Story Links “Now in its ninth year, the Grand Blue Mile’s national profile continues to grow and attract America’s most decorated milers,” said Blake Boldon, Franklin P. Johnson Director of the Drake Relays. “The entire Drake athletics department is proud to continue our longstanding partnership with Wellmark to bring this one-of-a-kind experience to central Iowans.” Returning to the Grand Blue Mile is the USA Track & Field Men’s and Women’s 1 Mile Road Championships. The addition of these prestigious events is expected to attract several Olympians and numerous elite athletes from across the country to vie for a national title and their share of the $30,000 prize purse. The Grand Blue Mile also hosted the 2013, 2014 and 2017 USATF 1 Mile Road Championships. Register todayRegistration is now open at grandbluemile.com. The $10 flash sales ends at 11:59 p.m., Feb. 7, after which, regularly priced registration is $15 for youth and $20 for adults. As part of Wellmark’s commitment to improving the health of Iowans, all proceeds benefit Iowa Kidstrong school fitness programs and the historic Drake Relays. Print Friendly Version Register Now “Grand Blue Mile was created to encourage sustainable healthy habits and empower positive change,” said Chris Verlengia, Wellmark Blue Cross® and Blue Shield®’s senior brand marketing manager. “The mile is an attainable goal for Iowans at all fitness levels. Whether participants walk, run or jog, the important thing is they are getting up and being active, which is an excellent start to improving the overall health of our state.” Also back by popular demand is the Mascot Madness Charity Challenge — pitting Iowa’s most beloved mascots against each other in a friendly competition as they sprint to Grand Blue Mile glory. Divided into two divisions — the fast and the furriest — the winning mascots will be awarded a $1,000 prize each for their school/organization’s charitable foundation. DES MOINES, Iowa — Registration for the ninth annual Grand Blue Mile on April 24 opened today with a $10, two-day flash sale. This deeply discounted price is available for all ages now through Feb. 7. Be part of the 109th Drake Relays by joining the thousands of runners and walkers in downtown Des Moines for the Midwest’s premier one-mile race.
After the crash of MESSENGER, magnetic fields in the solar system have become a key topic for planetary science.On April 27, David Rothery anticipated the end of the decade-long mission of MESSENGER, the second spacecraft to visit Mercury since Mariner 10 in 1974. MESSENGER stayed in orbit over the innermost planet for over a year, completing 4,104 orbits in total. In late April, mission controllers lowered its trajectory for final close-up observations before intentionally crashing the fuel-depleted craft onto the surface on April 30. Rothery, writing in The Conversation, predicted the crash would make a 15-meter-wide crater that the next spacecraft from the European Space Agency, named BepiColombo, can study in 2024.What’s now apparent is that Mercury is a misfit planet that seems not to belong where we find it. It is dense even for a rocky planet, revealing an iron-rich core that occupies more than 80% of the planet. The outer part of the core must still be molten, because this is where Mercury’s magnetic field is generated – a characteristic shared with the Earth, unlike Venus, Mars or the Moon.According to mission scientists at Johns Hopkins, that magnetic field “has been in place far longer than previously known,” data from low orbits suggest. The planet’s global magnetic field was discovered by Mariner 10 and re-measured by MESSENGER, with no significant changes in the field observable in the intervening 40 years. But only the low orbits allowed scientists to measure magnetic signals in the crustal rocks that must have been induced when the rocks were still molten. “If we didn’t have the recent very low-altitude observations, we would never have been able to discover these signals,” said Catherine Johnson. “Mercury has just been waiting to tell us its story.”Other news sources picked up the story. A press release from the University of British Columbia, Johnson’s home institution, echoed the statement that the field is between 3.7 and 3.9 billion years old. This leaves an unexplained gap of 0.6 billion years from the time of its formation, presumed to be 4.5 billion years ago. Venus, however, has none, and Mars has only patchy remnants of magnetism, if it ever had a global field. Only the Earth and Mercury among the rocky planets has a global magnetic field, and Mercury’s is much weaker than Earth’s. Our planet’s strong magnetic field protects life on the surface. Ken Croswell in Science Magazine points out the difference a habitable planet makes:Earth’s magnetic field shields us from the solar wind, but with a daytime temperature hot enough to melt lead and a night cold enough to freeze carbon dioxide gas, Mercury probably isn’t hosting any creatures that need such protection.All the sources claim as a matter of accepted fact that a dynamo in the fluid core produces the field. The original paper by Johnson et al. in Science Magazine, however, shows that things aren’t quite that simple:The simplest interpretation of the results presented here is that a core dynamo was present early in Mercury’s history. If the dynamo was thermochemically driven, this finding provides a strong constraint on models for the thermal evolution of Mercury’s interior. In particular, the existence of a core dynamo at the time of smooth plains emplacement presents a new challenge to such models. An early core dynamo can be driven by super-adiabatic cooling of the liquid core, but in typical thermal history models this phase has ended by 3.9 Ga. A later dynamo can be driven by the combined effects of cooling and compositional convection associated with formation of a solid inner core, but in most thermal history models inner core formation does not start until well after 3.7 Ga. Further progress in understanding the record of Mercury’s ancient field can also be made with improved petrological constraints on crustal compositions, information