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

It's a bird...it's a plane...it's a COMET!

Greetings astronomy fans!

Well, it's here!  The first of the two comets touted to put on great shows in our skies this year.  Comet PanSTARRS has arrived!

Yep.  It's here. 

Okay, sorry if I sound a little bummed.  But I'd give my right arm to be in the southern hemisphere.  They've had extraordinary views of Comet PanSTARRS for quite some while now...and Comet Lemmon too!  And Comet McNaught last year!  It's been a veritable comet bonanza for our friends down under...and dang it, I am jealous!

But all is not lost here in the great white North.  I tried to see Comet PanSTARRS last night, but lingering clouds and light pollution made it impossible (I did see a fantastically young crescent Moon, however - youngest I've ever seen!).  But it should get easier tonight, as the comet is inching itself away from the Sun day after day.  That's going to both help (further from the Sun means it will be in a darker sky and easier to see) and hurt (further from the Sun means the comet itself will be a dimmer object) - but over the next couple of days we'll have our best chance to see this little interloper.  So how do we do that?  Here are some tips!

• Find a location with as little light pollution as possible.  Get away from as many city lights as you can.
• This same location also needs to have as flat a western horizon as possible.  The more sky you can see to the west, the better.
• Start looking to the west just after sunset.  Focus your attention to the left of the brightest sunset glow.
• Look for a very slender crescent Moon.  It will be up and to the left of the sunset.
• Once you see the Moon, look between the Moon and the sunset glow for the comet!

A finder chart for Comet PanSTARRS.  Courtesy space.com.

Trust me, it will not be easy to see.  Binoculars may come in handy, but use them carefully and ONLY after the Sun has completely dipped below the horizon.  Seeing a comet is not worth losing an eye for.

A camera will help a lot, if you are confident enough to try it and have one of those "old-fashioned" cameras you can force to leave the shutter open for more than a tenth of a second.  Witness the power of the two-second exposure:

Comet PanSTARRS from Louisiana on March 12.  Image by Mike B. Courtesy Cloudy Skies Telescope Reviews.

So, sadly, Comet PanSTARRS is fainter than we hoped it would be by now.  Comets are tricky beasts - chunks of ice and rock left over from the early days of the solar system's formation.  When they dive close to the Sun like this one has, the ices warm and turn directly to gas, creating an often intricate and beautiful tail of materials stretching for millions of miles.  But the brightness of a comet is determined by the amount of ice as compared to rock (ice is shiny and bright and rock is dull and dim), so there's never really a good way to know if a comet is going to be bright or not...until it arrives.  Also, this appears to be Comet PanSTARRS first (and possibly only) trip close to the Sun, so the intense heating may have driven all the ices off, leaving not much left for us to see now that the comet has rounded the Sun.

I wish you all the best of luck in your efforts to see Comet PanSTARRS...and never fear, there's still Comet ISON to come later this year.  It's being touted as the "Comet of the Century" - but of course, we'll just have to wait and see.

Until next time,
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 Year in Review

It's that time of year, isn't it folks?  Everyone is doing a "Year in Review."  Well, who I am to miss that bandwagon!  So in this final installment of Cosmic Strings for 2011, I give you my personal five favorite astronomy stories of 2011.  Enjoy!


The Total Lunar Eclipse of June, 15, 2011
2011 was a banner year for eclipses...we had 4 solar and 2 lunar eclipses.  I wish we could have seen them.  Sadly, all 6 eclipses were basically not observable from the United States.  But many of our international friends got to see some amazing sights...and of the the eclipses this past year, the June 15th lunar eclipse was likely the most wonderful.  It was a rare lunar eclipse where Moon passed through virtually the exact center of the Earth's shadow, making it not only a very long eclipse (the total duration was almost 6 hours!), but also one where the Moon took on a fabulous color.

The lunar eclipse of June 15, 2011 by Javier Algarra.  Courtesy Astronomy Picture of the Day.

