Blue Moons, Blood Moons, and Super Moons: Separating Fact from Fiction

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[Total lunar eclipse. Courtesy NASA]

Prepare to be inundated with lunacy this week, thanks to three interesting configurations of our nearest celestial neighbor. Wednesday the 31st is the second full moon of January, making it the so-called “blue moon” (as in “once in  a blue moon”). But just how rare is a blue moon? Not very, if you consider that the time between two consecutive full moons is about 29.5 days, and all months except February have more than 29.5 days in them. For example, March 2018 also has two full moons.

The “blood moon” descriptor refers to a total lunar eclipse. When the sun, earth, and moon line up in that order in a straight line, the earth casts a shadow on the otherwise full moon. Because the red portion of sunlight refracts or bends through our atmosphere, the full moon doesn’t turn black but a coppery or bloody red. While it can be a startling sight to those who aren’t expecting it (I remember being scared to death as a child when I saw a lunar eclipse during a late night potty break), there is nothing bloody or gruesome about the event. On average one or two total lunar eclipses occur each calendar year. The January 31 total lunar eclipse will not be visible from here in Connecticut, as the moon will be setting as the eclipse begins. Our next chance to see a “blood moon” will be January 21, 2019.

Well, what about the so-called “super moon?” This refers to the full moon looking larger than average. Because the moon’s orbit around the earth is not a perfect circle, when the moon is at its closest point to earth (called the perigee) it looks 14% larger than when it is at its farthest point (called apogee). When this happens at the time of full moon, you might notice that the moon looks a little bit brighter than average. There is no scientific definition of a super moon (because it’s not really something that scientists care about, to be honest), but one running definition on the internet is that it is when the full moon occurs within a few days of perigee. So how rare is this? Considering that the first full moon of January 2018 (which occurred on New Year’s Day) was also a “super moon,” you have your answer.

Putting all three of predictable, cyclical configurations together into one event, however, is just a tad more rare. The last “blue-blood-super moon” was probably in 1866 (again, depending on your definition of “super moon”). So if you want to take this opportunity to go outside and gawk at dear old Luna, please be my guest. Just don’t howl, because you might be mistaken for a super blue werewolf!

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Perihelion and Palantiri: A Reflection on January 3, 2018

[Earth’s orbit (Courtesy NASA); J.R.R.Tolkien (Courtesy  The Tolkien Society]

Given the weight of the stories burying your social media on January 3 this year (including “bombogenesis”), you might have missed two less sensational annual events. At 12:35 AM EST, the Earth passed closest to the sun in its orbit, a point called perihelion (“around sun”). The actual time of perihelion varies a little bit each year, occurring some time between January 2-4. As you can see from the above diagram, we are not that much closer to the sun in January than we are at the farthest point (around July 4-5), called aphelion (“from sun”). A common misconception is that it is the shape of the earth’s orbit that causes seasons – being closer causes summer and being farther away causes winter. This misconception is fed by diagrams in science textbooks that greatly exaggerate the shape of our orbit, drawing it as an elongated ellipse rather than the rather more circular shape it actually has. The seasons are instead caused by the 23.5 degree tilt of earth’s axis.

The second annual event that was widely publicized on my social media was the 126th birthday of author J.R.R. Tolkien (January 3, 1892September 2, 1973), best known for The Hobbit and The Lord of the Rings. Among Tolkien fans it is a tradition to raise a toast to Tolkien at 9 PM local time on January 3 and proclaim “The Professor!” You might be wondering why I have included Tolkien in an astronomy blog. What many readers of Tolkien’s works miss is that he has a plethora of (often fairly accurate) references to astronomy in his fantasy! From the moon runes of The Hobbit to the various references to the sun, moon, stars, eclipses and more in The Lord of the Rings and his grand mythology The Silmarillion, Tolkien’s use of astronomy in his fantasy reveals his impressive knowledge of the night sky. Tolkien certainly wasn’t the first or last fantasy writer to integrate the night sky into his fantasy world, but unlike his friend C.S. Lewis, Tolkien felt it important to get the astronomy “right.” In fact, when he considered revising his unfinished mythology in the last decades of his life, he toyed with completely revising it to avoid trying to describe a mythological creation of the sun and earth, and used the then-current hypotheses concerning the formation of the moon as his guide.

