COSMIC STRINGS ALERT: May Showers bring...um...Lots of Meteors? We Hope So!

That's right, dear readers...we've got a new meteor shower on our hands.  And we're hoping it's going to be a good one.

If you're already a meteor shower buff, you're familiar with the classics...the Perseids in August...the Geminids in December...sometimes the Leonids in November can put on one heck of a show.  But May is not usually a great time for meteors.

Hold on to your hat...we're hoping the May Camelopardalids will change all that.

If you're not a meteor shower buff, maybe you'd like a bit of an introduction.  Allow me!

Most of us have seen, or heard of, a shooting star.  Shooting stars have nothing to do with actual stars.  A shooting star is really a piece of rock entering the Earth's atmosphere from the vacuum of space.  When it does, the air of the Earth rubs against the rock.  As you might imagine, the rock heats up...and so does the air.  The streak of light across the sky that we call a meteor or a shooting star is actually glowing, superheated air left behind as the rock whips by.  If any part of the rock makes it to the ground, we call it a meteorite.  Such rocks are amazing finds and tell us a great deal about our solar system.

A bright meteor streaks across the sky over Texas.  This particular rock exploded, causing what is called a bolide - a very bright explosive flash.  Image courtesy the Astronomy Picture of the Day.

You can see a meteor on any clear night...if you're looking in the right place at the right time.  About 10 tons of material hits the Earth's atmosphere every day...but most of those rocks are the size of grains of sand.  They are destroyed on their way in without producing a meteor.  The ones we see are bigger...usually at least the size of a pea or larger.  They can come from anywhere, moving in any direction.  We call these sporadic meteors, because they can come from anywhere, anytime.

A meteor shower on the other hand, is a regular, predictable bunch of meteors that all seem to come from the same part of the sky.  This part of the sky is called the radiant of the shower...and the name of the meteor shower comes from the name of the constellation where the radiant is located.  So the August Perseids seems to come from the constellation Perseus...the November Leonids seem to come from the constellation Leo...you get the idea.  All these meteors seem to come from the same place and happen at the same time because the Earth is actually moving through a whole bunch of material left behind by the passage of a comet.

A composite image of the Geminid meteor shower showing numerous meteors coming from the same area of the sky.  These meteors did not actually all happen at the same time - this is a digital composite of many photographs taken on the same night.  Image courtesy of the Astronomy Picture of the Day.

Comets have long tails produced when the heat of the Sun warms up the ice a comet is made of and turns it to gas.  Comets can be pretty dusty, dirty objects...so when the ice gets turned to gas, all the dust and rock trapped in the ice is also released and left behind along the orbit of the comet.  If the Earth passes through this cloud of crud left behind...bam, you get a meteor shower as all those bits slam into the Earth's atmosphere.

Comet McNaught.  Note the big, messy tail.  All of that may be future meteor material.  Image courtesy NASA.

The comet debris that's causing all the fuss this May is a comet named 209P/LINEAR.  It's not a bright comet, and you can't see it tonight.  It orbits the Sun once about every 5 years, so it's shed lots of material over time.  Scientists think we're about to pass through a particularly dense patch of 209P/LINEAR material...TONIGHT!

That's right...tonight!  Overnight tonight, we might just have a spectacular new meteor shower.  Or...we might have a total dud.  The only way to know is to be outside tonight watching the sky.  There's a small chance this new shower might even be a meteor storm - when so many meteors streak across the sky at once that you can see multiple meteors every second!  By comparison, a really good meteor shower produces a few tens of meteors per hour.  So this could be the event of a lifetime!

Here's what to do to check out the May Camelopardalids:

• Go to bed early.  The best time to be outside for the meteors will be 1 - 3 AM early Saturday morning (on the East Coast of the U.S.) so you'll want to be ready to be awake in the middle of the night.
• Find the darkest sky you can.  If nothing else, make sure your house lights are all off, and ask your neighbors to turn off any outside lights they have.  The darker your sky, the more meteors you will see.
• Put the Big Dipper to your back.  The meteors will be coming from the constellation Camelopardalis the Giraffe, a very faint constellation in the Northern sky.  They will get brighter as they move away from the Giraffe, so putting North to your back will likely give you a better chance to see some meteors.
• Don't bother with a telescope or binoculars.  Meteors are easiest to see with the unaided eye!
• Dress as if it is 10-20 degrees cooler than it actually is.  You'll get cold really fast just standing still looking up.
• If you plan to watch a long time, bring a lawn chair out with you.  Especially something that reclines, so you can look up without straining your neck or back.

Best of luck with your meteor viewing! If you see any good views, please let me know in the comments!
Here's hoping for a massive meteor storm!
Either way...
Carpe noctem!
Kelly

Comet ISON Post-Mortem

*sigh*

No, it's not the holiday blues...it's the lack of a comet.

Sadly, it looks like Comet ISON did not fare too well in its first ever (and probably last ever!) trip around the Sun.  The comet was brightening dramatically as it approached the Sun, but then even before perihelion (it's point of closest approach to the Sun) the comet suddenly dropped in brightness...not usually a good sign.  It often heralds a breakup of the object.

Thanksgiving Day saw ISON directly behind the Sun from our view at perihelion...and then, it came back!  But sadly it was much, much dimmer than when it rounded the Sun, and then it proceeded to continue to dim rapidly.  Whatever is left of Comet ISON will not be bright enough to put on any kind of display in our skies this December.

A movie of Comet ISON plunging toward the Sun and then emerging, much diminished, on the other side.  Courtesy NASA and the SOHO Spacecraft.

Ah well.  It was exciting to hope for...but it wasn't meant to be.

We've got holiday fun to cheer us up though - Star of Wonder: Mystery of the Christmas Star and Laser Holidays are back in the planetarium for the rest of this year.  And of course, the December Star Party (December 14) will feature not only those two shows, but also a free concert by the United States Salvation Army Brass Band.  And hopefully the skies will be crisp and clear so we can enjoy the natural celestial show as well.

Still, a nice bright naked-eye comet would have been a wonderful early Christmas present.  Maybe if we're lucky, the Geminid meteor shower will consent to give us a few good meteors on December 14th, despite the nearly Full Moon.  Come join us and find out!

More from the world of astronomy in two weeks...until then...
Carpe Noctem!
Kelly

Fast Times Over East Coast Skies

Did you see it?

Last Friday, I got a phone call around 9pm from one of our local television stations.  They were getting lots of calls about some kind of meteor or something being seen in sky from all over the area.  Did I know anything about it?

Sadly, I'd been in my house all evening and missed the show.  But a quick internet search (oh whatever did we do before the internet!?) told me all I needed to know...people from Canada to Florida had seen a fireball...a dramatic meteor that lit up the skies all over the East Coast of the United States.

Two images of the East Coast Fireball from an astronomy camera in New York.  Images by Carl Fuller.

Since big sky rocks have been much in the news lately, I thought I'd use this week's post to define a few terms that have been tossed around of late.  I've got five of them for you, and once you've learned the differences between them, you too might get a phone call from a tv station, asking you for your expert opinion!  Okay, maybe not...but at least you'll know what these folks are talking about...and when they slip up and use the wrong word.

Let's start with the most common word: meteor.  A meteor is the streak of light created when a piece of material (usually rock and/or metal, but sometimes ice as well) comes in contact with the Earth's atmosphere.  The rock rubs against air molecules as it moves, generating lots of heat via friction.  This heat makes the air the rock passed through glow - and that's the streak of light we call a meteor.  The rock itself is not the meteor - in fact, we call it a meteoroid.

A meteorite is a piece of rock or metal that has traveled through the Earth's atmosphere from space and survived creating a meteor.  It crashes into the ground (sometimes creating a crater - a hole in the ground where it hit), and once the rock is on the ground, we call it a meteorite.  Finding a meteorite after seeing the meteor is very rare.  The vast distances involved often make it very difficult to judge where such an object may have landed.  There were early reports of the meteor on Friday having hit somewhere on the border between Maryland and Virginia, but this is extremely unlikely.  NASA has since analyzed the reported sightings of the meteor and they believe that any material that survived the passage likely fell into the Atlantic Ocean.

A meteorite nicknamed "Black Beauty."  The rock is believed to be from Mars, and landed in North Africa here on Earth.  The rock has been cut open and polished to reveal the inner structure.  Image courtesy NASA.

Okay, that's the big three.  But there are two more terms we need to come to grips with, and they've been tossed around a lot in recent days.  Some meteors are very bright - like the one that lit up the skies last Friday.  When a meteor is brighter than any of the planets (that is, brighter than Venus, the brightest object in the sky after the Sun and Moon), we call it a fireball.  Fireballs can be quite spectacular - often they show colors, since a chunk of material big enough to generate that much heat is going to be cooking lots of different materials - both on itself and in the air.  Such superheating can cause different molecules to glow with different colors of light.  Many people saw different colors in the trail of the meteor on Friday - and indeed, it was bright enough to qualify as a fireball.

Finally, the word bolide often comes into play when we talk about really bright meteors.  A bolide is a fireball that ends with an explosion - the rock becomes so superheated it detonates and explodes.  Such explosions are often accompanied by noises.  While several people reported seeing the Friday meteor fragmenting (bits and pieces may have been coming off), and some did report hearing noises accompanying the meteor's passage, the rock did not explode.  So it was not a bolide.  The recent fireball over the Siberian region of Chelyabinsk - that was indeed a bolide.  And a big one too.

So there you have it - you are now ready to speak with confidence about any shooting stars you might happen to see in the evening sky.  Did you see the one last Friday?  Leave a comment and tell me about it!

One more thing - I hope you got to see Comet PanSTARRS.  One of our wonderful volunteers did - and here's the photo to provide it!  Thanks to Mark Jablow for letting me use his beautiful picture.

A beautiful image of Comet PanSTARRS just after sunset.  Image by Mark Jablow.

Spring Break is coming for our area - so enjoy!  The museum will be open every day and we've got a full schedule of planetarium shows to keep the kids busy - hope to see you here next week!
Until then,
Carpe noctem!
Kelly

What's Up?

Well, hello.

It's been an eventful time in the astronomy business, thanks to a chunk of rock that decided to scare the living daylights out of a whole lot of people living in Siberia.  Amazingly, they seem to like air-bursting asteroids...once again, just like in 1908, a chunk of space rock exploded rather than impacting.  Since this one did so over a city, many people were injured when they rushed to look out their windows to see what the bright flash of light was.  Once the shock wave hit, the windows shattered, glass went flying, and many people were hurt.  But fortunately, I do not believe there were any deaths associated with the event.  But my goodness, it must have been quite scary to experience that first hand.  We talked about the 1908 event in our previous chat...when I wrote that I had no idea it would be happening again so soon!

The fireball over Siberia on February 15, 2013.

Anyway, let's turn ourselves to a calmer exploration of the sky.  It's been a while since I wrote a nice, simple post about things appearing in the skies above, so I think it's time to do that again.

The early evening skies are currently dominated by the largest planet in the solar system - Jupiter.  Shining brighter than all the visible stars, Jupiter is easily seen high in the southwest after sunset.  It's currently located in the constellation Taurus the Bull, right behind the bull's V-shaped face.  Taurus, of course, is facing off with Orion the Hunter, brightest constellation of our sky and easily visible high in the south.  So just by looking southward after sunset you should be able to quickly find the seven bright stars of Orion.  Use the belt of Orion (three stars in an almost perfect straight line) to find Taurus by following the line it makes away from Orion towards the right.  The belt will point you to the brightest star of Taurus, reddish Aldebaran.  This is the upper left point of the V of Taurus' face.  Right next to the V will be Jupiter, almost shocking in its brightness.

Following Orion's Belt to Aldebaran, the red right eye of Taurus the Bull.  In February of 2013, Jupiter is located between the V of Taurus' face and the Pleiades.

Jupiter is an incredible world.  Ten times bigger than our own planet Earth, Jupiter is a gas giant and the largest of the solar system's planets.  Even so, it is still much too small to be a star...Jupiter would have to be 10 times again as big as it is to become a star like the Sun.  The gravity of mighty Jupiter holds over 60 moons in orbit around the massive world, and even supports a tiny, thin ring system, completely invisible from Earth.  Only visiting spacecraft have the opportunity to see the rings of Jupiter, and they have fortunately sent lovely pictures back to us here on Earth.  Known from ancient times, Jupiter has long fascinated us, and it has been the target of numerous missions including the Voyager space probes and the Galileo spacecraft.  Another mission, Juno, is on its way, with a planned arrival in July of 2016.

The giant planet Jupiter.

The only other planet currently visible to us is Saturn, which graces the early morning sky before the dawn.  You'll see Saturn as a golden-yellow star-like object shining in the south before the Sun rises.  A pair of binoculars is all that is needed to reveal the lovely Saturnian rings, but you will need to hold them very steady.  A tripod will serve you well.  And be prepared to get up quite early - 5AM is the best time to see Saturn these days.  If you'd rather see it at a more convenient time...wait a few months.  Later in the year, Saturn will become an early evening object rather than an early morning one.

Saturn and its amazing ring system.

So everyone take a deep breath, relax, and enjoy the sky.  I promise, despite the events of recent days, the world is not coming to an end.  Hopefully the sky will give us a few days to catch our breath before the next potential big event - Comet PANSTARRS.  If the comet becomes something worth venturing outside to see, I'll put out a Cosmic Strings Alert to let you know.

Barring that, I'll see you in two weeks!
Carpe noctem!
Kelly

DON'T PANIC!

I hope you found those to be nice, friendly letters.

At any rate, truly, there is no need to panic.  Friday will come and go, and we will NOT be destroyed by a giant rock from space.  Truly, we won't.

You've probably heard about asteroid 2012 DA 14 (yes, that's really the only name it has!), which will be making an extraordinary pass by Earth this Friday.  In fact, here's the official details:

Asteroid: 2012 DA 14
Date: Friday, February 15, 2013
Time: 2:24PM EST
Distance at closest approach: 17,200 mi from Earth
Size of asteroid: 164 ft. wide
Composition: Stone
Chance of impact: ZERO

Did you read that last bit?  There is a ZERO chance that 2012 DA 14 will hit the Earth this Friday.  Zero. Zilch.  Nada.  None.  No chance at all.  Not even if it happens to hit a satellite (which is terrifically unlikely) - it cannot possibly "bounce" off a satellite and hit the Earth.  It simply will not happen.

So, what will happen?

This asteroid will zip past our planet a bit inside the orbit of the geosynchronous satellites.  Those satellites handle things like weather and communications, among others.  The rock will go outside the GPS satellites, however.  So while it will be close to us...it won't be that close to us. 

Some folks are hoping to be able to see this rock as it zips past.  That will be extremely difficult, for several reasons.  First of all, it will be moving a good clip...17,400 mph, in fact.  That means it will move across the sky about 1 degree per minute - tough to track, that's for sure.  And you'll need to track it, because it won't be visible to the unaided eye.  Even coming so close, the rock is so small, you'll need at least a pair of binoculars to see it at all.  And one other small problem...you'll need to be in the middle of the Indian Ocean.  Sumatra will get a nice view.  So...not much of an event here in the U.S.

But now, let's tackle the juicier question...what if the scientists are wrong? (They're not.)  What if it does hit us after all?  (It won't.)

Okay, let's consider it.  What would happen if 2012 DA 14 hit the Earth?  Lucky for us, we've got some good models for that...because they've already happened.  (insert gasp of surprise here)

2012 DA 14 is about the same size as the asteroid that impacted the U.S. some 50,000 years ago just outside of what is today Winslow Arizona.  That meteor struck the ground and blasted a hole in the Earth 4,000 feet in diameter, and 570 feet deep.  You can visit the crater today - it's called Barringer Meteor Crater.  

Barringer Meteor Crater in Arizona

Now, the meteor that created Barringer Meteor Crater was made largely of iron.  2012 DA 14 is a stony object.  So it would not impact with nearly the same amount of force.  In fact, it probably would not impact at all...the stress of enter Earth's atmosphere at a high rate of speed would likely shatter the rock before it ever made it to the ground.  We've got a model for that too.  On June 30, 1908, a meteor about the size of 2012 DA 14 exploded over the Podkamennaya Tunguska River in Siberia.  The blast leveled 830 square miles of forest, and likely measured 5.0 on the Richter scale.  The energy of the blast was about 1,000 times as much as that from the atomic bomb dropped on Hiroshima by the United States.  If a blast like this occurred over a major population center, the results would most certainly be unpleasant.  But not Earth destroying, by any means.

Trees leveled by the Tunguska explosion in 1908.

 
So...long story short....Friday will be a great day for scientists who study asteroids...and maybe even for a few amateurs who can get photographs of our celestial visitor...but for most of us, it will simply be another day on planet Earth.

Until the next close shave...
Carpe noctem!
Kelly

Resolved

Happy New Year everyone!

I hope your 2013 has gotten off to a great start.  For many of you, that may mean making some New Year's Resolutions.  I've never been much for them myself...I often find my enthusiasm for them wanes rapidly after the New Year's celebrations are over.  But if you find yourself in need of some resolutions this year...I humbly present to you these recommendations.

New Year's Resolution #1: Resolve to be more in touch with the universe around you.
Back in the day, humans were very in touch with the universe.  It was our clock, our calendar, a source of wonder and the home of the gods.  Today, many of us go through our lives without ever taking the time to look up.  Make it a mission to spend some time under the stars this year.  We can help!  Every second Saturday of the month, the museum hosts a Star Party.  The first one in 2013 is on January 12 - we'll look forward to seeing you!  Star Parties are FREE and everyone is welcome.

New Year's Resolution #2: Resolve to see some shooting stars.
Virtually every year there's a really good meteor shower to see...and 2013 is no exception.  This year, the Perseids are on tap to put on an excellent show, and that's great news for all you folks who hate having to be outside in the freezing cold weather to do your stargazing!  The Perseids peak on August 12th, so you'll be able to spend a balmy evening in your shorts and t-shirt watching "stars" fall from the sky!  On that night, the Moon will be just past first quarter and will set early, so you can drag out a lawn chair and stare upwards for the rest of the night with nothing to dim your view of the heavens (just get away from any city lights near you).  Some models are predicting a bump up in rates for the Perseids this year, so this one could be pretty neat.  Remember - no telescope or binoculars are needed; the more sky you can see, the better.  Put your back to the constellation Perseus and enjoy the show.

A bright Perseid meteor streaks across the sky.  Image by Stefano DeRosa

New Year's Resolution #3: Resolve to use that telescope in the closet to see something cool.
So many of us have a telescope sitting somewhere gathering dust.  Well, this year, you need to get it out and have it set up and ready to go on Friday, October 11, no later than 11:30pm.  Point it at Jupiter as early as you can, and watch.  Slowly but surely, the shadows of not one, not two, but THREE of the largest Jovian moons will make their way across the giant planet.  A triple eclipse for Jupiter...a triple shadow transit for those of us here on Earth.  It should be a lovely sight in a good sized telescope.

A rare triple shadow transit on Jupiter on March 28, 2004.  Image by Sid Leach.

New Year's Resolution #4: Resolve to watch a rocket take off.
If you can get to Cape Canaveral on November 18th, you'll have the opportunity to do it in person!  If not, tune in NASA TV and watch the launch of MAVEN: the Mars Atmosphere and Volatile EvolutioN mission.  MAVEN will study the Martian atmosphere to see how the loss of materials to space has affected Mars over its long history.  Launches are always cool to watch, and this one should be no different.

An artist's conception of the MAVEN spacecraft orbiting Mars.  Courtesy NASA.

New Year's Resolution #5: Resolve to see the comet of the century...maybe...
There's already a buzz in the astronomical community about Comet ISON - it could be the most amazing comet North America has seen since Hale-Bopp...or it could fizzle.  Currently located beyond Jupiter, this newly-discovered comet is making its way toward a close encounter with the Sun.  If it holds together, it could put on an incredible show during the last two months of 2013.  Early predictions indicate that Comet ISON could reach negative magnitudes (bright like Jupiter or Venus), or even outshine the Moon (2nd brightest object in the sky!) and have a gorgeous tail visible to the unaided eye for weeks or even months.  Other early predictions say it could completely collapse under the pressure of the Sun's light and heat and be a total washout.  The only way to find out will be to watch the skies.

The orbital path of Comet ISON.  Courtesy NASA.

So there you have it - five astronomical things to resolve to do in 2013.  Whatever you choose to do, may 2013 be a year full of joy for all of us.

Carpe noctem!
Kelly

The Most Wonderful Time of the Year

Hooray!  The election is over!

Okay, sorry, I couldn't help myself.  Whether your favored candidate won or lost, I think we can all agree it's been a long and rough election season.  I confess I am happy to be done with political ads, phone calls, and mail.  The holidays are just around the corner, and that is indeed my favorite time of year.

But before we get into the holiday season, we've got something fun coming up this Saturday!  Yes, it is once again time for our monthly Star Party and Laser Light Night here at the Virginia Living Museum.  While the flood damage has stopped us from using our lower level, the observatory is in great shape, and the planetarium is running just fine.  So we hope you'll be able to join us for some great sky watching and planetarium and laser shows this weekend!  Here's a quick preview of what we'll be looking at in the night sky (weather permitting, of course!).

Actually, I can pretty much sum it up in one word - Jupiter.  The largest planet of the solar system has once again returned to the evening skies and we cannot be more excited!  Mars (technically) remains low in the southwestern sky after sunset, but let's face it...it's nothing to write home about.  Even on the flattest western horizon you'll have difficulty finding our little neighbor planet.  It's not very bright, it's a dull orangey color, and at only half the size of Earth it's not particularly big, even in a telescope.  On the other hand, Jupiter is the second brightest of the planets (behind only Venus, now dominating the early morning skies), at ten times bigger than Earth it shines like a brilliant white star and shows amazing amounts of detail in a telescope, and rises in the early evening to then spend the rest of the night crossing the sky.  You can bet we'll have a telescope or two trained on Jupiter throughout the star party.  Join us to see how many Jovian moons we can spot, whether the Great Red Spot is facing towards us, and how many dark cloud bands can be seen on the face of the mighty planet. 

Jupiter, largest planet of the solar system.  Courtesy NASA

We often spend time hopping around various deep sky objects as well...galaxies, globular clusters, open star clusters and nebulae are frequent sights in our eyepieces.  There's also a chance you might see something impressive without even needing a telescope.  The North Taurid meteor shower will peak in the wee hours of Monday November 12...but it's not unthinkable that we might see a few early shooting stars on Saturday November 10.  The Taurids occasionally produce some brilliant fireballs, so if we do see a meteor, it's likely to be a doozy. 

A Taurid Fireball from 2005 photographed in Japan.  Courtesy NASA.  Photograph by Hiroyuki Iida

In the planetarium we'll be featuring the night sky and lots of great music.  At 7:30pm, I'll take you on tour of the evening sky with Virginia Skies.  Once you've seen the stars in the planetarium, step outside and check out the real thing!  Bring the kids for our 8:30pm laser show: iPop.  It's a great mix of some of today's hottest pop stars...including some of those super-popular teens from the Disney Channel and Nickelodeon.  Hoping for some music more to an adult's taste?  No problem - stick around until 10pm for the psychedelic sounds of Laser Doors...and keep the trip rolling on with Pink Floyd's Dark Side of the Moon at 11:30pm.  It all kicks off at sunset with FREE observing of the night sky...shows are $6 person, or any two for $10.  Members always get their tickets half price.

Okay, in the interests of full disclosure...there's another reason why I'm so excited for the star party this month...it's happening on my birthday, which I share with two wonderful people...a dear friend of mine (Happy Birthday, John David!) and Martin Luther, architect of the Reformation.  I suppose I could nail my doctoral thesis to my church door...nah, it wouldn't make much sense...plus the doors are made of glass anyway...

Until next time...
Carpe noctem!
Kelly

So What's on Your Mind?

I came to the shocking realization the other day that I've been writing this blog for over a year now.  It certainly hasn't seemed that long to me.

One of the things I was hoping would happen as I began this blog hasn't really materialized yet.  I'd really love to be fielding your questions...talking about the topics that interest you, my readers, the most.  Anyone is welcome to leave a comment on any post - even if your question has nothing to do with the post!  I'll be more than happy to answer your question...and I might even make it the topic for the next blog post.  So please - ask away!

In the hopes of inspiring some new questions, let me share with you the answers to the questions I get asked most frequently.

Who invented the telescope? -OR- Galileo invented the telescope, right?

Actually, Galileo Galilei did many amazing things that advanced our understanding of the solar system we live in, but inventing the telescope was not one of them.  He was the first person to use a telescope for astronomical purposes, turning his simple instrument on the Moon, the Sun, Jupiter, Venus and even Saturn.  But credit for inventing the telescope is generally given to Hans Lippershey, a Dutch lensmaker. 

Hans Lippershey.  Courtesy Wikipedia.

What was that bright thing I saw last night/morning in the east/south/west?

About 99% of the time, the answer to this question is one of the 5 naked-eye visible planets: Mercury, Venus, Mars, Jupiter or Saturn.  Most often, it's Jupiter or Venus, as they are the brightest of these five, with Venus being the brightest object in the sky after the Sun and the Moon.  The planets are generally brighter than the stars near them, and they won't twinkle the way the stars do, making them stand out against the background stars.  These days, Mars is extremely low in the southwest in the early evening.  In the early morning skies, you'll find Jupiter high in the south and Venus mid-way up in the east around sunrise. 

On rare occasions, the answer to this question is Sirius, the brightest star in the nighttime sky.  You'll find Sirius in the winter sky, easily located by following Orion's famous belt to the left.  Sirius will twinkle quite a bit, and it is impressively bright.

Sirius by the Hubble Space Telescope.  The small white dot in the lower left of the image is a tiny white dwarf companion to the main star.  Courtesy NASA.

Where can I buy a quality telescope?

Some camera shops still carry high quality telescopes, but my personal favorite place to purchase observing equipment is online from Orion Telescopes.  They carry an excellent "house" brand, plus the usual players like Meade and Celestron.  Their customer service is excellent, and their prices are quite reasonable.  One word of caution - be wary of purchasing anything manufactured by Meade.  This once-excellent company was bought out several years ago and now offers little or no customer service, and has become increasing difficult to deal with.  Stick with Celestron or Orion's own stuff. 

Where to NOT buy a telescope (especially with the holiday season just around the corner) is any big box store of any kind.  Most "Christmastime" telescopes are cheap, fall apart quickly, and use inferior optical elements.  A good rule of thumb - if the telescope costs less than $150, you are probably going to be disappointed.

When is the best time to see shooting stars in the sky?

Shooting stars are actually meteors - chunks of rock from space coming in to the Earth's atmosphere at high speed.  When they make contact with the Earth's air, the friction generated by the rocks passage causes the air it passes through to glow - making the streak of light we call a shooting star.  While random bits of rock can plunge Earthward at any time, Earth does regularly pass through rocky debris left behind by the regular orbiting of comets.  Such times are called meteor showers, and they are the best times to go out and look for shooting stars. 

The best meteor showers of the year and the rough dates they peak on are:

The Quadrantids  January 4
The Perseids       August 12
The Orionids       October 21
The Leonids        November 17
The Geminids      December 14

I say rough dates because the exact peak date and time changes every year.  In general, the best time to be outside to look for meteors is around 2AM as the combination of the forward motion of the Earth in its orbit and the rotation of the Earth carrying us in the same direction make it more likely that meteors will be visible.  Astronomy is not a hobby for those who like to go to bed early. 

My birthday was yesterday.  Why couldn't I find my sign in the night sky?

Your "sign" is the constellation in which the Sun was located on your birthday.  During the course of the year, the Sun appears in the sky against the background of the zodiac stars, which are part of 12 (13 if you count Ophiuchus, which the ancients really didn't) different constellations.  Today's astrological signs are generally determined by the way the sky looked 6000 years ago, when astrology was getting its start.  In 6000 years, the sky has shifted a fair bit, mostly because very few motions of the solar system actually occur in even numbers of hours or days or months or years.  So what the newspaper says is your "sign" is actually probably not where the Sun really was on the day you were born. 

For example, I was born on November 10.  According to classic astrology, my sun sign is Scorpius the Scorpion.  However, on the actually date I was born...the Sun was located in the constellation Libra the Scales.  6000 years makes a measurable difference in such things.

However, none of that has to do with why you can't find your sun sign constellation in the sky on your birthday.  You can't find it at night, because it isn't there!  By definition your sun sign is in the daytime sky on the day you were born - because it's near where the Sun is on that day.  So if you want to see your sun sign in the sky...wait for 6 months after your birthday.

So what astronomical question have you been longing to ask?  I await your comments eagerly.

Until then,
Carpe noctem!
Kelly

Smoke on the Water and Fire in the Sky

Well, I don't know about the smoke on the water part, but last Sunday in Nevada and California there was definitely some fire in the sky.

It's now fairly certain that the explosion reported by so many folks in those two states was a bolide, or a fireball.  Fireballs are large meteors that are generally very bright, and are usually accompanied by a good deal of noise.  Most often they explode in the air - a result of the stress of passing through the Earth's atmosphere.  But what is a bolide, really?

Simply put, it's a shooting star.  A very impressive one.

Shooting stars are not actually stars.  They are meteors - rocks from space which enter the Earth's atmosphere.  Most are extremely tiny - like grains of sand or dust.  The friction caused by all that air rubbing against the rock actually makes the air glow - that's the streak of light we see and call a shooting star.  Tiny dust-fragments never get that far - they disintegrate and are gone before they can heat up enough air for us to see.  Larger chunks make a distinct streak of light, but they actually don't make it very far into our atmosphere either before they too are destroyed.  Big chunks, though, can do some amazing things.

A map showing the location of the April 22nd fireball.  Courtesy spaceweather.com

The fireball this weekend was clearly seen in daylight.  When the meteor finally burst apart from the stress, it was pretty close to the ground - maybe about 5 miles up.  If it had been higher up, there would not have been so many reports of loud booms.  Based on information gathered from eye witnesses, it's likely that the meteor which caused all the excitement was about the size of a minivan when it entered the atmosphere.  The energy of the explosion has been estimated at about 3.8 kilotons of TNT, so this was a pretty big deal.  Since it exploded above the ground, there was little actual damage, but it's possible some pieces of the meteor may now rest on the ground.  If these meteorites can be found, they would be quite special, as it is rare to be able to so accurately pinpoint the event that a meteorite came from.

A picture of the Nevada/California fireball of April 22.  Credit: Lisa Warren

So don't forget to keep looking up, even in daylight.  You never know just what you might see!
Carpe noctem et diem!
Kelly

2012: A Year of Astronomical Proportions

Happy New Year everyone!  Once again, I shall ride the current bandwagon, and this post will feature a list of things coming in 2012 that, if at all possible, you should not miss.  Mark these five dates on your calendar now!

March 3, 2012: The Opposition of Mars
No, this has nothing to do with us declaring war on the Martians.  A planetary opposition occurs when a planet is seen exactly opposite the Sun from the Earth, meaning that the planet will rise at sunset and set at sunrise, remaining visible in the sky all night long.  This also means the planet is generally closer to the Earth, as it is on the same side of the solar system as we are.  For Mars, this is a wonderful thing.  Mars has a highly elliptical orbit, and that means that opposition brings our little red neighbor (Mars is only half the diameter of Earth) close enough that details can be seen on the surface with a good telescope.  With a really big telescope...well...you can just imagine.

Mars during the 1997 opposition.  Courtesy NASA, HST & STSci.

This year's opposition is a poor one - even at close approach, Mars will not be as close as it has been in years past - and future oppositions will be better than this one too.  But it's worth seeing the planet nonetheless, even if you don't have a telescope.  Mars is usually a dull orange-ish star in our sky, and not very noteworthy.  But during opposition, Mars will rival Sirius, the brightest star in the nighttime sky, in brightness - a stirring sight for sure.  Right now, Mars rises late in the evening and is visible high in the south around sunrise.  As the year progress, watch for it to rise earlier and earlier in the evening, making viewing this beautiful planet a pretty simple feat even for those who don't like staying up late.  Want to see Mars through a telescope?  Come visit us for our monthly Star Party & Laser Light Night on March 10th.  Mars will be a week past opposition, but still looking great!  Don't miss it!

May 20, 2012: An Annular Solar Eclipse
This one is especially for any readers I might have in California, Utah, Nevada, Arizona, New Mexico and Texas.  On May 20th, as the Sun is setting across those states, the Moon will glide in front of the Sun.  But the Moon will be too far away to cover the entire disk of the Sun, resulting in what is called an annular solar eclipse.  Most of the Sun's disk will be covered, with only a ring of solar surface visible around the Moon.

The Sun during the annular solar eclipse of January 15, 2010 by Mikael Svalgaard.  Courtesy Astronomy Picture of the Day.

IMPORTANT NOTE: Do NOT attempt to view the eclipse without proper eye protection!  Doing so can result in serious damage to your eyes, even blindness.  The Sun's surface, even only a small portion of it, is incredibly bright.  Never look at the Sun with unprotected eyes.  GOOD NEWS: You don't need a telescope to view this amazing event!  The best thing to get is a pair of eclipse glasses - they'll likely be available at your .local science center as the eclipses gets closer, or you can order them online.  Or, for a quick, inexpensive solution - buy a piece of Shade #14 Arc Welder's Glass from a local hardware store, and look at the Sun through that.  Make sure you get Shade #14 - no other shade will work.  Once you've protected your eyes - go outside about an hour before sunset (check your local paper for exact times for your area!) and watch the Sun as it goes down.  It will be an amazing view.

June 5, 2012: The Transit of Venus
Okay folks, this is the big one.  If you see no other astronomical event this year - see this one.  Why?  Because, quite literally, you will not have another chance to do so in your lifetime.  There will not be another transit of Venus for 105 years - so this is your one and only chance.

A transit is kind of the opposite of opposition - in this case, a planet is crossing in front of the disk of the Sun as seen from the Earth.  Naturally, we can only see transits of Mercury and Venus - the only two planets which lie closer to the Sun than we are.  You'd think these would happen all the time, but like eclipses, the geometry doesn't always work out.  Most times a planet passes above or below the Sun from our perspective.  But every so often the geometry is perfect, and we get to see a planet silhouetted against the brilliant face of the Sun.

The 2004 Transit of Venus photographed by Stefan Seip.  Courtesy Astronomy Picture of the Day.

The transit of Venus this June will occur close to sunset for us, and you can bet we'll be watching here at the Virginia Living Museum!  Stay tuned for more information on our Transit of Venus event.  While the transit will be visible unmagnified with suitable eye protection (remember the warning above!), it will be better through a telescope.  If you're local to Hampton Roads, plan to come join us!

December 13, 2012: The Geminid Meteor Shower
Meteor showers are always fun, and there are usually a couple good ones each year.  But if you're only going to bundle up and sit outside for several hours once in 2012, wait until the December Geminids.  The Moon will be new, making this a perfect night for stargazing in general.  The shower will peak around 7pm local time, meaning you don't have to go outside in the middle of the night to enjoy a good view.  Simply find a dark location (the fewer lights the better!), set up a comfortable lawn chair (laying back so you can see a lot of the sky without straining your neck is best), pile on some blankets and enjoy the show.  The meteors will seem to come from the constellation Gemini the Twins, so if you can place those stars at your back, so much the better.  You can watch until the wee hours of the morning if you like...2am is often a good time to see meteors as our part of the Earth will be turning into our direction of motion, making for good meteors!

A 2011 Geminid meteor over Iran photographed by Arman Golestaneh.  Courtesy Astronomy Picture of the Day.

December 21, 2012: The End of the World
Okay, this one really isn't an astronomical event.  In fact, it's not really an event at all.  Well, it is the Winter Solstice, but you can't really "watch" that event unless you plan on setting up a camera and waiting a year.

 The Analemma over the Porch of Maidens in Athens, Greece as photographed by Anthony Ayiomamitis.  Courtesy Astronomy Picture of the Day.  The Winter Solstice is the Sun's lowest point in the sky. 

But you're probably aware of the numerous predictions of doom and gloom for our planet surrounding this date.  I always love it when such things come up, because it gives us a great opportunity to educate folks about science and how it works...and how it doesn't.  Want a primer on what all the fuss is about?  Join us for 2012: The End of the World? NOT!, a brand-new planetarium show which will be featured all year at the Abbitt Planetarium.  And stay tuned for more information about our End of the World Party, currently in the planning stages. 

So there it is - what not to miss in 2012.  May it be a year of astronomical proportions for all of us!
Carpe noctem!
Kelly

The Month They Call November

My friends, if you know the song that the title references...you know some obscure music.

But I confess November is my favorite month.  I can't help it.  I love the fall, with cool temperatures and beautifully colored leaves.  I love the early sunsets and long dark nights, growing ever longer as the month progresses.  I love the holiday season, with Thanksgiving leading right into Christmas.

Okay, you got me.  I also love November because I was born in it!  ;D  So let's talk a little about what you can expect to see in the skies during this wonderful month.

You've got some great opportunities for planet watching this month.  Mercury and Venus are putting on a lovely show in the early evening sky, just after sunset.  The trick is you need a super-flat western horizon to see them.  But oh boy, the view is worth it!  If you can get outside on the evening of the 13th or 14th, Mercury and Venus will be very close to one another, and about as far from the Sun as Mercury is going to get for a while.  Give it a try - seeing Mercury even with the unaided eye is something most people have never done!  Let brilliant Venus guide your eye (it is the brightest object in the sky after the Sun and Moon).  Mercury will be a smaller star-like object within 2 degrees (about 2 fingers-width) of the bright planet, closer even than in the image below.

Venus and Mercury at sunset on April 5, 2010 by Manu Arregi Biziola.  Image from Astronomy Picture of the Day.

Jupiter also graces the evening skies, looking like a stunning bright white star.  The largest planet in the solar system is rising near sunset, and so it is visible nearly all night long.  You've probably seen Jupiter in the evening sky already - it's pretty darn hard to miss!  It's hovering around between the constellations Aries, Pisces and Cetus...and none of those constellations have any bright stars in them.  So Jupiter is shining all alone in a fairly dark area of sky, which only makes it look that much more impressive.  To give you a sense of how bright Jupiter is, check out the picture below. 

