SETI Pioneer Frank Drake Celebrates His 90th Birthday

This week, Dr. Frank Drake, the pioneer in the scientific search for intelligent life elsewhere in the cosmos and one of my favorite astronomers, turns 90. He has been a really important mentor in my life, with good advice at several crucial career points, and I want to wish him all the best on this occasion.
He is perhaps best known for the ”Drake Equation,” a formula for making estimates of the number of technological civilizations in the Galaxy that are capable of communicating with us. To read an article in which he wrote up “The Origin of the Drake Equation” (for a column I was editing at the Astronomical Society of the Pacific), go to: http://bit.ly/drakearticle
For my 2012 interview with Drake, where he reflects on his work over the years, see: https://www.youtube.com/watch?v=HPQz-kdaxNo&t=536s The accompanying picture shows us on that occasion, at the SETICon convention organized by the SETI Institute, where he and I have been on the Board of Trustees.
With all the reasons to despair of intelligent life here on Earth, I hope we can soon realize Drake's dream of finding it among the stars. A number of projects are carrying on the search he began, and a success would be a great present for his next birthday.

My Second Published Science Fiction Story Now Available Free On Line

 As some regular readers know, one my recent projects is writing short science fiction stories based on good astronomy. After a long learning period, two of my stories have now been published in science fiction anthologies. The second one, which is about exploding stars and music, just had its rights returned to me, and so I am happy to put it up free on the web for everyone's enjoyment at: 

https://www.researchgate.net/publication/310397794_Supernova_Rhythm 

After the short story, I have put a non-technical explanation of the science behind the fiction.

The accompanying photo is a NASA composite showing the remnant of Tycho's Supernova, a star seen to explode by the great astronomer Tycho Brahe in October 1604. In this image, blue and green colors shows what the remnant would look like if you had x-ray eyes, the yellow shows what it looks like in visible light, and the green shows the heat rays (infrared) coming from the object. Blended together, all the colors show where this remarkable "left-over"of a star that blew itself to bits is still glowing brightly more than 400 years later.

By the way, if you also want to read my first published science fiction story "A Cave in Arsia Mons" (about a surprising discovery on Mars), you can do so at: 

https://www.researchgate.net/publication/282914928_The_Cave_in_Arsia_Mons

My Talk to the Commonwealth Club on the Moon

The Commonwealth Club of California invited me to give an illustrated public talk about the Moon on the occasion of the 50th anniversary of the first human steps on our neighbor world. The video record is now available free on the Web, so if you are any of your friends (or students) are interested, you can find it at: https://www.commonwealthclub.org/…/astronomer-andrew-frakno…

I wanted to speak not so much about the astronauts and their journey (which so many other media and articles are covering in vast depth) but about the Moon itself, and what we now know about it, 50 years later. Hope you enjoy.

An audio-only version of the talk is also available as a podcast, at: https://www.commonwealthclub.org/events/archive/podcast/astronomer-andrew-fraknoi-50-years-our-first-step

The photo shows the Moon in front of a full Earth as seen from millions of miles away by the Deep Space Climate Discovery Spacecraft in 2015.

Total Eclipse of the Sun in South America July 2; Future U.S. Eclipses

Tomorrow, July 2, there will be a total eclipse of the Sun visible in Chile and Argentina. A live webcast is planned at: https://www.exploratorium.edu/eclipse

Another total eclipse will be visible from southern South America on Dec. 14, 2020.

Looking further ahead, an annual eclipse will be visible on a path that goes across the U.S. on Oct. 14, 2023.

And Apr. 8, 2024 another total eclipse will sweep across the U.S. from Texas to New England. For a clear map of this eclipse, see: https://www.greatamericaneclipse.com/april-8-2024

(Shameless plug: Dennis Schatz and I have written a children's book all about eclipses, called "When the Sun Goes Dark," for the non-profit National Science Teachers' Association Press. See: https://www.nsta.org/store/product_detail.aspx… )

A free app about eclipses, called "Totality" is available from astronomer Jeff Bennett, at: https://www.bigkidscience.com/eclipse/

[Our photo is by astronomer Rick Fienberg and shows a sequence of images before, during, and after a total eclipse.]

