| Solar News --2009--
November 24, 2009  "Magnetic Tsunamis" on the Sun are Real In February 2009, sunspot 11012 unexpectedly erupted, hurling a coronal mass ejection (a "CME") into space and sending a magnetic "tsunami" racing along the Sun's surface, confirming the existence of a phenomenon first observed in 1997. The propagation of these giant waves can help scientists gather information about the Sun's lower atmosphere and pinpoint the origin of CME's. Image Credit: NASA. News source: science.nasa.gov November 14, 2009 Lightning Strikes Help Determine Sun's Rotation A team of researchers recently found a correlation between the VLF (very low frequency) radio signal from lightning strikes and the Sun's 27-day rotation cycle. Although the phenomenon is not yet well understood, solar rotation appears to affect ionization in the Earth's ionosphere, which in turn causes variation in the strength of the signal. News source: sciencedaily.com October 27, 2009  The Sun's Sneaky Variability Is the Sun getting brighter or dimmer? While the Sun appears to remain at a constant level based on what we see in visible light, the Sun's extreme ultraviolet (EUV) output can vary significantly. To monitor EUV activity in high resolution, NASA is going to launch a sensor named "EVE," short for EUV Variability Experiment, onboard the Solar Dynamics Observatory as early as this winter. Image Credit: NASA. News source: science.nasa.gov September 29, 2009 Cosmic Ray Activity at Space Age High In 2009, the intensities of galactic cosmic rays have increased 19% over the highest seen in the last 50 years. The main cause is the deep solar minimum which was first observed around 2007 and continues today. When solar activity decreases, the Sun's magnetic field is weakend, and provides less protection against the charged, high-energy cosmic particles (mainly protons), so more of them are able to reach the inner solar system. Cosmic rays can pose a radiation hazard for astronauts and satellites. News source: science.nasa.gov September 3, 2009 Are Sunspots Disappearing? The present solar minimum, the deepest in nearly a century, has researchers wondering when sunspots will return in significant numbers. News source: science.nasa.gov July 20, 2009 Solar Eclipse Wednesday, July 22 The longest solar eclipse of the 21st century took place Wednesday, July 22nd. The path of totality crossed many major cities in Asia. Visit our Eclipse Page News source: science.nasa.gov June 17, 2009 Mystery of the Missing Sunspots Solved? Solar physicists have made a discovery that helps explain the puzzling lack of sunspots over the last two years. Using the technique of helioseismology, researchers discovered that a jet stream deep below the surface of the Sun is migrating slower than usual through the Sun's interior, giving rise to the current lack of sunspots. The Sun generates new jet streams of plasma near its poles every 11 years. These streams migrate from the poles to the equator and when a jet stream reaches the critical latitude of 22 degrees, new cycle sunspots begin to appear. News source: science.nasa.gov June 3, 2009 Fake Astronaut Gets Hit by Artificial Solar Storm NASA is planning to send missions to the Moon to set up a manned outpost, and eventually to send humans to Mars. This means astronauts may spend months or even years outside the Earth's magnetic field, so NASA is studying the biological effects of radiation associated with extreme space weather. Scientists are using a high-energy proton beam at NASA's Space Radiation Lab in Brookhaven to simulate a solar storm right here on Earth. And they're testing its effects on a life-size plastic replica of a human torso containing real human DNA. News source: science.nasa.gov May 29, 2009 New Solar Cycle Prediction In recent months the Sun has shown signs of life, with increasing numbers of sunspots and slightly increased radio emissions - precursors of the new Solar Cycle 24. Using new models, experts led by NOAA predict that Solar Cycle 24 will peak in May 2013 with a below-average number of sunspots compared to previous years. But the Sun should remain relatively calm for at least another year. News source: science.nasa.gov April 19, 2009 New Model of Solar 'Sigmoid' Structures Recently, the Hinode spacecraft has obtained the first high-resolution images of a solar sigmoid. 'Sigmoids' are S-shaped structures which occur in the solar corona, and form during the initial stages leading to solar flare eruptions. Now researchers have developed a new model to explain the nature of sigmoids during different stages of their life, helping them to better understand how solar flares occur. News source: www.sciencedaily.com April 14, 2009  The Surprising Shape of Solar Storms When forecasting severe space weather, it is important to be able to predict the speed and trajectory of Coronal Mass Ejections (CMEs) - high-speed storms of hot plasma originating in the solar corona. Altough thousands of CMEs have been observed in the past, their common shape was unknown until now. Researchers studying data from NASA's two STEREO spacecraft have found that CMEs are shaped like a French pastry, or a rope twisted in knots. Knowing the shape of CMEs allows scientists to accurately estimate their speed and trajectory, and this new "croissant" model is expected to dramatically improve forecasts of severe space weather. Image Credit: NASA. News source: science.nasa.gov April 1, 2009  Deep Solar Minimum is Observed The sunspot count has dropped from last year, with no sunspots observed on 78 out of 90 days so far in 2009. Additionally, according to NASA, we are experiencing a 50-year low point in solar wind pressure, a 55-year low in solar radio emissions, and a 12-year low in solar irradiance! These lows have sparked a debate about whether the current minimum is "weird" or just a "correction" following a period of intense solar activity. See also: Quiet Sun baffling astronomers Image Credit: NASA. News source: science.nasa.gov, news.bbc.co.uk March 29, 2009 New Satellite To Track Total Solar Irradiance NASA plans to launch the Glory satellite in fall of 2009, a spacecraft that will accurately measure fluctuations in Total Solar Irradiance (TSI) from above the atmosphere. Glory will be equipped with the Total Irradiance Monitor (TIM) instrument that will measure how much heat in the Earth's atmosphere is produced by solar radiation. Scientists will use the data to determine what influence the Sun’s TSI output has on the pace of climate change. News source: www.sciencedaily.com
March 20, 2009 New Waves Discovered in Lower Solar Atmosphere Scientists have discovered evidence of new giant waves in the lower atmosphere of the Sun. They detected vertically propagating oscillations which are a signature of a new type of solar wave, called the Alfven wave. This discovery helps to explain why the region outside the Sun (the corona), is much hotter than the surface of the Sun (the photosphere), which was not well understood for many decades. In the past, the Alfven wave was proposed as one possible mechanism that carries energy into the corona, and scientists now believe this flux is sufficient to cause heating of the corona. News source: www.sciencedaily.com
February 25, 2009 Otherworldly Solar Eclipse Photographed For the first time, a spacecraft from Earth has captured hi-resolution images of a solar eclipse while orbiting another world. Japan's Kaguya lunar orbiter accomplished the feat on Feb. 9, 2009, when the Sun, Earth and Moon lined up in a nearly perfect row. News source: science.nasa.gov
January 26, 2009  NASA Plans to View the "Dark Side" of the Sun The Sun rotates at a rate of one revolution every 27 days, but we can only observe half of its surface at any given time. In February of 2011, astronomers will for the first time be able to view the whole surface of the Sun, thanks to NASA's two STEREO spacecraft, which will be deployed 180 degrees apart. Image Credit: NASA. News source: science.nasa.gov |