Tag: john mcmahon

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Free Astronomy Magazine – March-April 2023 Issue Available For Reading And Download

Above: Technically, it could be worse. Just give it some time. From the World Atlas of the Artificial Night Sky Brightness. Image generated by David Lorenz, djlorenz.github.io/astronomy/lp2020/

The most recent issue of Free Astronomy Magazine (March-April 2023) is available for your reading and downloading pleasure at www.astropublishing.com (and facebook).

On the cover: View of Hollywood and Los Angeles from Mulholland Drive, slightly overexposed to show the orange haze that envelops the city at night. Photo by Mike Knell

The highlight of the issue is Michele's article "The Fermi paradox – many solutions, no certainty." This discussion extends his lengthy streak of articles on the topics of exobiology, technosignatures, SETI focus, and simple statistics by including a recent reading list of books published on the topics from which we might all glean insights into what the current state of the fields are as of the early 2020's (historians, or those aliens themselves, can someday revisit our thoughts on the topic and wonder how we managed to be so prescient/way-the-frack-off at this moment in time).

The lowlight of the issue concerns the state of light pollution and the "we can't seem to get there from here" state of our transition to LEDs. "Stars are disappearing faster and faster" is not only technically true due to the observed acceleration of the expansion of the universe, but also true down here on Earth with the continued proliferation of nighttime illumination (I assume this is correct, as we don't get out much at night given the ages of the kids in the house). Not enough of us are fortunate to have a John McMahon in our midst promoting proper lighting and pushing for lighting ordinances. I lament the apparent demise of selene-ny.org (now defunct, but the group and site left its mark as a source of information online – wikipedia, slideshare, sky&tel, The Astronomical League) and can only hope you consider visiting the International Dark-Sky Association website and giving the astronomically-more-friendly lighting fixtures list a once-over before renovating.

Browser-readable version (and PDF download): www.astropublishing.com/2FAM2023/

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"Upstate NY Stargazing In October" Article Posted To newyorkupstate.com And syracuse.com

The fourth article in the series "Upstate NY stargazing in October: Prominent constellations of summer and winter visible on Autumn nights" is available for your reading and critical review at newyorkupstate.com and syracuse.com. The editors are still having a bit of fun with the word arrangement in the headline (I suspect the newest version was selected to get rid of the double "in" – but can't speak to the seasonal capitalization preferences – I trust in my editors), but everything else is going fairly smoothly.

star-4jpg-11365d07d678b3d4

Mars to find other. Click for a larger view.

I lament the lack of any mention of the Orionid Meteor Shower, which won't be impressive anyway thanks to the Moon, but should still have been included for monthly completeness. What would have been included in the article is provided below:

Meteor Showers: Orionids, Oct. 2 – Nov. 7, Peaking Oct. 20

Meteor showers are the result of the Earth passing through the debris field of a comet or asteroid. As these objects approach the warming sun in their long orbits, they leave tiny bits behind – imagine pebbles popping out the back of a large gravel truck on an increasingly bumpy road. In the case of meteor showers, the brilliant streaks you see are due to particles no larger than grains of sand. The Earth plows through the swarm of these tiny particles at up-to 12 miles-per-second. High in the upper atmosphere, these particles burn up due to friction and ionize the air around them, producing the long light trails we see. We can predict the peak observing nights for a meteor shower because we know when and where in Earth's orbit we'll pass through the same part of the Solar System – this yearly periodicity in meteor activity is what let us identity and name meteor showers well before we ever had evidence of what caused them.

The name of each meteor shower is based on the constellation from which the shooting stars appear to radiate – a position in the sky we call the radiant. In the case of the Orionids, the meteor shower radiant appears to be to the north/above of the belt and left shoulder of Orion, which rises from the east after 11 p.m. this month. The meteor shower itself is provided to us by Halley's Comet, and is the best of the meteor showers associated with Halley's debris field.

How to observe: Sadly, the Moon will be prominent in the late-night/early-morning sky during the days around the Orionid peak, making for a far less impressive display. The Orionids are not known for their impressive counts either, with 10 to 20 meteors per hour expected.

Orion marks the position of the meteor shower radiant, meaning the meteors themselves will seem to shoot roughly from the east to the west. To optimize your experience, lie flat on the ground with your feet pointed east and your head elevated – meteors will then appear to fly right over and around you. Counts and brightness tend to increase the later you stay out, with peak observing times usually between midnight and 4 a.m. The swarm of tiny particles is distributed broadly in orbit, meaning some people may shooting stars associated with the Orionids anytime this month.

Also, kudos to friend and fellow space trucker Prof. John McMahon for one orientational catch – the following:

Starting around mid-October, Jupiter will peak above the Western horizon just after 6:30 a.m.

should read:

Starting around mid-October, Jupiter will peak above the Eastern horizon just after 6:30 a.m.

The ability to iterate with the newspaper after providing the full content is perfectly encapsulated in a Charlie Rouse comment about Thelonious Monk in "Straight, No Chaser" – which I totally understand.