So as you can see, January 3, 2018 gave this astronomer two reasons to celebrate. January 4, on the other hand, is just giving me an astronomical amount of snow to shovel….

When you wish upon a… piece of Halley’s Comet?

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Have you ever heard the superstition that you should wish upon a falling star? If you do that this week, you might just be wishing upon a piece of Halley’s Comet burning up in our atmosphere! Falling or shooting stars have nothing to do with stars. Instead, what scientists call meteors are flashes of light caused when a tiny piece of a comet enters our atmosphere and burns up. Imagine your car driving into a swarm of insects and watching them go splat on your windshield. That’s not a bad analogy for the earth running into a swarm of meteoroids, debris liberated by a comet as it orbits the sun. When earth passes through the orbit of a particular comet (which, for any particular comet, will occur at the same time each year), many of these meteoroids burn up, creating a meteor shower. A meteor shower is named not after the comet whose particles create it, but rather where in the sky the meteors seem to radiate from, or the radiant. The brightest constellation in the region usually lends its name.

We are currently in the midst of the Orionid meteor shower, whose radiant lies between Orion’s bright shoulder star Betelgeuse and the bottom stars of Gemini (see above). Depending on how the meteoroid field is configured (for example, the size and number of particles, and the width of the meteoroid field), a meteor shower can last for a few days up to a few weeks, but there is usually a narrow window where we hit the densest part of the stream and hence see the largest number of meteors per hour. This year the Orionids are expected to peak in the predawn hours of Saturday, October 21.

The Orionids are certainly not the best meteor shower of the year (at peak you might only see 20 per hour, and each meteor is not particularly bright), but it has a unique romantic charm due to the identity of its parent comet, Comet P/Halley, or as most people know it, Halley’s Comet. While the comet itself won’t be in our neighborhood again until 2061, each year we actually get two meteor showers from the material it left behind on previous journeys around the sun – the Orionids in mid-October and the Eta Aquarids in early May.

If you find yourself up before dawn this week, why not take a peek out your window in the direction of Orion, and see if you can make a wish on an Orionid – mine will certainly be to be alive when Halley’s Comet returns in 2061 so I can become a member of the Halley’s Comet two-timer club!

 

It’s the end of the world – again…

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… if Internet sources are to be believed (which they aren’t, but more on that later). Friday September 22 marks the first day of Autumn in the Northern Hemisphere, and Frodo and Bilbo Baggins’ birthday (for you fellow Tolkien fans), but it is the day after that has some hunkering down in their bunkers waiting for the beginning of the end.

According to one David Meade, this Saturday marks the countdown (conveniently of an unknown duration) to the end of Planet Earth. His “evidence” is the fact that September 23 marks the 33rd day after the solar eclipse (itself superstitiously considered an omen of the end) and that a number of the planets appear relatively near each other in the sky on either side of the sun, centered on the constellation Virgo. According to this individual’s personal interpretation of Revelation, this is a “clear” sign that the end is nigh. How will the actual end come about? According to Meade and other doomsday soothsayers who are piggybacking on this pseudoscience train wreck, the infamous (and apparently invisible to all astronomers) rogue planet/alien spacecraft “Nibiru” is finally on its often-claimed-but-never-observed supposed collision course with Earth.

Sigh. And I thought I was done with this after December 21, 2012 passed with a whimper and not a bang.

Let’s BRIEFLY debunk this, point by point. Please consult the embedded links for more information.

  1. The total solar eclipse on August 21 was not a harbinger of anything. There have been many total solar eclipses before (some with paths very similar to the one we enjoyed in the US) and there will be many more to come – until, in the distant future, the moon has slowly drifted far enough away from the Earth to no longer cover up the sun and cause a total eclipse. That will be a sad day indeed!
  2. While several planets do appear in a nice arrangement on either side of the sun (called a conjunction), there is absolutely nothing unusual about this. The fact that this is happening in the constellation of Virgo is also common. Nothing to see here folks, move along….
  3. Nibiru (sometimes called Planet X) is a figment of the imagination of one Zechariah Sitchin that was co-opted by various Internet alien conspiracy theorists and is equal parts bad astronomy and bad archaeology. There is zero evidence for its existence. Nada. Nothing.

