2005年8月23日 · I am working on a school project called biosphere 3. We are creating a biosphere on mars. We have to choose what kind of people will be in the biosphere, the types pf supplies, and we have to draw a the structure of our biosphere. Any help would be greatly appreciated!!!L2L

2024年4月2日 · The LUCA has also been defined as "a hypothetical organism ancestral to all three domains".[3] The LUCA is the point or stage at which the three domains of life diverged from preexisting forms of life (about 3.5–3.8 billion years ago). The nature of this point or stage of divergence remains a topic of research.

2024年4月2日 · "Scientists think that by 4.3 billion years ago, Earth may have developed conditions suitable to support life. The oldest known fossils, however, are only 3.7 billion years old." " Red dwarf stars live fantastically long lives, gently sipping on hydrogen to power a slow but steady fusion reaction. But eventually, all stars, including the red ...

2006年2月4日 · UCLA paleobiologist J. William Schopf and colleagues have produced 3-D images of ancient fossils - 650 ...

2024年11月19日 · This is equal to a Mass Density of about 3.3474E−28 kg / cubic meter. This is estimated to be about 4% of the universe's total mass density. The equivalent Energy Density = 3.0085E-11 J / cubic meter. Dark matter forms about 22% of the universe (as per estimates), which gives an average Mass Density of about 1.8411E-27 kg / cubic meter. Dark ...

2024年10月24日 · Luminosity of the Sun, L⊙ = 3.8E33 erg per sec. A main sequence star with 20 times the mass of the sun has a luminosity of (20^3.5) L ⊙, about 35,000 times the luminosity of the Sun! Therefore, a 20 M ⊙ star has a luminosity of ~ 10E38 erg per sec, one order of magnitude greater than an average pulsar.

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2007年2月24日 · All Activity; Home ; Social Science Forums ; Music Studies ; What are you listening to right now?

2024年1月19日 · for every number there is exactly one square; hence, there cannot be more of one than of the other. This is an early use, though not the first, of the idea of one-to-one correspondence in the context of infinite sets (wikipedia) A = 1,2,3,4,5..... B = 1,4,9,16,25 They say that A and B are both eq...

2007年8月17日 · This one's giving me a headache.du/dt = K*laplacian(u) inside a 3D sphere, r<a. Boundary conditions u(r=a) = 0. Initial conditions are u(t=0, 0<r<a/2) = 1, u(t=0, a/2<r<a) = 0. Obviously this is spherically symmetric, so u doesn't depend on the angles (phi and theta). Then by …