Subzero sun and a glimpse into the future

The sun rises through a bank of lake fog on Lake Superior near the Lester River on a bitter cold Thursday morning here in Duluth, Minn. Photo: Bob King

It wasn’t easy to feel the sun this morning with 19 below zero and a sharp northwest wind. No matter what the season, the sun’s brilliance remains the same, but you’ll strain to sense the warmer side of its personality on days like today. When the thermometer scrapes bottom in my town, Lake Superior exhales foggy breath just like people do. We call it lake steam or ice fog. Colder air blowing over the warmer open water suddenly drops in temperature; the water it’s carrying condenses into millions of wispy vapors. The swirls combine into clouds that rise into a tidal wave of steam in the distance. Raw, menacing, ethereal – pick your adjective. We love the apparition and consider it one of the many intangible reasons we choose to live here.

Photo of the sun taken at noon CST today by the Solar Dynamics Observatory. Several sunspot groups are visible including the lively 1401. Credit: NASA

After a period of doldrums, solar activity is picking up again with several picturesque and magnetically active sunspot groups dotting the sun’s face. In particular, Region 1401 has a busy, complicated mix of magnetic polarities (north and south magnetic poles) that’s been responsible for an ongoing series of flares. Once the group rotates more directly into our line of sight, we might see some effects on Earth. Meanwhile material from a January 16 coronal mass ejection (CME) is expected to touch our planet starting late tonight through the 20th. That means an increased chance for northern lights for observers at higher latitudes. If you live in the northern U.S. or southern Canada, it’s worth checking the northern sky both nights.

The Ring Nebula in the constellation Lyra is a classic example a planetary nebula. The remaining white dwarf is at center is the size of Earth but contains 1.2 x the mass of the sun. Credit: NASA/ESA

The sun is a middle-aged star with about five billion years of an active, exciting life remaining before it runs out of nuclear fuel. In the year 5,000,000,001 A.D. – give or take – the sun will sheds its outer layers to reveal a carefully kept secret – a tiny, compressed core called a white dwarf star. Though only as big as the Earth, a white dwarf is twice as hot and so fantastically dense that a teaspoon of the stuff would weigh as much as an elephant. Surrounding the dwarf will be a butterfly or ring-shaped cloud of gas astronomers call a planetary nebula. The name comes from its resemblance to the round shape of a planet.

The scenic cloud are the remains of the sun’s outer layers that will be expelled by powerful stellar winds during its tumultuous transition to white dwarfdom. Every time we observe a planetary nebula through our telescopes, we see the sun’s distant future.

ESO's Visible and Infrared Survey Telescope for Astronomy (VISTA) captured this unusual view of the Helix Nebula, a planetary nebula located 700 light-years away. The left picture was made through infrared filters. The telescope's infrared vision reveals strands of cold nebular gas that are mostly obscured in visible images of the Helix. Click to enlarge. Credit: ESO/VISTA/J. Emerson

European astronomers released a brand new photo today of the Helix planetary nebula in the constellation Aquarius taken in infrared light. The main ring of the Helix is two light years across and glows due to excitation from strong ultraviolet light emitted by the white dwarf at center. Each of the fine strands radiating from the nebula’s center span the size of our solar system and is composed of hydrogen molecules. To learn more about the Helix, please click HERE.

Assuming the Earth survives until the time the sun becomes a white dwarf, we’ll still revolve around it as always, but what we call “sun” will be only a pinpoint of white fire in a twilight-dark sky.

Father-daughter-Jupiter conjunction, aurora video and more

The thin crescent moon will pair up with Antares, the heart of the scorpion tomorrow morning at dawn. This is an ideal time to see the earthlit portion of the moon. Created with Stellarium

Mid-January. It’s cold here in northern Minnesota. While I wouldn’t pass up a cozy hour next to the wood stove, I’m drawn outside on even the bitterest of clear nights for yet another look at the winter stars. Jupiter’s still high in the southwestern sky and you can’t beat Orion charging up from the east. Shoot a line through his three belt stars toward the horizon and you’ll run right into the sky’s brightest star, Sirius.

Last night, while I peered through the telescope under a dark, rural sky, my daughter called me from downtown Minneapolis. Her sky was clear too, though orange and sapped of starlight. We shared the only “star” the two of us could both see at the same time – Jupiter. Like a communications satellite, the planet connected us across the miles.

