Because There Won't Be Another Special 'Earth' Like It For Many Many Light Years. Earth Is ~4.5 Billion Yrs Old. Life Started Early ~3.7 Billion Yrs Old. And Further Back, The Universe Is ~13.7 Billion Yrs Old. Where Did All Our Water Come From?
The Proto-Solar Nebula Made Of Dust, Gas, And Ice? Or, Later Deposited By Ice-Rich Asteroids Falling Toward The Sun From The Asteroid Belt And Outer Reaches? It Could Be Both Theories True. There Is More Ice Looking Further Out Than Inward Toward The Sun.
We Have The Whole Periodic Table Of Elements On Earth. And Haven't Yet Found Any New Elements Looking So Many Light Years Out. With The Powerful Space Telescopes' Light Spectroscopy.
And So, We Got A FULL SAMPLE/PIECE of the WHOLE UNIVERSE At Our Feet. If Not, A Close To Complete Sample Then.
First Look at Ryugu Asteroid Sample Reveals it is Organic-Rich
William Steigerwald published FEB 23, 2023
(Ref: https://www.nasa.gov/centers-and-facilities/goddard/first-look-at-ryugu-asteroid-sample-reveals-it-is-organic-rich/ )
Asteroid Ryugu has a rich complement of organic molecules, according to a NASA and international team’s initial analysis of a sample from the asteroid delivered to Earth by Japan’s Hayabusa2 spacecraft. The discovery adds support to the idea that organic material from space contributed to the inventory of chemical components necessary for life.
Asteroid Ryugu has a rich complement of organic molecules, according to a NASA and international team’s initial analysis of a sample from the asteroid’s surface delivered to Earth by Japan’s Hayabusa2 spacecraft. The discovery adds support to the idea that organic material from space contributed to the inventory of chemical components necessary for life.
NASA scientist Heather Graham receives a shipment of asteroid Ryugu samples from her colleagues at the Japan
Organic molecules are the building blocks of all known forms of terrestrial life and consist of a wide variety of compounds made of carbon combined with hydrogen, oxygen, nitrogen, sulfur, and other atoms. However, organic molecules can also be made by chemical reactions that don’t involve life, supporting the hypothesis that chemical reactions in asteroids can make some of life’s ingredients.
This conceptual image illustrates the types of organic molecules found in the sample of asteroid Ryugu collected by Japan’s Hayabusa2 spacecraft. Organics are the building blocks of all known forms of terrestrial life and consist of a wide variety of compounds made of carbon combined with hydrogen, oxygen, nitrogen, sulfur, and other atoms. However, organic molecules can also be created by non-living processes, such as chemical reactions in asteroids.
The science of prebiotic chemistry attempts to discover the compounds and reactions that could have given rise to life, and among the prebiotic organics found in the sample were several kinds of amino acids. Certain amino acids are widely used by terrestrial life as a component to build proteins. Proteins are essential to life as they are used to make enzymes which speed up or regulate chemical reactions and to make structures from microscopic to large such as hair and muscles. The sample also contained many types of organics that form in the presence of liquid water, including aliphatic amines, carboxylic acids, polycyclic aromatic hydrocarbons, and nitrogen-containing heterocyclic compounds.
“The presence of prebiotic molecules on the asteroid surface despite its harsh environment caused by solar heating and ultraviolet irradiation, as well as cosmic-ray irradiation under high-vacuum conditions, suggests that the uppermost surface grains of Ryugu have the potential to protect organic molecules,” said Hiroshi Naraoka of Kyushu University, Fukuoka, Japan. “These molecules can be transported throughout the solar system, potentially dispersing as interplanetary dust particles after being ejected from the uppermost layer of the asteroid by impacts or other causes.” Naraoka is lead author of a paper about this research published online February 23 in Science.
Solvent extractions of the Ryugu samples on a clean bench (ISO6, Class 100) inside a clean room (ISO5, Class 1000) performed by Hiroshi Naraoka at Kyushu University in Japan. JAXA
“So far, the amino acid results from Ryugu are mostly consistent with what has been seen in certain types of carbon-rich (carbonaceous) meteorites that have been exposed to the most water in space,” said Jason Dworkin of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, a co-author of the paper.
“However, sugars and nucleobases (components of DNA and RNA) which have been discovered in some carbon-rich meteorites, have not yet been identified in samples returned from Ryugu,” said Daniel Glavin of NASA Goddard, a co-author of the paper. “It is possible these compounds are present in asteroid Ryugu but are below our analytical detection limits given the relatively small sample mass available for study.”
The Hayabusa2 spacecraft collected the samples Feb. 22, 2019, and delivered them to Earth Dec. 6, 2020. They were extracted in Japan in July 2021 and analyzed at Goddard in the Fall of 2021. A very small amount of sample (30 milligrams or about 0.001 ounce) was allocated for the international soluble organic analysis team. The sample was extracted (like tea) in many different solvents in Japan and analyzed in labs in Japan, Goddard, and Europe using a vast range of machines like those in a forensics lab.
Aggregate sample of the Ryugu grains (A0106) allocated to the Hayabusa2 Initial Analysis Soluble Organic Matter Team from the Japan Aerospace Exploration Agency for a variety of organic molecular analyses. JAXA
This work is the first organic analysis of the Ryugu sample, and the samples will be studied for years. “We will do a direct comparison of the samples from Ryugu and the sample from asteroid Bennu when NASA’s OSIRIS-REx mission returns it to Earth in 2023,” said Dworkin. “OSIRIS-REx is expected to return much more sample mass from Bennu and will provide another important opportunity to look for trace organic building blocks of life in a carbon-rich asteroid.”
