THE SOUTHWORTH PLANETARIUM

70 Falmouth Street Portland, Maine 04103

43.6667° N 70.2667° W Altitude: 10 feet below sea level Founded January 1970

2021-2022: CXVIII

"There is no greater agony than bearing an untold story inside you."

-Maya Angelou

THE DAILY ASTRONOMER Wednesday, May 4, 2022

May 2022 Night Sky Calendar Part II

Named after Maia, the Roman goddess of growth, May marks the last full month of spring. (Up here, it marks the first half month of spring.) As we learned yesterday, the month of May ushers out the winter constellations while drawing the summer constellations into greater prominence. In other celestial matters, May 2022 will bring us the Eta Aquarid meteor shower, a gathering of the moon, Mars and Jupiter, and, of course the TOTAL LUNAR ECLIPSE on the night of May 15/16. As you might expect, this last event will take up most of the oxygen in this first part of the May 2022 night sky calendar.

FRIDAY, MAY 6: ETA AQUARID METEOR SHOWER PEAKS

Only active around the first week in May, the Eta Aquarid shower produces about 40 bright, fast meteors at its peak. Although it is not considered a major shower, the Eta Aquarids are noteworthy because of their progenitor comet: none other than the famous Halley's Comet. When one observes such a meteor, one is watching a fragment of Halley's Comet perish in a spasm of light. The best time to watch for this meteor shower is after midnight, the time when our part of the planet is turning in toward the densest part of the meteoroid stream.

Fortunately, the waxing crescent moon (28% illuminated) will set at 10:46 p.m. that evening.

SUNDAY, MAY 8: FIRST QUARTER MOON

TUESDAY, MAY 10: MOON NEAR REGULUS

One will see the waxing gibbous moon (66% illuminated) close to Regulus, the brightest star in Leo the Lion. The moon will appear to move to the north of this star.

THURSDAY, MAY 12, 2022: BRILLIANT ISS FLY-OVER

The International Space Station will pass almost directly overhead on the morning of May 12, 2022. The chart below shows the ISS path through the sky during this "fly-over" event.

Time-table:

4:21:50 a.m. The ISS rises WNW

4:27:16 a.m. The ISS attains its maximum altitude of 82 degrees. At this time, the ISS will also attain its maximum brightness of magnitude -3.9: just about as bright as Venus!

4:32:40 The ISS sets SE.

Although we'll see the ISS fly over dozens of times in May 2022, the May 12th early morning fly over will be the brightest of them all!

SUNDAY, MAY 15, 2022: TOTAL LUNAR ECLIPSE (PLATINUM EVENT!!!!) Tonight, the full moon will move through the inner part of Earth's shadow, a dark region known as the umbra.

First, the eclipse will occur on the night of May 15th. Actually, it will begin on May 15th and end on May 16th. Refer to the time table below.

May 15 - 9:32 p.m. PENUMBRAL ECLIPSE BEGINS

Earth's shadow is divided into two regions: the light, outer part of Earth's shadow, called the 'penumbra,' and the inner region called the 'umbra.' The penumbral eclipse begins when Earth first touches the penumbra. The moon passes completely into the penumbra before it reaches the umbra. Honestly, unless you're one of those mystical poetic types who can actually tell the difference between a whisper of a breeze and a caressing zephyr, you won't notice much during the penumbral part of a lunar eclipse. Perhaps the brilliant moon's pallor is rendered a few phantoms less vibrant, but even that is a stretch.

May 15 - 10:27 p.m. PARTIAL ECLIPSE BEGINS

This is when the 'action' starts. The umbra is the dark interior shadow. Once the umbral eclipse begins, we'll see Earth's curved shadow against the moon. We'll watch the shadow migrate across the moon until the moon is completely immersed in Earth's shadow.

May 15 - 11:29 p.m. TOTALITY BEGINS

Totality begins when the moon is completed inside Earth's umbra. The moon will not be wholly lost from sight. Instead it will appear reddish, because Earth's atmosphere scatters blue light, but directs red light into its shadow. (We see a blue sky during the sky because of this effect.) The eclipsed moon will reflect this reddish light back to us, producing the ominously named 'blood' moon. One effect that we think is absolutely magnificent is the 'spherical moon' phenomenon. During totality, the color differential across the moon's facade lends it a spherical appearance. The moon actually appears as a crimson sphere in space, as opposed to the full moon's usual disc-like appearance.

May 16 - 12:11 a.m. MAXIMUM ECLIPSE

When the distance separating the center of the shadow and the moon's center is at a minimum.

May 16 - 12:53 a.m. TOTALITY ENDS

At this moment, the moon starts its exit from the umbra. We will see a thin sliver of the moon emerging from the inner shadow.

May 16 - 1:55 a.m. UMBRAL ECLIPSE ENDS

For all intents and purposes, the show is now over. The moon completely leaves the umbra and appears, well, like a full moon again, except that it remains immersed in the penumbra.

May 16 - 2:50 a.m. PENUMBRAL ECLIPSE ENDS

The eclipse event is now technically over. Of course, the moon's brightness is hardly diminished during this last hour because the penumbra is so faint.

