February 6 – The Sky’s A Rockin’!

Today’s factismal: Nearly 42,000 meteorites hit the Earth every year.

Odds are, you’ve seen the really cool dashboard video of the meteor that light up the sky in Illinois and Wisconsin last night. Right now, we don’t know much about this particular meteor other than it was big and bright. We don’t know if it landed somewhere on Earth like the 42,000 other meteorites than come to ground each year or if it headed back out into space like the The Great Daylight Fireball of 1972. We’re not even sure where it came from – was it a piece of a comet or a chunk of an asteroid?

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

What we do know is that there will be nearly 70 different chunks of rock and ice that speed by the Earth in February alone! They’ll zoom past at distances ranging from just outside the atmosphere to 78 times the distance to the Moon. They range in size from the size of a tiny house (about 36 ft) to the size of a tiny village (about a mile across). These rocks are made up of chunks of comets and asteroids and even bits of Mars and the Moon that have been blasted into space by impacts from other chunks of rock!

A meteor streak across the Milky Way (My camera)

A meteor streak across the Milky Way
(My camera)

What is important about these chunks of rock is that they tell us how dynamic our Solar System is. Instead of being a dead old system with an orbit for everything and everything in its orbit, the Solar System is a dynamic, ever-changing system with the planets and comets and asteroids interacting to change orbits and thrown new stuff in new places. And they can provide us with samples from other planets and from the earliest formation of the system. Besides which, they are just plain pretty!

A meteorite as seen from above the atmosphere  (Image courtesy NASA/Ron Garan)

A meteorite as seen from above the atmosphere
(Image courtesy NASA/Ron Garan)

But the best thing about meteor is that you can help scientists learn more about them! If you download NASA’s Meteor Counter App (available for iPad, iPhone, and iWannaMeteor), then you’ll be able to send NASA scientists valuable information on the number of meteors that hit during the shower. They’ll then use that information to help us understand how likely it is that we’ll get hit. To learn more, go to NASA’s web site:
http://science.nasa.gov/science-news/science-at-nasa/2011/13dec_meteorcounter/

December 31 – Hairy Situation

Today’s factismal: The New Year will start with not one but two comets!

There is something special about comets in the sky. These “long haired” wanderers do more than just provide a spectacular light show; they also create meteor showers and change the way we think about the world. And for the next couple of weeks there will be not one but two comets visible in the sky!

The first one is a regular visitor. Called Comet 45P/Honda-Mrkos-Pajdušáková (after the three people who discovered it), it is a member of the “Jupiter family” of comets. These are short-period comets that cycle between rushing by the Sun before heading back out toward Jupiter to cool their heels for a bit. 45P has a period of about five years; the last time it fly by the Sun was in 2011 and the next time will be in 2022.  And it will come relatively near Earth on February 11, 2017 – it will be just about eight million miles away! (If that sounds too close, remember that the Moon is about thirty times closer.) If you can’t wait, go out just before dawn and look to the East with binoculars. That faint, fuzzy patch? That’s the comet. It will get bigger and brighter over the next few weeks so you’ll have plenty of opportunities to see it.

Comet 45P as it flies from Jupiter's orbit in toward the Sun and back (Image courtesy NASA)

Comet 45P as it flies from Jupiter’s orbit in toward the Sun and back
(Image courtesy NASA)

But that’s not the only comet we can see tonight! There is also comet C/2016 U1 NEOWISE which was discovered by NASA’s NEOWISE project. Using images from the WISE space telescope, which spent a year surveying the sky in infrared, the folks at JPL have identified this long-period comet. Instead of just sprinting between Jupiter and the Sun, these comets run all the way from out past Pluto; as a result, their journeys can take tens of thousands of years. Right now, we aren’t sure how long this particular comet takes to complete an orbit or even if it will be ejected from the Solar System. What we do know is that it has already passed its closest approach to Earth and is heading in toward the Sun. As it gets closer, it will get brighter and may be visible to the naked eye early in the morning between now and January 14th when it passes the Sun and heads back out again.

