January 25 – Hot Topic, Cool Science

Factismal: IRAS was launched on January 25, 1983.

Astronomy entered a new age in 1983, with the launch of the Infrared Astronomy Satellite, or IRAS for short. IRAS wasn’t the first telescope into space, nor was it the first infrared telescope. But it was the first infrared telescope in space. And that is what matters, because it turns out that space is the place to be if you want to see something that is invisible.

The InfraRed Astronomical Satellite (IRAS) discovered the first exoplanet (Image courtesy NASA)

The InfraRed Astronomical Satellite (IRAS) discovered the first exoplanet (Image courtesy NASA)

You see, the part of the spectrum that we see is just a very, very limited part of a much wider whole. The visible spectrum, which covers the colors from blue through red, says a lot about the world. But the invisible spectrum, which covers colors that are cooler than red (the infrared) and hotter than blue (the ultraviolet), tells us a lot more about the universe. Part of that is simply because most of the universe is very, very cool. And the rest is because the parts that aren’t cool can be very hot indeed.

The hotter something is, the

The hotter something is, the “blue-er” its color is

And it turns out that the temperature is the key to the color. Back in 1900, Planck was able to show that the color of an object was intrinsically related to its color. For example, the Sun is yellow because the part of it that we see is about 5000 K (about 8540 F, or “really, really hot”). We now use that principle in a number of ways, from taking the temperature of a star to taking the temperature of a baby.

But not all colors of light make it through to the ground. To understand this, think of a brick wall. You cannot see through a brick wall because the bricks block the visible light while allowing more energetic gamma rays to pass through. Similarly, our atmosphere blocks a substantial part of the infrared light while letting the more energetic visible light through. And, just as you can see what’s on the other side of a brick wall by walking around it, telescopes can see the infrared colors blocked out by our atmosphere by going above it.

And when they did, what an amazing array of interesting things they saw. While looking at over 500,000 light sources, IRAS discovered the source of the Geminid meteor shower. IRAS discovered six new comets. IRAS saw the dust created by asteroid collisions as a giant cloud surrounding the Solar System. And IRAS saw 75,000 different galaxies with huge numbers of new stars being born. Most importantly, IRAS gave us the first picture of planets forming from a cosmic cloud of dust and gas.

And the hits from IRAS keep coming, even though the satellite quit working nearly thirty years ago. That’s because there are lots and lots of images from IRAS and other space telescopes that need people to look through them. People just like you! If you’d like to try your hand at classifying infrared images, then try the Milk Way Project:

January 23 – Up A Tree

Today’s factismal: The common tree squirrel can rotate its back ankles 180° in order to climb down a tree head-first.

Squirrels are fun, frolicsome, and fascinating critters. They jump from limb to limb in search of nuts and acorns that they bury in profusion and they crawl on the forest floor hoping to find some tasty insects, slugs, and small birds, or snakes.Because they move from climbing up to climbing down to crawling around with such frequency, they have developed some special adaptations. Perhaps the most interesting of these is their back ankles which rotate 180°; in effect, they can put their feet on backward. Though that would make them a little awkward if they did it on the ground, it is perfect for when they want to head down a tree head-first.

Unlike many other animals, squirrels don't hibernate in the winter (My camera)

Unlike many other animals, squirrels don’t hibernate in the winter
(My camera)

But why would a squirrel want to go head-first down a tree? Because squirrels have a lot of things that like to feast on them. By going down head-first, they can keep an eye out for snakes, birds, raccoons, and automobiles to name but three. Automobiles are particularly deadly; the jerky, back and forth evasion pattern that gray squirrels have evolved to escape from predators in a forest makes it very hard to automobile drivers to avoid hitting the poor beast. As a result, the leading cause of death for gray squirrels in a city is being run over.


Despite their predator problems, squirrels remain plentiful. In part, that’s because of their fecundity. Tree squirrels become sexually mature at six months and a female can have two litters of two to six baby squirrels each year. As a result, even though they only live a short time, squirrels are in no danger of dying out. But they do provide biologists with a puzzle: where do they live? What do they eat?

A smug grey squirrel with bird food he stole from my feeder (My camera)

A smug grey squirrel with bird food he stole from my feeder
(My camera)

And the biologists would like your help in solving the puzzle. All it takes is a pair of binoculars, a few hours, and a willingness to spy on our tree-dwelling neighbors. If you’d like to help, then why not join Project Squirrel?


January 20 – Nice Ice Babies

Today’s Factismal: Today is Penguin Awareness Day.

Today is a day of Earth-shattering importance. I do not refer to the minor affairs of politics. No! I refer to the fact that today, of all days, is Penguin Awareness Day!

