Planetarium Newsletter - February 2018

Cosmic Curiosities

“For my part I know nothing with any certainty, but the sight of the stars makes me dream.”
~ Vincent Van Gogh, Dutch Artist

Cosmic Oxymorons

Hopefully, you’re not “clearly confused” by the “seriously funny” cosmic oxymorons that follow, but it’s a “definite maybe.” I’ll give you “even odds.” It’s my “only choice.”

Bright Night
winter circleNighttime used to be dark. With the advent of electricity, the night is not so shadowy anymore. When serious stargazers talk about a “bright night,” they’re talking no lights except for the stars above – in other words, getting away from city lights.

Winter is a great time to escape the city and go see an awesome starlit sky. A great place to start is the Winter Circle, a rounded path of bright stars in the constellations of Orion, Taurus, Auriga, Gemini, Canis Major, and Canis Minor. In February, these brilliant stars can be found due south an hour or two after sunset. So get out the lawn chairs or plop yourself in a snowbank, but make sure the Moon isn’t full or near full; the Moon’s intense brightness can act be as intrusive as a city streetlight.

Frozen Star
Stars are hot. The surface of the Sun is 10,000°F, and way down at the core temps swell to 27,000,000 degrees Fahrenheit.

So what’s a “frozen star”? The answer is a black hole! That was an early name for this supreme gravity giant.

black holeRecall Einstein and his discovery about how gravity works—his general theory of relativity. Mass bends, or warps spacetime. The more mass you have, the steeper the gravity well.

A black hole is formed by the death of massive star—much larger than the Sun. The star runs out of fuel, with no outward pressure to hold it up; it collapses upon its dense core and explodes as a supernova, but the tightly packed core is still there. It gets smaller and smaller, denser and denser, until it becomes frozen for any viewer outside the star. Its light can’t escape from its incredibly dense surface. If one was outside watching near this imploding star, she or he would never see the star implode all the way. It becomes a “frozen star.” The viewer no longer sees a star -- black holes are black because gravity is so strong its last gasp of frozen light is incredibly red-shifted (stretched).

For more on black holes, check out NOVA’s “The Black Hole Apocalypse” with host Dr. Janna Levin. >>

Empty Space
NASA-HS201427a-HubbleUltraDeepField2014-20140603_0.jpgPhotos from deep space are stunning. Billions upon billions of stars are in this Hubble Deep Field image of distant galaxies.  It looks like space is anything but empty. But that isn’t why “empty space” is a science oxymoron?

The universe is mostly empty. Envision one tiny snowflake in the volume of the Earth. That’s the density of the entire universe. There’s not much of anything between huge galaxies, between the mammoth stars in the galaxies, between the planets orbiting the stars. But there is something. Well, two things. . . .

There are a few hydrogen atoms in every cubic meter between the galaxies. That’s not a vacuum, but it’s awfully close. Remember atoms are tiny; one grain of salt has a quintillion atoms. Numerically, that’s 1,000,000,000,000,000,000 atoms!

Near empty space is also stirring with quantum vacuum fluctuations. This is when particles appear and reappear at random, seemingly out of nowhere. It is an energy change in an unpredictable point in space. It is both brief and temporary. These fluctuating energy fields are the result of quantum mechanics, the subatomic world of protons, electrons, and photons. The behavior of this invisible micro-universe shapes technologies we live by today.

Nothingness is real. “Empty space” doesn’t exist anywhere.


Solar Eclipse—from the Moon

eclipse from the moonOur lunar eclipse is the Moon’s solar eclipse. If you somehow escaped to the Moon on January 31, you would have seen the Earth cover the Sun. You would have a seen a red circle surrounding the Earth—an affect caused by its atmosphere bending sunlight into its spectral color. Red light is bent the most, far enough to reach you on the Moon.

No one is living on the Moon to witness this solar eclipse, but NASA does have a space ship there— the Lunar Reconnaissance Orbiter, or LRO - -and it is operated by solar power. To keep it running smoothly during last month’s solar eclipse (from the Moon), NASA engineers switched it to battery power so crucial instruments kept functioning.