Government Shutdown Expands: Moon Goes on Furlough Tonight

In the above table, you can see the timing of tonight total eclipse of the Moon for all the North American time zones. Click on the image to see it bigger.

Don't worry about the first and last rows of the table. Just focus on when the partial eclipse begins (when the Earth's shadow first starts to move across the Moon) and when the total eclipse begins (the Moon is full covered by shadow and turns red.)

Remember, if there are clouds, this eclipse last a long time, so come back out after a few minutes and see if you can glimpse the Moon. Often the Moon plays hide and seek with layers of clouds, and patience will pay off.

Full details of the eclipse and what to watch for are here:
http://bit.ly/mooneclipse2019

Thanks to Sky & Telescope magazine for the table.  The composite photo below is by amateur astronomer and NASA educator, Brian Day.  Note the Earth's round shadow in the outer images and the coppery red color of the eclipsed Moon (the Earth's atmosphere bends red colors of light more effectively than other colors on to the shadowy face of the Moon.)

Heads Up: Total Eclipse of the Moon Sunday Evening January 20

On Sunday evening, January 20, there will be a nice total lunar eclipse (where the Earth’s shadow darkens the full moon) visible in all of North America. Since this is the day before Martin Luther King Day in the U.S., many students will not have school the next day and can stay up to enjoy the celestial spectacle with their families.

Total eclipses of the Moon are perfectly safe to look at, don’t require special viewing equipment, and are visible all over one hemisphere of planet Earth. Your eyes are just fine to see the show. This is quite a contrast with the total eclipses of the Sun, where viewing can sometimes hurt your eyes, special equipment is a big help, and the best show is only visible in a narrow path. As Bernie would say, the lunar eclipse is for the 99%, not just the special 1%!

A more detailed information sheet I put together (with questions and answers, plus the timing in each time zone of the continental U.S.) can be found at:
http://bit.ly/mooneclipse2019 

Here is wishing you a cloudless evening, and a few hours thinking about the heavens and not the craziness in Washington.

[Our beautiful photo is by Conrad Jung of the Chabot Space and Science Center, 2007]

Encounter with the Furthest Object Humanity Has Ever Explored

Tonight, the New Horizons spacecraft will fly by a chunk of ancient ice and dirt nicknamed "Ultima Thule." 4.1 billion miles distant from us, this small world, estimated at perhaps 20 miles across, is the the furthest object ever visited and examined by human technology. We should have first pictures and other information about it by Wednesday, when NASA plans a press conference.

The accompanying image shows an artist's attempt to draw this minor member of the zone beyond Neptune we call the Kuiper Belt. Pluto is also a member of this belt, but with far better property and voting rights than little Ultima. Several observations from afar have suggested that Ultima is elongated (maybe even two chunks that might just barely touch) and reddish. Its orbit indicates that it may well be very ancient, one of the first building blocks from which our solar system (the planets and moons that accompany the Sun) was assembled more than 4 1/2 billion years ago.

Moving at 32,000 miles per hour, and with sunlight only 1/2 of one percent as bright as it is at Earth, New Horizon's cameras will be put to the test to take pictures. The power (from radioactive materials) available to power the spacecraft is now only 190 watts! We will get within 2200 miles of the Ultima, closer than we got to Pluto with the same spacecraft in 2015.

New Horizons can either point at its target or at Earth. So it will at first send very little information and spend most of its time as it whizzes by pointing at Ultima. When it has gone by, it will point back to Earth and take 20 months to send the encounter data back to Earth (it's transmission rate is slow, but steady, much like this Facebook page.)

By the way, the term Ultima Thule means "Beyond the Known World"; it was term used on medieval maps to mark parts of our planet that were not yet explored and thus were veiled in mystery.  (It was a nickname suggested in a public naming contest run by the SETI Institute.)