Tomorrow morning there’s a nice conjunction of the thin crescent moon and Antares, the brightest star in Scorpius. Only a sliver of moon will be lit by sunlight. The remainder – the dusky, gray disk – glows from twice-reflected sunlight called earthshine. Some of the light reflected from our shiny planet bounces off into space, is picked up by the moon and then reflected back to our eyes.

Because the moon returns reflected rather than direct sunlight, earthlight has a dim, ghostly quality. All you need is an open view to the southeast around 6-6:30 a.m. at the start of morning twilight and the willpower to stand out in the cold to see it. I wake up very quickly when I step out the door in January. Coming back inside a warm house never felt better after you’ve gazed at the winter sky.


Time lapse sequences of photographs taken with a special low-light 4K-camera
by the crew of expedition 28 & 29 onboard the International Space Station from
August to October, 2011. Credit: Image Science & Analysis Laboratory,
NASA Johnson Space Center

I’ve posted aurora videos taken by the astronauts on the International Space Station before, but they’ve typically been brief. This one is five minutes long and features not only the quivering lights but cool flybys of cities and flashing thunderstorms. If you’re more in the mood to stay indoors tonight, this is for you. In order of appearance on the video are:

1. Aurora borealis pass over the U.S. at night
2. Aurora borealis and eastern U.S. at night
3. Aurora australis from Madagascar to southwest of Australia
4. Aurora australis south of Australia
5. Northwest coast of United States to Central South America at night
6. Aurora australis from the Southern to the Northern Pacific Ocean
7. Halfway around the World
8. Night pass over Central Africa and the Middle East
9. Evening Pass over the Sahara Desert and the Middle East
10. Pass over Canada and Central United States at Night
11. Pass over Southern California to Hudson Bay
12. Islands in the Philippine Sea at night
13. Pass over Eastern Asia to Philippine Sea and Guam
14. Views of the Mideast at night
15. Night Pass over Mediterranean Sea
16. Aurora borealis and the U.S. at night
17. Aurora australis over Indian Ocean
18. Eastern Europe to Southeastern Asia at night

Witnessed fall of Tissint Mars meteorite stirs excitement

A fragment of Tissint, the newest Martian meteorite to land on Earth, photographed on January 4 this year. It's covered in glistening black fusion crust created from melting of the outer surface layer during its fiery fall through the atmosphere. The last Martian meteorite seen to fall was Zagami in 1962. Credit and copyright: Abderrahmane Ibhi

A meteorite from Mars is a rare bird indeed. There are only about 60 known. A witnessed fall of a Martian meteorite is rarer still. The last time it happened was on October  3, 1962 in Nigeria when the 40 lb. Zagami meteorite landed about 10 feet away from a farmer who was chasing cows from his field. Fifty years later another piece of Mars came zinging through the sky, this time in Morocco.

At about 2 a.m. local time July 18, 2011 nomads and military personnel south of Tata, Morocco were awakened by sonic booms and a bright light from a large fireball. One eyewitness reported that the meteor turned from yellow to green and split into two pieces. Three months later in October, nomads found fresh, black fusion-crusted stones about 30 miles south of the village of Tissint. French meteorite hunter Luc Labenne was guided to the site of the fall by local meteorite hunters. He gathered up several samples and sent two grams worth for testing to Brigitte Zanda and Violaine Sauter at the National Museum of Natural History in Paris. They determined the crust was very fragile and fresh, good indications that it fell recently. Labenne then sent more pieces to an American researcher who confirmed their Martian origin.

This Tissint fragment from the Macovich Collection of Meteorites displays a beautiful black crust contrasting with a pale interior dotted with several dark crystals. The cube is 10mm across. Click image to see more. Credit: Darryl Pitt

The meteorite was officially named Tissint this week by the Meteoritical Society, but you might still see earlier references to its informal names Tata, Tanzrou and Foumzgit on some online sites. Either in the air or when it hit the ground (probably both), the new space rock shattered into many small fragments with weights ranging from about one gram to 987 grams. Few complete stones were found in the approximately 7 kilograms or 15.4 lbs recovered. The interior is pale gray dotted with occasional olivine crystals. As you might expect, the discovery and sale of pieces have been hot topics in both the meteorite collecting community and among scientists eager to study one of the freshest Mars rocks they’ll ever get their hands on.

