2023 Last Day Of School Autograph 5th Grade Graduation Party Shirt

2023 Last Day Of School Autograph 5th Grade Graduation Party Shirt

A fundamental premise of physics is that the 2023 Last Day Of School Autograph 5th Grade Graduation Party Shirt are the same everywhere. That implies whatever initial conditions led to life as we know it will almost certainly occur elsewhere. Only a few years ago, we had no evidence there were even extrasolar planets. Now we know there are thousands relatively nearby, so it looks like our solar system is somewhat typical for stars like ours and that our star is for better or worse, utterly typical. Ergo there are billions of planets out there in our galaxy alone. The argument that we are the only sentient beings because we haven’t heard from any others is (of course) theoretically possible, but highly unlikely. Given the argument above, it’s far more likely the universe is literally teeming with life at various stages of evolution. But even in our little corner of the Milky Way, we don’t hear from them because they are just too damn far away. One light year is 9.46×10^15 meters. None of our own random EM radiation so far would be more than (say) a thousand watts/m^2 at its origin and most of it far less than that. A fraction of that would actually make it out into space where it would just spread out in a spherical wave front. Let’s assume for giggles that it all does and that our alien buddies are also shouting randomly at the cosmos at roughly the same volume (power output).

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2023 Last Day Of School Autograph 5th Grade Graduation Party Shirt, Hoodie, Sweater, Vneck, Unisex and T-shirt

Best 2023 Last Day Of School Autograph 5th Grade Graduation Party Shirt

The key to understanding the 2023 Last Day Of School Autograph 5th Grade Graduation Party Shirt of abundant sea life has to do with the winds as well. In most of the ocean, biologically available nitrogen and phosphorus come from relatively deep in the ocean, where biological production is low, and thus these nutrients are not exhausted. The two main mechanisms by which N and P become available in the upper photic (sunlit) zone are strong mixing, due to a strong winter storm or tropical cyclone, and upwelling along the coasts or driven by wind convergence near the equator. The important thing here is that, with little to no wind over a large area of ocean, the nutrient levels are extremely low. Low nutrient levels have the obvious consequence of inhibiting phytoplankton growth, often referred to as primary production, as it involves direct photosynthesis and is how most chemical energy is made available to ocean life. Areas of extremely low primary productivity can be seen in the following satellite image of ocean color.

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