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:

August 3 – Its A Gasser

Today’s factismal: John Tyndall was born 196 years ago today.

Ever since there have been toddlers, there’s been the question “Why is the sky blue?” And ever since John Tyndall, we’ve known the answer to that question. Born in Ireland to a family of moderate means, he was originally trained to be a surveyor. The mathematics of the job fascinated him, and he soon forsook the physical labor of surveying for the hallowed halls of the University of Marburg, where he studied under such luminaries as Robert Bunsen (of burner fame) and Gustav Magnus (of curveball fame). He soon graduated and went to work researching magnetism.

John Tyndall (Image courtesy Tyndall Institute)

John Tyndall
(Image courtesy Tyndall Institute)

At the time, light was just starting to be recognized as an electromagnetic phenomenon and it was a natural transition for him to start investigating the effects of “radiant energy” (the energy carried by light). Among his first experiments was a series of tests on nitrogen, oxygen, and carbon dioxide, looking to see how they would react to radiant energy. He thus performed the first experiment demonstrating what would come to be known as the greenhouse effect; as the concentration of carbon dioxide in the air increases, the temperature rises. His work was well-received and duplicated across the globe almost immediately after its publication in 1859, and led directly to the first prediction of how the Earth’s temperature would change as the CO2 increased.

Shortly after that, Tyndall became fascinated by the way that particles suspended in the air would scatter the light and change the color. He discovered that smoke (like that from a pipe or a coal stove) would appear slightly blue, and that the more particles there were in the smoke (i.e., the less complete the burning was), the bluer it seemed. He realized that the light was being bounced in all directions by the particles and that blue light was able to pass through more easily because it had the longer wavelength; in effect, it bounced off of fewer particles and so was less likely to be absorbed.

The mountain haze appears blue thanks to the Tyndall effect (My camera)

The mountain haze appears blue thanks to the Tyndall effect
(My camera)

Though many thought (and some still do) that he had answered the question of “Why is the sky blue?”, it turned out that he hadn’t. But what he had done was point the way toward the real answer, which was found just a few years later. (His answer was wrong because the particles in smoke are too big to scatter enough light to make the sky blue.) But he was happy to have helped move us closer to the answer.

And that’s what citizen scientists do. By collecting data, they help other researchers get a little closer to the day when we’ll be able to answer all of those other questions that a three year-old asks. Questions like “Why are there clouds?” (It turns out that is a harder question to answer than you might think.) If you’d like to help, then why not go back to S’COOL (Students’ Cloud Observations On-Line) Roving Observer?

August 1 – A Real Shot In The Arm

Today’s factismal: August is National Immunization Awareness Month.

The smallpox virus (Image courtesy CDC)

The smallpox virus, former public enemy number one
(Image courtesy CDC)

If you want to be thankful for modern medicine, all you have to do is look at what used to kill us. In 1900, influenza was the leading cause of death in the USA (153,000 deaths or 202/100,000); today, it is the ninth most common (50,097 or 16/100,000). In 1964-1965, there were 20,000 babies born with congenital rubella syndrome in the USA; in the past ten years, there were none, thanks to vaccines. In 1916 in the US alone, there were more than 27,000 new cases of polio that paralyzed thousands and killed 6,000 people; in 2012 for the entire world, there were just 223 new cases of polio and no deaths or paralyzations. And then there is the best example for why we vaccinate – smallpox. In 1967, 2,000,000 people were killed each year by smallpox and countless others were left scarred or blind; today, nobody dies of smallpox thanks to an effective vaccination campaign.

Vaccines contain trivial amounts of antiseptics (Data courtesy CDC)

Vaccines contain trivial amounts of antiseptics
(Data courtesy CDC)

Unfortunately, a lot of people have forgotten how dangerous things used to be and are no longer vaccinating their children. They are worried by vaccine ingredients such as aluminum potassium sulfate (the stuff that makes pickles taste sour), agar (the stuff that makes toothpaste a paste), formaldehyde (made by your body as part of the energy cycle), and dihydrogen monoxide (water). Even though the ingredients are tested and known to be safe, scaremongering news stories have led many to stop vaccinating. And that’s a bad thing.

A simplified view of herd immunity

A simplified view of herd immunity

It is bad because vaccines do more than protect the people who take them; they also protect the people who can’t. People such as newborn infants (like the ones who were infected with measles by a missionary returning from overseas), people with compromised immune systems (such as children with cancer), and people for whom the vaccine never took (estimated to be about 5% of the population). By getting vaccinated, we create a “ring of immunity” that keeps the disease from spreading as quickly as it otherwise would (the Disneyland outbreak is a good example of herd immunity at work). And, of course, if enough people use the vaccine, then the disease is eradicated which means that we can stop using the vaccine!

A comparison of the deaths caused by measles and those caused by vaccines; the vaccine deaths were exaggerated for clarity. Each face represents 1,000 deaths.