2016oct5_charlierouse"You know that you got to play correctly the first or second take or that's it. He would take it anyhow. You mess up, well that's it. You know, that's your problem. You have to hear that all the rest of your life."

For interested parties, this article also marks the second (and final) official mention (to the best of my knowledge) of our upcoming MOST/TACNY/CNYO hosting of International Observe The Moon Night on Saturday, October 8th. At present, the weather is looking less-than promising for even lunar observing, but plans are underway to handle the crowd either way.

If it rains Saturday night, then I recommend the following:

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Some Light Science Reading. The Constellations: Pegasus

As first appeared in the September 2010 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle (PDF).
Constellation Map generated with Starry Night Pro 6.

The Constellation this month is one light on interesting binocular and telescope objects but heavy in mythology and Naked Eye observing. To the Babylonians, the stars in this region also (or first) took on the shape of a horse known as MUL.ANSHE.KUR.RA. To the Greeks, sometimes a horse is not (just) a horse (of course, of course). The Greek mythology surrounding the winged horse Pegasus is, to say the least, involved and undecided. There are several pages discussing the mythology of Pegasus, which I refer you to in the interest of local brevity.

The torso of Pegasus is composed of a "Great Square" of stars that is very easy to see and is very often pointed out to visitors at this time of year at Darling Hill. This asterism (simply any grouping of stars that are not officially constellations) lies to the right (or south) of the Andromeda Galaxy (M31), one of the great views in the Autumn skies. As the scope is pointed in this direction anyway for a good block of time during Public Viewing sessions, the walk through some of the nearby Constellations (Cassiopeia, Perseus, Andromeda, Pegasus, Cepheus) reads like a Cliff Notes version of both Clash Of The Titans movies (unless John McMahon is running the presentation, in which case you're guaranteed a much better show). In the modern definition of the Constellations, the south-most (or upper left corner) star belongs instead to the Constellation Andromeda (but anyone staring at this part of the sky would be hard pressed to be struck more by the "Great Triangle" of Pegasus than the "Great Square" of Pegasus).

There are only two significant (and visually accessible) objects within Pegasus (the Constellation, that is) for the binocular and telescope viewer at Darling Hill. The first of these is the appropriately named Pegasus Cluster (M15), an ancient globular cluster clocked at 13.2 billion years of age. This cluster appears as a smaller version of M13 in Hercules, as captured by our own Stu Forster in the September 2008 Member Gallery and shown below. The second object is a far more difficult find, the very unique spiral galaxy NGC 7742 (below). The presence of a prominent ring in this galaxy (or, more specifically, the absence of pronounced spiraling from the center of the galaxy out to the edges) is a point of unexplained inquiry in modern astrophysics.
M15, photo taken by SAS member Stu Forster.
NGC 7742, image from the Hubble Heritage Team (AURA/STScI/NASA/ESA).

The most curious content on the wikipedia page for Pegasus involves the nontrivial amount of discussion about the reinterpretation of its connectivity by one H. A. Rey in, specifically, his book The Stars — A New Way To See Them. Rey's goal in this book is to redefine connectivity of some of the Constellations to make them a bit easier to see as the mythical beasts they are known for. For Pegasus (see below), Rey has eliminated any mention of Sirrah (or Alpheratz, as it's known within Andromeda), using the Great Square as a Great Triangle that marks the above-the-shoulder wings over the trapezoid torso (with the rest of the limbs along the southern edge of the Constellation). Upon inspection, his reinterpretation looked more to me like one of the drawings of The Man In The Yellow Hat who, along with Curious George, is perhaps the more famous of the illustrated characters created by H. A. Rey.
A new view of an old constellation, or The Batman In The Yellow Hat.

I'll admit I'm mildly ambivalent about the redefinition of Constellation connectivity. On the one hand, the Constellations are one of the oldest memes in human history among all societies (extant or extinct) and, to that end, connectivity has meaning as a way of marking out specific arrangements that have largely stood the test of time. The consistency of connectivity also provides a way to reduce the memorization fatigue that comes from having to see groups of stars in slightly different ways (clearly, one arrangement is easier to know and explain than several). This is of further significance when one uses Constellations as a specific guide to locating Messier (or other) objects. If I tell you that "M15 is on an almost straight line about 1/2 the distance of the two stars that make up the snout," you really have to trust that we're seeing the same horse!

On the other hand, there are many amateur astronomers who use Constellations largely as tools for finding smaller objects (with or without a knowledge of their history) and, as we are a species that excels at pattern recognition (how many flying faces and hippopotami can you see on a partly cloudy afternoon?), anything that makes life easier for you the observer (especially on cold nights when observing time is at a premium) should be added to your observing arsenal. H. A. Rey's interpretation of Pegasus connectivity might cloud just how pronounced the Great Square is (so you have to then present this Constellation with an addendum!), but it certainly does look more like a complete flying horse than the common artistic rendering of only the front half (clearly the side you'd want to have over you anyway given both choices).

Any way you look at it, it's still safe to assume that the winged horse must have been the most efficient way to travel in the ancient world. It certainly speeds up a good plot.

Clear skies, Damian