Penguins are among the world’s most mis-understood animals. When they aren’t being mis-cast in cola commercials, they are being portrayed as tap-dancing dandies. In truth, the seventeen living species of penguins are far more interesting than their stereotypes. In honor of World Penguin Awareness Day, here are ten quick facts about penguins:

  1. Penguins don’t just live in Antarctica. The Galapagos Penguin lives on the Galapagos Islands, right on the Equator. In addition, there are penguins in Africa (the Africa penguin), New Zealand (Snares, Erect-crested, Yellow-eyed, and Fiordland penguins), Australia (the Little Blue penguin), and South America (King, Magellanic, and Rock-hopper penguins).

    A penguin's stomach lining; the green color comes form the krill. (My camera)

    A penguin’s stomach lining; the green color comes form the krill. (My camera)

  2. Penguins mostly eat krill. Though penguins enjoy fish when they can get it, they mostly dine on tiny little shrimpoids called krill. The problem with that is that krill is rich in fluoride, which can be poisonous in high concentration. In order to avoid that, penguins throw up their stomach linings, forming bright green puddles of goo on the shore.

    A proud Chinstrap father huddles over his chicks (my camera)

    A proud Chinstrap father huddles over his chicks (my camera)

  3. Penguin chicks don’t all hatch at the same time. If all of the penguin eggs were laid at the same time and hatched together, then the whole colony would be vulnerable to an unseasonable cold snap or strong storm. By staggering the clutches of eggs, the colony ensures that there will always be another generation. As a result, it is very common to see eggs, hatchlings, and young adults in the same colony.
  4. Like all birds, penguins just have one opening for pooping, peeing, and laying eggs. Called the cloaca, which is Latin for “sewer”, this arrangement is common in amphibians and reptiles as well.

    A Gentoo tobogganing in the snow (My camera)

    A Gentoo tobogganing in the snow (My camera)

  5. Penguins will “swim” on snow by lying on their bellies and pushing along with their feet and fins. Biologists call this “tobogganing”; everyone else just calls it cute. They do this in order to move quickly, which helps them avoid predators.

    A Gentoo gathering pebbles for his nest (My camera)

    A Gentoo gathering pebbles for his nest (My camera)

  6. Most penguins build their nests out of pebbles. Because penguins live in extreme environments, there isn’t much in the way of plant growth. So there aren’t any twigs to use for a nest. But there are lots of rocks. Building a nest out of rocks also allows the nest to drain quickly when it rains. But because there aren’t enough really good pebbles lying around, penguins will steal them from other penguins’ nests!

    The world's largest congregation of Chinstrap penguins (My camera)

    The world’s largest congregation of Chinstrap penguins (My camera)

  7. The world’s largest Chinstrap colony is on an active volcano. More than 200,000 chinstrap penguins live in one colony on Deception Island. This active volcano had its last eruption in 1969

    The barbs on penguin tongues keep their dinner where it belongs (My camera)

    The barbs on penguin tongues keep their dinner where it belongs (My camera)

  8. Penguin tongues have barbs. The barbs all point back into the throat, which helps the penguin as it tries to swallow things that would much rather be swimming away.

    Chinstrap penguins porpoising through the water (My camera)

    Chinstrap penguins porpoising through the water (My camera)

  9. Penguins are the fastest swimming bird. They can go as fast as 20 mph while porpoising. As the name suggests, porpoising means that the penguin jumps in and out of the water like a porpoise. This helps them move very quickly and keeps them out of the water where orcas and seals (both of whom think penguins are quite tasty) live.

    A Gentoo takes the plunge (My camera)

    A Gentoo takes the plunge (My camera)

  10. Penguins spend about three-quarters of their lives in the water, searching for food. It takes a lot of energy to be a bird, and it takes even more to be a bird that lives in a cold region. As a result, penguins must eat almost constantly in order to build up enough fat to survive the winter. Since their food lives in the water, that means that penguins must spend a lot of time in the water, hunting for food.

If you’d like to watch penguins as they frolic, then please hie you to

January 18 – Children Of The Sun

Today’s factismal: If you were born after 1977, you’ve never known a year that was cooler than average.

The climate numbers for 2016 are in and they are about what everyone expected; for the third year in a row, a new global temperature record was set. That makes 2016 the 40th year in a row that was warmer than average. Put another way, if you were born after 1977, the world has always been abnormally hot. Now part of those high temperatures in 2016 came from a lingering El Niño in the Pacific ocean, but El Niño comes and goes; it doesn’t last 40 years. And part of the high temperatures in 2016 came from a drop in volcanic activity which tends to lower temperature – but there have been some large eruptions in the past four decades. So why does the temperature keep going up?