A comparison of the deaths caused by measles and those caused by vaccines; the vaccine deaths were exaggerated for clarity. Each face represents 1,000 deaths.

Now it is true that vaccines are not perfectly safe. An estimated 10,000 people have died from vaccines. But it is also true that getting vaccinated is much, much, much safer than not doing so. Let’s take the flu for example. The flu vaccine reduces the chances of getting the flu by nearly 70% (that is, if 1,000,000 people who took the vaccine would have gotten the flu then only 300,000 actually do); experts estimate that the flu vaccine has saved at least 40,000 people’s lives. Similarly, the polio vaccine prevents two million cases each year which would kill nearly 500,000 people and leave another 750,000 paralyzed.

So what can you do for National Immunization Awareness Month? First, take care of yourself and your family by making sure that everyone’s vaccinations are up to date. Then take care of others by working with Global Vaccines. They are using their profits from vaccines in countries like the USA to pay for vaccinations in poor countries:

If you’d like to help drive a disease into extinction, then join the Global Polio Eradication Initiative:

And remember that flu season is just around the corner. Flu vaccines are safe, effective, and free under most health plans!


July 29 – Cold, Cruel Fate

Today’s factismal: Eris “the Pluto killer” was discovered eleven years ago.

One of the most contentious questions in science today is “What is a planet?” Scientists can (and do) argue over the question for hours at a time, mainly because how you answer it all depends on what characteristics you think are important for planets. Most notably, the International Astronomical Union (a body that was set up to keep us from arguing over names) famously decided that not only was Pluto not a planet, it wasn’t even related to “real” planets. Interestingly, they did this even though their own subcommittee said that Pluto should remain a planet and even though many planetologists consider Pluto to be one.

The Eris system (Image courtesy NASA)

The Eris system
(Image courtesy NASA)

But why was Pluto “killed”? Why did they decide that Pluto wasn’t a planet? It all starts with Pluto itself. When it was found, Pluto was so far away that it was just a dim light in the telescope. As a result, everything that we thought about Pluto was based on the other planets that were out there: Jupiter, Saturn, Uranus, and Neptune. All of those planets are big and gaseous (what planetologists call “jovian planets”), so the natural assumption was that Pluto was more of the same. But as telescopes got better, Pluto got smaller. It shrank from being the size of Jupiter to being the size of the Earth to being smaller than the Moon (for what it is worth, the planet Mercury is only a little larger than the Moon).

Pluto and its largest moon, Charon (Image courtesy NASA)

Pluto and its largest moon, Charon
(Image courtesy NASA)

And, as if that weren’t bad enough, we started seeing other objects out near Pluto that were about the same size as the planet itself. The most famous of these new planets was Eris, aptly named for the Greek goddess of discord, which was actually larger than Pluto. The astronomers then panicked over the prospect of having more than ten planets in the Solar System and led the IAU to redefine the word so that they wouldn’t have to quit using their fingers to count. (To be fair, this wasn’t the first time that the problem had arisen; it happened with the Galilean planets and with the minor planets.) As a result, Pluto and the other planets out there became known as “dwarf planets” (an appellation that was originally intended to apply to Earth).

A plot of planetary size versus density. Notice how Pluto ends up with the junk.

A plot of planetary size versus density. Notice how Pluto ends up with the junk.

But call it a dwarf planet, a KBO, or a giant cookie, Pluto is still out there.Even better, there are thousands upon thousands upon thousands of other planets out there, just waiting to be found! If you’d like to try your hand at discovering the next planet of discord, then why not head over to Planet Hunters? They’ve got tons of Kepler data just waiting for you!

July 27 – We’re Off To See The Lizard

Today’s factismal: Reptiles are found on every continent except Antarctica (and they used to live there!).

If you want to call a group of animals successful, then you have your choice of how to define the term. You can base it on the distribution of the critters: those that live in more places are more successful. Or you can base it on the longevity of the critters’ family tree (what biology wonks call a clade): those that have been around longer are more successful. Or you can base it on all of the other critters that have evolved out of that clade: having more branches on their tree of life makes them more successful.

An alligator in Texas (My camera)

An alligator in Texas
(My camera)

But no matter how you define success, the reptiles have it. They’re found on every continent except Antarctica (they moved away from there when it got too cold), they’ve been around for 312 million years, and their descendants include obvious suspects like crocodiles and turtles, and some not-so-obvious ones like the dinosaurs, the birds, and the mammals.

An iguana in Florida (My camera)

An iguana in Florida
(My camera)

But success has its price. In the case of the reptiles, it means getting pushed out by younger and more vigorous critters, like humans. In Los Angeles and other parts of California, the native lizards have almost entirely disappeared, thanks to changes in the environment caused by building and water use. It has gotten so bad that now researchers are out looking for lizards, and they’d like your help. If you happen to live in Los Angeles (or are just stuck in a tourist trap ☺), then why not give them a hand by reporting any lizards that you see to the RASCals Project at the Los Angeles Natural History Museum:

July 25 – Last Leg To Stand On

Today’s factismal: The Solar Impulse II is on its last leg of an around-the-world flight.

