The source of a huge flare that swept through our solar system has been pinpointed by scientists.
The discovery could help the understanding of gamma-ray bursts, the most powerful explosions in the universe.
Earth is hit by mild and short gamma-ray bursts regularly, on most days. But more rarely there are vast explosions, like the newly examined GRB 200415A, which bring with them a lashing of energy more powerful than our own Sun.
The flare seems to have emerged from an unusual, powerful neutron star known as a magnetar, scientists report in new findings published in Nature Astronomy.
“Our sun is a very ordinary star. When it dies, it will get bigger and become a red giant star. After that it will collapse into a small compact star called a white dwarf,” said Soebur Razzaque from the University of Johannesburg, who led the research.
“But stars that are a lot more massive than the sun play a different end game.”
Such stars instead explode into a supernova, and then leave behind a small compact star known as a neutron star. They are tiny – they could be packed into a space 12 miles across – but are so dense that a spoonful would weigh tons.
Those stars are the originators of the most powerful explosions in the universe. Such explosions affect phone signal today, but also represent a way of peering back into the very beginnings of the cosmos, arriving with us as messengers of the universe when it was in a much younger state.
Related Slideshow: 17 of the coolest space discoveries (Provided by Photo Services)
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Pluto is discovered
On Feb. 18, 1930, astronomer Clyde W. Tombaugh discovered Pluto at the Lowell Observatory in Flagstaff, Arizona, U.S. Named after the Roman god of the underworld, Pluto is about 1,400 miles (2,380 kilometers) wide and takes 248 years to complete one revolution of the sun. It’s temperature of -378 to -396 degrees Fahrenheit (-228 to -238 degrees Celsius) makes Pluto inhospitable. Considered the ninth planet of the solar system at the time of its discovery, Pluto was reclassified as a dwarf planet in 2006 by the International Astronomical Union because its orbit overlapped with that of Neptune’s.
Plasma shield around the heliosphere
When NASA’s space probe Voyager 2 exited the solar system to enter interstellar space, it observed a giant wall of superhot plasma forming a border of what is called the heliosphere. According to scientists, who made the revelation in 2019, the plasma wall separates the solar winds from coming into contact with the interstellar medium. At the same time, the wall, located around 11 billion miles (17.7 billion km) from the sun, protects everything in the solar system from the devastating radiations of the galaxy.
(Pictured) Artist’s impression of NASA’s Voyager 2 spacecraft studying the outer limit of the heliosphere.
Lakes on Titan
In 2006, NASA’s Cassini-Huygens space research mission found lakes of various sizes filled with liquid hydrocarbons on Saturn’s moon, confirming what scientists had long suspected. The discovery made Titan the only body other than Earth with water bodies on its surface. In 2013, the spacecraft collected more data which revealed that Titan also has deep canyons filled with the same liquid. Further, in the last leg of its mission in 2017, Cassini discovered small but deep methane-filled lakes on top of hills in Titan’s northern hemisphere.
Discovery of the first exoplanet
An exoplanet is a celestial body that orbits a star other than our sun. In 1995, astronomers Michel Mayor and Didier Queloz found a planet orbiting 51 Pegasi – a sun-like star in the constellation Pegasus. Quite similar to Jupiter, the planet was named 51 Pegasi b. Its discovery confirmed that the Earth’s sun is not the only one of its kind with a solar system, and heralded an evolution in astronomical research that led to findings of more exoplanets. In 2019, along with James Peebles for his “theoretical discoveries in physical cosmology,” Mayor and Queloz were awarded the Nobel Prize in Physics for their finding. As of Feb. 12, 2020, astronomers have identified 4,116 exoplanets in 3,056 planetary systems.
(Pictured) Artist’s impression of constellation Pegasus.
