August 26 – Well, Blow Me Down

Today’s factismal: The “Year Without A Summer” was not caused by the eruption of Krakatoa.

Stop me if you’ve heard this one before – way back when, there was a massive volcanic eruption that was so loud it was heard in Australia and put so much ash into the air that everything froze and we had a year without a summer. Great story, right? The only problem is that it isn’t; instead, it is two great stories.

The eruption of Mt Saint Helens was actually fairly small as such things go (Image courtesy USGS)

The eruption of Mt Saint Helens was actually fairly small as such things go
(Image courtesy USGS)

The first story is actually the last one. Back in 1815, Mount Tambora in Sumbawa exploded in the largest volcanic eruption in recorded history. It turned 24 cubic miles of rock into dust and debris and was loud enough to be heard for 1,200 miles. The eruption alone killed some 11,000 people. Worse, all of that dust in the air dropped the global temperature by a full degree below which was enough to kill crops and cause starvation in many areas; experts estimate that this killed another 60,000 people. (For comparison, the global temperature is now nearly two degrees above average this is not a good thing, either.)

When Pinatubo erupted in 1991, it cooled the planet by about 0.25 °

When Pinatubo erupted in 1991, it cooled the planet by about 0.25°

The second story happened nearly 68 years later at a spot nearly 900 miles away. On August 26, 1883, Mount Krakatoa erupted violently. The eruption wasn’t a surprise as the mountain had been spewing “fire fountains” into the air for months. What was a surprise was the size of the eruption; experts think that the neck of the magma chamber had become plugged with debris. Like holding your thumb over the neck of a soda bottle while shaking it, that allowed the pressure to build until it finally spewed out. That would have been bad enough, but the eruption created a caldera that went down below sea level. As the ocean water rushed in, it created a phreatic (steam) explosion, resulting in a sound so loud it could be heard 2,600 miles away and a tsunami that devastated coastlines across the Pacific and killed some 36,000 people. Because this was a smaller explosion than Tambora, only a few cubic miles of dust were tossed into the stratosphere and the weather was only made chilly instead of cold. As a result, there wasn’t the mass starvation of the previous eruption.

Exciting as the two eruptions were and interesting as the volcanology is, there is another facet to the two events that has a far more practical effect on us today: their effect on the weather. Since modern meteorological systems weren’t in place during the two eruptions (heck, meteorology hadn’t even been invented when Tambora blew!), climatologists must search for clues to their effects using old ship’s logs and diaries. And that’s where you come in. At Old Weather, you can look through the logs of sailing ships to discover what the weather and other things were like. By highlighting those entries, you help the folks who are trying to figure out what our new weather will do next. To learn more, blow on over to:
https://www.oldweather.org/

August 24 – Tembling In Fear

Today’s factismal: An earthquake is called a temblor by the folks who study them.

The past 24 hours has been very interesting. In that time we’ve seen a Mb 6.8 earthquake in Burma, a Mb 6.2 temblor in Italy, and a Mb 6.0 event in Indonesia.

A comparison of the energy released by the big earthquakes we've had in the past day

A comparison of the energy released by the big earthquakes we’ve had in the past day

Though we still don’t know what the damage from these events will be, most experts expect it to be a few hundred dead in each case because the areas that were affected are mostly un-reinforced masonry buildings. that do not hold up well in an earthquake. Now, the typical lay reader is probably thinking “I should donate to the relief funds” and the typical lay reader would be right. Getting supplies and shelter to those in the disaster areas will definitely help more people survive. But the typical lay reader is probably also thinking “Gosh, three biggies in one day – there has to be something going on” and the typical lay reader would be wrong.

The past week's temblors (Image courtesy USGS)

The past days’s large temblors
(Image courtesy USGS)

The typical lay reader is wrong because there are earthquakes every day. Lots of them. On a typical day, there are about 4,000 earthquakes. Now most of those events are very small; they tend to be Mb 1 or Mb 2. But every year there are 134 or so events with a magnitude between 6 and 7. So on average we would expect to see an earthquake this large about once every three days. And since earthquakes happen at random, the odds of seeing three events in any given 24 hour period are not that bad – about 1 in 27. In other words, we should expect to have a replay of today’s events about once a month or so. Fortunately, most of the Earth is empty ocean so most of those replays take place far, far away from any people.

One year of earthquakes across the world. (Image courtesy the USGS)

One year of earthquakes across the world. (Image courtesy the USGS)

We get earthquakes because the Earth is hot inside. That heat creates motion in the mantle that geology wonks call convection. And the motion of the mantle drives motion of the Earth’s crust, breaking it into large rigid sections called plates. As the plates collide to form mountain ranges or scrape alongside in transform zones, they release energy as earthquakes. For Burma, the plates that are colliding are the India plate and the Eurasian plate and the mountains that are being built are the Himalayas. For Italy, the plates that are colliding are the Nubia plate and the European plate and the mountains that are being built are the Apennines. And for Indonesia, the plates that are colliding are the Australia plate and the India plate and the mountains that are being built are Indonesia. And though the temblors cause a lot of damage and deaths they also give us a chance to learn more about how to make the next one less dangerous.

The different layers of the Earth. Only the outer core is molten; everything else s solid!

The different layers of the Earth. Only the outer core is molten; everything else is solid!

You see, after each earthquake, people who felt it have gone to the Did You Feel It? page and told the USGS what they felt. That helped the geophysicists to determine which parts of the world are most susceptible to earthquake damage which tells  first responders where we need to improve building codes and emergency response.

The results of Did You Feel It? for the past decade (Image courtesy USGS)

The results of Did You Feel It? for the past decade
(Image courtesy USGS)

If you’d like to help, participating is easy. The next time you feel an earthquake, go over to Did You Feel It? and let them know what you felt. Then sit back and enjoy the knowledge that you’ve just helped make us all a little bit safer.

August 23 – Far Sighted

Today’s factismal: Galileo demonstrated the telescope to the public for the first time 407 years ago today.

It isn’t often that someone invents one device that literally changes the way we see the Universe; what is exceptional about Galileo is that he invented two devices that did it. In 1625, he invented a occhiolino (“little eye”) that allowed him to explore the world of the miniscule; at a dinner in his honor, one of his students gave the device the name that we now know it by: the microscope (“seer of little things”). But that wasn’t his first foray into optics, nor his most famous. For that invention, we need to step back to August 23, 1609, when Galileo revealed his telescope (“seer of distant things”).

Galileo's telescope revolutionized our view of the Universe - literally!

Galileo’s telescope revolutionized our view of the Universe – literally!

Though there were field glasses before Galileo, they had limited magnification and blurry images. Worse, the poor quality glass caused rainbow rings to show around everything. Galileo got around these problems by using several lenses in series to adjust the image bit by bit. This method is still used today in binoculars and other optical devices.

Jupiter and three of its moons, as seen through a modern camera (mine)

Jupiter and three of its moons, as seen through a modern camera (mine)

Once Galileo had invented his telescope, he turned it onto the sky and saw nothing but trouble. One of the first things he saw was Jupiter and four bright points of light that circled around it. By the end of the week, he had proven that these small starry messengers revolved around Jupiter. Being a savvy sort, he published his findings in Sidereus Nuncius, a short treatise that was dedicated to Cosimo II de’ Medici and called the four moons of Jupiter “Medicean stars”. We now know them as Europa, Ganymede, Callisto, and Io and call them the Galilean satellites.

Before Galileo, nobody knew that the Moon had craters (image from my camera)

Before Galileo, nobody knew that the Moon had craters (image from my camera)

His invention literally changed the way we see the universe, but his discovery did so figuratively. Under Aristotle’s view of the cosmos, the Earth was the center and everything revolved around it. Things in the heavens were perfect and pure, and were in heaven because they were pure and perfect. Because the ideology fit so well with the dogma of the Catholic Church, it was adopted as Church Law – to challenge it was to challenge the very essence of belief. Though some troubling differences had arisen between the pure circles demanded by Aristotle and the observed paths of the planets, these were smoothed over by Ptolemy’s “epicycles” of circles on circles. Questioning these ideas was dangerous at best and heresy at worst.

The Solar System as Copernicus saw it (and Galileo proved)

The Solar System as Copernicus saw it (and Galileo proved)

Galileo did worse than question them: he made it possible for anyone to see that he was right and the Church was wrong. By simply looking through the telescope, people could see everything that he discovered. They could see the moons of another planet. They could see the “jug-ears” of Saturn. They could see the phases of Venus. They could see the spots on the face of the Sun and the scars on the face of the Moon.

Galileo's sketch of Saturn

Galileo’s sketch of Saturn

Galileo was first rewarded for his discoveries and then punished for his hubris. He became a superstar in Pisa, and other city-states wooed him, trying to get him to move and to bring his beautiful ideas with him. But his ego led him to clash with others, making enemies out of supporters. Eventually, he was brought before the Inquisition for heresy and threatened with torture. He renounced his views and spent the rest of his life under house arrest. It would be 206 years before the Roman Catholic Church would take his works off of the banned list and 376 years before the Vatican would formally clear him of any wrongdoing.

Galileo's drawing of sunspots (Image courtesy The Galileo Project)

Galileo’s drawing of sunspots
(Image courtesy The Galileo Project)

In opening the heavens to us, Galileo laid the foundations of modern science. He showed that clear logic alone (Aristotle’s approach) is not enough. Logic must be backed with evidence and hypotheses must be checked against observations. If you would like to honor Galileo, there is no better way than in joining one of the citizen science groups that is classifying and naming features on the Moon!
http://lunarscience.nasa.gov/citizen-science/

August 16 – “Its A Major Award!”

Today’s factismal: Hugo Gernsback was born 132 years ago today.

If you are the average person, odds are you’ve never heard of Hugo Gernsback. Then again, if you are the average person, odds are that you aren’t reading this right now so why am I bothering to talk to you? Instead, let me talk to the people who are reading this – the u when hugnusual suspects who have a nagging feeling that they should know who that Gernsback guy is.

Back in 1884 when Hugo was born, radio was just getting started and Marconi and Tesla were still arguing over who invented it (Tesla did the heavy lifting but Marconi got most of the credit). At that time, most radios were simple affairs built by hand by home hobbyists. And little had changed in 1908 when Hugo created the magazine Modern Electrics. In every issue, he presented circuits and diagrams and helpful advice on building and maintaining your own radio. Now, even though there was a lot to say about radio and other electrics (the word electronics wouldn’t be invented for another four decades), every once in a while the magazine had some empty space to fill. So in April 1911 Hugo decided to fill some of that empty space between the pages (and in his reader’s heads) with a “fantasy” novel that he called Ralph 124C 41+. Hugo had invented the science fiction magazine.

His work was an immediate success and he kept the tradition alive in both Modern Electrics and The Electrical Experimenter until he finally created a magazine with nothing but those science fictions in it. He called the magazine Amazing Stories and coined the terms “science fiction” and “scientifiction” (his favorite) for the new genre. He also published the names and addresses of the folks who wrote in to his magazine. They then started corresponding directly with each other and so Hugo indirectly invented science fiction fandom.

In 1953, the 11th Annual World Con (a convention of science fiction fans and those that endure them) gave out awards for the best novel, best short story, and so forth. And in his honor, the awards were called Hugos. It is now 132 years after Hugo was born and 63 years after the Hugos were born and that time of year is upon us once more. So if you have the chance, head to the WorldCon at MidAmericaCon II in Kansas City, MO, and watch this year’s Hugos get awarded. Or just pick up one of his stories and enjoy. Either way, you’ll come out ahead.

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/

August 9 – The Dead Planet

Today’s factismal: Mars has more surface area than all seven continents combined.

If you hang around JPL or the Russian launch center at Baikonur for any length of time, you’ve probably heard them talking about the Great Galactic Ghoul. According to legend, this monster hides out near Mars and lives off of the space probes that it eats. And what a diet it has had! Over the past five decades, the Great Galactic Ghoul has eaten about half of the probes sent to Mars. For example, on August 9, 1973, the USSR sent Mars 7, one of four different probes to Mars that they would launch that summer.  All four probes would be eaten by the Great Galactic Ghoul.

Percival Lowell's drawing of the martian canals (Image courtesy Percival Lowell)

Percival Lowell’s drawing of the martian canals
(Image courtesy Percival Lowell)

Of course, nobody actually thinks that there is a giant space monster out there eating our probes. (Well, maybe a few politicians.) The Great Galactic Ghoul just symbolizes how difficult it is to send a probe to another planet. So why do we keep doing it? In a word: science. By sending rovers and landers and orbiters to Mars, we can learn a lot about the planet. For example, we’ve learned that Mars is not covered with canals, that Mars is covered with ground water, and that there might be life on Mars (in the form of bacteria living deep in the soil).