Tissint is an igneous rock called a shergottite, named after the Shergotty meteorite that fell in India in 1865. Shergottites crystallized from hot magmas on Mars between 150 to 500 million years ago and were later ejected into space by large meteorite impacts. Their most likely sources are the young volcanic regions of Mars like the vast Tharsis Plateau, home to Olympus Mons, the biggest volcano in the solar system.

Rocks at the Mars Pathfinder landing site. Although covered by red iron oxide dust, the rocks themselves are gray. Credit: NASA/JPL

Most meteorites are 4.5 billion years old and date from the earliest days of the solar system, when asteroids were colliding and coalescing to form the planets. So while shergottites’ ages sound old, they’re very young by planetary standards and could only have formed relatively recently on a volcanically active planet other than Earth. That plus their particular chemical makeup and the trapped gases they contain that match those measured by the Viking and and other Mars landers clinch their Martian connection.  Shergottites come in several varieties; ones rich in pretty green olivine like this one are classified as olivine-phyric types.

A 147g Tissint meteorite with spectacular fusion crust and slightly oriented shape. Credit and copyright: Chladni's Heirs

You might think meteorites from Mars would be red – or god forbid, green – based on the planet’s overall color, but they’re far more drab. The red is iron oxide dust blown by Martian winds across the planet. It coats everything, but the rocks themselves are gray, mostly volcanic rocks.

Dr. Carl Agee, director of the Institute of Meteoritics at the University of New Mexico in Albuquerque, describes glassy melt pockets in Tissint, perfect for holding trapped gases and other Martian morsels. Melt, a sign of heating from impact and shock, will help tell us the story of the meteorite’s past – its catastrophic excavation, long journey through space and fiery delivery to Earth.

Best of all, a freshly-fallen stone has minimal weathering. This is truly pristine material. Whatever researchers find when they drill deep inside the new Tissint meteorite, whether that be signs of water or organic compounds, it’ll be the real deal from Mars, not contamination from Earth’s sticky hands.

For more on Mars meteorites, click HERE for the complete list and HERE for in depth information.

Milky Way white as the driven snow, scientists say

The bright Milky Way crosses the summer nighttime sky. A team of scientists recently determined our galaxy's color. Photo: Bob King

What do you suppose the Milky Way’s color is based on what you’ve seen with your eyes? If you guessed white, you’re dead on. A team of astronomers in Pitt’s Kenneth P. Dietrich School of Arts and Sciences announced last week the most accurate determination yet of the color of the Milky Way Galaxy: “a very pure white, almost mirroring a fresh spring snowfall.”

It seems obvious, but it’s really not easy to figure out the overall color of something you’re inside of or surrounded by. Looking out my window here in northern Minnesota, I might be tempted to call the overall color of the Earth gray, but I know better. What the team did instead was flip through the 930,000 galaxies images taken by the Sloan Digital Sky Survey and identify those that had qualities very similar to the Milky Way. In particular, they examined the total numbers of stars and the rate at which the galaxies were creating new stars, which are both related to the brightness and color of a galaxy. They figured the Milky Way should then fall somewhere within the range of colors of these matching objects.

The Milky Way-like galaxies known as SDSS J083909.27+450747.7 has properties which closely match those of the galaxy we live in and may be as close as astronomers can get to a view of the Milky Way as seen from outside. CREDIT: Brittany McDonald (McMaster University), Armin Rest (Space Telescope Science Institute), and Jeffrey Newman (University of Pittsburgh)

Jeffrey Newman, Pitt professor of physics and astronomy, described the overall spectrum of light from the Milky Way galaxy as being very close to the light seen when looking at spring snow in the early morning, shortly after dawn. You might also liken the color to the word that’s always been staring at us in the galaxy’s name: milk.

Astronomers classify galaxy colors broadly into two types – young ones that have a bluish color because they’re hatching lots of hot blue stars thanks to their abundant supply of dust and older red galaxies with more evolved stars. Big blue stars burn their fuel quickly and flame out while relatively young, while many of the smaller stars are either reddish or evolve into red-colored stars.

The Milky Way falls comfortably between both categories. Although it’s still producing new stars, it’s headed for middle age.

