Articles tagged with Sun
The SECCHI team has obtained images of large waves of solar material sweeping past Earth, confirming the existence of previously known point measurements. The waves are associated with high-density regions that rotate with the Sun and are believed to form as high-speed wind from coronal holes runs into low-speed wind.
Hinode satellite data sheds light on sun's magnetic field and solar wind formation, revealing Alfvén waves play a critical role in driving the solar wind. Magnetic reconnection and convective motions also contribute to its creation.
A team of astronomers, led by Dr. Edo Berger, have observed a surprisingly active magnetic field on the ultracool low-mass star TVLM513-46546, challenging the theory that cooler stars are simple and quiet. The star's complex magnetic field environment may indicate unusual activity beneath its surface or possibly even an unseen companion.
Researchers at UCL have identified a critical point of no return for gas giants, beyond which their atmospheres become unstable and rapidly expand. At this threshold, the cooling mechanism breaks down, leading to catastrophic consequences.
Computer simulation predicts Voyager 2 will reach major milestone in space, crossing the 'termination shock' one more time in mid-2008. The spacecraft's expected crossing of the spherical shell marks a significant event in its journey into interstellar space.
Astronomers have discovered a massive black hole with a mass 24 to 33 times that of our Sun, exceeding expectations. The discovery was made using two NASA satellites and suggests that stellar-mass black holes can be much larger than previously thought.
The Sunrise project successfully launched a solar telescope to an altitude of 120,000 feet, enabling scientists to view features of the Sun that were previously unseen. The telescope will capture stable images in the ultraviolet range, allowing for higher resolution than can be obtained from Earth's surface.
Researchers found a planet orbiting a star near its end of life, providing insights into the potential fate of our own planet. The discovery suggests that planetary systems can survive the sun's expansion and helium flash, but larger planets may still be vulnerable.
The Extreme Ultraviolet Variability Experiment (EVE) will measure the sun's ultraviolet radiation changes, causing outages in radio communications and affecting satellites. EVE will provide space weather forecasters with warnings of potential communications and navigation outages every ten seconds.
Researchers have observed elusive oscillations in the Sun's corona, known as Alfvén waves, that transport energy outward from the surface of the Sun. These discoveries can help unlock secrets of the corona's heat and solar storms, and improve our understanding of how the Sun affects Earth.
The Virginia Tech research team has observed tell-tale signals of low-energy solar neutrinos for the first time, providing evidence for the validity of a model of solar energy generation. The detection was made possible by a new technology that eliminated background contaminants and achieved unprecedented purities in the detector.
Scientists say polar ice clouds could be a symptom of climate change due to increased carbon dioxide in the lower atmosphere causing cooling in the upper atmosphere. Noctilucent clouds form under conditions that counter common logic, only forming in summer when solar radiation is most intense.
Princeton physicists have made the first real-time observation of low-energy solar neutrinos, confirming a long-held theory about the sun's nuclear reactions. The observation provides precise measurements of the neutrinos' energy and confirms that we understand how the sun shines.
The discovery of a planet orbiting a giant red star provides insight into the potential fate of our solar system as it evolves into a red-giant star. The planet, located 300 light years from Earth, circles its star every 360 days and offers astronomers a unique opportunity to study the effects of red-giant stars on planetary systems.
Researchers suggest that perennial water-ice deposits at Mars' South Pole are juggled between the North and South Poles every 51,000 years due to precession. Water vapour is transported from the North Pole to the South Pole, where it re-condenses and freezes, forming a thick layer.
Researchers at UCL have detected water vapor in the atmosphere of an extrasolar planet, HD 189733b. The discovery was made using NASA's Spitzer telescope and confirms that water might be more common than previously thought outside our Solar System.
Researchers have identified a silent, natural disaster that silently wipes out coral reefs on clear sunny days during extreme low tides. The study reveals that these events are highly predictable and can be anticipated through alignment of weather patterns and tidal charts.
CMEs can produce radiation storms, but detecting them through radio signals may provide warning to astronauts and satellite operators. Strong CME shocks accelerate particles in the solar wind, producing both radio signals and radiation storms.
Astronomers have determined the properties of a rare binary star system using NASA's FUSE satellite and ground-based telescopes. The system, LH54-425, consists of two massive O-stars with combined mass of about 100 suns, orbiting each other every 2.25 days.
Researchers have successfully applied a new method to determine the masses of black holes in binary systems, including Cygnus X-1 and NGC 5408. The technique takes advantage of X-ray observations of quasi-periodic oscillations (QPOs) and their relationship with the accretion disk.
