Researchers used a multicollector ion microprobe to study hydrogen-deuterium ratios in lunar rock and on Earth. Their conclusion: The Moon's water did not come from comets but was already present on Earth 4.5 billion years ago, when a giant collision sent material from Earth to form the Moon.
Water inside the Moon's mantle came from primitive meteorites, new research finds, the same source thought to have supplied most of the water on Earth. The findings raise new questions about the process that formed the Moon.
The Moon is thought to have formed from a disc of debris left when a giant object hit Earth 4.5 billion years ago, very early in Earth's history. Scientists have long assumed that the heat from an impact of that size would cause hydrogen and other volatile elements to boil off into space, meaning the Moon must have started off completely dry. But recently, NASA spacecraft and new research on samples from the Apollo missions have shown that the Moon actually has water, both on its surface and beneath.
By showing that water on the Moon and on Earth came from the same source, this new study offers yet more evidence that the Moon's water has been there all along.
The genetic code is the set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins (amino acid sequences) by living cells.
Specifically, the code defines a mapping between tri-nucleotide sequences called codons and amino acids; every triplet of nucleotides in a nucleic acid sequence specifies a single amino acid.
Because the vast majority of genes are encoded with exactly the same code, this particular code is often referred to as the canonical or standard genetic code, or simply the genetic code, though in fact there are many variant codes; thus, the canonical genetic code is not universal.
For example, in humans, protein synthesis in mitochondria relies on a genetic code that varies from the canonical code. The genome of an organism is inscribed in DNA, or in some viruses RNA.
The portion of the genome that codes for a protein or an RNA is referred to as a gene.
Those genes that code for proteins are composed of tri-nucleotide units called codons, each coding for a single amino acid.
Each nucleotide sub-unit consists of a phosphate, deoxyribose sugar and one of the 4 nitrogenous nucleotide bases.
The purine bases adenine (A) and guanine (G) are larger and consist of two aromatic rings.
The pyrimidine bases cytosine (C) and thymine (T) are smaller and consist of only one aromatic ring.
In the double-helix configuration, two strands of DNA are joined to each other by hydrogen bonds in an arrangement known as base pairing.
These bonds almost always form between an adenine base on one strand and a thymine on the other strand and between a cytosine base on one strand and a guanine base on the other.
This means that the number of A and T residues will be the same in a given double helix as will the number of G and C residues.
In RNA, thymine (T) is replaced by uracil (U), and the deoxyribose is substituted by ribose.
Excerpts from Sciencedaily!!
Spider silk is not a single, unique material--different species produce various kinds of silk. Some possess as many as seven distinct kinds of glands, each of which produces a different silk.
All spiders make so-called dragline silk that functions in part as a lifeline, enabling the creatures to hang from ceilings. And it serves as a constant connection to the web, facilitating quick escapes from danger. Dragline silk also forms the radial spokes of the web; bridgeline silk is the first strand, by which the web hangs from its support; yet another silk forms the great spiral.
Dragline silk combines toughness and strength to an extraordinary degree. A dragline strand is several times stronger than steel, on a weight-for-weight basis, but a spider's dragline is only about one-tenth the diameter of a human hair.
Dragline silk is a composite material comprised of two different proteins, each containing three types of regions with distinct properties. One of these forms an amorphous (noncrystalline) matrix that is stretchable, giving the silk elasticity. When an insect strikes the web, the stretching of the matrix enables the web to absorb the kinetic energy of the insect¿s flight. Embedded in the amorphous portions of both proteins are two kinds of crystalline regions that toughen the silk. Although both kinds of crystalline regions are tightly pleated and resist stretching, one of them is rigid. It is thought that the pleats of the less rigid crystalline regions not only fit into the pleats in the rigid crystals but that they also interact with the amorphous areas in the proteins, thus anchoring the rigid crystals to the matrix. The resulting composite is strong, tough, and yet elastic.
The Scientists say that the Super-Earths could have oceans of liquid metal and life-protecting magnetic shields. Under the heat and pressure that exists inside super earths, magnesium oxide and other minerals commonly found in the rocky mantles of terrestrial planets, transform into liquid metals.
Super-Earths are planets beyond the so;ar system that are bigger than earth but smaller than gas giants like neptune. Scientists zapped a piece of magnesium oxide with high powered lasers to simulate the heat and pressure that would exist on planets roughly three to 10 times as massive as Earth. They discovered that the clear ceramic mineral first morphed into a solid with a new crystal structure, then completely transformed into a liquid metal. In that state, the liquid mineral may be able to sustain a physics phenomenon called a "dynamo" action., which is responsible for generating magnetic fields.
A small British firm claimed to have developed a revolutionary new technology that can produce petrol using just air and electricity. This technology is called as "Air Capture Technology". This technology is used to create synthetic petrol which experts have hailed as a potential gamechanger in the battle against climate change and a saviour for the world's energy crisis. The technology works by removing carbon dioxide from the atmosphere. The 'petrol from air' technology involves taking sodium hydroxide and mixing it with carbon dioxide before 'electrolysing' the sodium carbonate that it produces to form pure carbon dioxide. Hydrogen is then produced by electrolysing water vapour captured from the dehumidifier. The company, air fuel syndication, uses the carbon dioxide and hydrogen to produce methanol which in turn is passed through a gasoline fuel reactor, creating petrol. The fuel produced can be used in any regular petrol tank and if renewable energy is used to provide electricity it could become completely carbon neutral.
Scientists have found that small patches of ice could make up five to 10% of material inside a permanently shadowed lunar crater located near the Moon's south pole.
the small tilt of the lunar spin axis means shackleton's interior is permanently dark and very cold. These are the first orbital radar measurements of the shckleton crater. The observations are consistent with the presence of small amounts of ice in the rough inner wall slopes of the crater. The interior of this crater lies in the permanent shadow and is a 'cold trap' - a place cold enough to permit ice to accumulate.
The phenomenon of Plate tectonics which was previously thought to exist only in the planet Earth has now also known to be occuring beneath the surface of Mars. The scientists have found that the geological phenomenon, which involves movement of huge crustal plates beneath a planets surface, also exists on the red planet. Mars is at the primitive stage of plate tectonics. It gives us a glimpse of how early earth may have looked and may have helped us understand how plate tectonics began on earth.
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