The little rover that could; Opportunity has lasted twwelve long years on Mars (take *that* Mark Whatney!) (Image courtesy NASA)

The little rover that could; Opportunity has lasted twelve long years on Mars (take *that* Mark Whatney!)
(Image courtesy NASA)

But Mars is a planet with more surface area to explore than all seven continents combined. Thus far we’ve explored that enormous area with seven landers and four rovers supplemented with ten orbiters. That’s like saying that we’ve explored Earth by driving half-way from Washington DC to New York City while stopping at the Chicago, Albuquerque, and Moscow airports. Needless to say, there’s a lot left to explore.

A dust devil on Mars as seen by Spirit (Image courtesy NASA)

A dust devil on Mars as seen by the Spirit rover
(Image courtesy NASA)

And that’s where you come in. It turns out that one of the most important parts of planning a mission for a lander or rover is deciding where it should land. And in order to that the scientists need to look at every image of Mars’ surface taken by the Mars Reconnaissance Orbiter (MRO for short). But there are a lot of images to sort through. The MRO has three cameras and has been in orbit for a decade now; all told, it has taken more than 250,000 pictures of Mars’ surface. So the scientists need ordinary folks (that’s you) to look through the backlog of pictures and help them decide what they are looking at. Is it sand dunes? Is it flat plains? It is valleys? Or mountains? To take part, head over to Planet Four – just mind the Great Galactic Ghoul!
https://www.planetfour.org/

 

August 5 – Comet Chameleon

Today’s factismal: The word comet means “long-haired”.

Back in the days of the ancient Romans, when a comet would appear in the sky it was always an evil omen; they considered it to be a “bad star” or disaster. Even though the comet signaled death, destruction, and the start of the primary season, the Romans and Greeks kept their sense of humor. Because the comet had two long tails streaming out like hair in a sea breeze, they called it “long haired” or komētēs.

Comet Lovejoy as seen from the ISS (Image courtesy Dan Burbank, NASA)

The two tails of Comet Lovejoy as seen from the ISS
(Image courtesy Dan Burbank, NASA)

Nowadays we don’t think of comets as being evil omens but we are still fascinated by the tails that they trail, starting with the number of tails – two.  A comet has two tails because it is made of two types of stuff. Thanks to spectroscopy, we know that the nucleus is mainly made up of ices (water ice, ammonia ice, and even methane and carbon dioxide ice) with pieces of dust for texture; this mixture of rock and ice is why comets are often called “dirty snowballs”.

The two tails of Hale-Bopp (Image courtesy NASA)

The two tails of Hale-Bopp
(Image courtesy NASA)

As the comet gets closer to the Sun the outermost ice heats up and spews out gasses that form a globe called the coma (which means “hair” – yep, those Greeks had a thing). 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.

Comet Hyakutake passes the Sun (Image from SoHo)

Comet Hyakutake passes the Sun (Image from SoHo)

The interesting thing about the tails is that they do more than expand. Thanks to all that heat from the Sun, they also glow. And scientists can use that glow to tell us what the comet is made of; things like amino acids and phosphorus – the building blocks of life. Scientists have been doing this for an amazingly long time; on August 5, 1864, Giovanni Batista Donati did the first spectroscopic analysis of a comet and discovered that they had carbon in them. The other interesting thing about comet tails is that they can help us know where the comet formed. Because different things turn solid at different temperatures, by looking for these things in a comet’s tail, we can learn how far away from the Sun it was when it was born. But in order to do that, we need more information on comets.

Comet Sealy in the Texas night sky (My camera)

Comet ISON in the Texas night sky
(My camera)

And that’s where you come in. Comet Hunters is looking for comets that have become trapped in the asteroid belt by Jupiter. If you look through the images from Hawai’is Subaru telescope on Mauna Kea, you might spot one hiding in among the rocks. To learn more (and chase some tails), head over to:
https://www.zooniverse.org/projects/mschwamb/comet-hunters