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Founded January 1970
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"Astronomy? Impossible to understand and madness to investigate."
-Sophocles
THE DAILY ASTRONOMER
Monday, December 5, 2016
Week 14 Night Sky Calendar
We think we have solved the "dearth nadir" issue: the name we apply to those weeks when we don't really have many truly noteworthy events to discuss on our weekly sky calendar. Every week from now until at least 2267, we shall feature one constellation in each of our night sky calendars. That way, we'll be able to cover almost all of the night sky throughout the school year! This is a perfect week to begin this new tradition, as shall only feature four celestial events in this calendar.
This week's featured constellation is the somewhat obscure, but still charmingly cute,
Lepus the Hare. This funny little rabbit literally cowers in Orion's shadow. Mythologically, this beleaguered animal mostly runs, trying desperately to evade Orion and his voracious hunting dogs, Canis Major and Canis Minor. In some star charts, Lepus is depicted as slain quarry and lies pathetically at Orion's feet. In others, the fleet footed Lepus runs scared, but remains uninjured. Lepus is also associated with the "rabbit in the moon," the animal that some moon admirers see against the moon's face. This perception of a hare is a good example of the strange psychological phenomenon called "pareidolia." (See "From the Catacombs of Infinite Knowledge.")
Lepus the Hare: the tormented rabbit pursued by both
Orion the Hunter and his hunting dogs, Canis Major and Canis Minor
Image by Astro Bob
Lepus the Hare rises in the early evening and remains visible throughout the night. Although it doesn't captivate like Orion or dazzle like Sirius, Lepus the Hare is a gentler character within the crowded winter firmament.
MONDAY, DECEMBER 5: MOON 2.9 DEGREES NNW OF MARS (BRONZE EVENT!)
Venus overshadows Mars considerably. Venus shines so brilliantly that sky watchers will often seek out Venus and ignore Mars. In fact, Venus is so prominent, it even insinuates itself into paragraphs that pertain to other planets. Those who want to find Mars can easily do so tonight, as this rust-coated orb loiters low below Selene this lovely evening. As the moon will be 33% illuminated, one will experience no difficulty seeing Mars despite the moon's close proximity.
WEDNESDAY, DECEMBER 7: FIRST QUARTER MOON
SATURDAY, DECEMBER 11: SATURN AT SOLAR CONJUNCTION
Were we to observe the solar system from an aerial (or, perhaps, celestial) perspective, we would see Earth and Saturn at either side of the Sun. The technical term for this configuration is "superior solar conjunction." as the planet is on the Sun's far side relative to Earth. A planet that has moved between Earth and the Sun is said to be in "inferior solar conjunction." Only Mercury and Venus can ever be at inferior solar conjunction.
Were we to observe the solar system from an aerial (or, perhaps, celestial) perspective, we would see Earth and Saturn at either side of the Sun. The technical term for this configuration is "superior solar conjunction." as the planet is on the Sun's far side relative to Earth. A planet that has moved between Earth and the Sun is said to be in "inferior solar conjunction." Only Mercury and Venus can ever be at inferior solar conjunction.
Speaking of which
SUNDAY, DECEMBER 12: MERCURY AT GREATEST EASTERN ELONGATION (20.8 DEGREES FROM THE SUN)
We review the elongation rule: when an inferior planet is at eastern elongation, it is visible in the western evening sky. When an inferior planet is at western elongation, it appears in the eastern morning sky. Mercury, being the closest planet to the Sun, never appears to stray from our parent star. Its maximum possible elongation is 28 degrees. This elongation is almost 21 degrees.
We review the elongation rule: when an inferior planet is at eastern elongation, it is visible in the western evening sky. When an inferior planet is at western elongation, it appears in the eastern morning sky. Mercury, being the closest planet to the Sun, never appears to stray from our parent star. Its maximum possible elongation is 28 degrees. This elongation is almost 21 degrees.
PLANET WATCH:
MERCURY (Host constellations: Sagittarius-Ophiuchus)
The first world peeks up in the western evening sky. This apparition favors southern observers, but Mercury remains visible low in the southwest for northern sky watchers. Mercury will be at greatest eastern elongation on December 11th, but at inferior conjunction on December 28th. Mercury will vanish around the third week of December. VERDICT: We would advise you to venture out during the first half of December to find Mercury. The elusive world vanishes late this month.
VENUS (Host constellation: Sagittarius) PICK PLANET!
People wonder why Venus is such a prima donna when she receives the coveted "pick planet' diadem almost every month. Venus enjoys the advantage of being the brightest planet, so whenever it appears it will invariably outshine it planetary cohorts. This month Venus shines brilliantly as the western evening sky star. VERDICT: Easy to find if you're outside in the early evening. Look west and just behold the spectacle.
MARS (Host constellation: Capricornus - Aquarius)
Here's an interesting observational exercise: observe Mars in the western evening sky throughout December. One will notice that Mars is setting around the same time each night. Mars has been setting around 9:30 p.m. each night this autumn because Earth and the red planet are moving in such a way as to make their positions relative to each other nearly constant. VERDICT: Not only can you see the red planet, you can almost set your watch by it. What's not to love?
JUPITER (Host constellation: Virgo)
Rising earlier each morning, Jupiter is the only pre-dawn planet visible to the naked eye. The fifth sphere serves as a the brilliant eastern beacon one can easily see provided one ventures outside a couple of hours before sunrise. VERDICT: The perfect planet for joggers, dog walkers, and those accursed few who always arise with alacrity before the alarm blares,
SATURN (Host constellation : Ophiuchus)
We're sorry to say that we have to bid Saturn adieu, at least for awhile. The ringed world vanishes into the dusk, destined to return to the pre-dawn sky by late December. Saturn is in solar conjunction on December 11th. VERDICT: Don't bother to seek out Saturn until just before the New Year's celebrations.
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FROM THE CATACOMBS OF INFINITE KNOWLEDGE
"Patterns and Pareidolia"
(Dedicated -posthumously- to the shadow professor, who would most certainly
consider the following information to be a laughable disaster.)
Look at this crater
Do you see the smiley face?
Galle crater on Mars (Image by the Viking 1 orbiter.)
Perceiving a face where none exists is a perfect illustration of "pareidolia," the tendency of humans to observe human or animals features in inanimate objects that bare only the slightest resemblance to humans or animals. This "smiley face" consists of a series of mounds with the Martian "Galle Crater."
Let's regard what is arguably astronomy's most famous example of pareidolia:
The Man in the Moon:
"The Man in the Moon" Image by
We think we're seeing a man's face imprinted on the lunar surface. Instead, we're actually observing "maria" next to the lighter lunar regions. Their relative placements suggest an irregular face complete with hooked nose, wide eyes and a gaping mouth.
Pareidolia is our mind's way of seeing discernible objects in Rorschach tests, hearing secret messages in songs played backward and populating a star-speckled sky with a menagerie of fantastical creatures. Cognitive psychologists would associate this tendency to imagine people and animals in our environment with the evolutionary instinct to detect prey and predators in an ever changing world. The romantics would instead insist that the highly fertile human imagination delights in projecting life in places it doesn't actually exist. Be it evolution or imagination. pareidolia is the secret function of the mind that gave rise to the same constellations that adorn our sky today.
We end with two more beautiful examples of pareidolia: the Horsehead Nebula in Orion and the eerie "Martian face."
Horsehead Nebula: Martian face:
Image by Ken Crawford Image by Viking I lander
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© 2016 Edward Gleason