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Rare Moments of Glory: Planetary Scientists Admit Seeing “Lucky” Circumstances

first_img(Visited 37 times, 1 visits today)FacebookTwitterPinterestSave分享0 Why are we seeing young phenomena in the planets if they are billions of years old?  Some scientists are abandoning uniformitarian assumptions and admitting we are lucky to be witnessing them in “rare moments of glory.”In Nature this week, Maggie McKee interviewed scientists who are struggling with short-lived phenomena in the solar system.  The subtitle of her article, “Caught in the Act,” states, “We may be seeing some of the Solar System’s most striking objects during rare moments of glory.”  Her first two paragraphs elaborate why this is unsettling for some:Ever since Copernicus evicted Earth from its privileged spot at the centre of the Solar System, researchers have embraced the idea that there is nothing special about our time and place in the Universe. What observers see now, they presume, has been going on for billions of years — and will continue for eons to come.But observations of the distant reaches of the Solar System made in the past few years are challenging that concept. The most active bodies out there — Jupiter’s moon Io and Saturn’s moons Enceladus and Titan — may be putting on limited-run shows that humans are lucky to witness. Saturn’s brilliant rings, too, might have appeared relatively recently, and could grow dingy over time. Some such proposals make planetary researchers uncomfortable, because it is statistically unlikely that humans would catch any one object engaged in unusual activity — let alone several.It seems a bitter pill for some planetary scientists to “go against the grain of one of geology’s founding principles: uniformitarianism, which states that planets are shaped by gradual, ongoing processes,” she wrote.  Then she quoted Jeff More (NASA-Ames) who explained that “Geologists like things to be the same as they ever were” because it’s “philosophically comforting because you don’t have to assume you’re living in special times.”  Why that should be “comforting” was not explained.McKee zoomed into each of these phenomena for more detail about what makes them look young:Saturn’s rings:  The rings are 90% water ice but should be dirtier if they were old; “some planetary scientists say that the rings’ resplendence is hard to reconcile with a lifetime lasting billions of years.”  That’s why hypotheses of a recent encounter with an icy interloper that broke apart and became the rings within the last few million years (just 10% of Saturn’s assumed age) have been put forth.  An ad hoc solution like that, though raises other problems: all such candidate objects should have vanished 700 million years after the birth of the solar system, according to current theory.  Close flybys by Cassini in years to come may confirm whether billions of years of dirt is hiding in the B ring, McKee said, but one responded, “if the Cassini results point to a low mass for the rings, it will be a real mystery.”  This explanation, however, fails to explain why the thinner D, C, A, F, G, and E rings are so bright.Enceladus:  The geysers of Enceladus are another thing that can’t be old; “researchers have struggled to explain how it can sustain such activity” on the order of 16 gigawatts – 10 times the amount they can account for by internal radioactive heating.  “Several explanations have been put forward to account for this furious release of heat, but all rely on arguments that researchers are viewing the moon at a special time,” McKee said.  It’s difficult to keep the geysers going for 10 million years (1/450th the assumed age of the moon), let alone 4.5 billion.  One researcher who proposed a recent cracking from growing stresses in the crust has apparently been getting hard questions: “‘It seems like special pleading — we just happened to catch it in the act,’ says [Craig] O’Neill [Macquarie University, Sydney], echoing criticisms that he has heard when presenting the model at conferences.”  Nearby Mimas “should be producing more heat than Enceladus and it doesn’t, and we don’t really understand why,” O’Neill said.Io:  If Enceladus is a firefly, Io is a furnace, McKee wrote.  It gives off 90,000 gigawatts through its incessant volcanoes, “several times more than would be expected from the simplest models of tidal interactions between the moon and Jupiter.”  Again, it’s not that planetary scientists are unable to imagine scenarios in which we might be seeing Io at a special time; perhaps the moon’s orbital dance with the other moons makes it undergo periodic exaggerations of its eccentricity.  Even though this “would satisfy the data,” one planetologist said, when thinking about the peculiarities of Io and Enceladus, “it’s possible we simply don’t understand them.“Titan:  The largest moon of Saturn presents problems with both its atmosphere and surface.  Atmospheric theories are up in the air, because “the atmospheric methane — and its effects on the landscape — ought to be short-lived” in the range of a few tens of millions of years.  If sources of replenishment cannot be found (there are some disputed candidates thought to be ice volcanoes), it should have been long gone.  Jeff Moore “thinks that researchers are seeing Titan at a unique and geologically fleeting time.”  The question then becomes, why now, and what happened?  In Moore’s hypothesis, the sun warmed up to a tipping point a few tens or hundreds of millions of years ago, levitating the frozen nitrogen and methane into an atmosphere that “rained like hell” onto the surface, creating the erosional features seen today.  Ralph Lorenz [Johns Hopkins U] criticizes Moore’s view as “too simplistic” and pointed to “some evidence” (not mentioned in the article) that it would have taken billions of years to form Titan’s hydrocarbon-rich sand dunes.McKee ended with a quote from Lorenz: “I think we have to have a much more nuanced view of Titan through time.  Titan is bloody complicated.”It’s not complicated at all, if you subtract out the needless billions of years.  This article is important, in that in the 8 years of the ongoing Cassini mission to Cassini, and the 9 years since the end of the Galileo mission to Jupiter, scientists still have no answers to these age conundrums.  Their uniformitarian philosophy makes them uncomfortable with the facts their own eyes are beholding.  We should not be living in special times, but we appear to. (Understand that the Copernican principle does not mean that we are not special; see The Privileged Planet for corrective information.)Here’s a classic case of ad hoc explanation to force observations into a web of belief.  (This is called ‘special pleading’ in logic.)  If science were about honestly following the evidence where it leads, these scientists would have to conclude that the solar system is much younger than thought.  But they won’t do it, because they know Charlie D. (their idol) needs billions of years for life to evolve on Earth.  Failing to provide those annual sacrifices to the idol would get them excommunicated from the Church of Darwin.If Saturn’s rings, Enceladus, Io and Titan were the only problem worlds, they might have hope to rescue their beliefs someday.  Unfortunately, the problems mount for uniformitarianism when one considers Mercury, Venus, Earth, the Moon, Mars, Jupiter and its moons, Uranus and its moons and rings, Neptune and its moons and rings, Pluto and the trans-Neptunian objects, comets, asteroids, dust – the whole system.  There is hardly any planet or moon that met their uniformitarian expectations.  We call on them: please, dump the assumption of billions of years, and all these things will start making sense.  We do this out of sympathy for their discomfort, wishing them to sleep well for once.last_img read more

Amid contrasting claims, J&K Governor dissolves Assembly

first_img Senior PDP leader Naeem Akhtar said the BJP-backed PC claim only hinted at “illegitimate means the two parties were planning to employ in J&K to cobble together the required numbers.”“Initially, the BJP claimed an alliance of the NC, PDP and Congress was on the directions of Pakistan. It was bizarre. The BJP’s bid to project the head of a two-MLA party as new chief minister only showed the party’s desperation and illegal design to break parties here. Unfortunately, the BJP was supporting a leader who started his political career with a gun in his hand against the state of India and whose family still preaches separatism. And they call it nationalism,” said Mr. Akhtar.Undemocratic, says SozSenior Congress leader Saifuddin Soz termed the Governor’s decision “unconstitutional and undemocratic.”“Ms. Mufti should approach the court as the Governor dissolved the Assembly at the behest of the Centre,” said Mr. Soz.Earlier, in an eventful day, arch rivals, the National Conference and the PDP, decided to join hands to form a unity government, with the Congress openly offering its support.“The move was made with the sole aim of safeguarding the special status of J&K, which is under threat,” said PDP leader Altaf Bukhari.Ms. Mufti said the move was also necessitated because “the Governor’s administration randomly was amending the laws concerning the special status of the State and the BJP had started engineering defections in other parties for furtherance of its political motives.”“Governor Malik’s [earlier] decision not to dissolve the Assembly till 2020 kept the options of horse trading open. It was a serious situation,” said Congress president G.A. Mir.The sudden decision to form the government came just a day after a senior PDP leader and MP Muzaffar Hussain Baigh publicly supported Mr. Lone and the BJP-backed third front, triggering hectic political parleys among the three parties.“The BJP had started engineering defections in other parties for furtherance of its political motives. The three parties came together to stop horse trading too,” said Ms. Mufti.PDP’s Bukhari is emerging as a consensus candidate to lead the alliance as of now.Senior BJP leader Kavinder Gupta said these parties were worried because their ground was slipping in the State, as reflected in the recent elections.“This alliance is coming together on the directions of Pakistan. Meetings were happening in Dubai too. Even the Hurriyat is onboard for this,” said Mr. Gupta. Jammu and Kashmir Governor Satya Pal Malik on Wednesday dissolved the State Assembly, as Peoples Democratic Party (PDP) and Peoples Conference (PC) separately staked claim to form a government after day-long political drama.“Governor Malik has passed an order in exercise of the powers conferred upon him by clause (b) of subsection (2) of Section 53 of the Constitution of Jammu and Kashmir to dissolve the Legislative Assembly,” read a Raj Bhavan communique.Earlier, two parties, the PDP and the PC, after daylong political wrangling, wrote to the Raj Bhavan on email and WhatsApp to stake claim to form the government, as the Governor’s official fax failed to respond.Former Chief Minister and PDP president Mehbooba Mufti, in the letter, claimed that she had the support of 15 MLAs from National Conference and 12 MLAs of the Congress, in addition to her 29 MLAs, putting the total number at 56.The Assembly has 87 members and any party would require 44 MLAs’ support to form a government.On the other hand, PC chief Sajad Lone, who has two MLAs, claimed the support of 25 MLAs of the BJP and 18 more MLAs.National Conference leader and former Chief Minister Omar Abdullah cried foul over the Governor’s decision. “The NC has been pressing for Assembly dissolution for five months now. It can’t be a coincidence that within minutes of Mehbooba Mufti Sahiba’s letter staking claim the order to dissolve the Assembly suddenly appears,” said Mr. Abdullah.Also Read J&K Assembly dissolved: as it happened last_img read more

South Africa name first Test line-up

first_imgSouth Africa have left out off-spinner Johan Botha, left-arm seamer Wayne Parnell and middle-order batsman JP Duminy from their Test line-up for the first match of the high-profile series against India starting at Centurion on December 16.Captain Graeme Smith and key batsman Hashim Amla, both of whom recovering from injuries, were expectedly named in the 12-man line-up.Botha, Parnell and Duminy were part of the original 15-man squad and they have now been released to represent their respective domestic teams in the latest round of the Supersport series that begins on Thursday.Parnell and Botha will play for the Warriors, and Duminy for the Cobras.The decision means that there will be a toss up between Ryan McLaren and Lonwabo Tsotsobe for the third seamer’s slot, while Paul Harris is a certainty in the playing XI if South Africa opt for a spinner. Duminy’s exclusion ensures Ashwell Prince will keep the number six slot.South Africa squad for first Test:Graeme Smith (capt), AB de Villiers, Jacques Kallis, Ashwell Prince, Dale Steyn, Morne Morkel, Mark Boucher (wk), Lonwabo Tsotsobe, Ryan McLaren, Paul Harris, Hashim Amla, Alviro Petersen.last_img read more