Keep your fingers crossed that things go better 4 billion miles from Washington DC than they have gone at home! 

A New Selfie from Mars

NASA's InSight lander on Mars has sent back its first "selfie" -- a great mosaic of 11 images, taken by the color camera on the "elbow" of its robotic arm. You can clearly see the round solar panels (7 feet wide) which collect power for the lander, and, between them, the instrument deck for measuring weather, marsquakes, and other conditions on Mars. Eventually, the instrument package nicknamed the mole will try to dig a hole 16 feet deep and see how heat flows inside the red planet. It's terrific to see InSight's systems slowly being tried out and working so well.

Click on the picture to see it larger.

A Possible New Planet Around the Second Closest Star System to Earth

An international team of astronomers is announcing the possible discovery of a planet around the second closest star system to us, Barnard’s Star. A mere 6 light-years away, the star is a faint red dwarf which gives off only four hundredths of a percent of the Sun’s light energy. The planet, which could be as massive as 3 Earths, is orbiting at the same distance as Mercury is from the Sun, but is still colder than Saturn and unlikely to harbor life as we know it.

Since the closest star system to us also has a known planet in it, this discovery (if it is confirmed) would make it even more likely that planets are “more common than dirt” out there. Four planetary systems would then be known among the stars 10 light-years or closer. Some 2900 planetary systems (containing almost 4,000 planets) have now been found in our galactic neighborhood.

The new planet, which takes 233 days to orbit, was detected from the very slight “wiggles” that the planet’s gravity (as it goes around) gives to the motion of its star. The wiggles are so small that it took 20 years of observations, using special equipment on various telescopes around the world, to identify them. While it’s still possible that their combined observations have another explanation, the 63 authors on the paper announcing the planet have dug deeply into their data statistics and claim that the planet idea is the most likely explanation. Not all experts in the field agree that this is a definite detection. Instruments of the future, with better ability to detect tiny star wiggles, will ultimately decide if the planet is real.

Our image shows an artist conception of what the the “cold, hostile desert” surface of the planet around Barnard’s Star, with a temperature of -270 degrees Centigrade, might look like. (You will need to take your parka if you go.)

Need Listeners' Astronomy Questions for “Fraknoi’s Universe”

With veteran talk-show host and ABC-radio newscaster Gil Gross, we are starting a new series of podcasts to be called “Fraknoi’s Universe.” (It helps to have an unusual last name!)

The pilot episode (made last summer about the total eclipse of the Sun): https://districtproductive.com/fraknois-universe/ was a success on a number of CBS radio stations, and on the Web. So we are starting to record further episodes, discussing the latest news and discoveries from the worlds of astronomy and space exploration.

As part of the program, we’d like to answer general astronomyquestions from interested members of the public. If you have a question (focused on astronomy and space) that you’d like to ask, please e-mail me at:

foothillastroprof@gmail.com

 Be sure you include your full name and home town, so we can mention it on the air.

Feel free to pass this on to others interested in astronomy.

When the shows are ready, we’ll announce them here and on other social media. 

Thanks very much.

First Visitor from the Realm of the Stars Ever Found Is Oddly Shaped

Astronomers around the world have been observing a small but fast object that gives every indication of coming from some other star system. It's the first such "interstellar" visitor we have ever observed. And it's characteristics are quite unexpected.

Most astronomers expected the first such deep-space visitor to be a comet -- a chunk of icy material (which our solar system has in great abundance outside the orbits of the main planets.) But all the characteristics of this visitor argue against that idea. It didn't evaporate and develop a "tail" as it came closer to the Sun than Mercury. Any comet would have done that.

And it seems to spin in less than 8 hours. Something made of snowballs or ice might fall apart from such a fast spin. So it appears that our visitor is made of rock -- more like an asteroid and not like a comet. And its color is dark and reddish, like some asteroids we have seen from our own system.