A timelapse photo from SOHO showing what happens to a comet as it goes around the Sun (Image courtesy ESA)

A time lapse photo from SOHO showing what happens to a comet as it goes around the Sun
(Image courtesy ESA)

As comets get closer to the Sun the outermost ice heats up and spews out gasses that form a globe called the coma (which means “hair”). The gasses in the coma then become ionized and get dragged out by the solar wind forming the long glowing tail that is characteristic of comets; this gas tail always points straight away from the Sun. Little flakes of rock dust can also be lost. Because the dust is denser than the gas and isn’t ionized, it can form a second tail that curves away from the comet. (So straight tail=gas, curvy tail=dust. Now go impress your friends.) That dust is left behind in orbits that sometimes lead it to fall on Earth as fireballs.

The surface of a comet as seen by ESA's Rosetta probe (Image courtesy ESA)

The surface of a comet as seen by ESA’s Rosetta probe
(Image courtesy ESA)

And you can see the show using a pair of good, inexpensive binoculars. Binoculars are preferred by new astronomers because they gather a lot of light, which helps you see faint things, and because they give enough magnification, so you can see things like the moons of Jupiter, and because they are inexpensive (about $50). Or, if you’d like to spend about $1,000,000,000 you could launch another Solar and Heliospheric Observatory or SOHO for short.

This satellite, which was launched in 1995 and is still active today, was intended to observe the Sun and tell us more about how solar flares and coronal mass ejections affect life on Earth. But what NASA hadn’t expected when they launched SoHo was that they would see comets. But it turned out that SoHo saw a lot of comets that came to be called “Sun-grazers” for their death-defying feat of diving in near the Sun before heading back out into the dark depths of the outer Solar System.

Sometimes the stress of passing near the Sun or a planet causes a comet to break into pieces (Image courtesy ESA)

Sometimes the stress of passing near the Sun or a planet causes a comet to break into pieces
(Image courtesy ESA)

SoHo is still in orbit today, looking at the Sun and looking for comets. If you’d like to join the folks that have found more than 2,400 comets using SoHo images, then head on over to Sungrazing Comets:
http://sungrazer.nrl.navy.mil/index.php?p=guide

 

 

 

December 12 – Catch The Wave

Today’s factismal: You can see meteor tracks using radio waves.

If you are a radio history buff, today is a triple jackpot. It starts at the dawn of radio, back in 1896, when Marconi showed a rapt audience in East London how pressing a key could transmit a signal without wires. While his assistant carried a small battery-powered box around the room, showing that it was not connected by wires to anything, Marconi repeatedly pressed a telegraph key to trigger a spark-gap transmitter similar to the one that Tesla had invented just a few years earlier. That would create a signal that would then cause a bell to ring in the box. Wireless telegraphy (as it was called) had arrived.

Marconi would continue to work on wireless telegraphy even as Tesla abandoned it to work on inventing the rest of the modern world. And in just five years, Marconi had built a radio powerful enough to send a signal from Cornwall to New Foundland; on December 12, 1901, he became the first person to send a transatlantic radio message. Of course, given the primitive nature of the equipment, it wasn’t much of a signal – just the Morse code signal for “S” (dot-dot-dot) repeated over and over. Nevertheless, it spurred enough interest in his company that Marconi soon became rich and wireless telegraphy became commonplace.

Sixty years later, radio would make the news one more time as NASA launched the first privately constructed satellite in the world. On December 12, 1961, the OSCAR-1 (Orbiting Satellite Carrying Amateur Radio) hitch-hiked into orbit as a passenger on a military satellite launch. OSCAR-1 was designed and built by students at Foothill College in Los Altos Hills, California, with the help of the TRW Radio Club. The satellite worked flawlessly even though it had been built less than four years after Sputnik and was the world’s first piggy-pack satellite launch as well as the world’s first privately built satellite. For 22 days, OSCAR-1 circled the globe, streaming out a constant “HI HI” to everyone who tuned in.

The OSCAR-1 satellite (Image courtesy Smithsonian)

The OSCAR-1 satellite
(Image courtesy Smithsonian)

Today the OSCAR program continues to excite and inspire. And citizen scientists like Marconi and the students who built OSCAR-1 continue to help make new discoveries in science. For example, did you know that meteors sometimes reflect radio waves when they fall? Thanks to the pressure of their fall, they create a wake of ionized plasma; by bouncing radio waves off of the ionized air, we can learn how many meteorites fall and how they move. To get involved in tracking meteors, scream over to:
https://www.zooniverse.org/projects/zooniverse/radio-meteor-zoo

October 27 – Close Encounters Of The Worst Kind

Today’s factismal: Earth had at least 44 close encounters with an asteroid in this month alone!