on the candidate magnetic mineralogies implied, and knowledge of their magnetic properties.There’s a conflict, in other words, between the models of how Mercury cooled over time and how the dynamo has generated a magnetic field – one that is as old as presumed, yet continues today.Earth’s MoonThe problem with magnetic fields is that they decay in strength over time, unless there is a mechanism to keep them going. That’s why dynamo theories are popular despite the problems in the models (see “What You’re Not Being Told About Earth’s Magnetic Field,” 4/17/15). Earth’s moon, 29% smaller than Mercury, also has a magnetic secret: a magnetic field bigger than Earth’s is now, if dynamo models are assumed (12/05/14). A paper in Icarus slated for publication in July 2015 calls this an unresolved problem:The source of the magnetic field recorded in the lunar crust remains an unresolved problem. The field was most likely produced by a self-sustaining dynamo in the Moon’s electrically conducting metal core, but heat flux across the core–mantle boundary was probably insufficient to power a dynamo for the field’s currently known duration from 4.2 to 3.56 Ga. Since seismic measurements indicate the existence of a solid iron inner core in addition to a still-liquid iron alloy outer core, inner core solidification and its associated thermochemically driven convection in the outer core could have been responsible for extending the dynamo’s lifetime even in the absence of superadiabatic heat flux. Here we present a coupled mantle–core thermal evolution model of the Moon and show that core solidification could explain the onset and shutoff of the lunar dynamo consistent with the global magnetic field inferred from the paleomagnetic record.It’s clear that tweaking of models is necessary to keep them in sync with age expectations, otherwise it would not still remain an unresolved problem. One thing is clear: the only rocky planet in the inner solar system that has a strong magnetic shield also has sentient beings able to think about these matters.CEH is one of the only science news sites where you can hear about the problems with current theories instead of being spoon-fed pat answers, like “simple” dynamos that supposedly keep magnetic fields going for billions of years (e.g., “Mercury’s magnetic field is almost four billion years old,” Science Daily). True science is rarely simple, especially when trying to infer conditions in the unobservable past. We think our readers need to know the real world.For more on the moon’s magnetic field specifically, see D. Russell Humphreys’ 2013 paper from the Journal of Creation posted by CMI. Humphreys has written extensively about planetary magnetic fields. He explains why dynamo models cannot work over long ages. Having updated the work of Dr. Thomas Barnes from the 1970s-1980s, he shows that the decay of the magnetic field is evidence for young ages of the Earth and other planets. CMI posted another article by Humphreys from 2008, “Mercury’s Magnetic Field Is Young.“ (Visited 170 times, 1 visits today)FacebookTwitterPinterestSave分享0 read more
“The regulations will go on the National Identification System (NIDS) project website for the public and media to provide feedback. It will then be finalised for submission to Parliament,” explained Chief Technical Director in the Office of the Prime Minister, Jacqueline Lynch-Stewart. Public comment will be invited on the regulations being developed for the National Identification and Registration Act, which was passed in Parliament last November.“The regulations will go on the National Identification System (NIDS) project website for the public and media to provide feedback. It will then be finalised for submission to Parliament,” explained Chief Technical Director in the Office of the Prime Minister, Jacqueline Lynch-Stewart.She was addressing a recent Think Tank at the JIS head office in Kingston.Mrs. Lynch Stewart noted that the regulations, which will underpin the governance framework for NIDS, are being developed through a multisectoral working group, which includes representatives from the church, civil society, and the public and private sectors.She indicated that the regulation to guide enrolment for NIDS will be uploaded for feedback in short order.Mrs. Lynch-Stewart, in the meanwhile, said the project team is utilising research and international best practices in the implementation of the NIDS project.“In putting in the system, we are making sure that we are using international best practices for everything. So we have done a tremendous amount of research in relation to the countries that have introduced a national ID system. We are learning from the errors and successes of other countries,” she told JIS News.The pilot for the NIDS will be rolled out in January 2019, starting with public-sector workers.Mrs. Lynch-Stewart said a community will also be selected for roll-out of the pilot.“We haven’t taken a decision as to which community will participate in the pilot [as yet], but this is so we can get a feel of how the system functions and learn from it, so that when we reach to the national roll-out, we would have had some experience as to what worked and what didn’t,” she said.Mrs. Lynch-Stewart said it will take approximately three years to complete enrolment of at least 80 per cent of the population.“It is important that Jamaica understands that this is not an overnight thing, and we are doing it in a methodical way, in a structured way, because we need to make sure it’s done right,” she said.She further noted that there will be a transitional period during which the older means of identification will be accepted as well as the national ID.“When we reach that tipping point of most of us registered, then the Prime Minister will take a decision that as of a specific date, the national ID will be required,” she said. Public comment will be invited on the regulations being developed for the National Identification and Registration Act, which was passed in Parliament last November. She was addressing a recent Think Tank at the JIS head office in Kingston. Story Highlights read more