Furthermore, its shape -- which we can estimate from the way the sunlight reflected from it changes -- is also odd. It appears to be much longer than it is wide. Our best estimate is a cigar shape (see the attached painting from the European Southern Observatory), perhaps half a mile long and only 80 yards in diameter. But it could also be a flat cylinder -- which reminds some people of the shape of the main body of the Starship Enterprise.

(Just to be sure, astronomers at the SETI Institute used their antenna array in Northern California to check if the visitor was sending any radio messages. Nothing was found.)

First discovered by a team led by Karen Meech of the University of Hawaii using a Hawaiian telescope, the visitor has been given a Hawaiian name: Oumuamua, which means "scout or messenger, arriving first" -- not a bad fit. Its scientific designation is 1I2017U1. The 1I stands for first interstellar object ever discovered!

When we found it on Oct. 19th, it was coming in fast from the direction of the constellation of Lyra. It's now going out at a speed of 86,000 mph relative to the Sun. It already crossed the orbit of Mars and will reach the distance of Jupiter in May 2018. Having been whipped around by the Sun's gravity, it will go out in a new and random direction, back toward the realm of the stars.

We expect that such visitors should be passing through all the time, but we haven't discovered them until now. With new surveys of small, dim objects in the sky soon getting under way, we expect to find a lot more small pieces from our own neighborhood -- and beyond. Stay tuned.

A Ring Around the Dwarf Planet Haumea

European astronomers have announced the first discovery of a ring around a dwarf planet. Dwarf planets are similar to Pluto, in that they are small and hang out in a zone with others of their kind. This one, Haumea, is beyond Neptune, taking 284 Earth years to go around the Sun.

The ring is very faint, but astronomers at the Institute of Astrophysics of Andalusia were able to find it when they saw Haumea cross in front of a star. The star’s light went out not only when Haumea crossed in front of it, but briefly before and after, indicating a ring was present.

All four of the giant planets in our solar system have rings, but this is the first found around a smaller planet. Its cousin Pluto definitely doesn’t have one, because we looked when the New Horizons probe went by it.

Haumea is named after the Hawaiian goddess of childbirth and has another oddity. It spins so rapidly – taking less than 4 hours for one spin -- that it doesn’t look exactly round, but more oval shaped. It’s the least round of any world we know bigger than about 60 miles across. It has two known moons, and now a ring too. The zone past Neptune, called the Kuiper Belt, is just getting more and more interesting.

(Our illustration is NOT a photo, just an artist's impression, based on what we have observed so far.)

New Hubble Image of Jupiter's Red Spot

Astronomers are eagerly awaiting new information about the Great Red Spot, the largest and most colorful storm in the atmosphere of the giant planet Jupiter. The Juno spacecraft just flew as close as 5600 miles over the Red Spot, and the information is coming slowly back to Earth. This giant storm is currently about 10,000 miles wide -- larger than the entire planet Earth -- although it is smaller than when the Voyager spacecraft flew by in the 1970's. Why it has been shrinking and why it's color is so vivid are mysteries planetary scientists are trying to solve. 

In the meantime please enjoy the attached Hubble Space Telescope image of Jupiter, taken on April 3, when the Earth was closest to Jupiter in its yearly orbit. The Red Spot is vividly clear on this wonderfully detailed image, taken from just a few hundred miles above our planet's surface.  (Click on the image to see it bigger.)

Eclipse Talk on YouTube and New Kind of Eclipse Stamp

   

We are exactly two months away from the eclipse of the Sun that is coming to North America on August 21, 2017. I gave an illustrated, non-technical talk on the eclipse in the Silicon Valley Astronomy Lecture series, and it is now available on YouTube at: https://www.youtube.com/watch?v=C2Folgs58oI The talk has lots of information and visuals on where and how the eclipse will be visible, how to watch it safely, and how the U.S. is preparing for the huge crowds that are expected in the narrow zone where the eclipse will be total.

