Twinkle, twinkle, little stBOOM! The explosions of some dying stars are so powerful yet so rapid, mere measurements seem inadequate to describe them. Two death-star events were reported in recent articles. Despite the bravado of textbook orthodoxy, the articles both mentioned that astronomers really don’t understand what’s going on all that well. Eta Carina is one of the most intriguing stars in the southern sky. Its twin-lobed, bloated bubble blown out by the eruption of 1843 has given it the name the Homunculus Nebula (see dazzling photograph on Astronomy Picture of the Day for June 17). The 1843 bubble, and another estimated to be a thousand years old, have been well known. Astronomers recently detected, however, a newer, more powerful eruption that is catching up to the bubble. National Geographic News reported that this material is moving outward at 1.5 million miles per hour. It is so energetic it borders on the power of a supernova – the explosion that usually ends a large star’s life. Is this a supernova imposter? Team lead Nathan Smith (UC Berkeley) commented, “It means, essentially, that we still don’t fully understand what is going on in the deep interiors of massive stars shortly before they die.” If you think that boom was big, wait till you hear about the latest gamma-ray burst that was seen March 19. Gamma-ray bursts are the most powerful explosions in the universe. They were only discovered in the late 1960s. EurekAlert said this one, numbered GRB 080319B, was aimed directly at earth. Good thing it was 7.5 billion light-years away. Its jets were blasting material our direction at 99.99995 percent the speed of light, the article claims. Within 15 seconds of detection by the orbiting Swift satellite, it had become bright enough to be seen with the naked eye – even from that astronomical distance. That’s powerful. Red dwarf stars, like soldiers, slowly fade away. Larger stars shed their outer envelopes fairly calmly before retiring as white dwarfs. Supernovas explode, growing to maximum brightness over a few days or weeks, and then dimming for months as they form neutron stars, pulsars or black holes. Gamma-ray bursts are the flashbulbs of the cosmos. Most appear for 10 seconds or less. Some can flash as brief as a few thousandths of a second. That’s why it took so long to discover them; you have to be looking at the right place at the right time. Moreover, astronomers did not realize anything could be so energetic. Do astronomers understand these colossal explosions? They certainly have models. National Geographic explained, though, that “As a star’s core collapses, it creates a black hole or neutron star that, through processes not fully understood, drive powerful gas jets outward.” When the jets impact gas previously ejected in earlier explosions, they heat the gas, which astronomers detect as afterglows. Some astronomers still find it so hard to believe that explosions this bright can be seen from billions of light-years away. They have argued that they must be nearby objects. It’s almost unfathomable that any process could produce so much energy so quickly. The narrow beams of the burst are emitted from the poles of the spinning star or black hole. Astronomers believe an ultra-fast component of the beam from GRB 080319B beam was just 0.4 degree across. Because this rare “jackpot” burst was aimed right along our line of sight, it is providing astronomers with new data – and more questions – as they seek to understand these astonishing explosions.Data on scientific objects is always incomplete. The explanations about them, therefore, are also necessarily incomplete. If star death, which can be observed in a flash, is poorly understood, how about star birth which, because theory says it takes millions of years, cannot be observed from start to finish? Astronomers piece together stages of star birth from actual stars presumed to be at different stages. The charts and explanations sound convincing. One must ask, though, whether this approach assumes what needs to be proved. Deciding that stars evolve, and then putting them into an evolutionary sequence, is circular reasoning. We can see stars age. We can see them die. But we can only theorize from laws of gravity, diffusion, viscosity, nuclear physics, quantum mechanics and other principles what a gas cloud would do, given millions of years. Stars are not irreducibly complex structures like those in biology. They do not contain information. It seems reasonable to trust models of star birth from well-known laws that have been amply confirmed in the lab. There are many examples in the history of science, though, when plausible models turned out to be wrong. Usually, the real world proves more complex than the models. If we struggle with modeling processes that can be observed in a flash, we should at least retain a certain level of humility about scientific models of unobservable processes, and hold them in a tentative way.(Visited 9 times, 1 visits today)FacebookTwitterPinterestSave分享0
