With a space telescope churning out discoveries of new planets, robots exploring Mars and other places, and researchers gaining understanding of extreme environments, the search for the roots of life on Earth and other planets is in a golden age, an authority in the field said Wednesday (March 23).“If there ever was a moment to think about the origins of life, it surely is now,” said Ralph Pudritz, director of the Origins Institute at Canada’s McMaster University.Pudritz spoke at one of the regular forums sponsored by Harvard’s Origins of Life Initiative, an interdisciplinary, cross-school center aimed at unraveling one of the central mysteries facing humankind: how life arose in the universe. Origins Director Dimitar Sasselov, professor of astronomy, introduced Pudritz as the founding director of a sister organization of Harvard’s initiative: McMaster University’s Origins Institute, which was begun in 2004.Pudritz’s talk, “Equipping Planets for Life,” reviewed recent advances in understanding planetary formation and what it takes to create the conditions and elements of life.Pudritz acknowledged that our imaginations fail when thinking about exotic forms of potential life, but added that our current understanding of the process has a handful of requirements. Life is thought to exist only on rocky planets in the presence of water and an energy source with a supply of the biomolecules that make up living things.Planets form by the accretion of material in a dusty disk around young stars. That material, Pudritz said, commonly includes ample water. Water is so common, in fact, that Pudritz said one study found that typical planets contain more water than Earth does.Water alone doesn’t guarantee life. A rocky, watery planet must orbit in a star’s habitable zone, that narrow band whose extremes are defined in our solar system by Venus and Mars. Too close to the sun and water evaporates. Too far and it freezes.The Kepler space telescope has given an enormous boost to this research, Pudritz said, by discovering more than 1,000 planets, some of which are thought to lie within this habitable zone.“It looks like we’ve hit pay dirt,” Pudritz said.Scientists believe that life arose on Earth around 3.5 billion years ago. Before that, the planet existed, lifeless, for a billion years. The conditions for life were developed in what Pudritz referred to as a “prebiotic soup” that contained, among other things, the necessary molecules.Science has begun to answer the question of where those molecules originated, Pudritz said. Analysis of meteorites that have fallen to Earth have shown that some of them are rich in amino acids, the molecules that make up the proteins so important to life. His own research, published in 2009, illustrated that the 10 simplest amino acids used in living things are the easiest to create naturally and were likely available in the environment before life arose. More complex amino acids utilized in living things were probably added to the genetic code as life evolved.“It appears that the makeup of the soup is determined by a simple law of physics,” Pudritz said.
The Clear Case for Microgrid Development in Puerto Rico FacebookTwitterLinkedInEmailPrint分享MicroGridKnowledge.com:With the focus now on survival, most Puerto Ricans are probably not thinking about long-term energy planning. But “there is a huge opportunity, one or two years out, for building the grid in a more sustainable way,” said Cathy Kunkel, an energy analyst with the Institute for Energy Economics and Financial Analysis.Kunkel is deeply familiar with Puerto Rico’s power woes, which began long before the hurricane. Brought to the island two years ago to help an environmental organization, she has been focused on utility rate and resource planning issues.Rebuilding will not be easy, she warned. The utility was besieged by debt prior to the hurricane and has an old-school grid, heavily reliant on aging, oil-fired power plants.“It was a horrible lump for them that it was the worse hurricane since 1928. That would have done damage to the best of grids,” Kunkel said.Besides lacking capital, Puerto Rico’s electricity industry struggled under competing visions for the future even before the storm, according to Kunkel. PREPA wanted to retain a centralized grid, but switch power plants from oil to liquified natural gas (LNG). Since the island has no LNG, the utility sought permission to build a terminal so that it could import the fuel.Others like Kunkel advocated for more decentralization and renewable energy to strengthen the system.No decision had been made on the LNG terminal before Hurricane Maria. Kunkel pointed out that had it been built, chances are it may have been damaged by the storm.“Hurricane Maria shows the dangers of the path PREPA was trying to go down,” she said. “The frustrating thing to me is that it’s unreasonable to say they didn’t see this coming. It is a tropical island that was in the path of hurricanes and had a decrepit grid running on a shoe string. We’re seeing the consequences of that.”But now Puerto Rico could remake itself into “the poster child for distributed energy,” she said.“If you’re talking about building a grid from scratch, I don’t know why you wouldn’t rebuild it in a much more decentralized way,” she said. “We have the technology now to do it. You certainly can set it up in a way where hospitals and emergency centers would not go dark and would not be relying on diesel fuel in an emergency. Generators are good backup, but only when they do not run out of fuel.”Microgrids typically have more than one form of generation. On a sunny island, that’s likely to include solar and batteries, along with backup generators.More: The Sky Fell in Puerto Rico. The Microgrid Argument is not Chicken Little
The Football Player of the Club Sarajevo Asmir Suljić yesterday in Budapest signed up a contract with the Hungarian first league UJPEŠT.Suljić had previously undergone regular medical examinations.However, Suljić until the official departure to Hungary will play another match on Saturday against Olimpic in Otoka. After that he will leave to UJPEŠT.(Source: Dnevni Avaz)