   Yesterday, the U.S. Postal Service issued its first ever "thermochromic" stamp in honor of the eclipse. That means when you touch the picture, it changes. Clearly this is a stamp every science nerd...er...fan will want to have. You can get them at your post office or by mail through: https://store.usps.com/store/

   If you have not planned for the eclipse yet, now is the time to start thinking about where you will be on Monday, Aug. 21 and how you and your family or colleagues will observe the eclipse. In the video, I explain what is happening and give suggestions for safe viewing techniques. (Remember, any time any part of the Sun is showing, it's not safe to look at with just your eyes or sunglasses.)

   Thanks to grants from the Moore Foundation and Google, three astronomy colleagues and I were able to distribute 2 million safe eclipse-viewing glasses to public libraries nationwide. Check with your library to see if they are participating. The free booklet for libraries can be downloaded by anyone at: http://www.starnetlibraries.org/EclipseGuide/ 

The 'All-American' Eclipse of th

New Views of the Planet Jupiter

The first results are in from the Juno mission exploring the giant planet Jupiter, and there are many surprises.

Look at the beautiful image here (click on it to see it bigger), showing the first detailed views of Jupiter's south pole region. The colors are a bit exaggerated, but the structures are real. You are seeing giant cyclones and anti-cyclones, as large as 600 miles across! That's extreme weather the 11 o'clock news team doesn't even dream about.

I'll remind you that Jupiter is not a solid planet -- most of it is made of gas and liquid. Yet there is enough material inside the giant planet to make 318 Earths. Scientists did not know whether at its very center it might have a small solid core or not. Heat from within rises and various molecules move up and down, producing complex bands, zones, and storms in the upper atmosphere.

Additional Juno discoveries include that Jupiter has a bigger core than expected, but that it has a fuzzy-looking structure, as if it were not sharply defined. The giant magnet inside Jupiter that surrounds it with the most powerful magnetic zone of any planet was also found to be stronger than anticipated.

Furthermore, the northern and southern lights on Jupiter are excited not only by charged particles captured from space (as we have on Earth) but also, unexpectedly, from charged particles coming from inside Jupiter.

As usual, when we get better instruments focused on a world or process in astronomy, we find that some of our old assumptions or ideas will need to be revised. That's what makes astronomy so much fun.

Below is an image showing 14 days of the Juno spacecraft approaching and then moving further away from Jupiter's cloudy atmosphere. (Click on it to make it bigger.)

Bubbly Burp Tracks Giant Black Hole's Last Meal

Observations with a number of telescopes, including the Hubble, have now dated a kind of burp in the eating habits of the giant black hole at the center of our Milky Way Galaxy. It appears that about six million years ago, the central black hole "ate" a large cluster of stars and the neighborhood around it was energized by the process of the meal.

Black holes are regions where material (starting with dead stars) has collapsed so much, that nothing, not even light, can get out. The black hole at the center of our Milky Way now includes enough material to make more than 4 million stars like the Sun! It's what we call a "supermassive black hole" and lurks in the middle of our Galaxy like a giant speed trap for unwary stars or star groups that get too close.

As material is in the process of being "swallowed" by the black hole, it glows with desperate radiation, just before it falls in and disappears from view. A great bubble produced by the black hole as it ate its last serious meal has now been tracked by astronomers with much greater precision.

Just like the sound of the burp your uncle makes (after a heavy Thanksgiving meal) can travel through the dining room, so the bubble from this last meal can be seen traveling through the Galaxy like a giant expanding shell. The shell was probe by the Hubble as the light of distant objects raced through it and astronomers were able to measure the speed of the bubble's motion.

Six million or so years ago, it appears that a large clump of stars or gas (the raw materials of stars) was consumed by the black hole, making two "Fermi bubbles" in the Galaxy. Since then, the black hole has only been "snacking" -- tearing apart and eating an occasional star or random bit of gas. But no serious meal has made a big bubble from the mouth of the black hole since then.