Atmospheric scientists can tell a great deal about the Earth's atmosphere from lunar eclipses.  The reddish color of the Moon during a lunar eclipse is caused by sunlight bending through the Earth's atmosphere and striking the lunar surface even when it is in the shadow of the Earth.  Usually only deep reddish light gets through, but depending on the various particulates found in the atmosphere of the Earth, the Moon may appear bright red, copper colored, and even a yellowish-orange.  If you got to see this wonderful eclipse, count yourself lucky!

The Launch of Curiosity
It might seem odd to include a spacecraft launch in my list, but I can't help it.  I'm excited!  Another plucky robot has successfully made it off the Earth and is on its way to Mars.  Launch is a dangerous time...second only in danger to landing.  So Curiosity still has a long way to go before it can get to work...and the greatest danger lies ahead.  Mars has been a tough planet to explore...about half of the missions headed there have ended badly.  And yet, Mars is well worth the effort, as it is the place in the solar system most like the Earth.  If life is, or ever was, present in the solar system beyond the Earth, Mars is the most likely place for it.  The Spirit and Opportunity rovers have shown us definitive proof that Mars was wet in the past and likely still has a fair amount of water.  Perhaps Curiosity will be able to provide definitive evidence of Martian life!  If so, that will certainly make the list in 2012!

The launch of the Mars Science Laboratory rover, called Curiosity.  Courtesy NASA.

The Uncookable Comet Lovejoy
A late entry - but an amazing one!  Kreutz sungrazer Comet Lovejoy was discovered by Australia's Terry Lovejoy a bit less than a month before its close encounter with the Sun.  No one expected the cosmic chunk of ice and rock to survive its passage a mere 87,000 miles above the solar surface (Earth is on average 93 million miles from the Sun and I can still get a sunburn in the winter!) on December 16.  But as I write this, Comet Lovejoy is still kicking, headed away from the Sun and sporting an enormous tail.  Sadly, we can't see it very well from here in the United States, but its discoverer is still getting a nice view!  Southern hemisphere dwellers - get outside before the sunrise and enjoy the view of Comet Lovejoy in the east.  It's well worth the effort!

Comet Lovejoy after its incredible solar encounter by Kosma Coronaios. Courtesy spaceweather.com

Pluto May Not Be a Planet...But it is a Moon Magnet!
First among dwarf planets Pluto was back in the news again this year - sporting a newly discovered moon.  The intrepid Hubble Space Telescope was searching for rings around the tiny body, but instead discovered a fourth moon circling this enigmatic little world.  Officially announced on July 20, 2011, little S/2011 P4 doesn't yet have a proper name.  But its discovery confirms that this world, though no longer considered a major planet, will remain a target for scientific curiosity and discovery for years to come.  New Horizons will arrive in 2015, increasing our understanding of the Plutonian system exponentially.  I can't wait!

The discovery of Pluto's newest moon, S2011/P4.  Courtesy STSci.

The End of an Era: NASA Retires the Space Shuttle
For 30 years, manned spaceflight was synonymous with the Space Shuttle.  NASA's fleet of launch-like-a-rocket-land-like-a-glider spacecraft were amazing machines, completing 135 missions to space, launching innumerable satellites and spacecraft, conducting thousands of experiments, and performing 37 construction and service visits to the International Space Station.  Groundbreaking mission like those of the Galileo spacecraft and the Hubble Space Telescope started with a launch from the cargo bay of a space shuttle.  While we mourn the loss of the 14 astronauts who died in the Challenger and Columbia tragedies, we must also acknowledge that the shuttle's work record of 30 years is nothing short of extraordinary.

Space Shuttle Discovery.  Courtesy NASA.

Now the United States has no manned spaceflight capability,. and the future of human exploration of space has never looked more bleak.  No other space agency has the same level of experience which NASA has in manned spaceflight.  But we will lose those skills rapidly if we can no longer send people into space to use them.  While NASA is actively seeking new astronauts, I wonder what they will do, since they must rely on the faltering Russian space agency to successfully carry them into space.  Human space exploration fires the imagination like few other things can, and the technological spinoffs from such efforts are too numerous to detail.  I hope that our government will be willing to make an investment in a future they can't imagine now, and not let the problems of today kill the dreams of tomorrow.

I wish you all a wonderful holiday season full of family, friends, love and joy.  And may 2012 be a truly stellar year for us all.
Carpe annum!
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