Explore Nature& Air Resources Division-Natural Lightscapes The darker the sky, the more stars can be seen. The following simulated images depict how the constellation Orion appears under various sky conditions. Images are courtesy of GLOBE at Night. How good is your sky at home? Limiting Magnitude=2. Limiting Magnitude=4. Limiting Magnitude=6. Limiting Magnitude=7.
Molecular Expressions Microscopy Primer: Interactive Java Tutorials - Virtual Microscopy: Magnification Interactive Java Tutorials Magnification Module This interactive Java tutorial explores the effect of increasing magnification (equivalent to changing microscope objectives) on the ability to resolve features in a sample. To operate the tutorial, first use the pull-down menu to select a sample for viewing. Important Note: Once all 6 magnifications have been downloaded locally to your computer, selecting between them will become much quicker because they already exist in your browser's cache. Click Here if you need help with operation of the virtual microscope. Contributing Authors Mortimer Abramowitz - Olympus America, Inc., Two Corporate Center Drive., Melville, New York, 11747. Matthew J. Questions or comments? This website is maintained by ourGraphics & Web Programming Team in collaboration with Optical Microscopy at theNational High Magnetic Field Laboratory.
Micrographia: A Light Microscopy Resource: Home Page and Site Directory. Trailspace.com: The Backcountry Gear Guide Profiles of microorganisms: the microbial world We should note a technical point about this tree: the comparison of ribosomal RNA gene sequences can show the possible relatedness of organisms, but other information is needed to provide the root of a tree. One of the principal modes of evolution is thought to involve gene duplication followed by divergence. The original gene retains its vital function, while the copy can change and ultimately can encode a new function. If these paralogous gene pairs can be identified by sequence similarity, then the original gene should be present in all organisms whereas the new version will be present only in the more recently derived organisms. The root for the tree in the diagram above was determined by using paralogous genes for translation elongation factors involved in synthesis of protein chains on the ribosomes. Domains and Kingdoms The proposed universal phylogenetic tree recognises three Domains of organisms (Bacteria, Archaea and Eucarya) above the traditional level of Kingdoms. The archaea
Extreme Environments - StumbleUpon People Get Thirsty in Winter, Too by Karen Berger from GORP In cold weather camping, one of the best things you can do to stay healthy is develop a drinking habit. I'm talking water, not wine. Adequate hydration is key to avoiding hypothermia and altitude sickness. But what if you're camped in a vast expanse of snow where everything is frozen? In freezing cold weather, look for flowing water.
What causes the smell after rain?" Most people notice a distinctive smell in the air after it rains. It's frequently linked with spring, as the smell of fresh cut grass is associated with summer. You'll find it in a lot of poetry and also on many inspirational lists of things to be happy about. But what causes it? As it turns out, the smells people associate with rainstorms can be caused by a number of things. Another sort of smell is caused by the acidity of rain. Another after-the-rain smell comes from volatile oils that plants and trees release. These are a few common rain smells, but there are also all sorts of other scents after it rains. BioLite