All too often we forget that the future is happening now but it started long ago. For one example of that, I point you to the Solar Impulse II. This amazing aircraft is designed to take off, fly, and land using nothing but the solar power it harvests with the solar cells on its wings. Though it will never be able to carry anything other than two pilots and a very minimal cargo, the airplane will demonstrate that we have only begun to tap into what can be accomplished.

And what can be accomplished? Lots! Right now, the solar powered airplane is on the last leg of its around-the-world flight that started on March 9, 2015. It has already set several records, including longest flight by a solar-powered airplane (4,819 nmi from Japan to Hawai’i) and the longest non-stop solo flight without refueling (Japan to Hawai’i again). More importantly, it has shown that we can do a lot more with solar power and other alternative energy sources. When it touches down in Abu Dhabi next month, this plane will become the first solar powered plane to circumnavigate the globe.

The Solar Impulse in flight (Image courtesy Solar Impulse)

The HB-SIA in flight
(Image courtesy Solar Impulse)

But where and when did this airplane start? (Other than last March in Abu Dhabi.) Perhaps we should point our fingers at Elmer Johnson, who was awarded US patent 3,089,670 for a solar-powered aircraft on May 14, 1963. But Elmer points his finger at others (including one gentleman who wanted to build a solar-powered flying saucer). And, if we follow the line of patents far enough back, we’ll find ourselves looking at a certain patent clerk by the name of Albert Einstein who first deduced how solar power cells work back in 1915.

If you’d like to spend some time looking forward, then why not check out the Solar Impulse?

July 22 – Too Darn Cold

Today’s factismal: The lowest recorded naturally occurring temperature on Earth was 128.6 °F below zero; it happened at Vostok Station in Antarctica in 1983.

Right now, most of North America is in the grip of a record-setting heat wave. Forget frying eggs on the sidewalk; right now, the chickens are laying the eggs already fried. (Then again, they do that all the time in Colorado.) And odds are you’re thinking about a trip to someplace cool. In that case, may I suggest lovely Lake Vostok?

A cross section of the ice above Lake Vostok and a map showing where the Pole of Cold is (Image courtesy Nicolle Rager-Fuller / NSF)

A cross section of the ice above Lake Vostok and a map showing where the Pole of Cold is
(Image courtesy Nicolle Rager-Fuller / NSF)

Located in Antarctica’s “Pole of Cold” (yep, there’s a pole for everything), Lake Vostok is home to a research station located on the thick ice on top of the lake. How thick is the ice? Let’s put it this way: the research station sits on the ice more than two miles above sea level but the lake’s surface is 1/3 of a mile below sea level. All of that ice is there for a reason. Because Vostok Station is located in the middle of Antarctica, cold temperatures are just a fact of life. And those cold temperatures allow ice to build and build and build over hundreds of thousands of years; the ice over Lake Vostok represents more than 400,000 years of snowfall and gives climatologists an incredibly detailed look into the past. Of course, that assumes that they can survive the present.  In 1983, Vostok Station in Antarctica recorded an air temperature of 128.6 °F below zero.

The monthly average high and low temperatures for Vostok Station, Antarctica (Brr!)

The monthly average high and low temperatures for Vostok Station, Antarctica (Brr!)

Exciting as all of that ice is (think of the snow cones!), it is actually the least interesting thing about Lake Vostok. The most interesting thins is that all of that ice has sealed off the lake for some 15 million years, which means that it is possible that it is host to fish and other critters that have evolved separately from those everywhere else or (and here’s the exciting part) it may have completely new critters that will tell us if we might find life elsewhere in the Solar System.

The two sides of Europa, one of Jupiter's ice-covered moons (Image courtesy NASA)

The two sides of Europa, one of Jupiter’s ice-covered moons that may have life like that at the bottom of Lake Vostok
(Image courtesy NASA)

About three years ago, scientists did manage to drill into the lake and a second drill hole was completed last year. There have been some indications that they did discover lots and lots of critters but the question of how new they are is still undecided. (Read: lots of biologists are arguing about it.) What is known for sure is that it is amazing that anything could actually live in a lake that is in perpetual darkness, under a pressure equal to 350 atmospheres, and is so full of oxygen and nitrogen that the water would bubble if it were brought to the surface. And the other thing that is known for sure is that once the critters from Lake Vostok are identified, they’ll make their way into the Encyclopedia of Life. It is a free on-line resource that lists every known animal, plant, protist, or politician (wait; I’ve just been informed that politicians are not considered to be life forms). If you’d like to check it out, look here: