Tour De Murrieta Race Report 35+Michael JohnsonMonster Media RacingThree days of tough, challenging, gritty racing at the Tour De Murrieta in Southern California. This is what Monster Media Racing is all about. The TDM is one of several key stage races this season for our team. Our mission is simple: race together as a unified team, race hard, go for the win, have fun, and help raise awareness in the fight against mesothelioma, a rare cancer caused by asbestos.We started our campaign last year by sponsoring the “John Johnson Pro Men’s Criterium” at at the prestigious Dana Point Grand Prix, a race we named after my Dad, who passed away from mesothelioma. We will sponsor the same race again this year. I’m very happy that Monster …Read more
After searching hundreds of millions of objects across our sky, NASA’s Wide-Field Infrared Survey Explorer (WISE) has turned up no evidence of the hypothesized celestial body in our solar system commonly dubbed “Planet X.”Researchers previously had theorized about the existence of this large, but unseen celestial body, suspected to lie somewhere beyond the orbit of Pluto. In addition to “Planet X,” the body had garnered other nicknames, including “Nemesis” and “Tyche.”This recent study, which involved an examination of WISE data covering the entire sky in infrared light, found no object the size of Saturn or larger exists out to a distance of 10,000 astronomical units (au), and no object larger than Jupiter exists out to 26,000 au. One astronomical unit equals 93 million miles. Earth is 1 au, and Pluto about 40 au, from the sun.”The outer solar system probably does not contain a large gas giant planet, or a small, companion star,” said Kevin Luhman of the Center for Exoplanets and Habitable Worlds at Penn State University, University Park, Pa., author of a paper in the Astrophysical Journal describing the results.But searches of the WISE catalog are not coming up empty. A second study reveals several thousand new residents in our sun’s “backyard,” consisting of stars and cool bodies called brown dwarfs.”Neighboring star systems that have been hiding in plain sight just jump out in the WISE data,” said Ned Wright of the University of California, Los Angeles, the principal investigator of the mission.The second WISE study, which concentrated on objects beyond our solar system, found 3,525 stars and brown dwarfs within 500 light-years of our sun.”We’re finding objects that were totally overlooked before,” said Davy Kirkpatrick of NASA’s Infrared and Processing Analysis Center at the California Institute of Technology, Pasadena, Calif. Kirkpatrick is lead author of the second paper, also in the Astrophysical Journal. Some of these 3,525 objects also were found in the Luhman study, which catalogued 762 objects.The WISE mission operated from 2010 through early 2011, during which time it performed two full scans of the sky — with essentially a six-month gap between scans. The survey captured images of nearly 750 million asteroids, stars and galaxies. In November 2013, NASA released data from the AllWISE program, which now enables astronomers to compare the two full-sky surveys to look for moving objects.In general, the more an object in the WISE images appears to move over time, the closer it is. This visual clue is the same effect at work when one observes a plane flying low to the ground versus the same plane flying at higher altitude. …Read more
Oct. 21, 2013 — The gauzy rings of Saturn and the dark side of the planet glow in newly released infrared images obtained by NASA’s Cassini spacecraft.”Looking at the Saturn system when it is backlit by the sun gives scientists a kind of inside-out view of Saturn that we don’t normally see,” said Matt Hedman, a participating scientist based at the University of Idaho, Moscow, Idaho. “The parts of Saturn’s rings that are bright when you look at them from backyard telescopes on Earth are dark, and other parts that are typically dark glow brightly in this view.”It can be difficult for scientists to get a good look at the faint outer F, E and G rings, or the tenuous inner ring known as the D ring when light is shining directly on them. That’s because they are almost transparent and composed of small particles that do not reflect light well. What’s different about this viewing geometry?When these small particles are lit from behind, they show up like fog in the headlights of an oncoming vehicle. The C ring also appears relatively bright here; not because it is made of dust, but because the material in it — mostly dirty water ice — is translucent. In fact, in the 18th and 19th centuries, it was known as the “crepe ring” because of its supposed similarity to crepe paper. The wide, middle ring known as the B ring — one of the easiest to see from Earth through telescopes because it is densely packed with chunks of bright water ice — looks dark in these images because it is so thick that it blocks almost all of the sunlight shining behind it. Infrared images also show thermal, or heat, radiation. While a visible-light image from this vantage point would simply show the face of the planet as dimly lit by sunlight reflected off the rings, Saturn glows brightly in this view because of heat from Saturn’s interior.In a second version of the image, scientists “stretched” or exaggerated the contrast of the data, which brings out subtleties not initially visible.Structures in the wispy E ring — made from the icy breath of the moon Enceladus — reveal themselves in this exaggerated view. …Read more
Photo courtesy of Lasala Images Racing a bike hard won’t cure cancer. Racing a bike really hard and even winning won’t cure it either. So what’s the point? Why am I so proud and privileged to have won the gold medal with my friend and teammate Michael Johnson in the Masters National Championships tandem time trial last week in Prineville, Oregon?I’ll tell you why.Michael – MJ – and I have a bond. It’s not a bond we wanted, because it came about only through unspeakably sad and wrenching loss. MJ lost his father, John Johnson, in 2012. I lost my father, David “Punch”Worthington, in 2006. Both were taken from us well before their prime. These two strong and swarthy former U.S. Marines were taken by cancers…Read more
Aug. 29, 2013 — Astronomers using NASA’s Chandra X-ray Observatory have taken a major step in explaining why material around the giant black hole at the center of the Milky Way Galaxy is extraordinarily faint in X-rays. This discovery holds important implications for understanding black holes.New Chandra images of Sagittarius A* (Sgr A*), which is located about 26,000 light-years from Earth, indicate that less than 1 percent of the gas initially within Sgr A*’s gravitational grasp ever reaches the point of no return, also called the event horizon. Instead, much of the gas is ejected before it gets near the event horizon and has a chance to brighten, leading to feeble X-ray emissions.These new findings are the result of one of the longest observation campaigns ever performed with Chandra. The spacecraft collected five weeks’ worth of data on Sgr A* in 2012. The researchers used this observation period to capture unusually detailed and sensitive X-ray images and energy signatures of super-heated gas swirling around Sgr A*, whose mass is about 4 million times that of the sun.”We think most large galaxies have a supermassive black hole at their center, but they are too far away for us to study how matter flows near it,” said Q. Daniel Wang of the University of Massachusetts in Amherst, who led of a study published Thursday in the journal Science. “Sgr A* is one of very few black holes close enough for us to actually witness this process.”The researchers found that the Chandra data from Sgr A* did not support theoretical models in which the X-rays are emitted from a concentration of smaller stars around the black hole. Instead, the X-ray data show the gas near the black hole likely originates from winds produced by a disk-shaped distribution of young massive stars.”This new Chandra image is one of the coolest I’ve ever seen,” said co-author Sera Markoff of the University of Amsterdam in the Netherlands. “We’re watching Sgr A* capture hot gas ejected by nearby stars, and funnel it in towards its event horizon.”To plunge over the event horizon, material captured by a black hole must lose heat and momentum. …Read more
Aug. 7, 2013 — One of the world’s longest migrations of zebras occurs in the African nation of Botswana, but predicting when and where zebras will move has not been possible until now. Using NASA rain and vegetation data, researchers can track when and where arid lands begin to green, and for the first time anticipate if zebras will make the trek or, if the animals find poor conditions en route, understand why they will turn back.Covering an area of approximately 8,500 square miles (22,000 square kilometers), Botswana’s Okavango Delta is one end of the second-longest zebra migration on Earth, a 360-mile (580-kilometer) round trip to the Makgadikgadi Salt Pans — the largest salt pan system on the planet. Zebras walk an unmarked route that takes them to the next best place for grazing, while overhead thundering cloudbursts of late October rains drive new plant growth, filling pockmarks across this largest inland delta in the world. In a matter of weeks, the flooded landscape could yield ecosystems flush with forage for the muscled movers.High above, Earth-orbiting satellites capture images of the zebras’ movements on this epic trek, as well as the daily change in environmental conditions. Zebras don’t need data to know when it’s time to find better forage: The surge of rain-coaxed grasses greening is their prompt to depart. But now, researchers are able to take that data and predict when the zebras will move.Pieter Beck, research associate with the Woods Hole Research Center in Falmouth, Mass., and three collaborators studied animal migration in a novel way, which they described in a paper published in the Journal of Geophysical Research–Biogeoscences, a publication of the American Geophysical Union. While tracking animal movement with satellites has been accomplished many times, Beck said, he and his team combined that information with in-depth use of environmental satellite data, using a series of images of vegetation growth and rainfall taken over days and weeks. This sheds unprecedented light on what drives animals to migrate, he said, what cues they use, and how animal migrations respond to environmental change.Zebra mind: A band of scientists earn their stripesThe Zebra Migration Research Project began in 2008 after Hattie Bartlam-Brooks and her team discovered the migration during field work for Okavango Herbivore Research. Anecdotal evidence — unverified stories — prior to the 1970s described a zebra migration from the Okavango Delta to the Makgadikgadi Salt Pans at the start of the rainy season in September and continuing through April, but from 1968 to 2004, veterinary fences prevented zebras from making the migration. …Read more
July 31, 2013 — The intensity of the jets of water ice and organic particles that shoot out from Saturn’s moon Enceladus depends on the moon’s proximity to the ringed planet, according to data obtained by NASA’s Cassini spacecraft.The finding adds to evidence that a liquid water reservoir or ocean lurks under the icy surface of the moon. This is the first clear observation the bright plume emanating from Enceladus’ south pole varies predictably. The findings are detailed in a scientific paper in this week’s edition of Nature.”The jets of Enceladus apparently work like adjustable garden hose nozzles,” said Matt Hedman, the paper’s lead author and a Cassini team scientist based at Cornell University in Ithaca, N.Y. “The nozzles are almost closed when Enceladus is closer to Saturn and are most open when the moon is farthest away. We think this has to do with how Saturn squeezes and releases the moon with its gravity.”Cassini, which has been orbiting Saturn since 2004, discovered the jets that form the plume in 2005. The water ice and organic particles spray out from several narrow fissures nicknamed “tiger stripes.””The way the jets react so responsively to changing stresses on Enceladus suggests they have their origins in a large body of liquid water,” said Christophe Sotin, a co-author and Cassini team member at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Liquid water was key to the development of life on Earth, so these discoveries whet the appetite to know whether life exists everywhere water is present.”For years scientists hypothesized the intensity of the jets likely varied over time, but no one had been able to show they changed in a recognizable pattern. Hedman and colleagues were able to see the changes by examining infrared data of the plume as a whole, obtained by Cassini’s visual and infrared mapping spectrometer (VIMS), and looking at data gathered over a long period of time.The VIMS instrument, which enables the analysis of a wide range of data including the hydrocarbon composition of the surface of another Saturnian moon, Titan, and the seismological signs of Saturn’s vibrations in its rings, collected more than 200 images of the Enceladus plume from 2005 to 2012.These data show the plume was dimmest when the moon was at the closest point in its orbit to Saturn. The plume gradually brightened until Enceladus was at the most distant point, where it was three to four times brighter than the dimmest detection. This is comparable to moving from a dim hallway into a brightly lit office.Adding the brightness data to previous models of how Saturn squeezes Enceladus, the scientists deduced the stronger gravitational squeeze near the planet reduces the opening of the tiger stripes and the amount of material spraying out. …Read more
July 17, 2013 — There is only one planet we know of, so far, that is drenched with life. That planet is Earth, as you may have guessed, and it has all the right conditions for critters to thrive on its surface. Do other planets beyond our solar system, called exoplanets, also host life forms?Astronomers still don’t know the answer, but they search for potentially habitable planets using a handful of criteria. Ideally, they want to find planets just like Earth, since we know without a doubt that life took root here. The hunt is on for planets about the size of Earth that orbit at just the right distance from their star — in a region termed the habitable zone.NASA’s Kepler mission is helping scientists in the quest to find these worlds, sometimes called Goldilocks planets after the fairy tale because they orbit where conditions are “just right” for life. Kepler and other telescopes have confirmed a handful so far, all of which are a bit larger than Earth — the Super Earths. The search for Earth’s twin, a habitable-zone planet as small as Earth, is ongoing.An important part of this research is the continuing investigation into exactly where a star’s habitable zone starts and stops.The habitable zone is the belt around a star where temperatures are ideal for liquid water — an essential ingredient for life as we know it — to pool on a planet’s surface. Earth lies within the habitable zone of our star, the sun. Beyond this zone, a planet would probably be too cold and frozen for life (though it’s possible life could be buried underneath a moon’s surface). A planet lying between a star and the habitable zone would likely be too hot and steamy.That perfect Goldilocks planet within the zone wouldn’t necessarily be home to any furry creatures. …Read more
July 10, 2013 — NASA’s Interstellar Boundary Explorer (IBEX) spacecraft recently provided the first complete pictures of the solar system’s downwind region, revealing a unique and unexpected structure.Researchers have long theorized that, like a comet, a “tail” trails the heliosphere, the giant bubble in which our solar system resides, as the heliosphere moves through interstellar space. The first IBEX images released in 2009 showed an unexpected ribbon of surprisingly high energetic neutral atom (ENA) emissions circling the upwind side of the solar system. With the collection of additional ENAs over the first year of observations, a structure dominated by lower energy ENAs emerged, which was preliminarily identified as the heliotail. However, it was quite small and appeared to be offset from the downwind direction, possibly because of interactions from the galaxy’s external magnetic field.As the next two years of IBEX data filled in the observational hole in the downwind direction, researchers found a second tail region to the side of the previously identified one. The IBEX team reoriented the IBEX maps and two similar, low-energy ENA structures became clearly visible straddling the downwind direction of the heliosphere, indicating structures that better resemble “lobes” than a single unified tail.”We chose the term ‘lobes’ very carefully,” says Dr. Dave McComas, IBEX principal investigator and assistant vice president of the Space Science and Engineering Division at Southwest Research Institute. “It may well be that these are separate structures bent back toward the downwind direction. However, we can’t say that for certain with the data we have today.”The team adopted the nautical terms port and starboard to distinguish the lobes, as the heliosphere is the “vessel” that transports our solar system throughout the galaxy.IBEX data show the heliotail is the region where the Sun’s million mile per hour solar wind flows down and ultimately escapes the heliosphere, slowly evaporating because of charge exchange. The slow solar wind heads down the tail in the port and starboard lobes at low- and mid-latitudes and, at least around the Sun’s minimum in solar activity, fast solar wind flows down it at high northern and southern latitudes.”We’re seeing a heliotail that’s much flatter and broader than expected, with a slight tilt,” says McComas. “Imagine sitting on a beach ball. …Read more
July 1, 2013 — A new study that calculates the influence of cloud behavior on climate doubles the number of potentially habitable planets orbiting red dwarfs, the most common type of stars in the universe. This finding means that in the Milky Way galaxy alone, 60 billion planets may be orbiting red dwarf stars in the habitable zone.Researchers at the University of Chicago and Northwestern University based their study, which appears in Astrophysical Journal Letters, on rigorous computer simulations of cloud behavior on alien planets. This cloud behavior dramatically expanded the habitable zone of red dwarfs, which are much smaller and fainter than stars like the sun.Current data from NASA’s Kepler Mission, a space observatory searching for Earth-like planets orbiting other stars, suggest there is approximately one Earth-size planet in the habitable zone of each red dwarf. The UChicago-Northwestern study now doubles that number.”Most of the planets in the Milky Way orbit red dwarfs,” said Nicolas Cowan, a postdoctoral fellow at Northwestern’s Center for Interdisciplinary Exploration and Research in Astrophysics. “A thermostat that makes such planets more clement means we don’t have to look as far to find a habitable planet.”Cowan is one of three co-authors of the study, as are UChicago’s Dorian Abbot and Jun Yang. The trio also provide astronomers with a means of verifying their conclusions with the James Webb Space Telescope, scheduled for launch in 2018.The formula for calculating the habitable zone of alien planets — where they can orbit their star while still maintaining liquid water at their surface — has remained much the same for decades. But the formula largely neglects clouds, which exert a major climatic influence.”Clouds cause warming, and they cause cooling on Earth,” said Abbot, an assistant professor in geophysical sciences at UChicago. “They reflect sunlight to cool things off, and they absorb infrared radiation from the surface to make a greenhouse effect. That’s part of what keeps the planet warm enough to sustain life.”A planet orbiting a star like the sun would have to complete an orbit approximately once a year to be far enough away to maintain water on its surface. “If you’re orbiting around a low mass or dwarf star, you have to orbit about once a month, once every two months to receive the same amount of sunlight that we receive from the sun,” Cowan said.Tightly orbiting planetsPlanets in such a tight orbit would eventually become tidally locked with their sun. …Read more
June 6, 2013 — Stars have an alluring pull on planets, especially those in a class called hot Jupiters, which are gas giants that form farther from their stars before migrating inward and heating up.Now, a new study using data from NASA’s Kepler Space Telescope shows that hot Jupiters, despite their close-in orbits, are not regularly consumed by their stars. Instead, the planets remain in fairly stable orbits for billions of years, until the day comes when they may ultimately get eaten.”Eventually, all hot Jupiters get closer and closer to their stars, but in this study we are showing that this process stops before the stars get too close,” said Peter Plavchan of NASA’s Exoplanet Science Institute at the California Institute of Technology, Pasadena, Calif. “The planets mostly stabilize once their orbits become circular, whipping around their stars every few days.”The study, published recently in the Astrophysical Journal, is the first to demonstrate how the hot Jupiter planets halt their inward march on stars. Gravitational, or tidal, forces of a star circularize and stabilize a planet’s orbit; when its orbit finally become circular, the migration ceases.”When only a few hot Jupiters were known, several models could explain the observations,” said Jack Lissauer, a Kepler scientist at NASA’s Ames Research Center, Moffet Field, Calif., not affiliated with the study. “But finding trends in populations of these planets shows that tides, in combination with gravitational forces by often unseen planetary and stellar companions, can bring these giant planets close to their host stars.”Hot Jupiters are giant balls of gas that resemble Jupiter in mass and composition. They don’t begin life under the glare of a sun, but form in the chilly outer reaches, as Jupiter did in our solar system. Ultimately, the hot Jupiter planets head in toward their stars, a relatively rare process still poorly understood.The new study answers questions about the end of the hot Jupiters’ travels, revealing what put the brakes on their migration. Previously, there were a handful of theories explaining how this might occur. One theory proposed that the star’s magnetic field prevented the planets from going any farther. When a star is young, a planet-forming disk of material surrounds it. …Read more
May 30, 2013 — Measurements taken by NASA’s Mars Science Laboratory mission as it delivered the Curiosity rover to Mars in 2012 are providing NASA the information it needs to design systems to protect human explorers from radiation exposure on deep-space expeditions in the future.
Curiosity’s Radiation Assessment Detector (RAD) is the first instrument to measure the radiation environment during a Mars cruise mission from inside a spacecraft that is similar to potential human exploration spacecraft. The findings reduce uncertainty about the effectiveness of radiation shielding and provide vital information to space mission designers who will need to build in protection for spacecraft occupants in the future.
“As this nation strives to reach an asteroid and Mars in our lifetimes, we’re working to solve every puzzle nature poses to keep astronauts safe so they can explore the unknown and return home,” said William Gerstenmaier, NASA’s associate administrator for human exploration and operations in Washington. “We learn more about the human body’s ability to adapt to space every day aboard the International Space Station. As we build the Orion spacecraft and Space Launch System rocket to carry and shelter us in deep space, we’ll continue to make the advances we need in life sciences to reduce risks for our explorers. Curiosity’s RAD instrument is giving us critical data we need so that we humans, like the rover, can dare mighty things to reach the Red Planet.”
The findings, which are published in the May 31 edition of the journal Science, indicate radiation exposure for human explorers could exceed NASA’s career limit for astronauts if current propulsion systems are used.
Two forms of radiation pose potential health risks to astronauts in deep space. One is galactic cosmic rays (GCRs), particles caused by supernova explosions and other high-energy events outside the solar system. The other is solar energetic particles (SEPs) associated with solar flares and coronal mass ejections from the sun.
Radiation exposure is measured in units of Sievert (Sv) or milliSievert (one one-thousandth Sv). Long-term population studies have shown exposure to radiation increases a person’s lifetime cancer risk. Exposure to a dose of 1 Sv, accumulated over time, is associated with a five percent increase in risk for developing fatal cancer.
NASA has established a three percent increased risk of fatal cancer as an acceptable career limit for its astronauts currently operating in low-Earth orbit. The RAD data showed the Curiosity rover was exposed to an average of 1.8 milliSieverts of GCR per day on its journey to Mars. Only about three percent of the radiation dose was associated with solar particles because of a relatively quiet solar cycle and the shielding provided by the spacecraft.
The RAD data will help inform current discussions in the United States’ medical community, which is working to establish exposure limits for deep-space explorers in the future.
“In terms of accumulated dose, it’s like getting a whole-body CT scan once every five or six days,” said Cary Zeitlin, a principal scientist at the Southwest Research Institute (SwRI) in San Antonio and lead author of the paper on the findings. “Understanding the radiation environment inside a spacecraft carrying humans to Mars or other deep space destinations is critical for planning future crewed missions.”
Current spacecraft shield much more effectively against SEPs than GCRs. To protect against the comparatively low energy of typical SEPs, astronauts might need to move into havens with extra shielding on a spacecraft or on the Martian surface, or employ other countermeasures. GCRs tend to be highly energetic, highly penetrating particles that are not stopped by the modest shielding provided by a typical spacecraft.
“Scientists need to validate theories and models with actual measurements, which RAD is now providing,” said Donald M. Hassler, a program director at SwRI and principal investigator of the RAD investigation. “These measurements will be used to better understand how radiation travels through deep space and how it is affected and changed by the spacecraft structure itself. The spacecraft protects somewhat against lower energy particles, but others can propagate through the structure unchanged or break down into secondary particles.”
After Curiosity landed on Mars in August, the RAD instrument continued operating, measuring the radiation environment on the planet’s surface. RAD data collected during Curiosity’s science mission will continue to inform plans to protect astronauts as NASA designs future missions to Mars in the coming decades.
SwRI, together with Christian Albrechts University in Kiel, Germany, built RAD with funding from NASA’s Human Exploration and Operations Mission Directorate and Germany’s national aerospace research center, Deutsches Zentrum für Luft- und Raumfahrt.Read more