hermit crabs will use whatever shell they can find, including this blown glass shell by robert dugrenier.
DUDE, WHERE’RE MY SATELLITES? What is humanity’s most distant spacecraft? Launched in 1977, Voyager 1 now holds that distinction at 17.5 billion kilometers from the Sun. That corresponds to 16 light-hours or 117 Astronomical Units (AU). This graphic shows the position of Voyager 1 relative to the outer solar system (top and side views) along with other distant spacecraft contenders. Next most distant, Pioneer 10 is about 15.4 billion kilometers from the Sun, though on the opposite side of the solar system from Voyager 1. Voyager 2 and Pioneer 11, both also well beyond the orbit of Pluto, are 14.2 billion and 12.4 billion kilometers from the Sun respectively. Still outbound for Pluto, the New Horizons spacecraft is presently 3 billion kilometers from the Sun and will encounter the Pluto system in July of 2015. All these spacecraft have used sling-shot style gravity assist maneuvers to increase their speeds through the outer solar system. Voyager 1 is moving the fastest though, escaping the solar system at about 17 kilometers per second. Still operational, both Voyagers are headed towards the outer boundary of the solar system, in search of the heliopause and the beginning of interstellar space. (Photo: JPL-CalTech via NASA APOD; click through for larger version)
Part of operation Fishbowl Bluegill, this is an image of an explosion of a 400 kiloton nuclear bomb taking place in the atmosphere, 30 miles above the Pacific, as viewed from above, in October 1962. (U.S. Department of Defense)
Serotonin: The Happiness Chemical
If there’s one thing you enjoy (and really there is) it’s a good dose of serotonin right between your synapses. Serotonin is typically known as the chemical that keeps you happy and is the target for most antidepressants whose role is to keep it lingering in your brain for longer. As such it’s a good idea to eat lots foods such as bananas are turkey which are rich in tryptophan, the precursor molecule for serotonin.
However serotonin has a few other roles to play, in fact 90% of serotonin present in your body is found in intestinal cells and regulates intestinal movements. A quality that is exploited by harmful bacteria (and many seeds) who secrete serotonin to trigger diarrhea. Serotonin is also the component of insect bites that causes pain but thankfully is also key in blood clotting.
What is a hypercube (also referred to as a tesseract) you say! Well, let’s start with what you know already. We know what a cube is, it’s a box! But how else could you describe a cube? A cube is 3 dimensional. Its 2 dimensional cousin is a square.
A hypercube is just to a cube what a cube is to a square. A hypercube is 4 dimensional! (Actually— to clarify, hypercubes can refer to cubes of all dimensions. “Normal” cubes are 3 dimensional, squares are 2 dimensional “cubes, etc. This is because a hypercube is an n-dimensional figure whose edges are aligned in each of the space’s dimensions, perpendicular to each other and of the same length. A tesseract is specifically a 4-d cube).
Another way to think about this can be found here:
Start with a point. Make a copy of the point, and move it some distance away. Connect these points. We now have a segment. Make a copy of the segment, and move it away from the first segment in a new (orthogonal) direction. Connect corresponding points. We now have an ordinary square. Make a copy of the square, and move it in a new (orthogonal) direction. Connect corresponding points. We now have a cube. Make a copy and move it in a new (orthogonal, fourth) direction. Connect corresponding points. This is the tesseract.
If a tesseract were to enter our world, we would only see it in our three dimensions, meaning we would see forms of a cube doing funny things and spinning on its axes. This would be referred to as a cross-section of the tesseract. Similarly, if we as 3-dimensional bodies were to enter a 2-dimensional world, its 2-dimension citizens would “observe” us as 2-dimensional cross objects as well! It would only be possible for them to see cross-sections of us.
Why would this be significant? Generally, in math, we work with multiple dimensions very often. While it may seem as though a mathematican must then work with 3 dimensions often, it is not necessarily true. The mathematician deals with these dimensions only mathematically. These dimensions do not have a value because they do not correspond to anything in reality; 3 dimensions are nothing ordinary nor special.
Yet, through modern mathematics and physics, researchers consider the existence of other (spatial) dimensions. What might be an example of such a theory? String theory is a model of the universe which supposes there may be many more than the usual 4 spacetime dimensions (3 for space, 1 for time). Perhaps understanding these dimensions, though seemingly impossible to visualize, will come in hand.
Image: Peter Forakis, Hyper-Cube, 1967, Walker Art Center, Minneapolis
The largest virus yet discovered has been isolated from ocean water pulled up off the coast of Chile.
Called Megavirus chilensis, it is 10 to 20 times wider than the average virus.
It just beats the previous record holder, Mimivirus, which was found in a water cooling tower in the UK in 1992.
Scientists tell the journal PNAS that Megavirus probably infects amoebas, single-celled organisms that are floating free in the sea.
The particle measures about 0.7 micrometres (thousandths of a millimetre) in diameter.
“It is bigger than some bacteria,” explained Prof Jean-Michel Claverie, from Aix-Marseille University, Marseille, France.
“You don’t need an electron microscope to see it; you can see it with an ordinary light microscope,” he told BBC News.
What We Recycle
In conclusion: We really need to work on that ratio..