The average global temperature has risen quite a bit in the past 136 years (Data courtesy NDC)

The average global temperature has risen quite a bit in the past 136 years; the blue line is the 20th century average global temperature
(Data courtesy NDC)

So why are we getting warmer? It is no secret; as a matter of fact, this very thing was predicted back in 1896 based on a discovery made in 1859. It is the CO2 that we are adding to the atmosphere. CO2 happens to block some of the “heat radiation” given off by the Earth. This is reabsorbed by the atmosphere, raising its temperature slightly. (Think of it as being like the interest given to you by a bank. You give them a dollar and every year they give you four cents more as interest. Over time, that interest builds up and so does your bank account.) Of course, lots of other factors come into play when you are talking about a planet , so the temperature change isn’t instantaneous and it has some wiggles in it. But overall, the pattern is clear: increasing CO2 increases temperature and changes climate.

The change from the 20th century average temperature. Blues are colder than average; oranges and reads are warmer than average. (Image courtesy NOAA)

The change from the 20th century average temperature. Blues are colder than average; oranges and reads are warmer than average.
(Image courtesy NOAA)

As a citizen scientist, there are two sets of things you can do. The first is to reduce the amount of energy you use; a nice benefit of this is that you also save money. For example, making sure that your tires are properly inflated will save you the equivalent of $0.10 per gallon and save the US the equivalent of 1.2 billion gallons of oil. Adding a layer of insulation to your water heater (like that blanket on your bed) will save you about $30 per year and save the US another 500 million gallons of oil. There are plenty of other way you can save money while saving the planet. But if you still want to do more, why not help record the changes that global warming is bringing to your neighborhood? Join iSeeChange and help them monitor how temperatures, weather, and other things are changing. To learn more, head to:

January 16 – Blowin’ In The (Cosmic) Wind

Today’s Factismal: The Stardust mission returned samples from a comet ten years ago today but the science continues!

There are a lot of things we don’t know in science. But there are a lot of things that we know, too. For example, we know that everything in the Solar System, from the Sun to the Earth to the smallest asteroid, all formed from the same cloud of interstellar dust and gas that collapsed some 4.5 billion years ago. But the Sun is very different from the Earth, which is very different from a comet or an asteroid. So while we know where we came from (as one astronomer used to say “We are all stardust”), how we got here is still something of a mystery. Though we have samples of the rocks on Earth, the Moon, Mars, and several asteroids, all of those have been changed by different geologic processes over the past 4.5 billion years. What we really need to understand how our Solar System formed is a sample of the original material.

The Stardust probe (NASA illustration)

The Stardust probe
(NASA illustration)

And that’s why the NASA Stardust mission happened. In 1999, NASA launched a space probe that was designed to do something that had never been done before: to go to a comet, grab samples of the dust, and return it safely to Earth. The probe looked a little like a five and a half foot long shoe box with a surfboard on either side; the two surfboards were solar panels that supplied the energy to run the instruments. Like other space probes, Stardust included a mass spectrometer to identify the composition of dust and gases it encountered and a camera to provide images. But Stardust’s heart (which was located on the front of the probe) was the sample collector.

Comet dust captured by Stardust (Image courtesy NASA)

Comet dust captured by Stardust
(Image courtesy NASA)

In order to collect samples of comet dust without damaging it or heating it up, NASA used aerogel, a material that is 99.8% empty space. Though aerogel had been invented as a bar bet in 1931, it hadn’t found a practical use until the Stardust mission (since NASA popularized the material, it has become very common in some industrial applications). Because aerogel is so light, it would stop the dust grains gradually with a minimum of breakage. And because aerogel is translucent, the tracks made by dust grains could easily be spotted by scientists.

The Wild 2 comet, as seen by Stardust (Image courtesy NASA)

The Wild 2 comet, as seen by Stardust
(Image courtesy NASA)

Both aerogel and the mission were an unqualified success. Stardust visited the asteroid 5535 Annefrank and discovered that it is larger and more interesting than previously thought. Stardust successfully captured dust both from between the planets and from comet Wild 2 and discovered that comets may not be as pure as we thought. And Stardust took the names of more than a million people (including me!) out between the planets.

During it's twelve year mission, Stardust visited an asteroid and two comets (Image courtesy NASA)

During it’s twelve year mission, Stardust visited an asteroid and two comets
(Image courtesy NASA)

Today, the samples from that mission are being analyzed by people just like you. If you’d like to take a stab at identifying dust grains and helping discover how our Solar System started, then fly on over to:

January 11 – Humble Bumble

Today’s factismal: There are 250 different species of bumblebee.

