Alastair Graham Walter Cameron

first_imgAlastair Graham Walter Cameron was born in Winnipeg on June 21, 1925, and died in Tucson on October 3, 2005. As a boy his interests ran to science fiction and away from sports. His father was head of the biochemistry department at the Manitoba Medical College; at the age of four Cameron addressed all men as “Doctor,” which he later said was an early example of forming a hypothesis based on limited data.His mother raised him by herself. Working his way through a private high school he became a bookie, taking bets from fellow students, and did quite well. In about 1941 he made a bet with a classmate that man would land on the Moon by the year 1970. Years later the classmate asked Cameron how he had known when the Apollo Program would take place. He replied that he had extrapolated the speed of transportation to the time when that speed would exceed that needed to escape from the Earth.He majored in math and physics at the University of Manitoba, and for his physics Ph.D. at the University of Saskatchewan, where he devised a new method to determine nuclear cross sections. He went on to apply nuclear physics to the origin of the chemical elements, or nucleosynthesis, in stars. In 1955 he married Elizabeth “Betsy” MacMillan. Betsy called Cameron “Alastair,” but in the scientific community he was known only as “Al.”After the Ph.D., Cameron spent two years at the Ames Research Center of the U.S. Atomic Energy Commission. While there he read that the astronomer Paul Merrill had observed a feature in the spectrum of a red giant star that corresponds to the chemical element technetium (Tc). Technetium has no stable isotopes; it was discovered in 1937 only after bombarding molybdenum with energetic particles; hence its name, derived from the Greek for “artificial.” Given the fact that technetium decays rapidly into other elements, Cameron reasoned that it must have been created in the star where Merrill found it. Cameron found this discovery “very exciting” because it provides a clue to the origin of the heavy elements in the Universe. Having never studied astrophysics before, Cameron immersed himself in the literature. In 1954 he relocated to the Chalk River Laboratory of the Canadian Atomic Energy Project, where he calculated cross sections for the many nuclear reactions that occur in the interiors of stars when the temperature is high enough for collisions between charged nuclei to overcome the electrical repulsion between them.The temperature at the center of the Sun is 14 million degrees, high enough to allow the conversion of hydrogen into helium, but not high enough for the reactions that ultimately lead to the creation of elements as heavy as Tc, that require hundreds of millions of degrees.While Cameron was working on nucleosynthesis, other theorists calculated that the Sun would run out of hydrogen in 5 billion years, at which time the temperature in its core would begin to rise, and the Sun would become a red giant star of the type that Merrill observed to contain Tc. Surprisingly, when stars run out of one nuclear fuel, their cores get hotter, not cooler, and then new fuels that react only at higher temperatures kick in. In red giant stars the helium produced earlier is reacting to form even heavier elements.Cameron predicted what elements are produced and in what quantities. He found that indeed technetium is produced along the way, explaining Merrill’s observation. In order to be found in the atmospheres of the Sun and other stars, and in solid bodies such as planets and meteorites, new elements have to first be ejected from the parent star into space where they contaminate interstellar matter destined to form new generations of stars and planets. Thus the full understanding of nucleosynthesis involves the formation of stars and planets, as well as the ejection of heavy elements into space by red-giant winds and supernova explosions. Undaunted by the challenge, Cameron plunged into a full range of theoretical astrophysics.Cameron published his papers on nucleosynthesis in 1957. Experts attribute the birth of the field of nuclear astrophysics to those papers, together with one by a group at Caltech led by William Fowler published the same year. Fowler, an experimentalist, won the Nobel Prize in 1983 for his work in the field, and in his Nobel Lecture credited the independent work of Cameron.In 1961 Cameron moved from Chalk River to the newly formed Goddard Institute for Space Studies in New York City. There he supervised graduate students at Columbia, New York University, and Yale. He taught regularly at Yale, where his students compiled his notes into a monograph that is highly regarded, but unfortunately, was never published. In 1973, upon the founding of the Harvard-Smithsonian Center for Astrophysics (CfA) at 60 Garden Street, Cameron was appointed to a professorship in the Department of Astronomy at Harvard. He also accepted a position as associate director of CfA for Planetary Science, a field to which his interests were increasingly turning because of the continuing discoveries of anomalous abundances of isotopes in meteorites. His model of the Solar Nebula, a disk of gas and dust formed at the time of the origin of the Sun 4.5 billion years ago, provides quantitative temperatures that theorists use in their studies of planet formation.During this period, Cameron is reported to have given a seminar at Caltech covering the entire history of the Sun and planets, from the collapse of an interstellar cloud to the coagulation of dust to form the solid cores of the planets. When asked what he did on the seventh day, Cameron replied, “I rested.”An important result of Cameron’s work was his conclusion that the main product of the buildup of the observed high abundance of the elements near iron in the periodic table is not iron per se, as had been assumed, but radioactive nickel 56. His idea was verified many years later by a NASA spacecraft.In 1982 Cameron became the chair of the Space Science Board of the National Academy of Sciences, which advises NASA on its science program, and at Harvard he served six years as chair of the Department of Astronomy. During this period he also organized annual conferences to bring together astrophysicists and planetary scientists to enhance collaborations between their different specialties.He then decided to attack a long-standing theoretical problem in planetary physics: the origin of the Moon. The Apollo Program had found that unlike the Earth, the Moon has no iron core, but is composed solely of the same material as the mantle of the Earth. At the time theorists could not explain this fact. Cameron proposed that the Moon formed from a disk of debris orbiting the Earth, much as the Solar Nebula orbited the Sun. But where could the debris have come from? Cameron proposed that it was material ejected from Earth’s mantle when a Mars-sized body collided with the Earth early in the history of the solar system. That would explain the Moon’s composition, but how would the debris reach the distance of the Moon? Cameron attacked this problem head on, acquiring faster computers for his office in order to model the collision event. He finally succeeded in showing that such a collision would result in a disk of the correct mass, as well as the angular momenta of the Earth and Moon that are observed today. Cameron’s theory is now the accepted one for the origin of the Moon.Cameron received honors from many scientific societies, among them the Petrie Prize of the Canadian Astronomical Society, the NASA Distinguished Service Medal, the Smith Medal of the National Academy of Sciences, the Hess Medal of the American Geophysical Union, the Leonard Medal of the Meteoritical Society, the Bethe Prize of the American Physical Society, and the Henry Norris Russell Lectureship of the American Astronomical Society—the highest honor an astronomer can receive.Upon his retirement from Harvard in 1999, Cameron accepted an appointment at the Lunar and Planetary Laboratory of the University of Arizona in Tucson. There he and Betsy lived in the Academy Village, a non-profit organization devoted to life-long learning. Sadly, Betsy, his loving wife of forty-six years, died in 2001; they had no children. Those of us who were lucky enough to know Al Cameron well remember him as an exceptionally talented and dedicated scientist, a wise counselor, and a witty person. Few are those who cross one’s path with all of these qualities; Al Cameron was one of them.Respectfully submitted,Alexander DalgarnoJames MoranDimitar SasselovPatrick ThaddeusFriedrich ThielemannGerald WasserburgJohn WoodGeorge Field, Chairlast_img read more