Scientists observed large fluctuations in magnetic and electric field readings around each spacecraft, revealing variations in solar wind protons reflected by the shock. This discovery provides valuable insights into bow shocks around distant celestial objects, which can accelerate particles to extreme energies.
The US Naval Academy is partnering with NASA to build a satellite called MidSTAR-2, which will carry four experiments into space in 2011. The satellite will study the Earth's thermosphere, gamma rays, and solar winds, providing valuable insights into these phenomena.
Researchers have found strong evidence that Mercury's core is molten, a discovery that could explain the planet's weak magnetic field. The study used a novel technique to detect tiny twists in Mercury's spin, which occurred as the sun's gravity exerted alternating torques on the planet.
A team of German astronomers has identified a new globular cluster in the Milky Way, comprising approximately 100,000 stars. The discovery is significant as it provides unique laboratory conditions to investigate various aspects of astrophysics and sheds light on the formation and evolution of galaxies.
Researchers at Yale University and the University of Leicester have discovered an ancient solar observatory at Chankillo, Peru, dating back to the 4th century B.C. The site features a line of 13 towers aligned with the sun's position throughout the year, making it the oldest complete solar observatory in the Americas.
Astronomers have identified an X-ray-emitting binary star system in the Small Magellanic Cloud, 170,000 light-years from Earth. The system, HD 5980, features two stars with intense winds that collide and produce multimillion-degree gas radiating brilliantly in X-rays.
The study measures infrared light from three gas giant planets, detecting no temperature differences between their day and night sides. Temperatures appear to be uniform, around 925 degrees Celsius, due to strong winds that mix the atmosphere planetwide.
Scientists have identified a new type of massive stellar death, where stars may collapse into black holes without exploding in supernova explosions. This discovery was made using data from two long-duration Gamma-ray bursts detected by NASA's Swift satellite.
Research reveals tidal motion affects West Antarctic Ice Sheet's largest ice stream, the Rutford Ice Stream, causing it to vary its speed by up to 20% every two weeks. This phenomenon, related to ocean tides and gravitational effects of the sun and moon, has important implications for predicting sea level rise.
The analysis of Stardust particles from comet Wild 2 has revealed clues about the birth of our solar system, challenging some basic theories. The particles contain osbornite, a mineral that forms at high temperatures, indicating a volatile and dynamic environment during the solar system's infancy.
A space sunshade, proposed by University of Arizona astronomer Roger Angel, could balance the heating effect of a doubling of atmospheric carbon dioxide. The constellation of small spacecraft would form a long, cylindrical cloud with about 10 percent of sunlight diverted away from Earth.
Mars Express's OMEGA instrument reveals a thick slab of dry ice in the cryptic region, but dust contamination is caused by geysers triggered by sunlight heating the soil beneath. The geysers create spots and fans, which suggest a process that could significantly contribute to the dust contamination observed.
Researchers found an isolated bacterial community thriving in rock fracture water two miles beneath the surface. The unique microbes depend solely on geologically produced sulfur and hydrogen for energy, challenging the notion of life's reliance on sunlight.
Researchers have directly imaged a faint brown dwarf companion to the star HD 3651, which hosts a planet. The discovery provides valuable information on planetary formation and offers a unique insight into the co-formation of planets and brown dwarfs around the same star.
Astronomers discover sun was born in a massive star cluster, challenging current theories on planetary formation. The researchers used radioactive isotopes from meteorites to calculate the distance and time of a nearby supernova, suggesting that hundreds or thousands of solar siblings may exist.
Astronomers used VISIR instrument to map infrared disc around young, massive star HD 97048, finding it at least 12 times larger than Neptune's orbit. The disc is flared and contains a large amount of gas, potentially hosting planetary embryos.
The Johns Hopkins University Applied Physics Laboratory-built STEREO spacecraft will explore coronal mass ejections and their impact on Earth. The twin observatories will capture 3D images and particle measurements of the sun by flying as mirror images of each other.
Astronomers use Hubble Space Telescope to image two mysterious star types, including tiny, slow-burning stars and ancient, giant white dwarfs. The research pushes limits of observatory's capabilities, gathering data that will help refine theories about low-mass stars and the universe's age.
Astronomers discovered a brown dwarf in close orbit around a white dwarf, with a separation of less than 2/3 of the Sun's radius. The system formed after the red giant engulfed its companion and ejected its envelope, leaving behind a binary system.
Scientists at NASA's Marshall Space Flight Center highlight the dangers of lightning during National Lightning Safety Awareness Week. The study reveals that over 8 million cloud-to-ground lighting strikes occur daily worldwide, with an average of 67 deaths annually in the US.
The University of New Hampshire has delivered two identical Plasma and SupraThermal Ion Composition (PLASTIC) instruments for NASA's STEREO mission, which aims to study coronal mass ejections and their impact on space weather. The instruments will make measurements of the solar wind as they pass by the twin spacecraft.
A study by the University of Alberta and international partners reveals that past changes in solar radiation have already affected tropical glaciers. Future climate change poses a significant threat to water resources in these regions, as high-altitude glaciers continue to melt rapidly.
Scientists will study the direction and velocity of flows in the corona, a phenomenon visible only during total eclipses. The event also marks NASA's annual Sun-Earth Day program, highlighting the interactions between the sun and our planet.
A new study by the University of Colorado at Boulder suggests that Saturn's ring spokes may become visible again by July due to changes in the planet's orbit and tilt. The spokes, which are up to 6,000 miles long, were first spotted 26 years ago but disappeared shortly after the Cassini spacecraft arrived in 2004.
The Planetary Society and ESA celebrate the imagined rugged beauty of Venus with the winning entries in the 'Postcards from Venus' art contest. The Grand Prize winner, Tatianna Cwick, age 17, has won a trip to the European Space Operations Centre. Other winners include Yoo-Hong Sun, age 9, and Alejandra Gonzalez Quintana, Spain.
Margaret Turnbull has shortlisted five stars for radio signal detection and five for direct imaging of Earth-like planets. Her criteria include age, metallicity, and residency on the main sequence, favoring Sun-like stars with stable orbits.
The Finnish SIXS instrument will measure the Sun's X-ray and particle radiation on Mercury, providing valuable data on the planet's surface and magnetosphere. The instrument is part of the BepiColombo mission, a European Space Agency project that aims to explore Mercury's orbit and composition.
Astronomers discovered dusty disks around two massive stars, suggesting that planets might form and survive in hostile environments. The discovery expands the range of known conditions for complex dust grain formation and potentially indicates that these stars are forming planets.
Astronomers have discovered a new planet, 2003 UB313, which is larger than Pluto and located in the Kuiper Belt. The object's size was determined through thermal emission measurements, revealing a diameter of approximately 3000 km.
Astronomers have discovered two bright debris disks around nearby stars, similar to our own solar system's Kuiper Belt. These narrow disks are believed to be shaped by the presence of a star-like companion that continually grooms their edges.
Scientists confirm that dark matter dominates the total mass of our home galaxy, the Milky Way, through the Radial Velocity Experiment (RAVE) survey. The team aims to measure the speed, temperature, surface gravity and composition of up to a million stars passing near the sun.
Astronomers have mapped the outflow from two regions of star formation in the Orion Nebula, providing new insights into the process of star creation. The study used Hubble Space Telescope data to track shock waves and determine the duration of stellar winds, shedding light on how these winds shape the surrounding clouds.
Researchers discovered young super nebulae around giant star clusters, containing up to a million young stars, and emitting radiant power billions of times that of the sun. The discovery raises questions about why Milky Way no longer forms similar clusters after 10 billion years.
UI researchers discovered a giant star orbiting a 'medium-sized' black hole every 62 days, indicating the star's enormous size and brightness in X-rays. This finding may help confirm a class of black holes with masses between 100 and 10,000 solar masses.
Researchers isolated Sirius B's light using Hubble Space Telescope, measuring its mass based on gravitational redshift. The result indicates Sirius B has a diameter less than Earth's but is denser and has a surface temperature of 25,000 degrees C.
Researchers create an optical vortex mask that eliminates starlight, allowing for direct observation of nearby planets. The device successfully images Saturn and its rings, paving the way for future exoplanet detection projects like the Terrestrial Planet Finder.
The two Solar TErrestrial RElations Observatory (STEREO) spacecraft will explore coronal mass ejections' origin, evolution, and interplanetary consequences during their two-year mission. The STEREO mission aims to improve our understanding of space weather and its impact on Earth systems.
Researchers have identified two distinct formation times for chondrules in the Gujba and Hammadah al Hamra meteorites, contradicting the linear process of solar system evolution. The discovery suggests that giant plumes of vapor produced by planetary collisions may have formed these chondrules much later than previously thought.
The discovery provides the first conclusive evidence that a 'protosun' played a major role in chemically shaping the solar system by emitting ultraviolet energy. The team used a technique to reveal details about the Earth's early atmosphere from variations in oxygen and sulfur isotopes, indicating the presence of photochemical reactions.
A study by Yale University and NOAA finds that direct sunlight affects weather balloon temperature probes, leading to discrepancies in global warming estimates. This correction reveals an increase of 0.2 degrees Celsius per decade in average global temperature over the last thirty years.