If you ask the average person what that strange critter buzzing around those flowers is, they’ll probably say “it’s a bee”. They’d probably be right but they’d also be wrong. That’s because there are over 20,000 different bee species on Earth. And even if they said it was a bumblebee (or a bumble bee – you can use either one), they’d still not be completely right because there are over 250 species of bumblebee buzzing about. In order to be perfectly right, they’d need to tell you what species it was, for example “Oh, that’s a Rusty Patched Bumblebee“.


A honeybee sipping nectar from a flower
(My camera)

And if they told you that it was one of those, you should be very happy because the Rusty Patched Bumblebee is a rare sight indeed. They used to be found everywhere from the plains of Illinois to the rose fields of Maine; more than 28 states had underground colonies of these cheerful little critters. But today they are only found in 13 states and have lost more than 90% of their population and 87% of their range thanks to a variety of factors such as changes in farming, pesticide use, and climate change. Because they are in such dire straights, they’ve been placed on the Endangered Species List joining their relatives from Hawai’i and other notable insects.


There are more than 250 different species of bumblebee!
(My camera)

So what can you do to help keep other bees from joining the list? First, plant native flowers around your home. Not only will those attract local wildlife such as bees, butterflies, and rabbits, but they’ll use less water and fertilizer making them better for the environment all around. Next, help biologists learn more about native bee species by joining Bee Germs. You’ll collect bees (it is easier than you think!) and send them in to be analyzed for germs that could be contributing to colony collapse and other problems. To learn more, buzz over to:

January 9 – Miss Demeter

Today’s Factismal: Ceres was first thought to be a comet.

Most astronomy fans know Ceres by reputation if not by name. It is the largest body in the asteroid belt, that loose pile of rubble that never quite coalesced into a real planet back when the Solar System was being built. It is small enough that you could it would take 78 chunks of rubble the size of Ceres to build one Moon. But what most astronomy fans (and other folks) don’t know about Ceres is that it has caused trouble for astronomers from the day it was found – and continues to cause trouble today!

When Giuseppe Piazzi first observed Ceres in 1801, he called it a comet. But Johan Bode decided that it was in the right place to be the “missing planet” he was looking for between Mars and Jupiter, and so he called it a planet and gave it an astronomical symbol. Unfortunately for Ceres, astronomers soon discovered over a hundred more “missing planets” in the same neighborhood, and they took to calling it a minor planet (astronomers get upset whenever there are more than ten planets; nobody knows why) when they didn’t call it an asteroid (astronomy speak for “tiny little star-like thingamabob”). And then, when yet more Pluto-sized objects were found in the outer Solar System, Ceres was reclassified yet again as a dwarf planet (see the previous note about astronomers and numbers bigger than ten).

An image of Ceres, taken by the Hubble Space Telescope

An image of Ceres, taken by the Hubble Space Telescope

Even its name is a subject for debate. In America, it is known as Ceres, for the Roman goddess of the harvest. But the Greeks have never consented to that name; they prefer to call it Demeter (which causes all kinds of confusion as there is another asteroid known as 1108 Demeter). And the Germans prefer to call it Hera for reasons that are inscrutable to anyone but a German.

Ceres as seen by the DAWN probe (Image courtesy NASA)

Ceres as seen by the DAWN probe
(Image courtesy NASA)

What is not in doubt is that Ceres is large enough to be shaped into a ball by its gravity, and that it has an interior that is divided into an icy outer part, a rocky middle section, and a metallic core (i.e., meets the definition of planet for everyone but the IAU). It is also possible that Ceres has an inner ocean between the outer icy part and the rocky middle; this is exciting because it makes Ceres one of the few places in the Solar System where life as we know it could exist. Ceres’ size and shape tell us that it is a relic of the early days of the Solar System, when everything was collapsing into small bodies that then collided to form the planets. So we can add planetismal and protoplanet to Ceres’ list of appellations.

The layers of Ceres, as we now know them. We expect to learn a lot more about Ceres once DAWN arrives there in 2015. (Image courtesy NASA)

The layers of Ceres, as we now know them. We expect to learn a lot more about Ceres once DAWN arrives there in 2015. (Image courtesy NASA)

Right now, the DAWN spacecraft is orbiting Ceres. Planetologists (i.e., the folks who still classify Pluto as a planet) are studying the asteroid in order to learn more about how planets form and develop over time, and to see evidence of the early history of the Solar System. They’ll also compare Ceres, which is the largest asteroid, with Vesta, which is the second largest and was visited by DAWN in 2013. As part of the NASA mission, JPL has launched the Asteroid Mappers website, where you can help to identify features on Ceres and Vesta: