Our sun is “unusually quiet”, according to scientists.
The star in our solar system is very inactive when compared to its galactic counterparts, new research shows.
The latest research used data from the Kepler Space Telescope to compare the brightness of our sun with other similar stars elsewhere in the universe.
According to new research, the sun appears to be less active than those hundreds of similar stars based on brightness variations.
When matched up to 369 solar-like stars, scientists found they typically fluctuated about five times stronger than the Sun over the last 140 years.
However, researchers also studied more than 2,500 Sun-like stars with unknown rotation periods, which showed that their brightness fluctuated much less than that of the other group.
“We were very surprised that most of the Sun-like stars are so much more active than the Sun,” said Dr Alexander Shapiro, from the Max Planck Institute for Solar System Research (MPS).
Scientists narrowed down the first batch of comparable candidates from a vast catalogue of measurement data recorded by Nasa’s Kepler Space Telescope, selecting stars with a similar surface temperature, age and rotation period.
They chose to look at stars that rotate once around their own axis within 20 to 30 days, though it does not determine the rotation period of all the stars, so the team had to consider other factors such as re-appearing dips in the star’s lightcurve.
Previously, scientists have largely relied on recent histories of out star to understand its brightness. Through a range of techniques, we have been able to understand more about its history over the past 9,000 years – but that is a relatively tiny period when compared with the nearly 4.6 billion years the sun has been around.
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Mystic Mountain, a pillar of gas and dust standing at three-light-years tall, bursting with jets of gas flom fledgling stars buried within, was captured by Nasa’s Hubble Space Telelscope in February 2010
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The first ever selfie taken on an alien planet, captured by Nasa’s Curiosity Rover in the early days of its mission to explore Mars in 2012
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Death of a star: This image from Nasa’s Chandra X-ray telescope shows the supernova of Tycho, a star in our Milky Way galaxy
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Arrokoth, the most distant object ever explored, pictured here on 1 January 2019 by a camera on Nasa’s New Horizons spaceraft at a distance of 4.1 billion miles from Earth
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An image of the Large Magellanic Cloud galaxy seen in infrared light by the Herschel Space Observatory in January 2012. Regions of space such as this are where new stars are born from a mixture of elements and cosmic dust
Nasa
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The first ever image of a black hole, captured by the Event Horizon telescope, as part of a global collaboration involving Nasa, and released on 10 April 2019. The image reveals the black hole at the centre of Messier 87, a massive galaxy in the nearby Virgo galaxy cluster. This black hole resides about 54 million light-years from Earth
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Pluto, as pictured by Nasa’s New Horizons spacecraft as it flew over the dwarf planet for the first time ever in July 2015
Nasa/APL/SwRI
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A coronal mass ejection as seen by the Chandra Observatory in 2019. This is the first time that Chandra has detected this phenomenon from a star other than the Sun
Nasa
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Dark, narrow, 100 meter-long streaks running downhill on the surface Mars were believed to be evidence of contemporary flowing water. It has since been suggested that they may instead be formed by flowing sand
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Morning Aurora: Nasa astronaut Scott Kelly captured this photograph of the green lights of the aurora from the International Space Station in October 2015
Nasa/Scott Kelly
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Mystic Mountain, a pillar of gas and dust standing at three-light-years tall, bursting with jets of gas flom fledgling stars buried within, was captured by Nasa’s Hubble Space Telelscope in February 2010
Nasa/ESA/STScI
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The first ever selfie taken on an alien planet, captured by Nasa’s Curiosity Rover in the early days of its mission to explore Mars in 2012
Nasa/JPL-Caltech/MSSS
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Death of a star: This image from Nasa’s Chandra X-ray telescope shows the supernova of Tycho, a star in our Milky Way galaxy
Nasa
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Arrokoth, the most distant object ever explored, pictured here on 1 January 2019 by a camera on Nasa’s New Horizons spaceraft at a distance of 4.1 billion miles from Earth
Getty
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An image of the Large Magellanic Cloud galaxy seen in infrared light by the Herschel Space Observatory in January 2012. Regions of space such as this are where new stars are born from a mixture of elements and cosmic dust
Nasa
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The first ever image of a black hole, captured by the Event Horizon telescope, as part of a global collaboration involving Nasa, and released on 10 April 2019. The image reveals the black hole at the centre of Messier 87, a massive galaxy in the nearby Virgo galaxy cluster. This black hole resides about 54 million light-years from Earth
Getty
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Pluto, as pictured by Nasa’s New Horizons spacecraft as it flew over the dwarf planet for the first time ever in July 2015
Nasa/APL/SwRI
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A coronal mass ejection as seen by the Chandra Observatory in 2019. This is the first time that Chandra has detected this phenomenon from a star other than the Sun
Nasa
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Dark, narrow, 100 meter-long streaks running downhill on the surface Mars were believed to be evidence of contemporary flowing water. It has since been suggested that they may instead be formed by flowing sand
Nasa/JPL/University of Arizona
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Morning Aurora: Nasa astronaut Scott Kelly captured this photograph of the green lights of the aurora from the International Space Station in October 2015
Nasa/Scott Kelly
The new study allowed the reserchers to instead compare our star with its other counterparts, helping give a better picture of how normal its behaviour is. And scientists are still unclear about why exactly it is so unusual.
“It is conceivable that the Sun has been going through a quiet phase for thousands of years and that we therefore have a distorted picture of our star,” explained Dr Timo Reinhold, first author of the new study, who published the findings in the Science journal.
The scientists behind the research note that it is possible that the Sun can have higher variability over long timescales, or differs from similar stars in ways that haven’t yet been recognised.
Additional reporting by Press Association