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Share Facebook Twitter Google + LinkedIn Pinterest Donald Gwynn “Donnie” Parrott, 50 of Magnetic Springs, passed away unexpectedly Friday morning, April 28, 2017 at the Memorial Hospital in Marysville.He was born November 9, 1966 in Kenton to William and Sally (Sanders) Parrott, and they both survive.On February 24, 1990, he married the love of his life, Connie Colvin in Marysville, and she survives.Donnie loved life, it’s as simple as that. He instilled into his children how it was to truly live and enjoy life to the fullest with no regrets and with hearts full of adventure. He enjoyed taking annual hunting trips to Wyoming with his father. He was a man who never met a stranger; those who didn’t know him knew of him and how truly great a man he was. He loved his wife and kids unconditionally and was truly at home when they were all together. He enjoyed coaching his kids in their various activities, including North Union Junior Football.He was a lifetime member of Magnetic Springs United Methodist Church where he had served in various leadership positions. A 1985 graduate of North Union High School, Donnie earned his Bachelor’s Degree from Wilmington College before returning to Richwood in 1989 to join the family business, Parrott Implement. He started at the bottom, learning every aspect of the business, working his way through the ranks to presently successfully managing the company.He was a very active member and supporter of various clubs and associations in the community, especially, North Union Ag and sports. Most notably, he and his family have been instrumental in organizing and supporting NUAC, which benefits athletic facilities at North Union. Donnie was the guy who made things happen. He was a member of The Eagles and The Elks of Marysville. He truly enjoyed spending time with his many friends, golfing and genuinely enjoyed his time with them. Donnie truly understood how precious and special time was when spent with those that he loved. He went above and beyond in any endeavors that he would tackle, not to mention being a great salesman, a “social” golfer, and farmer.Donnie was born and raised in Magnetic Springs south of the creek, which is where he learned the values and morals of being a selfless person willing to help anybody without a question asked. He will truly be missed as not only a loving husband, phenomenal father, and the best friend that anyone could be lucky enough to have. Donnie had hundreds of sayings that people enjoyed, but many will remember Donnie saying with a wink and a smile, “You used to be fun.”Besides his wife and parents, he is survived three children, Billy Parrott, Columbus; Sydney Parrott, Magnetic Springs; Sawyer Parrott, Magnetic Springs; three sisters, Jean (Nevin) Smith, Marysville; Rita (Jim) Monroe, Essex; Anne (Damon) Crabtree, Marysville; a brother-in-law, Tim (Beth) Colvin, Dublin; his mother and father-in-law, Lew and Pat Colvin, Marysville; and his best friend, Tommy Guy.Funeral services will be Friday, May 5, 2017 at 11:00 AM at the First United Methodist Church, Richwood with Pastors Judy Cramer and Joe Rhea officiating. Burial will follow in Claibourne Cemetery. Friends may call on Thursday, May 4 from 2 to 8 PM at the North Union High School Gymnasium 401 N. Franklin St. Richwood, Ohio 43344.Memorial gifts may be made to NUAC, C/O Jean Smith, 23560 State Route 4, Marysville, OH 43040; Magnetic Springs United Methodist Church, 113 Olive Street, Magnetic Springs, OH 43036; and Alzheimer’s Association, 1379 Dublin Road, Columbus, OH 43215.Condolences and remembrances may be expressed at www.stofcheck-ballinger.com
About the authorFreddie TaylorShare the loveHave your say Chelsea assistant Cudicini: Carabao Cup can set up 2019by Freddie Taylor10 months agoSend to a friendShare the loveChelsea assistant Carlo Cudicini believes Carabao Cup success can help the club perform well in 2019.The Blues will take on Tottenham Hotspur in the semi-final, with the first leg to played at Wembley on Tuesday.”It’s always important to win the first trophy of the season,” he told the club’s official website . “You have the chance to win it in February and it can help to then have an even better end of the season.”As a club, we consider all the trophies to be important and we have the chance to reach the final and we obviously want to do well.”
About the authorPaul VegasShare the loveHave your say Ajax defender Blind on Chelsea defeat: It was a 0-0 gameby Paul Vegasa day agoSend to a friendShare the loveAjax defender Daley Blind says they have themselves to blame for defeat to Chelsea.Chelsea won the Champions League tie 1-0 thanks to Michy Batshuayi’s goal. “We were sloppy at times and we can blame ourselves for that, we have to improve that,” Blind told Ajax TV. “Normally we are stronger than that, but not today. We sometimes know it. If someone plays a bad ball, he does not do it on purpose. We want to do it as well as possible, but sometimes this type of competition is tough. “Then it comes to a struggle and we certainly did, we didn’t make it easy for them. They’re just a top team.”He added: “It was a 0-0 match, both teams didn’t really create great opportunities in the second half. I think that would have been more appropriate.”
