Amazing discoveries continue to pour in from Cassini, now within its second extended mission since arriving at Saturn in 2004. The spacecraft is back to nominal operations after a 3-week safing event caused by a single-bit error in the onboard computer (JPL). The recovery came just in time for another major flyby of Enceladus.Enceladus eruptions: The geysers of Enceladus continue to erupt out the south pole. The parallel cracks, dubbed “tiger stripes,” from which the eruptions occur, are longer and more complex than originally thought. This comes from new data taken November 30 during the 12th flyby at 45,000 altitude at closest approach – the last good look at the south pole in sunlight. This was E12: the twelfth targeted encounter with Enceladus. JPL and the Cassini Imaging Team released images of the bright jets shooting gas and dust outward at supersonic speeds. Particles reaching escape velocity create the E-ring around Saturn; others fall back onto the moon and brighten its surface. Live Science reminded its readers that the heat energy per unit area coming out of this small icy moon, “once thought to be cold and geologically dead,” is five times that in Yellowstone. That’s heat, of course, not temperature, since the Composite Infrared Spectrometer (CIRS) measured highest temperatures of 190 Kelvin (-120° F), cold enough to be intolerable to humans. Live Science remarked, “While that sounds cold, it is actually quite warm for this icy moon around Saturn.” Temperatures at other regions of Enceladus are typically around 80 Kelvin (-315° F) and as low as 33 K (-400° F) at the north pole. Yellowstone obviously has scalding hot temperatures localized to its geysers and hot springs, but overall, Enceladus’ geysers emit more heat energy per unit area – an astonishing discovery for a small icy moon separated from significant external heat sources. Earlier flybys had measured temperatures of 170K. Scientists are trying to understand if the new high of 190K represents increased activity along the fissure observed in the greatest detail, named Damascus Sulcus. More likely, it results from the higher resolution possible on this flyby by the CIRS instrument, allowing it to focus in on the inner regions of the channel. The observations also revealed forks at the end of two cracks where heat emission continues past the main channel, and an isolated warm spot not associated with a tiger stripe (see JPL story and image). Space.com, PhysOrg and Science Daily all reported the story.Hyperion pox: The geometry of the Enceladus flyby allowed Cassini to make another non-targeted flyby of Hyperion from about 72,000km. Since the pock-marked potato-shaped moon has a chaotic rotation, engineers cannot predict what side will face the camera. The best image was posted by JPL and SpaceRef; on YouTube, someone colorized 61 of the images and made them into a video sequence.Saturn hex: Atmospheric scientists have modeled in the lab how the mysterious hexagon at Saturn’s north pole might remain stable as a standing wave; see abstract on Icarus.1 The shape was first observed 30 years ago by the Voyagers and continues unabated to this day. “Why the jet stream takes the characteristic six-sided shape and how it is stably maintained across multiple Saturnian seasons are yet to be explained,” they said. They came up with a model and simulation that partly fits the observations; “However, our results also show that a vortex street model of the Hexagon cannot reproduce the observed propagation speed unless the zonal jet’s speed is modified beyond the uncertainties in the observed zonal wind speed, which suggests that a vortex street model of the Hexagon and the observed zonal wind profile may not be mutually compatible.” It remains a work in progress.Rhea gas: Last month Cassini scientists were surprised to find a tenuous atmosphere at Rhea composed of oxygen and carbon dioxide. Though 5 trillion times less dense than Earth’s atmosphere, it is 100 times more dense than the exospheres of Mercury and Earth’s moon, according to Science Daily. Scientists believe the oxygen comes from bombardment of the surface by Saturn’s magnetic field, causing decomposition of surface ice; “The source of the carbon dioxide is less certain.” “The new results suggest that active, complex chemistry involving oxygen may be quite common throughout the solar system and even our universe,” said lead author Ben Teolis of Southwest Research Institute; but it’s not quite clear how he connected the dots with his next statement: “Such chemistry could be a prerequisite for life.” Rhea is not exactly a lively place, as he well knows: “All evidence from Cassini indicates that Rhea is too cold and devoid of the liquid water necessary for life as we know it.” Life as we don’t know it is purely imaginary at this point.Dione donut: The Cassini site released a photo of Dione from its Oct. 17 non-targeted flyby, showing off the donut-shaped crater Erelus with a central peak 75 miles across. Cassini keeps a public diary of its activities on the Significant Events page.One of the coolest educational tools ever produced by JPL, Eyes on the Solar System was recently released by NASA. Take the Getting Started tutorials first; then, you can command your own tour of the solar system from any angle, and watch the planets and moons in motion at any speed. Current spacecraft are included, too; you can ride along with Cassini, EPOXI, MESSENGER, Rosetta, DAWN, Stardust, all the Earth orbiters, and even Voyagers 1 and 2, and see the action from their vantage points. The looks of the planets and moons and the orbits of spacecraft are all informed by actual photographs of the objects and orbital tour plans, allowing you to watch both past and future encounters. “Eyes” is the brainchild of JPL animator Kevin Hussey, a pioneer of scientific visualization, and his team, who also produced a similarly dazzling tool Eyes on the Earth 3D. Watch the Demonstration video to see all the things one can learn about our home planet.1. Morales-Juberias, Sayanagi, Dowling and Ingersoll, “Emergence of Polar-Jet Polygons from Jet Instabilities in a Saturn Model,” Icarus, article in press.Warning: Eyes on the Solar System and Eyes on the Earth 3D can be addicting! Get your kids off the blood-and-gun video games and introduce them to these real-world visualization tools. Reality can be so much more interesting than fiction. These websites have the potential to inspire the next generation of space navigators, planetary scientists and aeronautical engineers, and are fascinating interactive adventures for everyone. None of the Enceladus articles talked about how this little moon could be putting out so much energy for 4.5 billion years. That’s because they don’t have a clue. The geysers remain exciting, but not as wildly improbable, without the Law of the Misdeeds and Perversions, which cannot be altered, known as the A.S.S. 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Former Sri Lankan skipper Hashan Tillekaratne on Tuesday said he had received death threats following his revelations about match fixing in the national cricket team. Tillekaratne, now a politician in Sri Lanka’s opposition party, told media that on the advice of his lawyers he has decided against revealing specific names at this time. “I have made a statement today but I have taken advice from my lawyers and I did not expose those involved after I came out with these allegations. I have been receiving lots of nuisance calls and death threats and all these things. But I will definitely expose those involved in the time to come,” Tillekaratne said adding he has been reluctant to voice his allegations previously for fear of his safety. He also said he will tell the International Cricket Council (ICC) that cricket matches were fixed during his career. Last week Tillekaratne had said that match fixing has been prevalent in Sri Lanka since 1992 and now he reaffirmed his statement saying he would not reveal specific names. His allegations have created waves within Sri Lankan Cricket (SLC) and have been dismissed by the board as well as the current cricketers. The SLC expressed concern over the allegations and called for “concrete evidence” to substantiate them.
LOOK: Joyce Pring goes public with engagement to Juancho Triviño The 32-year-old had surgery on his ankle in November to remove a loose intra-articular body and only resumed training three weeks ago.He played the opening round at an exhibition event in Abu Dhabi last week, where he lost to South African Kevin Anderson, and gets his season proper under way in the second round of the Brisbane International on Thursday.FEATURED STORIESSPORTSPrivate companies step in to help SEA Games hostingSPORTSUrgent reply from Philippine football chiefSPORTSSEA Games: Biñan football stadium stands out in preparedness, completionThe 17-time Grand Slam winner said he hadn’t been worried about the world rankings for the past two years.“My goal is just to be happy doing what I am doing and be competitive all the weeks that I am playing,” he said. SEA Games: Biñan football stadium stands out in preparedness, completion Private companies step in to help SEA Games hosting MOST READ Spain’s Rafael Nadal reacts after he lost the semi final match to South Africa’s Kevin Anderson during the Mubadala World Tennis Championship in Abu Dhabi, United Arab Emirates, Friday, Dec. 28, 2018. (AP Photo/Kamran Jebreili)Spanish superstar Rafael Nadal insisted Tuesday he is not chasing the world’s top ranking as he prepares to make a comeback from ankle surgery, with taking care of his body a key priority.The current world number two has not played a main tour event since a knee problem forced him to retire during his US Open semi-final against Juan Martin del Potro in September.ADVERTISEMENT Sports Related Videospowered by AdSparcRead Next PH underwater hockey team aims to make waves in SEA Games PLAY LIST 02:42PH underwater hockey team aims to make waves in SEA Games01:44Philippines marks anniversary of massacre with calls for justice01:19Fire erupts in Barangay Tatalon in Quezon City01:07Trump talks impeachment while meeting NCAA athletes02:49World-class track facilities installed at NCC for SEA Games02:11Trump awards medals to Jon Voight, Alison Krauss Is Luis Manzano planning to propose to Jessy Mendiola? TS Kammuri to enter PAR possibly a day after SEA Games opening View comments SEA Games: Biñan football stadium stands out in preparedness, completion “I want to feel myself competitive every week that I am on court and I want to keep fighting for the things that really make me feel alive, you know, for the things that motivate me.“So I will not (chase) the number one because it’s not my main goal.“Of course, I prefer to be number one than number two, and I prefer to be number two than number five, that’s obvious,” he added.Nadal was forced to retire during matches at two of the four Grand Slams in 2018, but still added a record-extending 11th French Open crown to his collection.He said he wanted to ensure he could take care of his body to allow him to keep playing as long as possible because of his love for the game.ADVERTISEMENT Hotel management clarifies SEAG footballers’ kikiam breakfast issue “The thing that I don’t want to do is suffer more than what I did last year, because if you do (suffer injuries two) years in a row, that mentally kills you,” he said.“I really believe that I have to keep having tennis to play in my career, and I really feel that my body is not going to get worse every year.“Really my only goal is to keep doing the things that makes me happy, and today playing tennis makes me happy, and I want to do it the best way possible and as long as possible.”In the second round Nadal will play either Jo-Wilfried Tsonga of France or local hope Thanasi Kokkinakis, two players who have also been troubled recently by injuries. ‘Big Four’ still Grand Slam stars to beat, insists Novak Djokovic BREAKING: Corrections officer shot dead in front of Bilibid Don’t miss out on the latest news and information. LATEST STORIES