Part III tomorrow

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In honor of May 4th day:

STAR WARS ASTRONOMY

A LONG TIME AGO IN A GALAXY FAR, FAR AWAY
This famous opening line prompts the question: could alien life have existed a long, long time ago?   We know that advanced life forms cannot exist without an abundance of complex molecules that, themselves, are composed of "heavy elements," such as oxygen, phosphorous, carbon, and others.*      Only the simplest elements, primarily hydrogen and helium, existed during the Universe's infancy.     The first generation of stars manufactured the "metals," defined astronomically as the elements heavier than helium.   These stars, being the highly massive population III, would have exploded as supernovae, thereby enriching the galaxy with an infusion of all the heavy elements.     This chemically rich material would have then become incorporated into other star/planet systems. On these heavy element laden planets the first life might have developed. The life might have evolved from the simplest prokaryotic cells to a galaxy-dominating empire. We assume, based on Earth's evolutionary time frame, that such a process would have required at least five to six billion years.   As humans haven't yet become a star faring race, we haven't the faintest idea how long such a progression would require.   After all, humans haven't yet ventured more than a quarter of a million miles from Earth. We're a long way from zipping between star systems.

The upshot of it all is that the Universe might well have produced mighty empires in distant galaxies that have long since vanished. We can't know if they existed, of course, but we can at least be confident that the necessary chemical building blocks have existed in the cosmos for billions of years.

The assumption we've made is that we're actually now observing the "Star Wars" galaxy as it was when all that transpired on film was happening.   If it all occurred a billion years ago, the galaxy is a billion light years away from us.    Then, again, there is a slight possibility that we're over thinking it.

LASER GUNS
As impressive as these weapons appear, we certainly hope they weren't expensive, because they truly don't work well.     Let's assume you are surrounded by a doom of storm troopers,** but, fortunately, you're armed with a laser gun.   You fire indiscriminately at your assailants, some of whom deftly dodge the rays, while others are slain by them.    Then, of course, you realize: these accursed beams are moving very slowly!   A beam of light travels at more than 186,000 miles a second in a vacuum and at nearly the same speed in air. If the storm trooper can avoid the beam, it is traveling thousands of times slower than lasers actually travel.     It is true that a laser pulse can fry a nervous system and make short work of storm troopers, even though they are completely enclosed in the most expensive armor the Empire can buy.   However, someone should tell the Empire engineers to remove the anchors from the beams because the light is moving like its 145 years old and doesn't really care any more.

WARP SPEED
Remember that scene when Han Solo was piloting the Millennium Falcon and then floored it to light speed? Well, how could one forget!    The pinpoint stars rapidly elongated to luminous lines converging to the middle distance.    If I might include a brief personal recollection.   I remember my brother, Richard, took me to see the 1977 Star Wars movie and just before Han et al accelerated to warp speed, he nudged me and said, "Watch this!"    I did and was, of course, astonished and said, to the delight of nearby viewers, "Wow, Dic, tell him to do that again!"    Now, had I known then what I pretend to know now, I would have instead said, while pedantically waggling an index finger, "Now, Richard, you realize that if those oddly dressed people were actually traveling on board a vessel traveling at light speed, they wouldn't be able to converse because time stops at light speed.   The Theory of Special Relativity tells us that time dilates on any moving object and that dilation relates directly to the speed. The faster the vessel, the greater the dilation.   If the Millennium Falcon had achieved light speed, time would stop.   Of course, the ship's mass also increases with increased speed, so its mass would essentially become infinite at light speed, which would preclude it from attaining that velocity."

And, we agree....the "Wow, Dic, tell him to do that again!" was the far less annoying thing to say.

RULING THE GALAXY
Alexander the Great would have liked this: he would never have run out of  to conquer.   In the Star Wars Universe, the Empire ruled an entire galaxy with a particularly hard iron fist.     Such domination would have necessitated the development of a particularly advanced hyperspace travel and communication infrastructure.     Let's imagine that someone wants to govern the Milky Way Galaxy.   According to recent estimates, our one galaxy contains more than 200 billion stars and, perhaps, an equal or even greater number of planets.    Quite a lot of real estate to have under one's dominion. One would require untold trillions of minions to do one's bidding and one would also need the means by which to convey the latest dictates instantaneously to all your myriad underlings.     If you were constrained by light speed, you wouldn't be able to maintain order. Let's just say a planet full of troublesome upstarts on the other side of the galaxy starts to go all Libertarian on you and resists the Empire.    You decide to send them a placating message of "Shut up and deal with it!" Even if the message travels at light speed, it would require tens of thousands of years to reach them, by which time the original agitators will have long since perished. So, too, would you.

Of course, there is always the Von Neumann machine method.     An advanced alien race constructs a vessel capable of traversing great distances and self replication. As it travels through the galaxy, it visits various planets and mines raw materials from which it manufacturers components to construct a copy of itself. Once completed, this copy proceeds to also make copies of itself. These, in turn, would be self replicating so that after a comparatively brief time, perhaps 200 million years, Von Neumann drones could be swarming through the galaxy.     Let's be cheerful and further assume they've also been programmed to conquer inferior races (i.e. all of us) and, being incapable of empathy, have no compunction about slaying the disobedient.    Perhaps through the agency of these surrogates, a race could conceivably become both prevalent and domineering.   Good luck collecting the taxes, though!

Then again, maybe the Star Wars franchise is just brilliant science fiction designed to delight audiences, inflame imaginations, and enrich the movie studios. That is just fine by us because there is nothing more electric and elating than escapist escapades into the remotest hollows of outer space.

*The vast majority of life forms consist primarily of six elements: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur.   As we lack any knowledge of extra terrestrial life forms, we cannot know if these elements will be as predominant in alien beings.

**Yes, there are collective nouns specific to storm troopers and yes, I actually took the time to look it up and yes, somebody else took the time to make one up and then post it on line and yes, if you were a socially awkward geek type you'd also have plenty of spare time at night to learn collective noun words such as a doom of storm troopers, a shortage of dwarves, a debauchery of hedonists, a metamorphosis of ovoids, a wiggle of Elvis impersonators (you can't unsee that), a tabula rasa of empiricists and, G-d help us, a handful of palm readers.

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