasts, and those with a
spark of curiosity about the universe.
My first encounter was with the Sixth
Edition, which I borrowed from a friend
several years ago. I later came across the Seventh Edition in
educational settings, from informal talks to introductory astrono-
my courses. I was excited to delve into the Eighth Edition when
it reached my hands earlier this year. The new text is updated
with the current number of moons in the Solar System.
Moche covers every subject an astronomy beginner would
want to understand. The book is formatted as a self-teaching
guide with questions and answers placed strategically throughout
to anticipate a reader’s progress with the material. Each of the
book’s 12 chapters ends with a self-test to evaluate that progress.
At 388 pages, the book is packed with useful resources like star
maps, lists of stars, constellations, and Messier objects, as well as
definitions of astronomy symbols and constants, and the Periodic
Table of Elements. A colorful insert of astro-images enhances
the material, and websites are provided throughout the book as
further references, so one can easily explore a given topic more
deeply. Although the drawings and illustrations in the book are
in black and white, they work so well that the reader doesn’t
miss the use of color. In the Nook version, I found them to be
more effective than some of the full color diagrams found in
astronomy magazines for e-readers and tablets.
The text is easy to understand, and the descriptions of com-
plicated concepts are great for beginners as well as readers not
entirely new to astronomy. Moche’s writing has a special magic
that can make those complex ideas actually seem simple. The
book covers most aspects of astronomy, and the topics build on
each other in sequence from chapter to chapter. A more experi-
enced astronomy learner can jump around, browsing pages and
exploring topics at leisure. I found myself flipping right to ques-
tions that are often brought up at AAA events. Moche’s explana-
tions and examples are very effective and easy to remember. In
fact, I have come to rely on them. When fielding these ques-
tions, I am grateful to have a Dinah Moche answer at the ready.
Moche’s book also goes into topics that are often neglected
by astronomers but extremely useful to observers, like telescopes
and light, right ascension, declination, planetary motions, magni-
tudes, and celestial coordinates.
In the past, AAA has provided parents and educators with
copies of the Seventh Edition at its events. Their feedback was
in agreement that Moche’s book made some of the toughest top-
ics in astronomy easy enough to discuss over a cup of coffee. I
am happy to report that the new edition of the go-to guide I have
enjoyed for many years continues that excellent tradition.
May 2015
BOOK REVIEW
12
Dear AAA Members,
Don’t miss the last installment of the AAA Lec-
ture Series at the American Museum of Natural History
with the annual John Marshall Memorial Lecture on
Friday, May 1. Our speaker will be Jacqueline van
Gorkom from Columbia University, presenting "Gas
and Galaxy Evolution: From Voids to Clusters". Be
sure to check back in the fall for another excellent sea-
son of speakers.
Please join us at AAA’s Annual Spring Starfest at
Woodlawn Cemetery on Saturday, May 2. As usual,
there will be nighttime observing, raffles, and prizes.
We will start early with solar observing in the after-
noon. Be sure to check out the AAA website for details.
On May 8, AAA offers another special Astro
Answers with the presentation “New Horizons: Ex-
ploring Pluto,” hosted by Jaclyn Avidan at the Ameri-
can Museum of Natural History. Learn all there is to
know before the spacecraft’s historic arrival at the
dwarf planet.
Lastly, come meet your fellow club members at
the AAA Annual Meeting on May 21 at Manhattan
Youth, located at 120 Warren Street. Refreshments are
served beginning at 6:30 PM; the meeting will com-
mence at 7:30 PM. I look forward to seeing you there!
Marcelo Cabrera
AAA President
president@aaa.org
May 2015
Eyepiece Staff May Issue
Editor-in-Chief: Amy M. Wagner Copy Editor: Richard Brounstein
Contributing Writers: Richard Brounstein, Luis M arcelo
Cabrera, Tony Faddoul, Stan Honda, and Amy Wagner
Eyepiece Logo and Graphic Design: Rori Baldari
Administrative Support: Joe Delfausse
Printing by McVicker & Higginbotham
FRI, May 1
@ 6:15 pm AAA John Marshall Memorial Lecture at AMNH, M
“Gas and Galaxy Evolution: From Voids to Clusters” with Jacqueline
van Gorkom of Columbia Univ. in the Kaufmann Theater. (Enter 77th St)
@ 7:30 pm – 11 pm Next: Every Friday & Saturday Night
AAA Observing at Lincoln Center Plaza – Manhattan, PTC
SAT, May 2
@ 3 pm – 9:30 pm
AAA Spring Starfest at Woodlawn Cemetery – Bronx, PT
Take a tour of the Sun, Solar System, and universe at this annual public
event filled with raffles, prizes, and fun! AAA members lend their time,
telescopes, and expertise to share the wonder of urban astronomy. Solar
observing at 3 pm; Night sky observing at 6:30 pm. (Enter at the Jerome
Ave. entrance; Rain date: May 3)
@ 7:30 pm – 11 pm Every Friday & Saturday Night
AAA Observing at Lincoln Center Plaza – Manhattan, PTC
@ 9 pm – 11 pm Next: June 6
AAA Observing at Brooklyn Museum Plaza – Brooklyn, PTC
SUN, May 3 @ 1 pm – 3 pm Every Sunday
AAA Solar Observing at Central Park – Manhattan, PTC
(At Conservatory Water – “the model boat pond”)
TUES, May 5
@ 7:30 pm – 11 pm Every Tuesday Night
AAA Observing at the High Line – Manhattan, PTC
FRI, May 8
@ 6 pm AAA Astro Answers at AMNH, M
“New Horizons: Exploring Pluto” with Jaclyn Avidon. (Enter 77th St)
@ 8 pm Columbia Univ. Stargazing & Lecture at Pupin Hall, P
“Al Otro Lado del Espectro” with Alejandro Núñez. (In Spanish)
MON, May 11 @ 7:30 pm
AMNH Frontiers Lecture at the Hayden Planetarium, P
“A Planet for Goldilocks” with Natalie Batalha at the American Muse-
um of Natural History. Learn the latest in the hunt for exoplanets, in-
cluding those that may harbor life, with a mission scientist from
NASA’s Kepler Space Telescope. (Enter 81st St)
THURS, May 21 @ 6:30 pm
AAA Annual Meeting at Manhattan Youth, M
AAA Members dine and meet to discuss club business from the past
year and upcoming year and elect board members. (120 Warren St.)
TUES, May 26 @ 6:30 pm
AMNH Astronomy Live at the Hayden Planetarium, P
“Dance of the Planets” with Joe Rao. Explore the highlights of the
June 2015 evening sky, which will feature an array of bright planets.
(Enter 81st St)
FRI, May 22
@ 8 pm – 10 pm Next: June 5
AAA Observing at Floyd Bennett Field – Brooklyn, PTC
@ 8 pm – 11 pm Next: June 26
AAA Observing at Carl Schurz Park – Manhattan, PTC
SAT, May 23
@ 8:30 pm – 11 pm Next: June 20
AAA Observing at Great Kills – Staten Island, PTC
C: Cancelled if cloudy; M: Members only; P: Public event; T: Bring telescopes, binoculars.
For location & cancellation information visit www.aaa.org.
AAA Events on the Horizon A Message from the AAA President
The Amateur Astronomers’ Association of New York Info, Events, and Observing: president@aaa.org or 212-535-2922
Membership: members@aaa.org Eyepiece: editor@aaa.org
Visit us online at www.aaa.org.
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