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(Image: © NASA/Johns Hopkins APL/Steve Gribben) NASA's daring Parker Solar Probe made its fifth daring flyby of the sun this weekend. The spacecraft has been conducting a marathon of solar observations since May 9 as scientists affiliated with the mission look to crack more secrets about how the sun works. The observations will continue until June 28, totaling more than seven weeks of measurements during the probe's fifth swing past the sun. The closest approach of this orbit, called a perihelion, occurred at 4:23 a.m. EDT (0823 GMT) on Sunday, June 7. At that time, the probe was about 11.6 million miles (18.7 million kilometers) from the sun's surface and was travelling at over 244,000 mph (393,000 km/ph) relative to the sun. Parker Solar Probe launched in August 2018 on a mission to study the sun's outer atmosphere, called the corona. Parker Solar Probe is outfitted with four different instrument suites to try to solve two key mysteries that the corona poses for scientists who want to understand the workings of our star and others like it. First, the corona incredibly hot, millions of degrees no matter which scale you use and far hotter than the visible surface of the sun. Scientists want to understand how this region achieves such eye-watering temperatures. Second, the corona serves as a launch pad for the solar wind, the stream of charged particles that flows off the sun and across the solar system. The solar wind reaches incredible speeds in the corona, and scientists also want to understand how that process occurs. This weekend's fifth perihelion is also the prelude to another intriguing event. On July 10 (July 11 GMT), the Parker Solar Probe will conduct a flyby of Venus. The maneuver is one in a series that is vital to speed the spacecraft up enough to continue creeping toward the sun, giving the probe ever-closer views of the star during perihelion passes. But the July flyby will also be a prime opportunity to study Earth's neighbor, as the spacecraft will pass just 517 miles (832 km) above the surface of Venus. In particular, this flyby should give scientists vital information about how the atmosphere of Venus dribbles away from the planet in what scientists call its tail. It's the sort of bonus science that missions love. And the flyby will nudge Parker Solar Probe closer to its main target during subsequent perihelion maneuvers. By the end of the mission, in late 2025, the spacecraft will be soaring just 4 million miles (6 million km) away from the sun's surface. Here 5 new discoveries about the sun brought by the probe:
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You can say what you like about our nearest star, but as this latest solar eruption proves, it certainly has impeccable timing. On Monday (Dec. 28), a sunspot cluster erupted, blasting an M-class flare directly at Earth. The extreme-ultraviolet radiation immediately washed over our upper atmosphere, initiating an ionization event that caused a radio blackout over South America, Africa and the south Atlantic Ocean. The blackout may have been detected by mariners and ham radio operators in the 20MHz frequency range, according to SpaceWeather.com Although the flare certainly wasn’t of the strength of a major X-class flare (the most powerful class of flare), this event did trigger a significant coronal mass ejection (CME) that is currently racing in the direction of Earth. Space weather forecasters predict a direct hit with Earth’s magnetic field on or around New Year’s Eve, potentially sparking some natural fireworks in the upper atmosphere just in time for 2016. “Sunspot AR2374 has an unstable ‘beta-gamma’ magnetic field that could explode again in the hours ahead,” writes NASA’s Tony Phillips for SpaceWeather.com. “NOAA forecasters estimate a 55 percent chance of additional M-class flares and a 10 percent chance of X-flares on Dec. 28th.” Flares and CMEs are different beasts triggered by the same magnetic phenomenon. During periods of high magnetic activity on the sun, the sun’s internal magnetic field forces its way through the sun’s photosphere (colloquially known as the sun’s “surface”). This magnetism exposes the inner sun, which is counter-intuitively cooler (and therefore appears darker) than the sun’s chromosphere (the layer of atmosphere above the photosphere) and corona (the sun’s extended and multi-million degree atmosphere). Therefore, magnetically active regions can be easily seen on the sun’s disk as spots and clusters of dark spots known as “sunspots.” As the magnetic field lines become forced together above these sunspots, magnetic reconnection may occur, accelerating solar plasma to relativistic speeds, generating intense bursts of radiation. These are solar flares and their radiation reaches Earth in minutes. However, CME’s are bubbles of magnetized high-energy plasma that are ejected into space at high speed, but nowhere near relativistic speeds. CMEs can reach Earth in several hours or a few days, depending on the ferocity of the eruption. And today’s flare and CME happened to be generated by the same sunspot that was Earth-directed, maximizing our chances of having a geomagnetic storm right in time for New Year’s. So if you live in high latitudes, and pay attention to the sky, you may be in for a New Year treat as high-energy solar particles impact our atmospheric gases, generating bright aurora. Source http://www.space.com/31484-sun-blasts-flare-at-earth-new-year-s-eve-storm.html
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When the sun huffs and puffs, its solar wind blows part of Mars' atmosphere out to space. That's the key finding announced at a NASA press conference on Thursday by researchers working on the Mars Atmosphere and Volatile Evolution (MAVEN) mission. The MAVEN mission's spacecraft has been circling the Red Planet for over a year now to study its atmosphere and determine how so much of it was lost over its history, transforming it from a once wet and warm Earth-like planet to the cold, dry place of so many sci-fi storylines. Figuring out what happened to the Martian atmosphere is a big deal because it helps scientists understand why some planets can or can't host life while others like Mars go from potential beach destination to inhospitable. The culprit in the loss of Mars' atmosphere is the solar wind, a stream of mostly protons and electrons flowing from our star's atmosphere at a speed of about a million miles per hour. The solar wind also carries a magnetic field that can generate an electric field as it flows past Mars. This electric field is then capable of accelerating electrically charged gas ions in the planet's upper atmosphere and shooting them out into space, similar to the way a baseball might be launched out of the field of play when a batter hits a high foul ball or home run. MAVEN has eight sensors that gather data on Mars' upper atmosphere and its interaction with the sun and solar wind. According to MAVEN measurements, the solar wind strips away gas in the Martian atmosphere at a rate of about 100 grams (roughly a quarter pound) every second. "Like the theft of a few coins from a cash register every day, the loss becomes significant over time," said Bruce Jakosky, MAVEN principal investigator at the University of Colorado-Boulder. "We've seen that the atmospheric erosion increases significantly during solar storms, so we think the loss rate was much higher billions of years ago when the sun was young and more active." Jakosky added that geology on Mars seems to show that water was abundant on the planet until about 3.7 billion years ago, leading the researchers to hypothesize that more active solar storms stripped away most of the atmosphere during a period sometime between 3.7 billion and 4.2 billion years ago. The fact that the sun is less active and prone to big solar wind storms today is just one reason Jakosky says we shouldn't worry too much about something similar happening to Earth's atmosphere anytime soon. The other factor that protects our planet from turning into a dead, frozen hellscape is Earth's rocking magnetic field that shields us from the brunt of the solar wind's wrath. Mars has no such magnetic field to protect its upper atmosphere from the ion-stripping effects of the solar wind. "Understanding what happened to the Mars atmosphere will inform our knowledge of the dynamics and evolution of any planetary atmosphere," NASA's John Grunsfeld said in a news release. "Learning what can cause changes to a planet's environment from one that could host microbes at the surface to one that doesn't is important to know, and is a key question that is being addressed in NASA's journey to Mars." Speaking of that trip to Mars, though, Jakosky added that dreams of someday releasing carbon dioxide sequestered in Mars to aid global warming and make the planet more like Earth will prove more difficult in light of the new findings. That's because Mars' carbon dioxide is "gone, it's blown away," he said. Maybe that's a good thing. Someone call Elon Musk and tell him to put away those nukes he wanted to use to kickstart the process. Source http://www.cnet.com/news/mars-atmosphere-was-likely-blown-away-by-the-sun/