Joleon Lescott signs for Aston Villa

first_img “I am very pleased to bring Tiago into the football club,” Sherwood told avfc.co.uk. “He’s someone I have been aware of for some time and I am looking forward to working with him. “He’s a young guy who I believe will enhance the group here.” The defender has signed a two-year deal at Villa Park after spending just over 12 months with the Baggies. Lescott passed a medical on Tuesday and the move ends a long transfer chase for Villa, who wanted to sign him before his move to Albion last summer. Press Association Lescott made 39 appearances, scoring once, for West Brom after joining from Manchester City on a free transfer last summer. But the arrival of Jonny Evans from Manchester United last week meant the Baggies were prepared to let the 33-year-old former England international leave. He was behind Gareth McAuley and Jonas Olsson but did start Saturday’s 1-0 Barclays Premier League win at Stoke. Lescott won the Barclays Premier League twice while at Manchester City, while he also helped them win the FA Cup in 2011 and League Cup last year. Villa also completed the signing of 18-year-old keeper Matija Sarkic from Anderlecht. Villa further strengthened their defensive ranks with the loan signing of Liverpool defender Tiago Ilori. The 22-year-old Portuguese, a £7million buy from Sporting Lisbon in 2013, has yet to play a first-team game for the Reds and has had loan spells at Granada and Bordeaux. Press Association Sport understands Villa will pay a loan fee of about £1million for the centre-back with the option to buy at the end of the season for a figure, depending on appearances, between £6million and £9million. Aston Villa have completed the signing of Joleon Lescott from West Brom.last_img read more