Jupiter seen with the Full Moon in 2009 by Jens Hackman.  Image from Astronomy Picture of the Day.

Even with a Full Moon ablaze in the sky, Jupiter stands out quite nicely.  Imagine how amazing it will look when all alone!  We'll be observing Jupiter for sure at our star party this weekend.  You haven't really seen Jupiter until you've seen it through a telescope!  Observing begins at sunset on November 12th here at the Abbitt Observatory, and as always, it's free!  Here's hoping for clear skies!

If you're hoping to see Saturn or Mars, you'll need to go outside during the pre-dawn hours...and now that we've changed back to Eastern Standard Time, that means being outside in the very early morning...perhaps around 4:30AM.  Your reward for bring an early riser will be a view of the Red Planet shining in the south, and the golden-yellow "star" of Saturn appearing low on the eastern horizon just before the Sun.  It's interesting to see these two planets in the same sky, since they both exhibit such distinct colors.  Towards the end of the month, they'll even be about the same brightness, so see if you can notice the color difference between Mars and Saturn.  Even if you can't, they will both be quite beautiful, as you can tell from the image below.

Saturn (left) and Mars (right)  flank the Beehive Cluster in June of 2006 by Tunc Tezel.  
Image from Astronomy Picture of the Day.

Maybe you prefer something more showy than just planets hanging around in the sky.  Well November can oblige.  The annual Leonid meteor shower peaks on November 17th every year, and this year is no exception.  You may remember the Leonids from the meteor storms of the early 2000s.  While no storm is predicted for this year, we will still pass through a stream of debris left behind by Comet Tempel-Tuttle, resulting in a higher-than-normal rate of meteors being visible all coming from the direction of the constellation Leo.  Since Leo rises around midnight at this time of the year, put the East at your back and watch for shooting stars any time after sunset on November 17th.  Your best view is likely to be had during the wee morning hours of November 18th.  Since the Moon will be on the wane, it too will rise late, giving you some time to see the meteors against the backdrop of a dark sky.  No telescope required for this event - you want to be able to see as much of the sky as possible.  Patience is the key with meteor showers - set up a lawn chair and watch the sky.  The longer you watch the more meteors you will see as your eyes adjust to the darkness.  Enjoy!

The 1999 peak of the Leonid meteor shower by Juan Carlos Casado.
The image is a 20 minute exposure and captured several meteors.

Image from Astronomy Picture of the Day.

Until next time...
Carpe noctem!
Kelly

The Dog Days are Back

Hey everyone!

Well, here we are again.  It's August.  The weather is hazy, hot, and humid.  Going outside for more than about 4 seconds results in sticky wet clothes, lots of sweat, and generally feeling nasty really fast.  It is not, by any stretch of the imagination, an astronomer's favorite time of year.

And yet, there's still stuff to talk about, even if we'd rather stay inside while we do it!

Traditionally, August days are called the Dog Days of Summer.  The phrase refers not to the lolling tongues of dogs desperately trying to stay cool, but to the brightest star in the nighttime sky, Sirius.  It's the brightest star in the constellation Canis Major, the Big Dog, and therefore it is often called the Dog Star.

The star Sirius.  NASA

The ancient Greeks noticed that in August, when things were getting pretty hot, the star Sirius rose in the East just before the Sun, meaning that Sirius shares the sky with the Sun virtually all day.  Since Sirius is so bright, the Greeks figured it must be pretty close, and the extra heat in August was caused by Sirius adding its light and heat to the powerful rays of our own Sun.  The Romans and the Egyptians also shared this same belief - and in fact, the Egyptians were especially attentive to Sirius, as the Dog Days occured just before the annual flooding of the Nile.  Score one for the ancients, no?

Well, the ancients were unaware of just how far away stars are.  They were correct in their assumption that Sirius is pretty close to us - it's about 8 light years away, or 47 trillion miles.  As close as that is as stars go, that's still much, much too far away for Sirius to have any kind of effect on our weather.  The Sun is only 93 million miles away, and that's the cause of our weather changes.  The heat at this time of year is the result of the Earth's tilt - the Northern Hemisphere is tipped towards the Sun during summer, giving us long days and lots of intense sunlight.  No additional stars required.

Don't feel too bad for the ancients.  They might not have been right about everything, but they did hand down some wonderful stories and ideas that are still fun to share.  Take the exciting tale of Perseus, son of Zeus and legendary hero.  His story is best known today as the campy classic film Clash of the Titans (trust me, for maximum enjoyment, stick to the original, not the sad modern remake).  You might want to rent it around August 12, and enjoy a midnight movie at home.  When the film is over, head outside and look up.  You should be just in time to catch some of the annual Perseid meteor shower, which will peak around 2AM on the morning of August 12.  Meteors will seem to come from the direction of the constellation Perseus, so put him at your back if you can. 

The constellation Perseus.  NASA

Staying away from bright sources of light will also help...and the best way to enjoy any meteor shower is from the comfort of a lawn chair so you can watch the sky as long as possible.  The beautiful streaks of light you see are bits of Comet Swift-Tuttle disintegrating in the Earth's atmosphere.  Want more information on meteor-watching.  Come by the museum any day at 1:30PM for our Virginia Skies program - one of our staff astronomers will be happy to help you with your questions about meteor showers, or any other astronomical topic!

And, just in case you were wondering...that bright golden star in the West in the early evening is Saturn, still nicely visible.  Out a bit late and noticing a bright white star in the East?  That's Jupiter.  Enjoy!

Carpe noctem!
Kelly