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The sun blasted out a coronal mass ejection (CME), along with part of a solar filament, over a 3-hour period on Feb. 24, 2015. Credit: Solar Dynamics Observatory, NASA The U.S. government is getting more serious about dealing with the dangers posed by powerful sun storms. On Thursday (Oct. 29), the White House released two documents that together lay out the nation's official plan for mitigating the negative impacts of solar flares and other types of "space weather," which have the potential to wreak havoc on power grids and other key infrastructure here on Earth. The new "National Space Weather Strategy" outlines the basic framework the federal government will pursue to better understand, predict and recover from space-weather events, while the "National Space Weather Action Plan" details specific activities intended to help achieve this broad goal. [The Sun's Wrath: Worst Solar Storms in History] "The efforts undertaken to achieve the objectives of this strategy will establish a national approach to the security and resilience in the face of our improved understanding of the seriousness of the space-weather risk, and the steps we must take to prepare for it," Suzanne Spaulding, undersecretary for the U.S. Department of Homeland Security's National Protection and Programs Directorate, said Thursday during an event hosted by the White House Office of Science and Technology Policy (OSTP) that discussed the new documents. That risk is indeed serious, many experts say. High-energy solar flares aimed at Earth can affect the operation of orbiting satellites, and the most powerful emissions can even pose a risk to astronauts aboard the International Space Station. Of even larger concern are coronal mass ejections (CMEs), huge eruptions that send clouds of solar plasma streaking through space at millions of miles per hour. CMEs that hit Earth can spawn intense geomagnetic storms, with the potential to disrupt power grids, satellite navigation and radio communications temporarily. In March 1989, for example, a strong CME caused a blackout that left 6 million people in the Canadian province of Quebec without power for 9 hours, OSTP Director John Holdren said during Thursday's event, which was webcast live. An even more powerful CME slammed into Earth in 1859, generating beautiful auroral displays as far south as the Caribbean and causing the failure of telegraph systems in both Europe and North America. If a geomagnetic storm as strong as that one — which is known as the Carrington Event — were to strike today in our much more technologically advanced society, it would likely cause $600 billion to $2.6 trillion worth of damage in the United States alone, according to a recent study. "I'm not here saying the sky is falling, but it really is, if you think of millions of metric tons of charged particles coming to the Earth," said Terry Boston, president and CEO of the electricity transmission organization PJM. "Geomagnetic disturbances from space are a clear and present threat to the [electricity] system." The National Space Weather Strategy seeks to reduce that threat by focusing on six main goals: 1) Establish benchmarks showing how commonly severe space-weather events occur; 2) Improve the ability to respond to, and recover from, such events; 3) Reduce or eliminate vulnerabilities to flares and geomagnetic storms; 4) Improve predictions about impacts on critical infrastructure; 5) Improve forecasts of space-weather events, and knowledge of space weather more generally; and 6) Increase international cooperation (because impacts of extreme events will likely be felt across the globe). The Action Plan centers on the same six areas, going into detail about implementation. For example, the plan stipulates that NASA, the Department of Commerce, the Department of Defense and the National Science Foundation work together to complete, within the next year, an assessment of sensor technologies needed for better forecasting. That's just one of several requirements to make goal No. 5 a reality, according to the Action Plan. The collaborative, multidisciplinary approach laid out by the Strategy and the Action Plan puts the U.S. on the right path, said space-weather expert Louis Lanzerotti, of the New Jersey Institute of Technology. "I'm very impressed with this, and I think we have a strong start continuing forward in our country from the government, from academia and [the] private sector," Lanzerotti said at the OSTP event. Source http://www.space.com/30986-united-states-space-weather-plan.html
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Hey guys! Though I'd share some photos I uploaded today, that I took with my new camera. As it's spring, and this is when I do most of my photography, I'm going to be deleting some of my old uploads and replacing them with new ones as I keep taking more. Enjoy!- 8 replies
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