Images of 25 Milky Way analog galaxies found by Newman and team. These objects are shown in order from bluest (top left) to reddest (bottom right) overall color. They are relatively close to the Milky Way - about 500 million light years away. Each one contains hundreds of billions of stars, including many like the Sun. Credit: Sloan Digital Sky Survey

“A few billion years from now, our Galaxy will be a much more boring place, full of middle-aged stars slowly using up their fuel and dying off, but without any new ones to take their place. It will be less interesting for astronomers in other galaxies to look at, too: The Milky Way’s spiral arms will fade into obscurity when there are no more blue stars left,” according to Newman.

In case you have no freshly-driven snow out your front door, our galaxy’s color is roughly halfway between the light from old-style incandescent light bulb and the standard white on a television. The next time you have a chance to see that band of milky light cascading from Gemini’s feet across Orion’s shoulder and into Canis Major, consider its individual stars as snowflakes piling up on your walkway after a winter storm.

Phobos-Grunt cracks up over South Pacific

Approximate reentry point of the Russian Mars probe at 11:45 a.m. CST today.

Time for a collective sigh of relief. The Russian Phobos-Grunt spacecraft crashed down 775 miles west of Wellington Island (just west of Chile) in the South Pacific at 11:45 a.m. CST today according to Russia’s Novosti news service, where you can read the full story. Any surviving fragments are likely chillin’ on the ocean floor.

Perhaps some materials were able to float and may be bobbing around in the waves. Stay tuned to see if anything washes up.

Russian Mars probe demise imminent

This map shows the expected reentry location as predicted by the Russian Federated Space Agency in the South Pacific Ocean off the coast of Chile. The red dots represent amateur satellite watchers. Credit: Screen grab from Simone Corbellini's Visual SAT-flare Tracker 3-D

A satellite observer in Tulsa, Oklahoma saw the Russian Mars probe Phobos-Grunt fly over last night, so it’s still up there. Not for long though. Here are estimates from several agencies and individuals on when the craft is expected to break up and burn as it reenters Earth’s atmosphere today. All times are CST and were updated at 11:26 a.m. January 15. At this point, the U.S. and Canada and much of the rest of the world won’t be under the fall path; it appears the craft could reenter over the South Pacific, South America or southern Europe.

** UPDATE: This just in at 12:45 p.m. Phobos-Grunt crashed down 775 miles west of Wellington Island in the South Pacific at 11:45 a.m. CST today according to Russia’s Novosti news service, where you can read the full story. We can all take a deep breath – any surviving fragments are now sitting on the ocean floor.

* Russian Aerospace Defense Forces – 11:51 a.m.
* The Aerospace Corporation — 11:52 a.m. +/- 20 minutes
* Harold Zimmer (another amateur satellite watcher): 12:02 p.m. +/- 40 minutes
* Russian Federated Space Agency ROSCOSMOS  — 12:08 p.m. +/- 26 minutes
* Ted Molzcan (noted amateur satellite watcher) — 12:11 p.m. +/- 20 minutes
* Ted Molzcan (2nd estimate using a different program) — 1:53 p.m. +/- 40 minutes

Depending on which prediction comes true, the probe could land in a variety of places. Russia has it in the South Pacific, Zimmer places it in the Atlantic off the coast of Brazil, the Aerospace Corporation off the coast of Chile and so on. If you’d like to see all the potential fall spots based on this list and other estimates, please head over to the Visual SAT-flare Tracker 3-D site and click the red-underlined reeentry predictions link. Remember these are predictions. Depending on exactly how it interacts with the atmosphere as it descends, the craft could reenter on the other side of the planet. I’ll have more updates as news arrives.

The moon is in conjunction with Saturn tomorrow morning January 16. The map shows the sky facing south around 6 a.m. local time. Created with Stellarium

I’d be remiss if I didn’t mention that tomorrow morning at dawn the last quarter moon will stop beside bright Spica in Virgo and the planet Saturn. If you haven’t seen Saturn yet this winter, this is an easy way to get there. Use the map at right to help you step over to the trapezoid of stars that form the little constellation of Corvus the Crow.

