Craters: Hercules & Atlas

Most observers prefer to study only the lunar features that are close to the terminator, the line that separates the dark regions of the Moon from the illuminated areas. This is where the shadows are most prominent and vertical features (crater rims and mountains) are shown in strong relief. Personally, I think that it is just as interesting to observe lunar features when they are far from the terminator and fully illuminated. It is under these conditions that the various tonal differences of the lunar surface are best seen. Here are the craters Hercules and Atlas under both lighting conditions.

Hercules & Atlas
Hercules & Atlas

 

Pecopteris

Southwestern Pennsylvania is coal country, and many of the fossils found in this area are of plants that date back to the Pennsylvanian Period of the Paleozoic Era (280 million to 325 million years ago). Not to be confused with modern ground dwelling ferns, Pecopteris was part of a tree-like plant called Psaronius, that reached heights of 15 meters (50 feet) and had a base over 1.5 meters (5 feet) in diameter. What we see in this fossil is not a plant in its entirety, but just the leaves of a “tree”. The reason the leaves have their own name is that prior to the discovery of an entire fossilized Psaronius, Pecopteris was believed to be a self-contained fern that grew at ground level.

Pecopteris
Pecopteris

I AM BACK

After an extended absence I am back. Not just to here, but to a number of other aspects of my life. The length of my absence from other aspects must be measured in years, not just weeks. But I am back none the less

Filamentous Algae

The long and slimy filaments of green algae that often cover the surface of stagnant ponds (and now blooming in Lake Erie) may be repulsive to the naked eye, but some can be quite attractive under the microscope. Here are an unremarkable algae and a strand of Spirogyra, generally considered to be the most beautiful of the filamentous algae.

Filamentous Alga – Genus: Unknown
Filamentous Alga – Genus: Unknown
Filamentous Alga – Genus: Spirogyra
Filamentous Alga – Genus: Spirogyra

Mold – Rhizopus

Common names can be useful in casual circumstances, but can also be the cause of much confusion and many inaccuracies. Many of the molds that grow on bread belong to the genus Rhizopus and so we call all species of Rhizopus “Bread Mold” – even though there are over 100 different species of Rhizopus and not all of them grow on bread.

Another problem is that the name Bread Mold promotes the false assumption that molds can be classified by the type of material that they grow on. If Bread Mold grows on bread, then the mold that grows on tomatoes must be different, perhaps Tomato Mold. And the mold that grows on plums must be Plum Mold – and on, and on, and on. Even though it is so prevalent that most “household” molds are likely to be Rhizopus, we would never refer to them as Bread Mold unless they were actually growing on bread.

Having said all that – this lovely specimen of Rhizopus was not found growing on bread or on anything else, it was in a tub of rainwater.

Mold Spore Case – Genus: Rhizopus
Mold Spore Case – Genus: Rhizopus

 

Tardigrade (Water Bear)

Tardigrades are fascinating little creatures with a phylum all their own. If they dry out they go into a state of “suspended animation” but can be revived at a later date by the simple addition of water. It would be interesting to see how many times a single Tardigrade could go through that process before it failed to reanimate. Of course, there are many variables that would enter into the equation: The length of the active and inactive periods, the intake of food during the active state, and numerous other factors related to both the Tardigrade itself and its environment.

Water Bear - Phylum: Tardigrada – Class: Eutardigrada
Water Bear – Phylum: Tardigrada – Class: Eutardigrada

Lunar Features: Rilles

I took this image to record the many surface cracks (rilles) in this region near the center of the visible side of the Moon. The most prominent ones, pierced in the middle by the small crater Hyginus, are sections of the crust that have sunk between two parallel faults. The less obvious ones surrounding the crater Triesnecker, are probably collapsed lava tubes. Finding rilles, and imaging them, is great sport for many lunar enthusiasts.

Network of rilles at Hyginus and Triesnecker
Network of rilles at Hyginus and Triesnecker

Protozoan – Tetrahymena

One way of classifying protozoans is by their method of locomotion. Amoeboids move around by changing their shape and “oozing” in the direction they want to go. Flagellates swim by using one or two whip-like organs. Ciliates are covered with fine hair-like structures that propel the organism with a paddling motion. Tetrahymena are common ciliates. Some species are divided into seven distinct sexes that can mate in 21 different combinations.

Ciliated Protozoan – Genus: Tetrahymena
Ciliated Protozoan – Genus: Tetrahymena

Eastern Garter Snake

This is a snake that is very common in our area; the Eastern Garter Snake. We usually think of all snakes as having pupils that are vertical slits. Some do, of course, but only the venomous ones. Non-venomous snakes, like this friendly fella, have round pupils.

Eastern Garter Snake - Thamnophis sirtalis
Eastern Garter Snake – Thamnophis sirtalis

Airplane & Moon

If you take enough pictures of the Moon, and live close to an airport, sooner or later you are going to get one of these. The same principle applies when taking any type of nature photo. Take enough of them and you will capture predators and their prey, insects mating, cells dividing or any number of images that might be called the result of luck – when actually they are the product of persistence.

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