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Joke, I mean its not possible at all.. 🤭 or is it..? 🤔 By Micheal(channel: Vsauce).
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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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Giant comets that originate in the planetary fringes of the solar system pose a greater threat of colliding with Earth than do asteroids, which originate closer to the sun, a new review paper argues. In the last two decades, scientists have discovered hundreds of giant comets (known as centaurs) in the region near Jupiter, Saturn, Uranus and Neptune, according to a statement from the Royal Astronomical Society. No centaur poses a known immediate threat to Earth, but the discovery of this massive population has led a group of astronomers to re-assess the threat of these seemingly distant bodies to this planet. Estimates currently suggest that one of these giant comets crosses Earth's orbit on average only once every 40,000 to 100,000 years, at which time the comet is believed to break up into dust and debris that can collide with the planet. These collisions may be responsible for environmental upheavals in Earth's past; they may even be associated with the extinction of the dinosaurs 65 million years ago, the statement said. Centaurs are between 31 and 62 miles (50 and 100 kilometers) across and move in unstable orbits near the giant planets. Occasionally, the gravitational influence from one of these planets can send the centaur careening toward Earth. "In the last three decades, we have invested a lot of effort in tracking and analyzing the risk of a collision between the Earth and an asteroid," said Bill Napier, an honorary professor in the Centre for Astrobiology at the University of Buckingham in the United Kingdom, in the statement. Napier is first author on a review paper that aims to re-assess the threat of centaurs to the Earth. "Our work suggests we need to look beyond our immediate neighborhood, too, and look out beyond the orbit of Jupiter, to find centaurs," Napier said. "If we are right, then these distant comets could be a serious hazard, and it's time to understand them better." The statement said that "known severe upsets" of Earth's environment, accompanied by a disruption in how ancient civilizations evolved, mean that a centaur must have been in Earth's neighborhood roughly 30,000 years ago. This centaur would have shed clumps of debris ranging from fine dust to pieces several miles in diameter, some of which hit Earth. The researchers point to the existence of many submillimeter craters in rocks brought back from the moon by Apollo astronauts. (Because the moon has no geologic activity or atmosphere, craters are better preserved on its surface). Since the craters were mostly 30,000 years old or younger, it suggests an influx of dust in the solar system after that time period. Other environmental disruptions, in 10,000 B.C. and 2,300 B.C., suggest centaurs could have been responsible for changes in the Earth at those times, the statement said. The review paper was published in the Astronomy & Geophysics journal of the Royal Astronomical Society. Source http://www.space.com/31466-giant-comets-smash-earth.html
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Astronomers working with the Atacama Large Millimeter/submillimeter Array (ALMA) have discovered what they claim could be another large planet on the fringes of our solar system. While examining the Alpha Centauri star system, the nearest to Earth, they noticed a fast-moving object crossing their field of view. Its speed and brightness allowed them to rule out another star as the culprit, and based on wavelength readings obtained from ALMA, they believe it could be a Trans-Neptunian Object (TNO) orbiting the sun somewhere between 10 billion and 2 trillion miles from our home star. For comparison, Pluto is less than 4 billion miles away from the sun. Although the finding is intriguing, the news has been met with a healthy dose of skepticism. A New Member of the Solar System? Stars typically emit too much light for astronomers to discern any objects in their immediate vicinity, but the ALMA observatory was built to capture low-frequency wavelengths, allowing researchers to see objects that are closer to stars. This is how researchers noticed a mysterious object moving relative to Alpha Centauri, exhibiting what scientists call “proper motion.” The researchers suggest the object could be one of several celestial bodies, including a brown dwarf, a super-Earth (a planet larger than Earth but smaller than Neptune), or a much smaller, icy body orbiting beyond Pluto. Researchers posted their findings online Thursday to arXiv, but they are still awaiting peer review. Hold Your Horses While the possibility of adding another large planet to our solar neighborhood is exciting, the likelihood that this object, if it exists, is a so-called “super- Earth,” is probably quite small. The ALMA observatory can only look at a tiny fraction of the sky at any given moment. For their study, the researchers could only observe, at maximum, one arcminute, or 1/21,600th, of the heavens. To put that in perspective, the moon is 30 arcminutes across when full and viewed from Earth. Therefore, the odds that researchers happened to catch a large planet in their narrow gaze are pretty small. As Caltech astronomer Mike Brown pointed out via Twitter, "Fun fact: if it is true that ALMA accidentally discovered a massive outer solar system object in its tiny tiny tiny field of view, ... that would suggest that there are something like 200,000 earth sized planets in the outer solar system. Which, um, no." The far more likely possibility is that the astronomers captured one of the many icy objects floating beyond Pluto in the Kuiper Belt and the far-flung Oort Cloud. There are millions of such objects, ranging in size from less than a mile in diameter to almost 1,500 miles. And, as Bad Astronomy’s Phil Plait pointed out, the WISE observatory performed a comprehensive scan of the sky last year, and found no large planets beyond Pluto. WISE senses infrared radiation, which makes warm objects appear bright, so the absence of any WISE data means that the most probable identity of this newfound object in our solar system is a small, cold body orbiting far beyond Pluto. While this doesn’t entirely discount the presence of a super-Earth, it makes the probability very small —too small, perhaps, for us to warrant getting our hopes up too high. For now, we’ll just have to hold our breath and wait for these results to get vetted. Source http://www.astronomy.com/news/2015/12/a-new-planet-in-the-outer-solar-system-not-so-fast
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Large Asteroid Passes Close to Earth An asteroid the size of an aircraft carrier has flown by Earth in the closest encounter by a massive space rock in more than 30 years. The asteroid, named 2005 YU55, came within about 325,000 kilometers of the planet Tuesday evening (at 2328 UTC). The U.S. space agency, NASA, said there was no chance that the spherical rock would collide with Earth or the moon. The asteroid was traveling at more than 46,670 kilometers per hour. It passed closer to Earth than the moon. The last time an object the size of the asteroid traveled so near to Earth was in 1976. Scientists say it will be 2028 before another space object this large will fly by the planet. A scientist at the University of Arizona discovered the YU55 asteroid in 2005. NASA scientists planned to bounce radio waves off the asteroid and analyze the radar echoes. Those images should reveal details about the rock's surface features. YU55 is about 400 meters in diameter. Scientists believe it has been passing by Earth for thousands of years. It is one of about 8,500 near-Earth objects that NASA has catalogued. Source DJ