Volleyball: Badgers return to Madison in search of key win over No. 10 Penn State

first_imgAfter disappointing results in their last two performances against top 10 opponents, the University of Wisconsin volleyball team is looking to return to dominance with a marquee win over Pennsylvania State University.The Badgers got off to a 14-1 start to the season in a run that was defined by the team’s consistent success against ranked, top-tier talent. During that 15-game stretch, Wisconsin went 7-1 against top 25 teams, including wins over then-No. 2 University of Texas and then-No. 6 University of Hawaii.But the Badgers have now dropped two of their last four games, with both losses coming at the hands of No. 3 University of Minnesota and No. 1 Nebraska University. While it’s no surprise that a Big Ten schedule against the toughest volleyball conference in the country could eventually catch up with them, the Badgers suffered consecutive sweeps in their last pair of top 10 battles.Volleyball: No. 4 Badgers suffer another loss at No. 1 Nebraska, rebound 3-0 at IowaThe No. 4 University of Wisconsin women’s volleyball team had another back-and-forth weekend as they went 1-1 with a brutal Read…But this Friday, the No. 4 Badgers (16-3, 8-2 Big Ten)  have a great opportunity at home to repeat their early season success against the nation’s best as they host traditional Big Ten powerhouse No. 10 Penn State.Though the Badgers come into Friday night ranked higher than the Nittany Lions nationally, Penn State (17-4, 9-1 Big Ten) leads Wisconsin in the Big Ten standings. National champions in six of the last ten seasons, Penn State has been one of the most competitive programs in all of college volleyball during the past decade.The Badgers are more than familiar with the kind of challenge that awaits them this weekend, especially considering their recent struggles against the Nittany Lions. Wisconsin hasn’t defeated PSU since 2011 and UW has lost its previous eight meetings by 24-1 total in sets.While the No. 10 Nittany Lions started the season on a much slower note than UW, they have crept into talks of legitimate national contention once again thanks to recent 15-game winning streak.That streak came to and end last Saturday in a 3-2 road loss to the University of Michigan. The loss also marked the demise of a perfect 9-0 start to conference play. Even with the recent stumble, a statement victory over a top ten Penn State team is exactly the kind of spark that reignite the Badgers.Courtesy of Wisconsin Athletics, Friday’s game against Penn State is also Pom-Pom Giveaway night, and fans who arrive early will receive a red and white pom-pom.First serve is set for 8 p.m. Friday night in the Wisconsin Field House with live coverage airing on BTN.last_img read more

2019 Fantasy Baseball Rankings: 1B

first_imgDOMINATE YOUR DRAFT: Ultimate 2019 cheat sheetFantasy Baseball Rankings: 1B and UTILThese rankings are for standard 5×5, non-keeper leagues. Eligibility based on Yahoo default settings.* = Player not eligible at that position on draft day but expected to play there during the season** = UTIL-only eligibleRankingPlayerTeamOther eligibility1Paul GoldschmidtCardinals2Freddie FreemanBraves3Anthony RizzoCubs4Whit MerrifieldRoyals2B, OF5Cody BellingerDodgersOF6Rhys HoskinsPhilliesOF7Joey VottoReds8Jesus AguilarBrewers9Jose AbreuWhite Sox10Daniel MurphyRockies2B11Joey GalloRangersOF12Travis ShawBrewers2B, 3B13Matt CarpenterCardinals2B, 3B14Max MuncyDodgers2B, 3B15Ian DesmondRockiesOF16Edwin EncarnacionMariners17Miguel CabreraTigers18Matt OlsonA’s19Eric HosmerPadres20Robinson CanoMets2B21Justin SmoakBlue Jays22Shohei Ohtani**AngelsUTIL23Carlos SantanaIndians3B24Ryan BraunBrewersOF25C.J. CronTwins26J.T. RealmutoPhilliesC27Luke VoitYankees28Jake Lamb*Diamondbacks3B29Miguel SanoTwins3B30Ryan O’HearnRoyals31Ryan ZimmermanNationals32Jurickson ProfarA’s2B, 3B, SS33Trey ManciniOriolesOF34Ryon HealyMariners35Jake BauersIndiansOF36Peter AlonsoMets37Josh BellPirates38Kendrys MoralesBlue Jays39Yonder AlonsoWhite Sox40Tyler WhiteAstros41Ronald GuzmanRangers42Buster PoseyGiantsC43Yuli GurrielAstros2B, 3B44Wilmer FloresDiamondbacks2B, 3B45Steve PearceRed SoxOF46Brandon BeltGiants47Albert PujolsAngels48Ryan McMahonRockies2B, 3B49Niko GoodrumTigers2B, SS, 3B, OF50Enrique HernandezDodgers2B, SS, OF51Marwin GonzalezTwins2B, SS, OF52Ji-Man Choi**RaysUTIL53Jose MartinezCardinalsOF54Eric ThamesBrewersOF55MItch MorelandRed Sox56Yandy DiazRays57Jay BruceMarinersOF58Greg BirdYankees59Adam DuvallBravesOF60Matt AdamsNationals61Chris DavisOrioles62Todd Frazier*Mets3B63Justin BourAngels64Peter O’BrienMarlinsOF*65Hunter DozierRoyals3B Fantasy baseball owners usually don’t have to think much about first base. It’s always fairly deep, and the types of players you find there are generally pretty similar: Low-to-mid average, good power and run production, little speed. The guys who can hit for average or steal some bases, like Paul Goldschmidt and Freddie Freeman, are at the top, but if you don’t get one of those players, most of the “sleepers” and mid-tier players have pretty similar profiles. The 1B rankings on your cheat sheet are probably the least viewed most seasons.Watch ChangeUp, a new MLB live whip-around show on DAZN One thing that seems different this year is the amount of multi-position-eligible players. It’s not unusual for a chunk of 1Bs to also be eligible in the OF or even at 3B, but this year five of our top 15 are eligible at 2B. If you draft these players, it seems more likely you’ll wind up playing them at second base, but that extra versatility gives them more overall value. For these rankings, we’re acting as if each player is only eligible at 1B, but that doesn’t necessarily reflect the overall rankings. For instance J.T. Realmuto, who’s our No. 1 catcher is only our No. 26, ranked behind many 1Bs he’ll go ahead of in drafts. However, if he was only eligible at 1B, his .277-21-77 line from last season wouldn’t be that much better than, say, Ryon Healy’s .235-24-73 mark. 2019 Fantasy Baseball Sleepers:Catcher | First | Second | Third | Short | Outfield | Starter | Each teamThe biggest change this season at the top of the rankings is Paul Goldschmidt’s move from hitter-friendly Arizona to hitter-neutral St. Louis. The good news is he was significantly better on the road last year (.339/.415/.638 compared to .238/.363/.420), and for his career he actually has a better average (.304) and SLG (.535) away from home. The main thing to note with Goldschmidt is that he only attempted 11 steals last year, his lowest total since his 48-game rookie campaign. Don’t expect a ton of SBs from the 31-year-old free-agent-to-be.2019 Fantasy Baseball Rankings Tiers, Draft StrategyCatcher | First | Second | Third | Short | Outfield | Starter | CloserStill, we like Goldschmidt’s all-around game and upside the most, but it’s tough to nitpick between the very top options. The middle-tier is even more muddled. Health and playing time are a concern for many — and will ultimately decide what the final rankings look like. Someone like Ronald Guzman could easily finish ahead of Edwin Encarnacion at the end of the year, but it would be silly to draft them that way, even if you were really high on Guzman. If you really like him, just wait several rounds. If gets snagged in front of you, adjust your target because he’s far from the only player who could break out.2019 Fantasy Baseball Rankings:Catcher | Second | Third | Short | Outfield | Starter | Reliever | Top 300The bottom line is that there are still plenty of options at 1B, both early and late. Certain players might go earlier than expected because of their versatility, but you shouldn’t have a problem acquiring depth at this position as long as you focus on the numbers (including age and games played) and not just the names.last_img read more

COVID-19 Case Update: PBC: 2,697; Broward: 4,729; Miami: 11,351

first_imgWorldwide, the Johns Hopkins University & Medicine Coronavirus Resource Center reported 2.9 million cases and 203,622 deaths. City of West Palm Beach Launches Mobile Pop-up Testing Site According to the Florida Department of Health, there were 31,528 total cases of COVID-19 in Florida as of Sunday morning.At least 1,074 Florida residents have died from COVID-19.Palm Beach County: 2,697 cases-155 deaths-Men: 1,339, Women: 1,299-409 hospitalizationsBroward County: 4,729 cases-170 deaths-Men: 2,340, Women: 2,259-889 hospitalizationsMiami-Dade County: 11,351 cases-301 deaths-Men: 5,881, Women: 5,297-1,291 hospitalizationsThe coronavirus death toll in the United States stands at 54,001, including more than 22,000 victims in the national epicenter, New York City. The country’s total number of cases was 940,797 on Sunday morning.last_img read more

Hilleard and Petrozzi to challenge in Colombia

first_img30 Aug 2016 Hilleard and Petrozzi to challenge in Colombia  Internationals Josh Hilleard and Gian-Marco Petrozzi will represent England in this week’s Fedegolf 70 Years Cup in Colombia. The 72-hole international team championship will be played at Los Lagartos Golf Club in Bogota from September 1-4. Josh Hilleard, 21, (Farrington Park, Somerset), won the West of England Championship, the Berkhamsted Trophy, the Faldo Series Wales Championship and the Hampshire Salver in April. He was joint top-scorer when England beat France at Formby, was in England’s winning team at the Costa Ballena Quadrangular Tournament and represented England in the men’s Home Internationals. (Image © Leaderboard Photography) Gian-Marco Petrozzi, 19, (Trentham) reached the Amateur Championship matchplay and was fourth in the Brabazon Trophy, where he shot the championship low score of seven-under 65 in the final round. He tied ninth in the European amateur, third in the Duncan Putter, eighth in the Dutch Open and was 10th in the Lytham Trophy. He also represented England in the Men’s Home Internationals.last_img read more