Science is fun. It’s not always easy fun; but it’s fun.
About 6 years ago the Discovery Channel ran a couple of commercials known as “I Love the Whole World”. Although it has not appeared on TV for quite a while, it is so catchy that many people continue to write their own versions of it.
First watch the two originals at: https://www.youtube.com/watch?v=NVP4l2dSyYw
Then, when you have become familiar with the melody, add my lyrics in your head:
Cones are a great way to identify coniferous trees. Not only are they useful in that respect, they can be quite interesting in their own right. They come in an attractive variety of shapes and sizes, are easy to find since they all eventually fall to the ground, and are perfect for those who enjoy building manageable collections of natural objects. Collectors would be wise to place them in a 250 degree oven for several minutes to kill any little critters that might be hiding in the many nooks and crannies cones provide.
Here are two pine cones I recently encountered on one of my local nature walks:
Sugar Pine – Pinus lambertiana
Shortleaf Pine – Pinus echinata
The Moon is generally considered to be a dead world where nothing ever happens; this is not entirely true. There are still plenty of small asteroids flying around our part of the Solar System. Those which strike the Earth’s atmosphere will usually burn up before they can impact the surface. The Moon, not having an appreciable atmosphere, cannot prevent them from colliding with its surface. Craters created by those lunar impacts are rarely large enough to be detected by ground based telescopes but lunar orbiting cameras are a different matter.
LROC (the Lunar Reconnaissance Orbiter Camera) has imaged several of these small new craters in recent years. Here are images taken before and after one of these craters was formed.
LROC image taken February 12, 2012
LROC image taken July 28, 2013
The bright new crater was formed by an impact on March 17, 2013 and measures approximately 18 meters (59 feet) in diameter.
Today marks the 45th anniversary of the first manned landing on the Moon. The landing site was on Mare Tranquilitatis, the Sea of Tranquility. It was not selected because it was an interesting place to land but because it appeared to be the safest – flat, smooth, and near the center of the visible side of the Moon. Interestingly, Neil Armstrong did not set foot on the Moon until six hours after the landing, which made it 2:56 UTC (Universal Coordinated Time) July 21, 1969.
Apollo 11 landing site marked by red X
The last manned mission to the Moon was in 1972. Since that time no manned flight has left Earth orbit – the equivalent of men in ships, after discovering the new world, spending the next 40+ years just sailing up and down the coast of Europe.
In addition to enhancing the main subject, one of the advantages of phase contrast illumination is its ability to make visible many small and transparent objects that cannot be seen under bright field illumination.
Rotifer – Class Bdelloidea
In the image above, notice the trail of bright objects streaming from beneath the Rotifer. Under bright field illumination they were not visible. However, there is more to be seen than the Rotifer and this trail. In the eyepiece one can also see the whirlpools of matter created by the twin circles of cilia on the Rotifer’s head, but they do not show up in a still photograph. It takes motion to fully duplicate the eyepiece view.
Click on the link below to see a phase contrast video that shows not only the trail of streaming objects but the whirlpools as well.
Arcella as seen from above
Arcella is a Testate Amoeba whose shell (test) is rather squat, much like a turtle’s. Its pseudopodia extend from an opening in the bottom. Sometimes a sudden rush of water or a large passing creature will flip it onto its back. This is serious for the Arcella since its pseudopodia do not extend far enough for it to reach the “ground” and right itself.
Inverted Arcella seen from the side
In such a situation, the Arcella will develop an air bubble near the inner edge of its test. The bubble will rise, causing the Arcella to stand on its end. The pseudopodia can then extend far enough to reach the substrate and the amoeba will right itself. When it is no longer needed, the air bubble will dissolve and the Arcella can resume it normal life.
When I found this feather, it was obvious that it came from a fairly large bird; it measured 8-1/4 inches from tip to base. And it was a flight feather, not a body feather; note that the main vein is not centrally located
An excellent website for feather identification can be found at: Feather Atlas
I quickly narrowed it down to either a Cooper’s Hawk or a Sharp-shinned Hawk; then eliminated the Sharp-shinned. If it were a Sharp-shinned Hawk feather it would have had a large white spot near the base; otherwise they are just about identical.
I added the feather to my modest collection of a couple dozen which fills a large drinking glass on a shelf in my home office.
Cooper’s Hawks are fairly common in our area and, as is often the case, so are the nearly identical Sharp-shinned Hawks. The image below was taken at quite a distance and so is not suitable for making a positive identification.
Cooper’s Hawk – Accipiter cooperii
There are, of course, other means of making an ID. One of them is the behavior of the critter. A Cooper’s Hawk (but not the Sharp-shinned) will pluck the feathers from its prey before it flies off with it – as this hawk did. That pretty much sealed the deal.
Exploring a drop of “living” water is always an adventure; you never know what you will find. Some micro-critters are immediately identifiable, especially as your experience grows. Others take extended research to identify. One factor that can complicate the process is the angle of view one gets of the organism. When normally seen from the top, an organism that is seen from the side can look quite different. In fact, one can sometimes think that it is a completely different species. Fortunately this diatom, Genus: Hantzschia, was observed as it slowly rotated so there is no doubt that it is the same critter.
The word “Amoeba” immediately brings to mind a formless blob of protoplasm that has no permanent shape. These are commonly called Naked Amoebas.
But there is another large group of Amoebas that possess a shell (test). They are known as Testate Amoebas. Some, like Difflugia, build their tests by gathering debris from their immediate surroundings.
Others, like Euglypha, secrete their test from within.