Our diagram shows how in the six million years since that meal, the bubble has expanded at speeds of two million miles per hour and made a giant bubbles north and south of the black holes that extend for tens of thousands of light years. That kind of puts your uncle's last burp into perspective!

A Star With SEVEN Earth-like Planets

An international team of astronomers today announced that they have found a faint cool star that is surrounded by a system of seven planets, each of which resemble the Earth in size. Three of the planets orbits in what we call the "habitable zone" where water can be liquid and temperatures might be right for life.

The star, located about 40 light years away, is so faint and cool, it doesn't have a name like bright stars do. It's referred to by the name of the telescope that discovered it and given a number (TRAPPIST 1). Each of the planets is then given a letter from b to h. (See the diagram above.)

Note that the planets are all very close to their dim star, taking from 1.5 days to about 20 days to orbit it. (By comparison, the closest planet to the Sun, Mercury, takes 88 days to orbit.) Planets e, f, and g are the ones where the combination of a cool little star and close-by planet work out to make the temperatures potentially reasonable for life. This star enters the record books as the one with the largest number of Earth-like planets, and the largest number of candidate planets in the habitable zone.

Astronomers caution that the kind of star these planets live around (called an "ultra-cool red dwarf") tends to have a lot of "activity" on its surface when they are young. Great flares of energy and particles are given off in this kind of activity, which might flood the nearby planets with high-energy radiation. That might not be so healthy for the formation of life there until the star settles down to a more stable adult existence.

On the other hand, such low-mass stars (this one contains only 8% of the "stuff" our Sun has) tend to live much much longer than a star like the Sun, so there may eventually be a much longer opportunity for the planets to evolve their surfaces and atmospheres and give birth to life.

Another complication for planets so very close to their star is that their motion probably resembles that of our Moon in a crucial way. The Moon (and these planets) take the same time to orbit as to spin, which means they keep the same face toward the object they go around. So one side of each planet always faces their star and the other side is always in darkness. There is no day and night cycle on these worlds -- you either live on the star-facing side and have perpetual day or you live on the other side and have perpetual night. Only a significant atmosphere might make such a world more bearable and astronomers are using a variety of telescopes to probe whether these planets are surrounded by an air layer and how much and what kind of air they have.

Just to put the discovery in context, astronomers now know over 3,000 planets orbiting other stars, ranging from balls of gas and liquid much bigger than Jupiter, down to rocky balls smaller than Venus. Experts now estimate that perhaps half of the stars in our Milky Way Galaxy may possess planets, and many stars will have more than one planet, just like TRAPPIST 1 and the Sun do. The universe seems rich with planets of all kinds, making it more likely than ever that we are not the only form of semi-intelligent life in the cosmos.

Below is a little poster NASA created to show how the other planets in this system would look from the surface of one of them.

A Photo of the Earth and Moon from Mars!

   NASA has just released a remarkable image of the Earth and the Moon as seen from a spacecraft orbiting Mars. Our planet and Mars were 127 million miles apart when the photo was taken.

   The Mars Reconnaissance Orbiter (MRO) has been orbiting Mars since 2006, collecting very detailed close-up images and data about the surface of the red planet. In this case it was used to capture a photo of Earth and Moon with both bodies in the same frame. The image was taken at a time when the Moon was behind Earth as seen from Mars, so it shows the Earth-facing side of our natural satellite.

   Even at Mars' distance, the image of the Earth reveals continents. Australia is the reddish-brown feature in the center. Seeing ourselves as a tiny disk of light in the blackness of space can help remind us that we share a fragile and beautiful planet in our journey through space.

A Hidden Baby Galaxy in our Cosmic Neighborhood

An international team of astronomers, led by researchers at Japan’s Tohoku University, has just reported finding the faintest satellite galaxy ever seen orbiting our home galaxy, the Milky Way.  All stars are born in great islands or groupings of stars called galaxies.