First-ever picture of a black hole in the works

Comet Lovejoy cruises by the Large Magellanic Cloud, the largest, brightest satellite galaxy of the Milky Way, on January 13. Credit: Rob Kaufman

Lovejoy, the little comet that beat the odds and survived its swing around the sun last month, still shows a sleek cometary form, but it’s barely visible anymore with the naked eye. Amateur astronomers like to joke that they saw an object at the threshold of visibility using a technique called “averted imagination”, a reference to averted vision, which really can help you see a faint object more clearly by not staring straight at it.

Comet Lovejoy’s tail still shows up in long time exposure photos as a long, wispy streak. Depending on the darkness of the sky and lens used, amateurs have recorded tails lengths of between 20 and 37 degrees this week. The comet continues heading northward in the coming days and will finally become visible a week from now for residents in the far southern U.S. in places like Tucson, New Orleans and Key West. On January 22 at 9 p.m. it will be just 5 degrees high due south in the constellation Pictor the Painter’s Easel  from southern Arizona. Hopefully, we’ll still be able to see some of it with binoculars without having to use averted imagination. For a recent NASA update on Lovejoy, click HERE.

A computer simulation of superheated plasma swirling around the black hole at the center of our galaxy. The dark shadow at center is what astronomers hope to finally see. Image by Scott Noble/RIT

Astronomers and physicists from around the world will gather in Tucson, Arizona on January 18 for a conference on the first coordinated endeavor to spy a black hole using the Event Horizon Telescope. Although there’s lots of circumstantial evidence for black holes, no one’s ever seen or photographed one. Despite their enormous masses, most are quite small. The dark shadow of a typical black hole, called the event horizon, measures only about 20 miles in diameter. Larger ones called supermassive black holes contain millions of solar masses and lurk in the centers of many galaxies including the Milky Way. Those can be up to a billion miles across or about the distance of Saturn from the sun. The one in our galaxy contains about 2.6 million times the mass of the sun and is estimated to be no more than 93 million miles across or nearly equal that of Earth’s distance from the sun.

The UA Submillimeter Telescope on Mt. Graham is one of the many radio telescopes forming the Earth-sized Event Horizon Telescope. Credit: Dave Harvey/UA Steward Observatory

Even a 93-million-mile wide shadow is a small thing when seen from Earth’s vantage point 26,000 light years from the galactic center. It’s been likened to spotting a grapefruit on the moon. To see something that small, you need a gigantic telescope. That’s why the new Event Horizon”telescope” will be a combination of 50 existing radio telescopes around the globe to form one monster virtual scope the size of Earth. Utterly cool idea. Data from each instrument will be carefully combined in a central processing center to create the images. Radio was chosen over optical telescopes because radio waves can penetrate the dust and other star gunk between us and the galactic center.

According the University of Arizona press release, participating in the project are the Submillimeter Telescope on Mt. Graham in Arizona, telescopes on Mauna Kea in Hawaii and the Combined Array for Reasearch in Millimeter-wave Astronomy in California. The global array will include several radio telescopes in Europe, a 10-meter dish at the South Pole and potentially a 15-meter antenna atop a 15,000-foot peak in Mexico.

The supermassive black hole in the center of our galaxy is the target of the Event Horizon Telescope. Two views of the Milky Way are shown: face-on from above and edge-on from the side. The solar system is some 26,000 light years from the center.

The Milky Way’s black hole is an ideal candidate because it’s large and relatively close by. Although there are bigger black holes out there, they’re in other galaxies and much too far away. Of course, scientists want to do more than just take a picture. They hope to study the hot, glowing matter swirling around the hole right up until it disappears at the event horizon. Dust and stars that stray near a black hole can end up like water going down your bathtub drain. The material is heated to incandescence through friction as its swirls its way to oblivion. They’d also like to know if the prediction made by Einstein’s Relativity Theory that the event horizon is circular is correct.

It’s an exciting project and I’ll bet you’re as eager as I am to see the first photo of a black hole.

Time’s up for Phobos-Grunt, re-entry expected Sunday

The waning gibbous moon joins Mars tonight in the southeastern sky. This map shows the sky around 11:30 p.m. local time. Created with Stellarium

Late tonight look to the east to see the moon line up below the Red Planet. Binoculars will reveal nice crater detail on the moon but don’t expect them to show much on Mars. Being a small planet only about twice the size of the moon, Mars requires a telescope to see any surface detail. With a magnification of about 70x, you might just see the planet’s tiny white polar cap. 200x will nail it as long as the air is reasonably steady.

