footage of the solar corona during three explosions
Images taken on 21 October 2010 by the SDO (Solar Dynamics Observatory) space telescope launched on 11 February 2010 by NASA to study the Sun. False colors represent images taken with different filters, sensitive to different temperatures of the solar crown: blue indicates 1,000 ° C; green 1,500 ° C; the red 2,000 ° C. The video shows three simultaneous explosions: one near the center of the disk and two on opposite sides of the Sun. Together they cover over 1,600,000 km.
The video was processed using material from NASA, the American space agency.
The origin of life on Earth? Here is the answer from NASA / Video
About 4 billion years ago, the sun was only three-quarters of the brightness it has today, but its surface was bubbling with gigantic eruptions, which 'spewed' huge amounts of material and radiation into space. Well, these powerful solar explosions not only could have provided the energy needed to heat the Earth, but the eruptions could have provided the energy to transform simple molecules into complex molecules, such as RNA and DNA, needed for development. of life on Earth.
This is supported by research published in 'Nature Geoscience' last May 23 by a team of NASA scientists. "At that time, the Earth received only 70 percent of the energy from the sun compared to today," said Vladimir Airapetian, lead author of the study and solar scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. that the Earth should have been a ball of ice. "
"Instead it is the other way around - continues Airapetian - there is geological evidence showing that the Earth was a hot globe with liquid water. Our research shows that solar storms could have been central to the warming of the Earth". The atmosphere of the early Earth was also different from what it is now: molecular nitrogen - that is, two nitrogen atoms bound together in a molecule - made up 90 percent of the atmosphere, up from 78 percent today.
This constant influx of solar particles to Earth may also have provided the energy needed to make complex chemicals. Solar particles and solar radiation would have helped to increase the amount of nitrogen, freeing the atoms after entering the atmosphere and giving life to complex molecules necessary for the birth of life.
4 Blasts in Kabul City, Sources Say Medical Workers Injured
The first blast occurred at 8:04 am local time in the Despechari area in PD15 of Kabul city.
Four explosions at separate locations occurred in Kabul on Wednesday, with Kabul police so far confirming that two police personnel were wounded in the Despechari area and a source claiming that two police had been killed and two more were wounded in the Salim Karwan area.
The first explosion in the Despechari area of PD15 in Kabul occurred around 8:04 am and was caused by a magnetic mine, said police, wounding two police personnel.
The second blast happened in the Salim Karwan area in PD12 of Kabul city and targeted a police vehicle, killing two police and wounded two others, a security source said. The police have not confirmed this.
The third blast was reported in the Shahr-e-Naw area of Kabul in the afternoon, and police said there were no casualties.
The fourth explosion struck a vehicle in the Golayee Dawakhana area in the western part of Kabul city, leaving at least two people wounded, sources confirmed.
Meanwhile, At least two Afghan policemen were killed in an attack on their post in Tawalat village of Paghman district in Kabul on Wednesday afternoon, a security source told TOLOnews. The attackers also seized police weapons, the source said.
According to the security sources, the targeted vehicle belongs to a mental health hospital and three of its doctors have been wounded in the blast.
No group including the Taliban has claimed responsibility for the blasts.
On Tuesday a blast from a magnetic mine killed one person and wounded another in a civilian vehicle, Kabul police said.
Four Blasts Happen in Kabul Two Killed
Two security force members were killed and six more were wounded in the blasts, security sources and police said.
Kabul started the first day of the week with four explosions that happened in less than three hours in various parts of the city, adding to the panic among the people who have been witnessing similar incidents nearly every day over the last few weeks.
Police and security sources said that at least two security force members were killed and six more were wounded in the blasts.
The first explosion happened at around 7:02 a.m. on Saturday morning in the Chaman-e-Hozoori area in Kabul's PD8, leaving no casualties, according to police. The incident was a magnetic IED blast, police said.
The second explosion happened in the west of Kabul at around 7:05 a.m. in which a magnetic IED blast targeted a vehicle carrying a senior official from the VIP protection unit, police said.
According to police, two police force members were wounded in the blast.
The third explosion happened in Deh Sabz area in the east of Kabul. Police said it was a roadside bomb blast that targeted a police vehicle in which three security force members were wounded.
The fourth blast happened in Deh Bori area in the west of Kabul at around 9:05 a.m. in which a police vehicle was targeted, police said.
Police added that two police force members were killed and a civilian was wounded in the blast.
Photos on social media show that some houses and shops have been damaged in the explosion in Deh Bori area.
The increase in blasts and violence in various parts of the country come amidst peace efforts.
The enigma of solar explosions - Scientists Shed Light On Riddle of Sun's Explosive Events
What causes the coronal mass explosions that occur on our star, and which are a danger to artificial satellites and communications networks on Earth? From the USA, a computer simulation tries to answer.
Solar physicists have been fighting for decades: what causes the "coronal mass ejections", the violent explosions that project plasma outside the solar corona and can cause heavy effects on terrestrial systems such as artificial satellites, among other things or electrical and communications networks? A study in Nature Physics tries to answer, using a computer model to explain how the magnetic processes that occur inside the Sun can give rise to the violent phenomena that occur in the corona. "Thanks to this type of computer simulation we are able to understand how invisible interweaving of magnetic fields emerge from beneath the surface of the Sun and propagate through interplanetary space, reaching the Earth" explains Noé Lugaz of the Institute for the Study of Earth, Oceans, and Space of the University of New Hampshire, one of the authors of the study.
Scientists Shed Light On Riddle of Sun's Explosive Events
Four decades of active research and debate by the solar physics community have failed to bring consensus on what drives the sun's powerful coronal mass ejections (CMEs) that can have profound "space weather" effects on Earth-based power grids and satellites in near-Earth geospace. In a paper just published in Nature Physics, an international team of space scientists, including a researcher from the University of New Hampshire's Space Science Center (SSC), explains the mysterious physical mechanisms underlying the origin of CMEs. Their findings, based on state-of-the-art computer simulations, show the intricate connection between motions in the sun's interior and these eruptions and could lead to better forecasting of hazardous space weather conditions.
Where and How?
While searching for an explanation of particle acceleration on the Sun, British researchers in the 1950s, in particular Peter Sweet and James Dungey, proposed the idea of magnetic reconnection, an idea later applied to the Earth's magnetosphere and to substorms. Reconnection is still believed to be the energy source of flares and CMEs, but unfortunately, it seems to happen in the lower corona, where magnetic structures are invisible (with a few exceptions - see picture below). The nature of substorms and solar acceleration events may indeed be similar, though their scales differ greatly. However, satellites can be sent to substorms but not to the Sun, and therefore magnetospheric research may well hold clues to some of the problems of solar physics.
|Theorists have proposed that reconnection and acceleration on the Sun occur near the tops of magnetic "arches," of field lines rising from sunspot regions, like the one pictured above. When the Solar Maximum Mission in 1981 spotted on the Sun's surface two bright pin-point sources of x-rays, appearing at the beginning of an acceleration event, it was widely assumed that they marked the impact of beams of electrons accelerated at the top of an "arch" and guided by its field lines down to the Sun. More recently, the Japanese x-ray imager aboard the Yohkoh satellite has observed a bright x-ray source formed at the top of an arch (picture on right), lending further support to the theory.|
|Flare seen in X-rays by Yohkoh.|
About 5 billion years ago, a vast, cold cloud of interstellar gas and dust, called a nebula, began to collapse. A star formed at the center, surrounded by a spinning disk of gas and dust. Small grains condensed, accreted into smaller rocky bodies, and ultimately grew into planets. Thus was born our solar system — the Sun and all the planets, moons, comets, asteroids, and meteoroids that revolve around it.
This solar nebula theory is well supported by modern astronomical observations of other nebulas, disks, and planets, and by radiometric dating. Samples of the Moon, Earth, Mars, and meteorites (the remnants of meteoroids that entered the atmosphere as meteors and landed on Earth) have a similar age of 4.56 billion years. The evidence implies that planets are a natural byproduct of star formation and that solar systems are common throughout the universe.
However, what initially caused the nebula to begin to collapse remains unknown. Some researchers suggest the death of a distant massive star in a violent, luminous explosion called a supernova sent a shock wave through space, compressing the cloud. Others argue that a supernova shock wave would scatter a gas and dust cloud, rather than collapse it. They propose instead that radiation emitted by a nearby massive star prior to its death could have nudged the nebula to collapse.
The debate centers on evidence from meteorites, which preserve a record of the chemical composition and conditions at the time of solar system formation. Researchers have found nickel-60 in the grains of meteorites. Nickel-60 is a radioactive decay product of iron-60, which forms inside massive stars and is dispersed by supernovas. Iron-60 decays rapidly into nickel-60, allowing scientists to use it like a clock. The presence of nickel-60 means that a supernova happened around the time that solid grains (later found in meteorites) began to condense out of the cloud.
This is tantalizing evidence that a supernova may have triggered the birth of the solar system — with the shock wave injecting iron and triggering the collapse at the same time. In contrast, proponents of the hypothesis that radiation from a nearby star collapsed the cloud believe the iron was injected later — by the supernova of that star — after the Sun and planets had already begun to form.
More research is needed to determine whether the birth of the solar system was triggered by a distant supernova or radiation from a nearby star, or possibly something else. An emerging hypothesis holds that no one star contributed the iron-60 and other short-lived radionuclides, but that they instead came from an ensemble of massive stars that formed in the nebula before the solar system.
In addition to iron-60, scientists are studying other short-lived radionuclides found in meteorites, such as aluminum-26, manganese-53, and iodine-129, which form in different ways, in stars of different masses, and have different half -lives. Thus, the proportion in which they appear can isolate which events occurred — in the right place, at the right time — to trigger the birth of the solar system and, ultimately, all life on Earth.
Video: Discovery Channel - Large Asteroid Impact Simulation