Big galaxies like the Milky Way are surrounded by smaller “baby galaxies” (or satellite galaxies), some of which collide with it over cosmic times.  About 50 such galaxies are currently known to orbit our Milky Way – with the two “Magellanic Clouds” (discovered by Ferdinand Magellan’s crew) being the most famous of them.

Because many of the smallest galaxies are very faint, they are hard for us to make out.  Remember, we are inside the Milky Way, and so (as we try to look outwards) we always have to observe through the stars and star clusters of our own galaxy.  The faint baby galaxies can be hard to tell apart from clusters or groups of stars in the Milky Way itself. (This is why it’s hard to get a good photo of the Milky Way; we are inside it and so it’s like trying to take a selfie from inside your kidney.  The view is not so clear.)

Still, using the giant Subaru telescope (whose mirror is more than 24 feet wide), the team was able to find the faintest baby galaxy ever found, which is being called Virgo I (since we see it in the constellation of Virgo.)  At an estimated distance of 280,000 lightyears from us, Virgo I was much fainter than earlier surveys for our neighbor galaxies were able to reveal.

The whole Virgo I “dwarf galaxy” is only about 248 lightyears wide.  Compare that to the 100,000 lightyear diameter of the Milky Way! The Magellanic Clouds are estimated to be 7,000 and 14,000 light across.  So you can see that Virgo I really is just a baby. See the tiny smudge it makes on our accompanying image.

But if one such baby galaxy has escaped our notice until now, chances are many others like it may also be out there.  Some of our theories predict that major galaxies like the Milky Way should be surrounded by many more dwarf galaxies that we have seen so far.  Virgo I leads astronomers to think that more may be out there -- just waiting for bigger telescopes and more observations before they are discovered. 

Enjoy Sunday and Monday's "Supermoon" But Don't Fall for the Hype!

You may read stories in the media about Sunday evening’s or Monday morning’s full moon being a “supermoon.” And it is true that – by a slight amount – the full moon just before Monday’s sunrise will be the closest, brightest, and largest-looking full moon since 1948.

But the average person won’t notice much difference between this “supermoon” and an ordinary full moon. Clouds, smog, and human lights turn out to have a much greater effect on how bright a full moon looks to us. Still, if you look carefully under dark skies, you might convince yourself that the full Moon Sunday night and Monday before dawn looks a bit bigger and brighter than usual.

“Supermoon” is not an astronomical term. It was suggested by an astrologer and suddenly became popular in the media (who always favor superlatives) in 2011. We astronomers have been stuck with it ever since.

Why are some full moons bigger and brighter than others? It’s because the Moon’s orbit around us is not a perfect circle, but on oval shape called an ellipse. That means sometimes the Moon is a bit closer to us and sometimes it’s a bit further away. If a full moon happens just when the Moon is closer, we get a bigger and brighter looking full moon. The more precisely the closest moon and the full moon coincide, the better the super effect. Nov. 14th, the moon is full at 5:52 am Pacific time, while the moon is closest at 3:23 am. That’s a pretty close coincidence.

Does the “supermoon” have any significant effect on planet Earth. You may read predictions that there will be much greater tides or even earthquakes Monday morning. Don’t believe it! We have slightly stronger tides every time the Sun, Earth and Moon are lined up (which they are at every full moon). But the only time the supermoon will show itself in a significantly stronger effect on the shore is if we happen to be in the middle of a huge storm. And the Sun and Moon have no effect on earthquakes, which happen deep inside the Earth.

So if you happen to glance at the full Moon Sunday evening or Monday morning, enjoy the knowledge that the Moon is a bit closer to you. You may even howl at the Moon if the candidate of your choice didn’t get chosen in our recent elections. But don’t add the “supermoon” to your list of things worth worrying about.

(Photo of the Lick Observatory with the Moon behind it by Rick Baldridge of the Peninsula Astronomical Society.  This was taken with a special lens to enlarge both the observatory and the Moon.)