While NASA’s Mars Science Laboratory continues on it path toward an August touchdown, the Russian Phobos-Grunt space probe, which has been stuck in Earth-orbit purgatory, will finally come flaming down through the atmosphere sometime this Sunday January 15. The exact time and location of re-entry aren’t known just yet due to uncertainties in its orbit and the upper atmosphere, but it’s expected to land in the Indian Ocean. For now. The satellite could still land anywhere between 51.4 degrees north and 51.4 degrees south latitude. I’ll keep you posted with updates through the weekend. You can also see its current ground tracks (areas it’s passing over) by clicking HERE.

**UPDATE 11:30 a.m. Sunday, Jan. 15: Latest reentry times HERE.

Phobos-Grunt, launched last November 8 by the Russian Space Agency ROSCOSMOS, failed to fire the rockets that would have set it on a course for Mars’ moon Phobos. Its main objective was to land there, drill up a rock sample and return it to Earth for study.

A mockup of the Phobos-Grunt lander. Credit: CNES

One of the concerns out there is the ship’s 8.3 tons of highly toxic hydrazine and nitrogen tetroxide fuel. ROSCOSMOS predicts it all to burn up high in the atmosphere before any pieces of the probe make it to the ground. Some 20-30 pieces with a total weight of about 440 lbs. are expected to survive the fiery descent. Fully-fueled, Phobos-Grunt weighs 29,100 lbs.

Keep an eye to the sky on Sunday and we’ll be in touch. In the meantime, if you have a few extra minutes and would like to learn more about all 41 past missions to Mars, the current Curiosity mission and two more in the works, check out the Planetary Society’s Missions to Mars site.

Last ticket to Neptune! Teeny weeny solar system discovered

Venus floats above an intersection in Duluth recently. Photo: Bob King

You never know when the cosmos is going to drop in. I was driving home the other night and spotted Venus high above a street intersection in eastern Duluth. It was business as usual on Earth as the brightest of the planets cast a few rays in our direction.

Tonight and tomorrow night we’ll be grateful for Venus’ presence, because it gives us a last chance this season to easily find the planet Neptune in binoculars. The two will fit in the same field of view of a typical pair of 7 x 50 or 10 x 40 binoculars for the next two nights.

Go out about an hour and a half after sunset when the sky is dark and point your instrument directly at Venus. The planet is some 60,000 times brighter than Neptune, so don’t stare at it too long otherwise you might lose the night vision you’ll need to see the much fainter Neptune.

Venus and Neptune in a typical pair of binoculars with a 5-degree field of view Jan. 12 and 13th. Venus moves a significant amount in a day's time, Neptune very little because it's much farther away. This view has northeast at top, the way the sky would look facing the planet at nightfall. Created with Stellarium

Using the chart above, navigate upward from Venus to the 7.5 magnitude star and then up from there to another dim “star”. That faint point of light, shining at 8th magnitude, is Neptune, the solar system’s most remote planet currently 2.9 billion miles from Earth. Venus is breathtakingly close in comparison at just 114 million miles. After tomorrow night, Venus and Neptune pretty much part company with love goddess continuing its ascension in the western sky and the god of the sea sinking lower in the west. I love the poetry of the brightest planet in the solar system helping us find the faintest.

This artist's conception compares the KOI-961 planetary system to Jupiter and the largest four of its many moons. The KOI-961 planetary system hosts the three smallest planets known to orbit a star beyond our sun (called KOI-961.01, KOI-961.02 and KOI-961.03). The planet and moon orbits are drawn to the same scale. Credit: Caltech

Stepping outside our own solar system, NASA’s Kepler mission has just discovered the tiniest solar system beyond the sun. Three little rocky planets with diameters of 6,160, 5,765 and 4,500 miles were recently found orbiting the red dwarf star KOI-961.

The latest discovery comes from a team led by astronomers at the California Institute of Technology in Pasadena. The team used data from the Kepler mission, along with follow-up observations from the Palomar Observatory in California and Keck Observatory atop Mauna Kea in Hawaii.