    I-am-not-saying

Having said this, is it possible that the end of the world will be brought about through the influence of outer space? Actually I’d say the odds are 100%, but billions of years from now when the sun swells up into a red giant and turns the inner solar system into a rather unpleasant inferno. But in the meantime, we all have to go to work, pay our taxes, clean the litterboxes, and do the dishes. Life is too short to waste it worrying about pseudoscience. Instead, unplug from the Internet for an hour, go outside, and enjoy the real night sky without worrying that Planet Earth has a large red bull’s-eye painted on it. Like Twinkies, our expiration date is FAR in the future.

Reliving the Total Solar Eclipse

[Pinhole projections of the partial phase as well as the diamond ring after the total phase of the August 21, 2017 solar eclipse as seen from Marion, IL.]

Viewing a total solar eclipse is an extremely emotional experience, whether it is your first (in Jess’s case) or your fifth (in Kris’s case). We attempted to shoot a Facebook Live video with a cellphone of the minutes before totality until the internet connection cut out about halfway through totality. Although the visual portion is questionable at best, the audio gives you an accurate portrayal of the raw emotion that comes with witnessing a total eclipse after the years of planning, hundreds or thousands of miles of travelling, and nail-biting hours of wondering if the clouds will thwart all your hard work. Enjoy!

— Kris Larsen and Jessica Johnson

[Note: although the video is set as Public, it may not play on certain browsers]

Eclipse is Life-changing Experience for CCSU Alumna

 

[Jessica Johnson looking excited at 4:30AM on the bus to see totality; Diamond ring photo by Justin Motta]

Editor’s note: Jessica Johnson, CCSU alumna, posted the following to Facebook shortly after experiencing her first total solar eclipse. She graciously allowed us to share it with you

Words cannot describe what I have just experienced. It was dodgy early on and we drove almost 4.5 hours this morning to get out of the way of a nasty frontal system. We made it to Marion, IL and only had to bribe a few towering cumulus clouds to leave. I have never seen an eclipse before and I still don’t know if I am composed enough to describe it or even process what I have just witnessed. Seeing the total eclipse, corona, and everything else associated with it has rendered me speechless (which doesn’t happen too often). It was like an amazing dream and it was worth the wait. I just sat there and cried; staring at something that was so beyond what pictures or stories could ever give. If there was ever a time or an experience where I was physically/emotionally reminded that I was a part of something so much larger than myself this eclipse exceeded it and happily reminded me of the star dust in which I was born and will return to. Just so wonderful and awe inspiring, I am still emotional and will remember this for the rest of my life. Thanks to Kris Larsen for making this a reality for me. I can’t wait for the next one! I have no pictures because I wanted to just experience it, but I have friends who will share pics with me and I will share with you [See above picture from Justin Motta].

— Jessica Johnson, CCSU Class of 2016

What to do with those eclipse glasses now

[NASA eclipse glasses donated to the Burlington Library by NASA Solar System Ambassador Kris Larsen; empty box that once house the 1000 pairs of eclipse glasses Kris Larsen bought and donated to the public for the eclipse]

Now that the Great American Eclipse is over, what do you do with those eclipse glasses? Given the pains many of you went through to get them, it seems a shame to just discard them. You can put them in a safe place until the April 8, 2024 eclipse (which will be 90% partial in Connecticut, and total in parts of New England and New York state). If you do this, you should examine them for any holes or defects BEFORE the 2024 eclipse (in case you need to get new pairs). You can always use them to view large sunspot groups. Only large groups are seen with just eclipse glasses and the eye, so it will not be an everyday event. To monitor sunspot activity, I recommend the Spaceweather website.

If you want to pass on to someone else the excitement you felt at observing the eclipse, you can donate your glasses (if they are in good condition) to Astronomers Without Borders, who will redistribute them to schools in South America for the next two total solar eclipses. Please follow the directions on their website.

Of course, you might just hang on to them as a memento!