More about the mission and partners:
Hayabusa2 is led by the Japan Aerospace Exploration Agency (JAXA) in collaboration with the German Space Center (DLR) and the French Space Agency (CNES), and supported by NASA and the Australian Space Agency (ASA). NASA supported the research under the Consortium for Hayabusa2 Analysis of Organic Solubles.
Where Did Earth's Water Come From?
by Jesse Emspak( lifes-little-mysteries ) published July 07, 2016
(Ref: https://www.livescience.com/33391-where-did-water-come-from.html )
Look at Earth compared to other rocky planets in the neighborhood, and the first thing that would likely jump out is that there's A LOT of water. So how did 70 percent of our planet's surface become covered in this essential life ingredient?
That question is the subject of lively scientific debate, it turns out.
There are two prevailing theories: One is that the Earth held onto some water when it formed, as there would have been ice in the nebula of gas and dust (called the proto-solar nebula) that eventually formed the sun and the planets about 4.5 billion years ago. Some of that water has remained with the Earth, and might be recycled through the planet's mantle layer, according to one theory.
The second theory holds that the Earth, Venus, Mars and Mercury would have been close enough to that proto-solar nebula that most of their water would have been vaporized by heat; these planets would have formed with little water in their rocks. In Earth's case, even more water would have been vaporized when the collision that formed the moon happened. In this scenario, instead of being home-grown, the oceans would have been delivered by ice-rich asteroids, called carbonaceous chondrites.
More and more research suggests that asteroids delivered at least some of Earth's water.
Follow the water
Scientists can track the origin of Earth's water by looking at the ratio of two isotopes of hydrogen, or versions of hydrogen with a different number of neutrons, that occur in nature. One is ordinary hydrogen, which has just a proton in the nucleus, and the other is deuterium, also known as "heavy" hydrogen, which has a proton and a neutron.
The ratio of deuterium to hydrogen in Earth's oceans seems to closely match that of asteroids, which are often rich in water and other elements such as carbon and nitrogen, rather than comets. (Whereas asteroids are small rocky bodies that orbit the sun, comets are icy bodies sometimes called dirty snowballs that release gas and dust and are thought to be leftovers from the solar system's formation.)
Meteorite EET 83309 contains tiny fragments of opal, a material that requires water to form. In this backscattered electron image, a narrow opal rim surrounds a bright metallic mineral inclusion.
Scientists have also discovered opals in meteorites that originated among asteroids (they are likely pieces knocked off of asteroids). Since opals need water to form, this finding was another indication of water coming from space rocks. These two pieces of evidence would favor an asteroid origin. In addition, deuterium tends to gather farther out in the solar system than hydrogen does, so water formed in the outer regions of the system would tend to be deuterium-rich.
And on top of that, the rocky inner planets hold relatively little water (relative to their masses) compared with the icy moons of Jupiter, Saturn, Uranus and Neptune, and even the gas giants themselves. That would support the idea that in the inner system, the water evaporated, while in the outer system, it didn't. If water evaporated on Earth it would have to be replaced from somewhere else, and water-rich asteroids are abundant in the outer reaches of the system.
More supporting evidence comes from NASA's DAWN spacecraft, launched in 2007, which found evidence of water on Ceres and Vesta, the two largest objects in the main asteroid belt located between Mars and Jupiter.
A slam dunk for asteroids? Not so fast. For this scenario to work, the isotope ratio had to have stayed the same in the oceans over the last few billion years.
But what if it didn't?
Lydia Hallis, a planetary scientist with the University of Glasgow in the United Kingdom, thinks that the hydrogen present on the early Earth had much less deuterium in it than it does now. The ratio changed because in the early history of the Earth the radiation from the sun heated up both hydrogen and deuterium. Hydrogen, being lighter, was more likely to fly off into outer space, leaving more deuterium behind.
Also, in the last several years, newer models seem to show that the Earth retained a lot of water as it formed, and that the oceans might have been present for much longer than anyone thought.
Hallis and her colleagues looked at hydrogen isotope ratios in ancient Canadian rocks, some of the oldest rocks on Earth. The isotope ratios looked a lot less like asteroids and a lot more like the water one would expect from the early solar nebula in the region — the rocks had more ordinary hydrogen and less deuterium. But the current ocean ratio looks like asteroids. That would seem to indicate something changed in the last few billion years. The research was published in Science in 2015.
If the Earth's oceans were formed from water on our own planet, rather than asteroids, that would solve a couple of problems for planetary scientists. One is why Earth seems to have so much water in the first place. Another is why life, which as far as anyone knows requires water, seems to have appeared so quickly once the Earth had a solid surface.
Besides the work of Hallis, other scientists have studied ways water could be recycled from Earth's interior. In 2014, Wendy Panero, an associate professor of earth sciences at Ohio State, and doctoral student Jeff Pigott proposed the theory that Earth was formed with entire oceans of water in its interior. Via plate tectonics, that water has been supplying the oceans. They studied garnet, and found it could work with another mineral, called ringwoodite, to deliver water to the Earth's interior – water that would later come up as the mantle material circulated.
Complicating the picture, neither of these hypotheses is mutually exclusive. Asteroids could deliver water while some could come from the Earth's interior. The question is how much each would deliver — and how to find that out.
So this mystery will remain one, at least for a little while longer.
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