This artist's concept depicts the new solar sytem, so compact it's more like Jupiter and its moons than a star and its planets. Credit: NASA/JPL

Kepler found the new system through patient observation of 150,000 stars in the Northern Cross region of the sky looking for tiny but measurable dips in brightness caused by crossing planets. Even though the new trio of mini-worlds orbit a star cooler than the sun, they’re still too close and too hot to be in the habitable zone. All take less than two days to circle their host star, which is just 1/6th the size of the sun.

What I find exciting about the news is the simple face that red dwarfs have solar systems. As you might guess by their name, dwarfs are smaller and cooler than the sun. They have only between 10-50% of the sun’s  mass and surface temperatures around 6,700 degrees F versus the sun’s 10,000. While red dwarfs are rather faint and inconspicuous, they make up for their diminished status by comprising the vast majority of stars in the universe. They far outnumber the bigger, shinier stars we see in the night sky. The closest red dwarf to Earth is Proxima Centauri in the Alpha Centauri system. Though only 4.24 light years away, you need a small telescope to spot it.

Since red dwarfs are so numerous, the Kepler discovery hints that planets might also be extremely common. Let’s see now. There are at least several hundred billion stars in the Milky Way, so the potential number of planets likely numbers in the billions in our galaxy alone.

The second amazing fact about this meek class of stars is that they live almost forever. Longer than the age of the universe anyway. Being small and relatively cool, red dwarfs burn their hydrogen fuel with great frugality. While the sun in its present form might be around for a total of 10 billion years,  red dwarfs stick around for hundreds of billions of years. Any red dwarfs that formed in the early years after the Big Bang are still with us today. Since a steady energy output over a long period of time is important for life to begin and subsequently evolve into its wonderful and varied forms, planets orbiting red dwarfs would seem the ideal places to begin searching for telltale signs of its existence.

Arc to Mars-turus

Jupiiter pokes out from between "cloud streets" high in the southern sky around 6:30 p.m. on a recent evening. Photo: Bob King

Amazing how quickly the stars and planets slide by. A few months ago you had to stay up late to get a good look at Jupiter. Now it’s front and center (due south) at dinnertime. Everything celestial moves up from the east, peaks at maximum elevation in the southern sky and then eases down into the west. And it’s all because we live on an unstoppable planet traveling 18.5 miles a second around the sun.

You wouldn’t expect the landscape to remain unchanged while looking out the window of a car traveling at 65 mph. Scenes shift by the minute. It’s the same with Earth. As we gaze out into the night sky, starscapes change over days, week and months as we speed ever onward in our orbit. The Summer Triangle’s replaced by the Great Square of Pegasus, which is replaced by Orion, which is replaced by Leo and on and on it goes. The one difference between a fast car and Earth is that the same starry scenes repeat year after year because we travel in a closed loop around the sun, not a straight line.

With night after night of clear skies, January’s Full Wolf Moon got a lot of lookers in the Duluth region earlier this week. Last night through clouds, I could still see enough of the moon to tell it had changed shape. It’s beyond full now and in waning gibbous phase. Looked like an egg to me. And since the angle between the moon, Earth and sun is narrowing, less and less of the moon is illuminated by sunlight with each passing night. We’ll be watching it wane from gibbous to 3rd quarter and finally morning crescent in the next 10 days. The moon also rises later and later as its orbital motion carries it ever eastward.

A grand arc connect the moon-Regulus pair, Mars, Saturn-Spica and Antares in Scorpius tomorrow morning just before dawn. Created with Stellarium

For those of you up around 6 a.m. tomorrow morning (Jan. 12), take a look across the full breadth of the southern sky. The moon will be in conjunction with and directly below Leo’s brightest star Regulus. Now let your gaze slide eastward and you’ll soon bump into fiery orange Mars. Continuing down and left, you’ll soon arrive at the attractive pair of “eyes” formed by Spica and Saturn and finally ruddy Antares low above the southeastern horizon.

Above this grand arc, high in the south, shines the brilliant orange-hued Arcturus. Mars and Arcturus are a near perfect match in color and brightness at the moment. Do their colors look the same to your eye or are they different? Mars is officially at magnitude 0.0 and Arcturus is listed at -0.04, ever so slightly brighter. Can you see this tiny difference? There’s at least one way they should stand apart from one another. I’ll give you a hint: it has to do with our atmosphere. Go out for a look and let us know what you see.