Exoplanet Kepler-452b
In July 2015, NASA’s Kepler space telescope identified an exoplanet in what is described as the “habitable zone” – an orbital distance from a star where ideal temperatures allow a planet to have liquid water on surface and an atmosphere. Called Kepler-452b, the exoplanet has been described as Earth’s cousin because of its close similarities to our planet and the nature of its star which is similar to that of our sun. In January 2020, NASA’s Transiting Exoplanet Survey Satellite (TESS) discovered an Earth-size planet called TOI 700 d in its star’s habitable zone.
(Pictured) Artist’s rendering of Kepler-452b.
Neutron star smashup
On August 2017, astronomers at the U.S.-based Laser Interferometer Gravitational-wave Observatory (LIGO) and the Europe-based Virgo observed gravitational waves coming from the collision of two massive stars some 130 million light years away. The observation validated Albert Einstein’s 1915 general theory of relativity. It also helped scientists understand that the source of some of the universe’s heavy metals such as gold and uranium are such collisions. The LIGO-Virgo network recorded a similar event again on April 25, 2019.
(Pictured) An illustration released by NASA on Oct. 16, 2017, shows a hot, dense, expanding cloud of debris from two neutron stars before they collided.
Pillars of Creation
In April 1995, NASA’s Hubble Space Telescope captured a breathtaking image – Pillars of Creation. The iconic picture shows three giant gas columns bathed in ultraviolet light from a cluster of young stars in a small region of the Eagle Nebula, or M16. The popular image has since been used in movies, TV shows and on T-shirts, pillows and postage stamps.
Black holes
Although the term was coined by Princeton physicist John Wheeler in 1967, black holes have always been a mystery among space enthusiasts. They are considered to be dead stars that collapse under their own weight. Its gravity pull is so strong that not even light can escape. Consequently, they aren’t visible and they can only be detected by their effect on nearby matter. In April 2019, the Event Horizon Telescope captured the first photograph of a black hole (pictured) at the center of Messier 87 galaxy, located more than 50 million light-years away.
Kepler’s Law
In 1609, German astronomer Johannes Kepler concluded from data collected by Danish astronomer Tycho Brahe that the planets moved around the sun in an elliptical path instead of in circles as it was commonly thought at the time. This was the first of the three laws that Kepler postulated. The revelation helped astronomers predict the motion of the planets more accurately than before.
(Picture) An illustration of the solar system with the paths of the planets.
Mira’s Tail
First spotted by German astronomer David Fabricius in 1596, the bright object Mira (meaning ‘wonderful’ in Latin) was named by German-Polish astronomer Johannes Hevelius in 1662. Lying in the constellation Cetus, the brightness of this star varies for about 11 months. Mira’s changeability pattern was discovered by Frisian astronomer Johannes Holwarda in 1638. In 2007, NASA’s Galaxy Evolution Explorer (GALEX) revealed Mira’s luminous tail of gas that’s more than a dozen light-years long. This is the material that Mira has shed, leaving it behind as it speeds through the galaxy at some 80 miles per second (130 km per second).
Halley’s Comet
Named after English astronomer Edmond Halley, who determined the comet’s periodicity, the object is visible from Earth every 76 years. Captured by several interplanetary spacecraft, the comet is believed to be composed of volatile ice and dust. Leaving a trail of blazing light every time it passes over Earth, Halley’s Comet last appeared in 1986 and will be seen next in 2061.
Discovery of Ceres
Ceres is the largest object in the asteroid belt that lies between the orbits of Mars and Jupiter. Discovered by Italian astronomer Giuseppe Piazzi in 1801, the celestial body was initially considered a comet and then a planet before the discovery of similar objects found in the belt got it reclassified as an asteroid. In 2006, the International Astronomical Union upgraded Ceres to the category of dwarf planet. In February 2017, NASA’s spacecraft Dawn found evidence of organic material on Ceres.
Enceladus and its geysers
NASA’s Cassini probe spotted geyser-like jets of water vapor and other volatile materials blasting from the south pole of the Saturn’s moon Enceladus in 2005. The observation showed that the ice-crusted moon is geologically active, and the discovery that it probably has a subsurface ocean makes it an important target for the search of life elsewhere in the solar system.