For more general eclipse information, see the Journal Sentinel article about the Super Blue Blood Moon, featuring Bob Bonadurer. >>


Romancing the Stars

rts posterOur Planetarium’s annual Valentine’s Day show Romancing the Stars is set to play again on February 10 and 14. It’s a “light-hearted” look at the night sky and the universe. The program showcases beautiful ways the universe reveals itself through science discovery and art creativity.

A few times, the show will blend art and science together. Take the old song, Twinkle, Twinkle Little Star. The familiar words come from a 19th-century English poem called “The Star" by Jane Taylor. The song comes from an anonymous French melody that was later arranged by several composers, including Amadeus Mozart.

Cecilia Payne Goposchin The science twist to this song started in 1925 when astronomer Cecilia Payne-Gaposchkin figured that hydrogen is the main ingredient in a star. In her spectroscopic analysis, Dr. Payne proved that hydrogen was vastly more abundant than the other elements that were discovered in the Sun’s spectrum.

This led to a poetic rewrite of the Twinkle song:

Twinkle Twinkle little star,
I don't wonder what you are;
For by spectroscopic ken,
I know that you're hydrogen;

Who says science can’t have a little fun?

(These new lyrics are credited to Lewis Fry Richardson or Ian D. Bush.)


Michigan Meteor

Michigan-meteorite-Todd%20Slisher_0.jpgMeteors hit the Earth everyday. While most burn up as a "falling star," many survive their fiery path through the atmosphere to hit the Earth as a meteorite. In fact, it is estimated over 1,000 meteorites, weighing about one pound or more, fall to the Earth every year.

On Tuesday night, January 16, 2018, a meteor raced across the sky. It was seen by people across the upper Midwest, including many sightings from Wisconsin. But it was most spotted in Michigan --  where it exploded. Many heard the sonic boom a few seconds after  the bright flash. (Thunder travels slower than lightning.) If you saw it, it was a breathtaking, heart-pounding event, to say the least.

A colleague of mine, Todd Slisher from the Longway Planetarium in Flint, MI, tracked down where meteorites that survived the explosion might have landed. Lo and behold, Todd and his staff found a few small meteorites.

If you ever see a bright meteor, please report it to the American Meteor Society. Click on the "Report A Fireball" link and share your sighting to learn more about the "shooting stars" above.

To find out more about the Michigan Meteor, see the Fox 6 New report. >>

Sky Sights

Feb7-9 sky

Mars and Jupiter have separated quite a bit since their January conjunction. However, red Mars is aligning with red Antares in the south sky before sunrise. To add a 3D perspective to these two red celestial sights, the light from Mars takes about 10 minutes to reach your eyes. The light from the star Antares takes about 620 years! Watch the Moon orbit by on the mornings of February 7-9. Its light takes 1.3 seconds to travel to Earth.

February 16-18 sky

Venus is back. Well, sort of. You have to be persistent and try to catch it shortly after sunset. You definitely need a clear path to the western horizon to spot the 900°F world. Let the Moon be your guide on the nights of February 16-18. Though brilliant, Venus will be a challenge. Binoculars will help.

February 10-12 sky

Saturn rises about two hours before the Sun on February 1, and about 4 hours on February 28. Observe the ring jewel just above the “Teapot,” the nickname for Sagittarius the Centaur. The Moon will help you locate Saturn in the predawn skies of February 10-12.

Mercury is not visible all month.

Star Map

Download the February Star Map.  

Sign Up

See the Universe through a telescope! Join one of the Milwaukee-area astronomy clubs and spot craters on the Moon, the rings of Saturn, the moons of Jupiter, and much more.

Send an e-mail to Planetarium Director Bob Bonadurer at and place 'subscribe' in the subject line to receive the Starry Messenger and monthly star map.

Follow Bob on Twitter @MPMPlanetarium