Streamable/Krusty Sox SportsPaul Finebaum is in hot water over his comments earlier in the week about the Colin Kaepernick protest situation.On Monday, when the entire sports world was enveloped in debate over the 49ers quarterback’s protest of the national anthem over concerns with the oppression of African-Americans, Finebaum stated that said oppression does not exist.Awful Announcing has a clip of Finebaum’s Monday statement.On Tuesday, Finebaum doubled down during a segment of College Football Live, and got into a pretty heated debate with Joey Galloway.This morning, Finebaum went on SportsCenter with Cari Champion to apologize for his statements at length.To Finebaum’s credit, he says he spoke with Marcus Spears and Galloway about his statements, and his eyes are “wider-open” on the issues that the black community faces in America. Krusty Sox Sports has video of the segment:From Paul Finebaum’s apology:“I could spend the rest of my life trying to talk my way out of it, but I can’t. I blew it. I simply did not have a good grasp of the situation. I know better. I’ve lived in this country, I see what is going on all across the country from North to South to East to West and I have no excuse. I can’t explain why I articulated the words the way they did, but I did and there is a public record of it and there’s a natural reaction and I respect that.All I can say is that I made a terrible mistake in trying to express a feeling that I probably – not probably – I had no right to express. I don’t know whether this will mean anything to anyone but I feel compelled to answer your question that way – that it was a terrible mistake on my part and my eyes are wider-open today than they have ever been as a result.”Champion accepted his apology at the end of the segment.[Krusty Sox Sports]
Tonight’s NFC North showdown between Minnesota (2-2) and Chicago (1-3) will mark a potentially historic moment for the Bears as quarterback-of-the-future Mitch Trubisky will officially take the reins of the reeling franchise. But how much can we expect from the No. 2 overall pick in last year’s draft? Watch the video above to find out.
OSU coach Thad Matta has never started 0-4 in the Big Ten. Credit: Tino Bovenzi | For The LanternThad Matta has not been in this situation before in his 13-year tenure at Ohio State. The Buckeyes currently sit at 0-3 in the Big Ten, 10-6 overall, and in danger of falling to 0-6 in conference play with its next three games against three of teams at the top of the conference standings.However, that didn’t stop redshirt junior guard Kam Williams from entering Wednesday’s press conference laughing and joking with freshman forward Andre Wesson.“There’s a lot of season left,” Williams said. “Just because we lost three games don’t mean I’m not going to have a smile on my face. We just got to keep playing.”OSU lost one of its leaders on the court last week in junior forward Keita Bates-Diop, who underwent surgery on Tuesday for a stress fracture to his shin. At 6-foot-7 and having a wingspan of more than 7 feet, Bates-Diop was a primary influence on the glass and in post defense. On offense, he was one of the primary scoring options for the Buckeyes. He averaged 9.7 points per game this season.OSU lost a narrow game to Purdue last week at home, 76-75. Then the Buckeyes went on the road to streaking Minnesota, losing by 10. Both Purdue and Minnesota are currently ranked in the top 25.In its three conference games, OSU has allowed an average of 76.3 points per game, compared to 63 during nonconference play. OSU has relied on its defense for most of the season to get stops when the offense struggles to execute in the half court. In those three Big Ten matchups thus far, OSU has been able to do that, but that’s after the team finds itself in a double-digit hole. OSU was down 15 at Illinois, 10 to Purdue and 18 at Minnesota.OSU coach Thad Matta said the biggest thing he’s after is seeing improvement from his players in the thinking component of the game. In a way to expedite that process, Matta estimated that he has had the team work on situational execution this year more than any of his years of coaching combined.“We got to stop putting ourselves in these positions,” Matta said. “We got to find a way not to dig ourselves in that hole, if at all possible.”WisconsinThe Wisconsin Badgers, led by seniors Nigel Hayes and Bronson Koenig, and sophomore Ethan Happ host the Buckeyes in the Kohl Center at 7 p.m. on Thursday. The Badgers were looked at as a possible Final Four team in the preseason. Since then, coach Greg Gard’s team has fluttered in a few games and looked dominant in others, including wins over Indiana and Syracuse. Wisconsin currently doesn’t own a win against a top-25 team. The Badgers return all five of their starters from the 2015-16 season. Seniors Vitto Brown and Hayes are both from northwest Ohio. Wisconsin is ranked 11th in the KenPom rankings and 17th in adjusted defense with an estimated 92.8 points allowed per 100 possessions.OSU ranks 85th in adjusted offense (points per 100 possessions).Hayes was named the Big Ten’s Preseason Player of the Year, but he isn’t alone in dominating on both ends of the court. Koenig, at point guard, averages 14 points per game, while Happ, last year’s Big Ten Freshman of the Year, puts up 13.4 points and 9.1 rebounds per contest.“They got inside, outside — just a solid basketball team, just in terms of, if you make a mistake, they will make you pay with a 3,” Matta said. “Then defensively, you gotta make shots up there.”Williams is OSU’s best 3-point threat on a team that ranks 244th in the country at shooting the ball from deep. He struggled against Minnesota, shooting 1 for 10 from the field. Matta said that he is not as worried as the fan base because of the tough stretch to start the conference slate. But make no mistake about it, it’s time to go for OSU.“We know once we get locked in, and once we get engaged and start doing things with force and aggression and have that attack mentality, we’re pretty tough to stop,” Williams said. “We just got to find a way to keep that going for a full game.”