Great Red Spot of Jupiter
Found in Jupiter’s southern hemisphere, the spot is a giant, raging storm which is about twice the size of Earth. The unique feature of the storm is that it has been in existence for over 150 years of its observation. It is, however, believed that it was discovered by Italian astronomer Gian Domenico Cassini, who wrote about a “permanent storm” on the planet, in the mid-17th century. According to a research published in the Nature journal in July 2016, the hurricane has wind speeds of 270-425 miles per hour (430-680 kph) on its edges and is responsible for blasting the planet’s upper atmosphere with heat, which is as high as 2,400°F (1,300°C).
Water on Mars
Several interplanetary spacecraft in the past have provided abundant evidence of water on Mars, dating back to NASA’s Mariner 9 mission during the 1970s. The robotic rovers Spirit and Opportunity found initial signs that rocks at one of the Martian craters were exposed to water at one point of time: it may have been a salty lake or an ocean. Findings from NASA’s Mars Reconnaissance Orbiter (MRO) in September 2015 provide the strongest evidence that liquid water might be flowing intermittently on present-day Mars.
Rings of Saturn
Galileo Galilei was the first to observe Saturn in 1610 with a telescope. However, he could not describe the rings. In 1659, Dutch astronomer Christiaan Huygens was the first to theorize that the planet was encircled by rings. Composed of billions of particles of ice and rock, the rings are about 175,000 miles (281,635 kilometers) from the planet but relatively thin — a thickness ranging from about 32 feet (10 meters) to 0.60 miles (1 kilometer).
Discovery of Uranus
Uranus was identified in 1781 by German-British astronomer William Herschel. The “ice giant” gets its bluish surface color from tiny frozen ammonia and methane crystals. The atmosphere is believed to be mostly hydrogen and helium. Scientists at the Kuiper Airborne Observatory discovered rings around the planet in 1977 – making Uranus the second planet with such a feature in the solar system. To date, NASA’s Voyager 2 probe is the only spacecraft to have visited the planet.
17/17 SLIDES
The new research began in April last year – on the morning of 15 April – when a giant flare swept past Mars. A network of satellites including the International Space Station picked it up, triggering the research that is published today.
When GRB 200415A passed Earth, it was not the first such burst to be detected on Earth. But it was unusual in a number of useful ways, including the fact that it came from much closer to us than usual.
It was also the first such giant flare to be picked up since the Fermi gamma-ray space telescope was launched in 2008. That meant that researchers were able to gather vast amounts of data in the 140 miliseconds it lasted, giving them a much better picture of it than the previous visitor that arrived 16 years ago.
And when researchers were able to locate the cause, they found that was unusual too: it came from a magnetar. There are only 30 such known objects in our entire Milky Way, made up of tens of thousands of neutron stars, and they can be a thousand times more magnetic than ordinary neutron stars.
The galaxy from which the flare came is outside our own Milky Way, but only just on the galactic scale. It is a mere 11.4 million light years away.
Because of the work in the time leading up to the blast last year, researchers had built up a detailed set of predictions about what such a GRB might look like when it arrived at Earth. Professor Razzaque had predicted 15 years ago for instance that a giant flare would include two explosions, another closely following the first, and so they were able to compare those predictions with their existing research.
Scientists hope they are able to find yet more, and research them in yet more detail. That could help explain not only the processes that allow for such powerful blasts, but also use them as ways of understanding the story of our cosmos.
“Even though gamma-ray bursts explode from a single star, we can detect them from very early in the history of the universe. Even going back to when the universe was a few hundred million years old,” said Professor Razzaque in a statement.
“That is at an extremely early stage of the evolution of the universe. The stars that died at that time… we are only detecting their gamma-ray bursts now, because light takes time to travel.
“This means that gamma-ray bursts can tell us more about how the universe expands and evolves over time.”