It is, no fooling, a dangerous universe out there. There are gamma ray bursts and black holes and even some strange life forms out there. But perhaps the most amazing thing about the universe is how many close encounters the Earth has considering that space is mostly empty space. In the last month alone, NASA has recorded some 27 things that passed near enough to our orbit to be interesting (without the “Oh God, Oh God, we’re all going to die” part). NASA prefers to call these things “objects” because while most of them are just hunks of space rock heading for a fatal collision, some of them are actually bits of space junk headed back home.

A meteor enters the Earth's atmosphere, as seen from the ISS (Image courtesy NASA)

A meteor enters the Earth’s atmosphere, as seen from the ISS
(Image courtesy NASA)

And, of course, if we expand our definition of “asteroid” to include the bits of rock and dust and ice left in a comet’s wake, then there have been literally millions of “close encounters of the worst kind” in the past month. That’s because every day, more than 80,000 pounds of space debris hit the Earth’s atmosphere! If you look up at night, you’ll see those bits of rock and ice and dust; we call them meteors or shooting stars; if they are very big and very bright, then we call them “fireballs”.

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

Now those bits of debris are more than just pretty; they also tell us a lot about how the Solar System and the Earth formed. by keeping track of where they come from and how many there are, scientists can answer questions such as “Where are the comets?” and “How many asteroids hit the Earth?” and “Did an impact really kill off the dinosaurs?” But scientists can’t spend all of their time looking up at the sky; they’ve got data to work on and papers to write and blinking to do. So what are they to do?

Why, they’ll just ask for help. And that means asking you to spend some time looking at the sky each night. If you see a meteor, then just click on the NASA Meteor Counter app; the data you create will automatically be sent to NASA to help in their work! The app is available for free on iTunes and Google Play:
http://science.nasa.gov/science-news/science-at-nasa/2011/13dec_meteorcounter/

August 11 – Pretty But Deadly

Today’s factismal: Meteor showers are named after the constellation that they appear to come from.

If you go outside tonight or tomorrow night, you’ll be treated to not one but two astronomical amazements. The first is the sight of the Saturn and Mars lying less than a hand’s breath away from the Moon in the sky; if you go out just after sunset you’ll also be able to see Jupiter, Mercury, and Venus down low in the west. And beautiful as that set of planets is, it won’t be the most amazingly beautiful thing in the sky. That’s because tonight and tomorrow are the peak of the annual Perseid meteor shower.

Tonight's astronomical wonder (Image courtesy NASA)

One of tonight’s astronomical wonders
(Image courtesy NASA)

The Perseids happen when the Earth crosses the path of the comet Swift-Tuttle every year. Like a car getting hit by gravel flung off of the truck ahead, the Earth runs into the bits of dust and rock thrown off by Swift-Tuttle on its 130 year long journey around the Sun. The comet last passed by the Earth in 1992 (we’ll see it again in 2026) and left lots and lots of junk on our cosmic road. When that a piece of that junk hits the windscreen that is the Earth’s atmosphere, it heats up and forms the long, glowing trail that we call a “shooting star”. Thanks to the recent close encounter, we expect to see up to 200 meteors each hour in darker places. But even if you live in the city, you can expect to see some of the brighter meteors.

A meteor shower radiating (Image courtesy NASA)

A meteor shower “radiating”
(Image courtesy NASA)

To catch the light show, just go outside and look up. If you’d like a better chance at catching the falling stars, turn to the northeast at about 10 PM. Using your fist at arm’s length, count up two fists. That puts you right in the middle of the constellation of Perseus; if you hit the “W” of Cassiopeia, you are too high. And now just watch. The meteors will appear to radiate out of the center of Perseus which is why they are called the  Perseids.

Where to look tonight and tomorrow night (Image courtesy NASA)

Where to look tonight and tomorrow night
(Image courtesy NASA)

And meteors are more than just pretty; they can tell us a lot about comets and planets. And you can help! If you download NASA’s Meteor Counter App (available for iPad, iPhone, and iWannaMeteor), then you’ll be able to send NASA scientists valuable information on the number of meteors that hit during the shower. They’ll then use that information to help us understand how likely it is that we’ll get hit. To learn more, go to NASA’s web site:
http://science.nasa.gov/science-news/science-at-nasa/2011/13dec_meteorcounter/

November 6 – No Bull

Today’s factismal: The Taurid meteor shower looks like it is coming from Taurus the bull.

One of the cool things about the Earth is how often it gets hit by a meteorite. On average, 42,000 meteorites hit the Earth every year. That works out to be about 150 strikes each day! But some days are more average than others, and we are having a few of those days right now because we are in the middle of the Taurid meteor shower.

Named for Taurus the bull, which is the constellation just to the right of Orion as you look at it in the sky, this meteor shower happens when the Earth’s orbit takes it through the debris of comet Encke. As comets move closer to the Sun, they heat up and begin to outgas (which means just what it sounds like: they start to give off gas in noxious clouds {like Uncle Joe} and in large jets {like Aunt Sally}). The outgassing also breaks off small chunks of the comet which form a giant debris trail in the sky. Most of these chunks are about the size of a grain of sand, but some can be much larger. When the debris from the comet meets the Earth’s atmosphere, they create the meteor.

These eight images show how much gas is jetted off of a comet in just half an hour! (Image courtesy NASA)

These eight images show how much gas is jetted off of a comet in just half an hour!
(Image courtesy NASA)

Encke is pretty famous in astronomical circles; it was the second periodic comet every discovered (after Halley’s comet). A large reason for it being discovered was the fact that it has a very short period – just 3.3 years! Thanks to that short period, Encke has been shedding tons of dust and rocks into space. And thanks to that shrot period, we are fairly sure that Encke itself is the remains of a larger comet that broke apart some 20,000 years ago. Because it is so new, Encke has created one of the largest and broadest swaths of cosmic debris in the Solar system. Instead of lasting for a few days, the Taurid meteor shower typically lasts for a month!

The best place to watch a meteor shower, ever! (Image courtesy NASA)

The best place to watch a meteor shower, ever!
(Image courtesy NASA)

And if you’d like to do more than just ooh and aah at the pretty meteor as they burn up, why not download NASA’s Meteor Counter App (available for iPad, iPhone, and iWannaMeteor)? You’ll be able to send NASA scientists valuable information on the number of meteors that hit during the shower. To get the app, go to the iTunes store:
https://itunes.apple.com/us/app/meteor-counter/id466896415

October 30 – The Unparalleled Adventure of One Hans Pfaall

Today’s factismal: Earth had at least 27 close encounters with an asteroid in this month alone!

It is, no fooling, a dangerous universe out there. There are gamma ray bursts and black holes and even some strange life forms out there. But perhaps the most amazing thing about the universe is how many close encounters the Earth has considering that space is mostly empty space. In the last month alone, NASA has recorded some 27 things that passed near enough to our orbit to be interesting (without the “Oh God, Oh God, we’re all going to die” part). NASA prefers to call these things “objects” because while most of them are just hunks of space rock heading for a fatal collision, some of them are actually bits of space junk headed back home.

A meteor enters the Earth's atmosphere, as seen from the ISS (Image courtesy NASA)

A meteor enters the Earth’s atmosphere, as seen from the ISS
(Image courtesy NASA)

And, of course, if we expand our definition of “asteroid” to include the bits of rock and dust and ice left in a comet’s wake, then there have been literally millions of “close encounters of the worst kind” in the past month. That’s because every day, more than 80,000 pounds of space debris hit the Earth’s atmosphere! If you look up at night, you’ll see those bits of rock and ice and dust; we call them meteors or shooting stars; if they are very big and very bright, then we call them “fireballs”.

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

The Great Daylight Fireball of 1972 (Image courtesy and copyright James M. Baker)

Now those bits of debris are more than just pretty; they also tell us a lot about how the Solar System and the Earth formed. by keeping track of where they come from and how many there are, scientists can answer questions such as “Where are the comets?” and “How many asteroids hit the Earth?” and “Did an impact really kill off the dinosaurs?” But scientists can’t spend all of their time looking up at the sky; they’ve got data to work on and papers to write and blinking to do. So what are they to do?

Why, they’ll just ask for help. And that means asking you to spend some time looking at the sky each night. If you see a meteor, then just click on the NASA Meteor Counter app; the data you create will automatically be sent to NASA to help in their work! The app is available for free on iTunes and Google Play:
http://science.nasa.gov/science-news/science-at-nasa/2011/13dec_meteorcounter/