Tuesday, October 28, 2008

Eldritch eyes in the sky watch over Halloween revelers

Eldritch eyes in the sky watch over Halloween revelers
by Dave Adalian


Tomorrow night, when ghosts and goblins, witches and all sort of evil thing take to the streets for Hallowe’en, an eerie trio of eldritch eyes from the early evening southwestern sky will watch them as they go.

Just after the sun sets at six o’clock, a new moon a scant few hours old will become visible a handful of degrees atop the horizon. With only the barest slice of its leading limb lit by dying sunlight the moon might look not entirely unlike the giant bloodshot eye of some cosmic creature leering down as costumed children dart among the neighborhood houses, collecting their treats and playing their tricks.

This ominous orb may be so thin it hides among wisps of lingering autumn mist, so seek for it instead by finding Venus, shining just above the moon like a baleful, unblinking witness, then wait until the sky grows darker and the moon more distinct.

Sometime also in that first hour after dark the tiny red light of Antares will appear, a bloody jewel beneath the moon. So, too, will the brighter stars of a setting Sagittarius come out, cold and shimmering beside the moon, and there above them will be Jupiter glaring out into the night.

Those three sky-bound watchers will not contain their vigil to a single eve, and the moon will float between the other two like an unquiet spirit, moving past Venus then up beyond Jupiter as the first few long November nights unfold.

These three probing autumn eyes and their glittering companions are not the only specters lingering in the heavens on Hallowe’en night. High overhead, three bright stars form a mystic triangle: white Vega in Lyra the farthest west of the group, Altair in Aquila at the south-most vertices and Deneb in Cygnus cutting the eastern angle.

In the north the Big Dipper lies low against the horizon with its bowl open, perhaps to gather candy or to be filled with water from Aquarius on the other side of the sky for cosmic apple bobbing. As always, the Dipper’s two end stars point the way to Polaris, and there beside the North Star is the W shape of Queen Cassiopeia, a ghoulish woman who would have fed her own daughter to the sea serpent Cetus.

Then in the east above the mountains the wraithlike Seven Sisters of the Pleiades begin their nightlong journey toward the west, and midnight finds them at the zenith when Halloween turns to All Saints’ Day.

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This column originally appeared in the Visalia (Calif.) Times-Delta and the Tulare (Calif.) Advance-Register.

Tuesday, September 23, 2008

Starry signs point toward fall

Starry signs point toward fall
by Dave Adalian


‘You know Orion always comes up sideways.
Throwing a leg up over our fence of mountains
And rising on his hands he looks in on me. ...’
-- Robert Frost, The Star Splitter

It’s that time again, when we pack away summer in our memory and all too soon turn our thoughts to woolen hats, warm coats and icy fog.

Some of us declare the season at an end when Labor Day rolls around and we spend three lazy days enjoying the last few hours of summer heat with barbecues, long stretches of green grass and cool dips. Others of a more serious and scientific mind say the season passes on the equinox, as the Sun, our giver of life and warmth, turns south again to shine on more exotic lands.

I suppose they’re right, but for me the change of season is measured by the stars.

First sure sign summer’s at an end comes just after dark when the Summer Triangle of Vega, Deneb and Altair sits directly overhead insisting that the season isn’t quite over yet, not yet! But we know better, and each next long night finds them farther west than the one before.

If that weren’t evidence enough, when we turn to the east we find four bright stars in an enormous square -- the Great Square of Pegasus -- looming, and there beside it to the northeast the glowing ghost of the Andromeda Galaxy, a haunting specter of a Hallowe’en soon to be.

In the hour before midnight, when the Square takes the place of the Triangle at the top of the sky, the raging bull of Taurus begins its autumn charge over the eastern mountains: Aldebaran a glowing red eye in the V-shaped face of the Hyades and the seven starry sisters of the Pleiades riding on its back.

Were there any doubt left in us by the hour after midnight, the giant figure of Orion climbing sideways into the sky would chase it from our minds. The ancestor of us all, this ancient man of the mountain has come again to rule over the long, cold nights of a winter not yet quite begun.

In that coldest hour just before dawn, Orion the Hunter, followed by the faithful Dog Star Sirius, takes his stand in the south where he looks over the harvest and waits for the frozen chase to begin. Autumn has arrived.

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This column originally appeared in the Visalia Times-Delta and Tulare Advance-Register in August 2008.

Wednesday, August 27, 2008

Triple conjunction challenges eagle-eyed planet hunters

Triple conjunction challenges eagle-eyed planet hunters
by Dave Adalian


The next two weeks present a challenge for planet hunters in possession of either keen eyes or a pair of binoculars. Those who take up the difficult task will also need an unobstructed view of the western horizon and patience.

About half an hour after sunset tonight, Venus should be obvious to the naked eye directly west and around 10 degrees or about two hand-widths above the horizon in sunset’s afterglow.

The most eagle-eyed might also see dimmer Mercury shining in the gloaming less than a hand-width to the left of Venus. Those of us without such keen vision will have to resort to binoculars. Just about any will do, though a magnification of at least seven times is recommended.

But, even those with the sharpest of eyesight likely won’t find dim Mars just two hand-widths above and to the left of the Goddess of Love. For that, binoculars are a must, but the extra effort will be worthwhile as this trio draws into an ever tighter triangle during the first half of September.

