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Orion Molecular Cloud --"A Source of the Complex Building Blocks of Life"
The spectacular new image above shows just a part of a bigger complex called the Orion Molecular Cloud, in the constellation of Orion (The Hunter). A rich melting pot of bright nebulae, hot young stars and cold dust clouds, this region is hundreds of light-years across and located about 1350 light-years from us. The orange glow represents faint light coming from grains of cold interstellar dust , at wavelengths too long for human eyes to see.
A Spectacular Interstellar Cloud --The Thermonuclear Engines of Star Creation
The Danish 1.54-metre telescope located at ESO’s La Silla Observatory in Chile has captured a striking image of NGC 6559, a cloud of gas and dust located at a distance of about 5000 light-years from Earth, showcasing the anarchy that reigns when stars form inside an interstellar cloud . The glowing region is a relatively small object, just a few light-years across, in contrast to the one hundred light-years and more spanned by its famous neighbor, the Lagoon Nebula ( Messier 8 , eso0936). Although it is usually overlooked in favor of its distinguished companion, NGC 6559 has the leading role in this new picture. The gas in the clouds of NGC 6559, mainly hydrogen, is the raw material for star formation. When a region inside this nebula gathers enough matter, it starts to collapse under its own gravity. The center of the cloud grows ever denser and hotter, until thermonuclear fusion begins and a star is born.
A team of astronomers has used the new ALMA ( Atacama Large Millimeter/submillimeter Array ) telescope to pinpoint the locations of over 100 of the most fertile star-forming galaxies in the early Universe . ALMA is so powerful that, in just a few hours, it captured as many observations of these galaxies as have been made by all similar telescopes worldwide over a span of more than a decade. The most fertile bursts of star birth in the early Universe took place in distant galaxies containing lots of cosmic dust. These galaxies are of key importance to our understanding of galaxy formation and evolution over the history of the Universe, but the dust obscures them and makes them difficult to identify with visible-light telescopes. To pick them out, astronomers must use telescopes that observe light at longer wavelengths, around one millimetre, such as ALMA. “Astronomers have waited for data like this for over a decade.
Most Prolific Star-Forming Galaxies of the Early Universe Detected by New Atacama Desert Large Array
A laboratory experiment at NASA's Jet Propulsion Laboratory , Pasadena, Calif., simulating the atmosphere of Saturn's moon Titan suggests complex organic chemistry that could eventually lead to the building blocks of life extends lower in the atmosphere than previously thought. The results now point out another region on the moon that could brew up prebiotic materials. "Scientists previously thought that as we got closer to the surface of Titan, the moon's atmospheric chemistry was basically inert and dull," said Murthy Gudipati, the paper's lead author at JPL. "Our experiment shows that's not true.
"Titan's Atmosphere Points to Building Blocks of Life" --NASA Astrobiology
Many biologists still view RNA as a messenger to shutlle inforamtion from DNA to the cell's protein manufacturing centers, ribosomes. Like DNA, RNA is a string of four different kinds of nucleotide building blocks, except that RNA has a single chain rather than DNA's iconic double helix that uses a different sugar in its molecular architecture, and substitutes uracil instead of thymine. However, unlike DNA, RNA is capable of carrying both genetic information and getting metabolic work done making it the " " molecule capabable of both reproducing itself and carrying the code to guide the needed copying. Some bacterial cells can swim, morph into new forms and even become dangerously virulent - all without initial involvement of DNA.
RNA --"DNA's Messenger or the Origin of Life on Earth?" (Weekend Feature)
The team created experiments with powerful laboratory "guns" and computer models that replicated the conditions that existed inside comets that hit Earth's atmosphere at almost 25,000 miles per hour and crashed down upon the surface. The research is part of a broader scientific effort to understand how amino acids and other ingredients for the first living things appeared on a planet that billions of years ago was barren and desolate. Amino acids make up proteins, which are the workhorses of all forms of life, ranging from microbes to people. "Our research shows that the building blocks of life could, indeed, have remained intact despite the tremendous shock wave and other violent conditions in a comet impact," Blank said.
Did Comets Deliver Amino Acids Needed for the Origin of Life on Earth? (Weekend Feature)
"We are trying to understand the chemical origins of life. One of the interesting questions is where carbohydrates come from because they are the building blocks of DNA and RNA . What we have achieved is the first step on that pathway to show how simple sugars –threose and erythrose—originated. We generated these sugars from a very simple set of materials that most scientists believe were around at the time that life began." All biological molecules have an ability to exist as left-handed forms or right-handed forms.
Clues to the Origin of Carbohydrates --The Building Blocks of DNA and RNA
New Insights into Messenger RNA --"Biology's Most Important Molecule" (Today's Most Popular)
discovered the first known mechanism by which cells control the survival of messenger (mRNA) -- arguably biology's most important molecule. The findings pertain to mRNAs that help regulate and could therefore have implications for reversing cancer's out-of-control cell division. The study was carried out in yeast cells using advanced microscope technology developed previously by Dr. Singer that has allowed scientists, for the first time, to observe single molecules in single cells in real time.
Organic chemists at the University of York have made a significant advance towards establishing the origin of the carbohydrates (sugars) that form the building blocks of life.
New Clue to the Chemical Origins of Carbohydrates --The building blocks of DNA and RNA
Messenger RNA Discovery: "Biology's Most Important Molecule" --Built-in 'Clock' Causes Its Ultimate Death
"The fate of the mRNA molecules we studied resembles a Greek tragedy," said Robert Singer, Ph.D., co-director of the Gruss Lipper Biophotonics Center and professor and co-chair of anatomy and structural biology at Einstein College of Medicine. "Their lifespans are determined at the moment of their birth." Researchers at Albert Einstein College of Medicine of Yeshiva University have discovered the first known mechanism by which cells control the survival of messenger RNA (mRNA) -- arguably biology's most important molecule.
Did Life on Earth Emerge from Non-organic Matter? (Today's Most Popular)
How did life on Earth begin? An giant step toward solving this puzzle was taken in the 1980's with the Nobel Prize–winning discovery by Tom Cech and Sidney Altman that RNA, the sister molecule of DNA, can catalyze certain chemical reactions inside cells, a job previously thought to be the exclusive domain of proteins. Until their discovery, RNA was thought to have just one function: storing the genetic information cells need to build proteins."DNA's Messenger": Harvard/MIT Researchers Discover RNA Lifecycle Key to Disease
RNA plays a critical role in directing the creation of proteins, but there is more to the life of an RNA molecule than simply carrying DNA's message.It's paradoxical that as our leading microbiologists look to create the building blocks of life in Earth-bound labs, our Universe is alive with the building blocks for DNA and RNA. The giant gas nebula in outer space are rife with sugars that form ribose --the backbone of RNA.