While the God of War is still about 10 degrees separate from the Goddess of Love, by next Wednesday the distance will be half that. Four days later on Sept. 7, Venus and Mars will be only 2.5 degrees apart. The gap will be only 1.75 degrees the next night, and a mere 1.5 the night after that.

On Sunday, Sept. 10, the two planets will appear less than a single degree apart, and on Sept. 11, when the two are at their closest, only three-tenths degree separates them.

During the close call on Sept. 11, when Love and War appear almost on top of one another, remember they’re really millions of miles apart. Though they look close enough to collide, Venus is 138 million miles away from Earth, while Mars is 227 million miles distant.

Mercury, meanwhile, is a relatively close 88 million miles away from Earth.

While this triple conjunction unfolds, the trio will be setting earlier night to night, so by the end even the keenest of eyes will need binoculars to follow the show. Just don’t point them at the sky until after sunset to avoid eye damage.

For a beautiful bonus look for the new moon near the trio on Sept. 1, when it will hover just above the horizon but below the planets, and again on Sept. 2, this time off to their left.

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This column originally appeared in the Visalia Times-Delta and Tulare Advance-Register in August 2008.

Tuesday, August 19, 2008

Earth’s Seven Sisters are out this Week

Earth’s Seven Sisters are out this Week
by Dave Adalian



All seven of Sol’s other planets are out this week, and with a little luck and patience earthbound planet hunters will be able to collect them all.

Tonight (Aug. 21, 2008) is the night to be lucky -- and careful -- to find the first target. Saturn follows the sun over the western horizon about 30 minutes after sunset, making it a difficult target for the naked eye.

Because it’s bright, Saturn should turn up in the reddened western sky glow. For safety sake, start searching for the ringed planet only after Sol’s disk has completely disappeared. This is especially true when using binoculars: Viewing the sun through optics will cause vision loss.

If Saturn won’t cooperate tonight, Friday and Saturday are also possibilities, but chances of seeing the sixth planet grow slimmer each night.

After the search for Saturn, finding Venus and Mercury will be a breeze. (Well, easier anyway, but because they’re so low the search might still require the aid of binoculars.)

The innermost planets are in close conjunction for the next few days, and can be seen together above and to the left of where the sun met the horizon at sunset. The pair may also help locate elusive Saturn: it will be between the pairing of the first and second planets and the sun.

Follow that imaginary line connecting Sol, Saturn, Mercury and Venus -- the ecliptic -- further up and to the left to find ruddy Mars. The Red Planet is now so far away it’s little more than a reddish pinpoint, but like all the planets it doesn’t twinkle. Again, binoculars will help.

King Jupiter is impossible to miss, shining bright in the south on the shoulder of Sagittarius the Archer after sundown. The only reason for binoculars here is to search for the planet’s larger moons.

Binoculars will be a must to find Neptune, the eighth planet out. Look for Neptune’s tiny blue-green disk about halfway up the sky due south at 30 minutes after midnight tonight. After Pluto’s demotion, Neptune is now the farthest planet out.

Closer in but farther out along the ecliptic at present is the seventh and final planet, Uranus. It will be due south about 2 a.m., and can be seen with the naked eye. Because Uranus is at the edge of the eye’s range, binoculars will help you locate it. A finder chart will make finding both Uranus and Neptune much easier.

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This column was originally intended for publication in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register in August 2008. For some reason that didn't happen. I don't know why. So, I wrote them another one, which is the next post after this.

Tuesday, July 01, 2008

War, Change and the Little King

Planets and Stars Gather:
War, Change and the Little King
by Dave Adalian


Look to the west tonight between sunset and 10 o’clock and you’ll find a pair of planets and a bright star artfully grouped just above the reddened horizon.

All year long, the ringed planet glided slowly through Leo the Lion while angry red Mars sat nearby in Cancer the Crab. As summer reaches its height, the War God is on the move, slipping into the lion’s den to join Saturn, Roman god of change and growth.

As the trio stands now you’ll find ruddy Mars between the brightest star in Leo, brilliant white Regulus, on Mars’ right and yellowish Saturn to its left. Although low to the horizon, the Bringer of Change still outshines almost everything else in the sky.

Of the three, Mars is smallest and closest, only 4,000 miles wide at its widest, compared to Saturn’s nearly 75,000-mile girth (or 150,000 miles if you count the rings, which are the largest structure in the Solar System after Sol).

But, Mars, Saturn and even Sol are dwarfed by Regulus, which carries a bulk three and a half times the sun’s. It’s about that many times as wide in the middle, too. Regulus -- the star’s name means “little king” -- also spins faster than the sun. Sol turns once each month; Regulus turns once every 16 hours, almost fast enough to fling the star apart, but not quite. It is fast enough to make Regulus oblate, meaning it’s squashed flat like a cosmic M&M candy.

Tonight, Mars will be closer to Regulus than Saturn, but the two planets are headed for a very close encounter on July 9-10, with Mars seeming to move steadily in Saturn’s direction during the next seven days. All during the week, the trio will make for spectacular viewing, and the show gets even better on the nights of July 5 and 6 when the conjoined planets and Regulus are met by a young crescent moon, which will be below the trio the first night and beside it the second.

This event effectively marks the end of the Saturn viewing season, and Mars and Saturn won’t be this close again until 2022, but planet hunters take heart: While Saturn and Mars are leaving the sky, Jupiter, Saturn’s son and king of the planets, is coming into its best, appearing as the brightest thing in the sky. Find it by looking southwest after sundown.

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This column originally appeared in the Visalia (Calif.) Times-Delta and the Tulare (Calif.) Advance-Register in July of 2008.

Sunday, June 01, 2008

Stupid Questions

Stupid questions: the dark of night reveals more than empty space
by Dave Adalian



Why is the night dark?

It sounds like one of those questions you have to be stupid to ask, but the answer can lead to a deeper understanding of how our universe works.

To be fair there is more than one answer because there’s more than one reason the sky at night is dark. The obvious reason is that at night we’re on the far side of the planet from Sol in the shadow of the Earth, so it’s dark. Simple.

But, why isn’t the night sky lit with all the shine from the uncountable number of stars aglow in the heavens? It’s the answer to this second question that’s revealing to the inquisitive mind.

If we lived in a finite universe with an even distribution of stars endless daylight is exactly what we’d see. Because the energy would have nowhere to escape, the stars would warm their surroundings until the entire universe glowed evenly with their heat.

But, that isn’t what we see.

It wasn’t until 1829 that it occurred to astronomer Charles Olbers to ask why the night is dark, and he was promptly ignored. No one had an answer for him then.

One hundred years later, another astronomer, Edwin Hubble, noticed the farther away from us an object is the more its light is distorted when it arrives here. The distortion is caused by speed, and the farther away something is the faster it appears to be traveling. The universe, Hubble had discovered, is expanding at an ever greater rate.

So what?

So imagine a party with 200 people in your living room and more on the way. There would be activity everywhere you looked, someone doing something, laughing, drinking, dancing, talking. You’d be overwhelmed like dim starlight on a bright day.

Imagine that same party in an airplane hanger and the place would seem practically deserted, dark and empty.

Now, what if your living room got bigger every time a new guest arrived? No matter how large and raucous the party became your living room would never seem crowded and the guests would never overfill it.

Strange as it seems, that’s how the universe appears to operate. The older the universe gets the larger it grows, and if we had stopped to think about why the sky at night isn’t filled with starlight, we’d have figured this out years before Hubble actually did it.

And, that is why it’s important to ask stupid questions.

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This column originally appeared in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register.

Thursday, May 08, 2008

Watch Mercury rise and fall all through May

Watch Mercury rise and fall all through May
by Dave Adalian


If you go outside about half an hour after sunset tonight and look just above the western horizon where the sunburned sky has yet to fade you’ll find bright pink Mercury, fastest of the planets, shining in the Sun’s wake.

Elusive Mercury--the smallest of the planets at 3,032 miles wide--is putting in its best appearance of 2008 during May. But, you’ll still need to be quick to see it.

Just 800 miles wider than Earth’s moon and never further than about 36 million miles from the Sun, Mercury is difficult to find until the sun is far enough down. By then, though, the time for viewing is short.

When you find it, you’ll notice the messenger of the gods carries a distinctly reddish hue, but it’s an illusion. Mercury, which is similar in size to our moon, is also about the same color, and Mercury, too, is covered in thousands of impact craters that bear witness to our Solar System’s violent past.

Mercury’s ruddy tint, however, is an artifact of the air, which distorts the planet’s color as the light from so far away travels through Earth’s dust-filled atmosphere.

If you look at Mercury through a telescope, you’ll notice it also shares another trait with the Moon: it goes through phases. Right now, the Iron Planet--so called because it has a massive iron core larger even than Earth’s--is about 60 percent lit. But, it’s waning, and by the middle of the month it will be just 25 percent illuminated.

At the same time, however, Mercury is also coming closer to Earth, and so while its dark side comes into view it will also seem to grow larger.

As you watch night to night, notice that Mercury trails a bit further behind Sol for the first few days. Around midmonth, Mercury will stop drifting away from the sun, then after a couple of days will start falling back sunward. A week later it will take the keenest of eyes to detect Mercury in the afterglow of twilight, and by the end of the month there’s no chance of seeing it at all.

While Mercury is invisible to us back on Earth, it will be rounding the sun on an inside track then emerging on the morning side. But, it won’t be visible to early risers until late June. It will be easy to find about half an hour before dawn on July 1 when it’s paired with the thinnest sliver of an almost new moon.

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This column originally appeared in the Visalia Times-Delta and Tulare Advance-Register on May 8, 2008.

Wednesday, January 23, 2008

A Week of Wintertime Planet Watching

A Week of Wintertime Planet Watching
by Dave Adalian

In the last hour before the Sun comes up tomorrow, the constellation Sagittarius will just be rising above the horizon in the southeast. There among the stars of the Archer, which are usually seen on much warmer summer evenings, will be a pair of bright planets racing toward conjunction on the first day of February.

A conjunction, of course, is a coming together, and this meeting of wanderers will be an especially close one. On Friday morning at about 6 a.m. Venus will be almost directly southeast and easy to find as the brightest thing in the sky besides the nearly full moon. Down, to the left about seven degrees away and not nearly as bright as Venus, early risers will spot Jupiter.

For the next week the two heavenly bodies will drift closer to each other, moving together about a degree each day as Venus’s orbit brings it seemingly closer to the sunrise and Jupiter. By Monday morning, the gap between the two will have closed to just four degrees, and those who haven’t been making daily checks will notice a huge difference since their last look.

As the week continues the goddess of love and her sire will make their way toward a father and daughter reunion in the early twilight of Friday, Feb. 1 when the pair will be separated just six-tenths of a degree. This is only slightly larger than the width of a full moon.

The Moon that morning will be a very thin crescent at the end of its cycle, riding nearby in the stars of Scorpius. It will not be alone. Close by to its left will be Antares, the red heart of the scorpion.

Those who like to sleep in won’t be left out of the planet viewing, and they don’t have wait for next week to get started either. Tonight by about 9 o’clock, Mars will be almost directly overhead, still glowing brightly after making a close approach in late December.

Surrounding the Red Planet are the six bright stars of the Winter Circle. Going clockwise: dazzling Sirius, white Procyon, Pollux with its dimmer twin Castor, lonely Capella, red Aldebaran and brilliant Rigel.

Below them all in the east nestled in the stars of Leo the Lion sits the Moon, just two days past full. Perched there above it, glowing a golden yellow, is ringed Saturn finally making its return to nighttime skies.

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This column originally appeared in the Visalia Times-Delta and Tulare Advance-Register on Jan 24, 2008.

Thursday, December 20, 2007

Planetarium Show January 11!

"The Hero, the Lady and the Stars of Winter" will be shown at the Sam B. Pena Planetarium, 2500 W. Burrel Ave., Friday, Jan. 11, at 7:30 p.m., with stargazing with members of the Tulare Astronomical Association to follow.

Tickets are $4 for adults and $3 for children, and are available at the planetarium's office or by calling 737-6334.

Click here for the Tulare County Office of Education's Impact Center, home of the Pena Planetarium.

Click here for a map of the planetarium and observing site.

Tuesday, December 18, 2007

The Week Before Christmas: A Holiday Visit from Mars

The Week Before Christmas: A Holiday Visit from Mars
by Dave Adalian


‘Twas the week before Christmas,
When up in the sky,
There appeared a bright star
Out of place to my eye.
It was in the wrong space,
With the wrong color, too,
And it didn’t twinkle,
Which is something stars do.

It had a hue like a campfire
And was awfully bright;
It outshone all the other stars
With the strength of its light.
“Could that be Rudolf?”
I wondered out loud.
“Do you think?” came an answer;
I was drawing a crowd!

It was then I remembered
That I’d seen this before:
It was fourth planet Mars
Come to knock on our door--
It’s every two years,
Regular as a clock,
Mars crosses the heavens
To visit Third Rock.

“That’s not Santa,” I said,
Pointing up at the sky.
“It’s the Red Planet,
And I’ll tell you why!
All warm autumn long
We’ve watched it grow nearer,
And now cold winter skies,
Make it seem even clearer.

“That planet a-shining
Way up high near’ to Heaven
Is now at its closest
For two-thousand-and-seven.
So bundle up Christmas Eve,
And step out after dark.
You’ll see quite the sight,
One to make you remark!

“It’ll shine in the east,
Bright fiery Mars hanging low,
And right along side it
The Full Moon will glow--
All night long the War God
Along with Luna will fly
Accompanying St. Nicholas
Away up there in the sky!

“As you stand struck with awe
At that celestial wonder
If your thoughts back to Earth
For a moment do wander
I’ll seize on the instant
For there’s something to say:
I most sincerely do wish you
A wonderful winter holiday!


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This column originally appeared in the Visalia Times-Delta and Tulare Advance-Register on Dec. 20, 2007.

Saturday, December 01, 2007

Meeting Wednesday, Planetarium Show & Star Party Friday

Planetarium Show & Star Party Friday

"The Lady, the Hero and the Stars of Winter" premieres this Friday, Dec. 7, at the Pena Planetarium, 2500 W. Burrel Ave. in Visalia, at 7:30 p.m., with stargazing with members of the Tulare Astronomical Association to follow. The show will run again Friday, Jan. 11, also at 7:30 p.m.

Tickets are $4 for adults and $3 for children, and are available at the planetarium's office or by calling 737-6334. Click the link on the upper right side of this page for more information.

TAA Business Meeting Wednesday Night

The Tulare Astronomical Association will hold its monthly business meeting at 6 p.m. on Wednesday, Dec. 5, at the offices of the Delta Vector Control District, 1767 W. Houston Ave. in Visalia. This is a non-viewing meeting.

Thursday, November 08, 2007

A Long Look into the Distant Past

A Long Look into the Distant Past
by Dave Adalian


How far can the human eye see?

The question sounds like something a Zen master might ask a student to bring him enlightenment, but unlike puzzling over the sound of a single hand clapping, this question actually has an answer.

Two and a half million light years, about 14.7 billion billion miles, is as far as the human eye can look.

That’s how far the empty void between our galaxy, the Milky Way, and our nearest large neighbor, the Great Andromeda Galaxy, stretches, and the Great Andromeda Galaxy is the farthest thing the human eye can see without the help of a telescope.

That distance is also as far back in time as we can look.

To find the Great Andromeda Galaxy find a dark sky away from city lights on a moonless night during late fall or early winter and look almost overhead for the Great Square of Pegasus, a huge square formed by four bright stars. Then look northeast for an M-shaped group of stars in the constellation Cassiopeia and imagine a line between the brightest of these stars and the brightest star in the Great Square. Just east of that line about two-thirds of the way along it in the direction of Pegasus you’ll see the bright glow that is the light of the Great Andromeda Galaxy.

That faint and distant glow left its home galaxy 2.5 million years ago, long before modern human beings walked the Earth. When we look at Andromeda, we are looking back in time and seeing that galaxy not as it is today but as it was in the long ago past.

We’re also seeing almost exactly what a person living on a planet in the Andromeda Galaxy sees he when looks up on a clear and moonless night and gazes back across the empty void and the endless years at the Milky Way, since the two galaxies are very similar in size and form with each containing billions of stars arrayed in vast and sweeping spirals.

If the sky is dark enough and one’s eyes are good enough, the Great Andromeda Galaxy appears huge, stretching about five degrees across the sky or 10 times the width of a full moon.


What isn’t obvious when looking at Andromeda is that it and the Milky Way appear to be on a collision course, moving toward each other at more than 250,000 mph. Not to worry, however. Even at that speed if the two do collide it won’t be for another three billion years.

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The Tulare Astronomical Association and the Tulare County Office of Education will present The Hero, the Lady and the Stars of Early Winter, a planetarium program written and narrated by Starry Nights columnist Dave Adalian Dec. 7 and Jan. 11 with a free star party to follow. For details, check the Starry Nights blog at starry-starry-nights.blogspot.com or the Pena Planetarium website at www.tcoe.k12.ca.us/ImpactCenter/Planetarium.shtm

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This column originally appeared in the Visalia Times-Delta and Tulare Advance-Register on Nov. 22, 2007.

Tuesday, November 06, 2007

TAA to Meet Nov. 7

The Tulare Astronomical Association will hold its monthly business meeting at 6 p.m. on Wednesday, Nov. 7, at Amigos Restaurant, 5113 W. Walnut Ave. in Visalia. This is a non-viewing meeting.

We'll have news from the Sequoia Riverlands Trust regarding the Dry Creek Drive site.

Saturday, October 13, 2007

UC Berkeley Astronomy Lectures Online

As a public service, University of California, Berkeley is allowing everyone streaming access to webcasts and podcasts of the lectures of several of its classes, including two classes entitled Introduction to General Astronomy, via Real Player. The course lectures are also downloadable.

To view them, go to http://webcast.berkeley.edu/ and select the "/courses" link. The two astronomy courses are listed as Astro 10P and Astro C10/LS C70U.

Monday, October 01, 2007

Early Autumn is the Season of the Moon

Early Autumn is the Season of the Moon
by Dave Adalian


In ye olde days, when folks made their livings off the land, the Moon was an invaluable tool for bringing in the harvest when days turned short just as the crop came ripe.

Light the face of the full moon reflects, even though it’s much dimmer than the Sun’s, is enough to swing a scythe by. It allowed farmers to work well past sunset and get food they and their animals needed to survive a long, harsh winter into storage before wet and freezing weather rotted it in the fields.

While most of us toil in air-conditioned surroundings these days, echoes of earlier times are still with us in the names we give each month’s full moon and in the myths that surround our satellite.

The full moon of September, when the last of the corn is being cut and the hay mowed, is the Harvest Moon, the one that helped our ancestors see their way through the night, and it still carries that honorific today. October’s full moon, rising when the fields are cut to stubble and prey has nowhere left to hide, is still called the Hunter’s Moon in these modern days of supermarkets.

The other thing autumn’s moons carry with them is the myth they loom larger in the sky than moons do the rest of the year. It isn’t so.

The Moon is always the same size, and though its orbit isn’t a perfect circle -- meaning it’s sometimes slightly closer to Earth than at other times -- the difference isn’t noticeable to the naked eye. But, when the Moon is close to the horizon, it appears bigger than when it’s high overhead. A trick of the eye that’s perhaps more noticeable this time of year when more people are out and about at moonrise.

On Friday, the Moon will be at first quarter, meaning its western half will be illuminated, and it will be due south at sunset. Watch as it grows fatter and moves east from night to night until it reaches fullness seven days later.

That night, when the full moon rises over the Sierra, notice how large it looks, then measure it by holding your hand at arm’s length with a pinkie extended. Half the tip of your little finger should cover it.

Come back outside closer to midnight, when Luna is riding high, and measure her again. She’ll look much smaller up among the stars, but your finger will tell you the difference is all in your head.

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For more on the names of full moons, check out this article from the Old Farmer's Almanac.

What phase is the Moon in tonight? Click here to find out.

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This column appeared originally in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register on Oct. 18, 2007.

Planetarium Show this Friday!

The show I've written for the Sam B. Pena Planetarium, 2500 W. Burrel Ave., premieres this Friday, Oct. 5, at 7:30 p.m., with stargazing with members of the Tulare Astronomical Association to follow. The show will run again Friday, Nov. 2, also at 7:30 p.m.

Tickets are $4 for adults and $3 for children, and are available at the planetarium's office or by calling 737-6334.

Click here for the Tulare County Office of Education's Impact Center, home of the Pena Planetarium.

Click here for a map of the planetarium and observing site.

Friday, September 28, 2007

Do Some Simple Science!

Here's a chance to do some real science while stargazing. The Great Worldwide Star Count is a project aimed at finding out how much light pollution has dimmed our view of the stars around the planet. This simple collaborate effort of "citizen scientists" requires just a bit of effort and will help us get a better picture of our night skies around the planet.

Click here for The Great Worldwide Star Count.

Friday, September 14, 2007

Mars Really Is Looming Large

Mars Really Is Looming Large
by Dave Adalian




Used to be Mars was a hot topic of astronomical conversation only once every two years.

That’s how long it takes Earth to swing around the Sun and catch up with the fourth planet of our solar system, which itself is racing along in the same direction.

These days, thanks to the Internet, Mars reappears every August, and it’s always going to be the size of a full moon when it arrives. At least that’s what emails my readers forward to me say. The questions they usually send along with these emails run like this:

“I know this can’t possibly be true, but I wanted to know for sure so I don’t miss it if it is, so is it?”

No.

Welcome to the annual Mars hoax, an unsinkable chain letter saying Mars will appear the same size as the full moon in August. The people who email know this can’t be right, but the allure of Mars is such they want it to be. So do I. But, alas, it isn’t going to happen. Never.

But the god of war will be here soon, and this year, Santa won’t be the only thing dressed in red, white and black showing up on Christmas Eve.

Mars reaches opposition on Dec. 24. It will rise as the Sun sets and stay up all night. It does this because the red planet is opposite the sky from Sol, which is what “opposition” means.

It also means the time to start watching Mars is now.

The reason my hopeful correspondents know Mars isn’t going to be the size of the full moon is we’d start seeing it looming ridiculously large months before the big show. The same is true for this lesser but at least real apparition: Mars is already showing itself, rising around 11 p.m. between Orion and Gemini and getting high enough for good viewing by 1 a.m.

And, Mars isn’t sitting still. Right now Earth and the red planet are zooming toward each other at around 25,000 mph. In October 2006, Mars was on the other side of the Sun from Earth, 243 million miles away. Now, a year later, Mars is just over 90 million miles distant, and the gap is shrinking fast.

Between now and Christmas Eve, Mars will come 35 million miles closer to Earth and brighten by a factor of four, all the while rising earlier and earlier each night. Just step outside and you can watch it happen.

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The Tulare Astronomical Association and the Tulare County Office of Education will present The Stars of Autumn, a planetarium program written and narrated by Starry Nights columnist Dave Adalian on Oct. 5 and Nov. 2 with a free star party to follow. For details, check the Starry Nights blog at starry-starry-nights.blogspot.com or the Pena Planetarium website at www.tcoe.k12.ca.us/ImpactCenter/Planetarium.shtm.

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This column appeared originally in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register on Sept. 20, 2007.

Thursday, September 13, 2007

Moon 2.0

Google and the X Prize Foundation are sponsoring two $30 million purses to the first two teams to put a roving robot on the Moon. There are bonuses for discovering water ice in the permanently dark craters near the lunar south pole, surviving the long lunar night and visiting the remains of past lunar exploration. Blast off!

THE GOOGLE LUNAR X PRIZE HOMEPAGE

Monday, September 10, 2007

TAA at the Pena Planetarium

I've written a script for a planetarium show at the Tulare County Office of Education's Pena Planetarium, which will be shown the nights of Oct. 5 and Nov. 2. The show will cover some of the constellations of autumn, specifically those in and around the Summer Triangle and Hercules. Keep an eye on this space or check the planetarium's website for details.

We'll be setting up our telescopes for a look at some of the objects mentioned in the program after the show is over.

The Pena Planetarium at the TCOE Impact Center

Wednesday, September 05, 2007

TAA to Meet Sept. 6

The Tulare Astronomical Association will hold its monthly business meeting at 6 p.m. on Thursday, Sept. 6, at Amigos Restaurant, 5113 W. Walnut Ave. in Visalia. This is a non-viewing meeting.

Map to meeting location.

Monday, August 06, 2007

Sky Dragon Swallows the Moon

Sky Dragon Swallows the Moon
by Dave Adalian


In the early morning hours of Tuesday, Aug. 28, the Moon will be swallowed by a great sky dragon that will slowly consume it, turning the lunar disk a deep blood red.

The Moon will not sit well on the dragon’s stomach, and 90 minutes later it will escape back into the sky to the thunderous noise of exploding firecrackers, the clash of pots and pans and the hoarse and angry screaming of humans shouting to frighten the hungry dragon away.

At least that’s the way it would happen if this were ancient China. If we were among the Vikings, it would be pretty much the same thing, with a wolf eating the Moon instead of a dragon. For the Serrano Indians, it’s the spirits of the dead doing a bit of celestial binging and purging.

The reality isn’t nearly so fanciful, but it’s at least as dramatic.

Usually once or twice a year--but sometimes thrice or even not at all--the Earth, Moon and Sun will for a brief few minutes line up so Earth’s shadow falls across the Moon, nearly blotting it from the sky. But, because Earth’s atmosphere bends some of the sunlight, the shadow is never completely dark, giving the Moon a red or brown tint during totality.

On the morning of Aug. 28, the Moon will begin to darken at a few minutes before 1 a.m., as it enters Earth’s penumbra, the lighter ring of shadow surrounding Earth’s darker inner shadow, the umbra.

Just moments after the Moon is entirely within the penumbra, a minute or two after 2 o’clock, its leading edge will enter the darker umbra and begin to take on the ruddy aspect of blood.

For almost an hour the Moon will fall deeper into the umbra until by 3 a.m. it will be entirely consumed by darkness.

The only way out for the Moon is through, a journey that will take some 90 minutes to complete. The Moon will reemerge beginning about 4:25 a.m., exiting the umbra entirely an hour later.

The Moon will still be in the lighter penumbral shadow for another hour, finally escaping Earth’s shadow into the pale blue light before dawn, only a scant few minutes before the Sun rises on the opposite side of the sky and the Moon sinks into the west.

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This column appeared originally in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register on Aug. 23, 2007.

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For a more technical discussion of the Aug. 28, 2007 lunar eclipse, along with charts and times, visit NASA's Eclipse Home Page.

Saturday, July 28, 2007

TAA to Meet Aug. 2

The Tulare Astronomical Association will hold its monthly business meeting at 6 p.m. on Thursday, Aug. 2, at Amigos Restaurant, 5113 W. Walnut Ave. in Visalia. This is a non-viewing meeting.

Saturday, July 14, 2007

Falling Stars on Hot August Nights

Falling Stars on Hot August Nights
by Dave Adalian

About every 130 years or so, Comet Swift-Tuttle swings by Earth, circles the Sun, then heads back out into the dark, cold recesses of the Solar System.

As it sails along, the comet loses bits of itself, leaving a trail of tiny specks of ice and rock in its wake. As the years go by these comet crumbs spread out along Swift-Tuttle’s orbit into a huge doughnut-shaped cloud. Then, each August, Earth dives into that cloud, and the result is the annual Perseids meteor shower.

The Perseids are the year’s most reliable shower, with only a dud or two in the last decade. The 2007 show isn’t expected to bring the 400 or more meteors an hour seen in the early 1990s but away from city lights under a transparent sky, 80 to 100 an hour during the peak isn’t an unreasonable expectation.

The 2007 Perseids reaches an apex the night of August 12-13, with the greatest number of meteors predicted to fall between 10 o’clock and a half an hour after midnight.

The new moon will be absent from the sky, which is perfect for a meteor watch. Unfortunately, the peak’s timing is a bit off.

Best time to see meteors is around 2 a.m., when the sky overhead is facing forward with respect to Earth’s motion around the Sun, making it just like a car’s windshield. There are always more bug-splats on the front window than on the sides, and during the peak, the sky here will be like the side window of a car. So, like bug-splats on a side window, there will be fewer meteors but the ones we do see will be more like spectacular streaks than splats.

These meteors, known as earthgrazers, will come blazing in from the northeast, where the constellation Perseus--which gives the shower its name--will be rising, then shoot across the sky toward the opposite horizon.

Fortunately, the Perseids are very active around the peak. Rates of 40 meteors an hour the nights before and after are a real possibility. The Perseids is also a long shower that began July 17 and lasts through Aug. 24.

But, the best night for Perseids watching will be the night of the peak, and meteors will still be falling when 2 a.m. rolls around. And for those who stay up late, there’s the bonus of seeing Mars rise among the meteors around 1 a.m.

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This column appeared originally in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register on July 26, 2007.

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For the International Meteor Organization's 2007 Meteor Shower Calendar, which includes technical discussion of the showers and sky charts, click here.

Tuesday, July 03, 2007

TAA Monthly Meeting July 5

The Tulare Astronomical Association will hold its monthly meeting on Thursday, July 5 at 6 p.m. at 4423 E. Sycamore Ct. in Visalia. All interested parties are invited to attend.

Directions:

FROM HWY 99: GO EAST ON HWY 198.

EXIT ON LOVERS LANE – TURN LEFT.

TURN RIGHT ON HOUSTON AVE.

RIGHT AFTER YOU PASS SOL ROAD, LOOK FOR TALL TREES ON RIGHT THAT IS COMSTOCK (EASTOAK ESTATES SUBDIVSION) TURN RIGHT IMMEDIATELY.

GO TO NEXT TO LAST STREET, TURN LEFT ON SYCAMORE COURT.

WE ARE ON THE RIGHT SIDE OF SYCAMORE.

Monday, June 25, 2007

Summer of the Planets Continues

Summer of the Planets Continues
by Dave Adalian


The brightest of the planets will meet the most beautiful of the planets in the west this weekend.

Since the start of the year, dazzling Venus has been hanging in the western sky after sunset. Long night after long night, the evening star grew brighter and higher in the sky until it reached its peak in the much shorter nighttimes earlier this month.

Now, the goddess of love has begun her decent back into the overbearing glare of the sun, but before she fades away she’ll be visited by another of the planets, the one considered by many as the Solar System’s loveliest.

Six months ago, when Venus was making her first tentative appearance as daylight faded in the west, Saturn was becoming prominent in the east. As the months passed, nightfall found Saturn further west each night until it was hanging low in the western sky at sunset.

While Saturn was creeping across the celestial sphere, Venus waited patiently. The two will finally meet this weekend.

When the sun goes down tonight, Venus will be where it has been all year, following the sun as it sets in the west. About an hour after sundown, Venus will be unmistakable as the brightest thing in the western sky. Above and to its left you’ll find a much dimmer Saturn.

Though Saturn, at 75,000 miles in diameter, is much larger than 8,000-mile-wide Venus, Venus is much closer to Earth, a mere 50 million miles away compared to a whopping 925 million miles for the more distant ringed planet.

Tonight, the two planets will be less than 2 degrees apart, about twice the width of the tip of your little finger held at arm’s length or about four times the width of a full moon.

By Friday night, the pair will have closed to just 1 degree, close enough you will be able to hide both of these worlds behind your little finger. Fittingly, on Saturday, Saturn’s day, the two will be at their closest, about three-quarters of a degree apart.

The two remain less than a degree apart as Saturn slips by on Sunday, then they’ll be just more than a degree apart when Monday comes to a close.

Keep watching the pair as the grow apart and on July 16 you’ll be rewarded with the spectacular grouping of Venus, Saturn, the moon and the bright star Regulus.

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This column appeared originally in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register on June 28, 2007.

Tuesday, June 12, 2007

TAA July Meeting

At the TAA business meeting in June, it was decided to hold monthly meetings to conduct club business and discuss the latest developments in astronomy. The July meeting, open to all interested persons, will be held at 6 p.m. on Thursday, July 5. The location will be announced.

THIS WILL BE A NON-VIEWING MEETING.

Thursday, May 31, 2007

TAA Annual Business Meeting June 5

NOTE CORRECTED ADDRESS!

The Tulare Astronomical Association will hold its annual business meeting on Tuesday, June 5 at 6 p.m. at 3124 W. Hillsdale Dr. in Visalia. All interested parties are invited to attend.

Map to the meeting.

Monday, May 28, 2007

Mars Joins Planetary Parade

Mars Joins Planetary Parade
by Dave Adalian
In my last column, I took you on a tour of the naked-eye planets, starting at sunset with elusive Mercury and ending in the early morning hours with blue Neptune. This time, another member of the solar system entourage joins the show while two others put in their best appearances of the year.

Tiny Mercury, a rocky planet just 3,000 miles wide, sits closest to the Sun, making it a bit of a challenge to view. But on Saturday, Mercury will be as far as it ever gets from the Sun as seen from Earth, a condition known as greatest elongation.

While Mercury, swift-footed messenger to the gods, will be visible for another couple of weeks, now, before it falls back into the fiery skirts of Sol, is the best time to see it. Look a bit north of dead west about an hour after the Sun retires to find it.

Don’t confuse Mercury with its brighter sister, Venus, also prominent in the west after sundown. This brightest of planets reaches greatest elongation one week after Mercury, but being farther from the Sun rides higher in the sky. Venus is a bright white, while Mercury, seen through more of Earth’s atmosphere, appears pink. Beside Venus are the twin suns of Gemini, Pollux and Castor.

Imagine a line through Mercury and Venus and follow it up the sky about the same distance as the current separation of Mercury and Venus. There, you’ll find Saturn, still sitting like a cosmic ball of yarn before the paws of Leo the Lion.

Saturn and Venus are headed for a close conjunction toward the end of June, so watch them night-to-night as grow ever closer together. Both will be gone from the sky by late July.

While the western trio is riding high, the King of Worlds, Jupiter, is rising in the southeast. By 11 o’clock it is well placed for viewing.

By 3 a.m., Neptune is high enough to be seen--if the sky is dark enough--but a chart is necessary to find it. (See link to a finder chart below.)

About an hour and a half later, just before dawn’s probing fingers creep above the horizon, look east to find Mars’ shining ruddily.

The Red Planet bears watching over the next year as it sweeps toward a close pass of Earth on Christmas Eve then fades back into the distant reaches of the Solar System, not to return again until mid-2009.

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This column appeared originally in the Visalia (Calif.) Times-Delta and Tulare (Calif.) Advance-Register on May 31, 2007.

Wednesday, May 23, 2007

Finding Neptune (and Uranus, too!)

Here's a link to a set of charts to help planet-hunters find the dimmest of naked-eye planets, Neptune. The charts are also good for finding Uranus, but you'll need at least a pair of binoculars to see it.

http://www.rasnz.org.nz/SolarSys/UranNept.htm

Thanks to the Royal Astronomical Society of New Zealand for the charts.

Sunday, May 20, 2007

Conjunction Images

Here's a shot of Venus and the new moon I took from my backyard in Visalia, Calif. around 8:45 p.m. PDT on May 19, 2007.

http://farm1.static.flickr.com/195/505508659_ef30c03152_b.jpg

Here's the best of the snaps I got of the Mercury-Moon conjunction two nights earlier from a local park about 8 o'clock:

http://farm1.static.flickr.com/224/505499552_1e4120f52c_b.jpg