A brand-new study has identified a close-by star whose sunspot cycles appear to have stopped. When our sun paused its sunspot cycles, studying this star might help discuss the duration from the mid 1600s to the early 1700s. This image portrays a common 11-year cycle on the sun, with the least sunspots appearing at its minimum (leading left and leading right) and the most appearing at its optimum (center). Credit: NASA
The number of sunspots on our sun usually ups and downs in a foreseeable 11-year cycle, but one uncommon 70-year period when sunspots were exceptionally unusual has actually mystified researchers for 300 years. Now a close-by sun-like star seems to have paused its own cycles and got in a similar period of uncommon starspots, according to a team of researchers at Penn State. Continuing to observe this star could assist explain what occurred to our own sun throughout this “Maunder Minimum” along with provide insight into the suns excellent magnetic activity, which can interfere with satellites and worldwide communications and perhaps even affect environment on Earth.
The star– and a brochure of 5 decades of starspot activity of 58 other sun-like stars– is described in a new paper that appears online in the Astronomical Journal.
Starspots appear as a dark area on a stars surface area due to momentary lower temperatures in the location resulting from the stars eager beaver– the process that creates its electromagnetic field. Astronomers have been documenting modifications in starspot frequency on our sun since they were very first observed by Galileo and other astronomers in the 1600s, so there is a good record of its 11-year cycle. The exception is the Maunder Minimum, which lasted from the mid-1600s to early 1700s and has actually perplexed astronomers ever given that.
A new study has identified a nearby star whose sunspot cycles appear to have actually stopped. Studying this star might assist discuss the duration from the mid 1600s to the early 1700s when our sun paused its sunspot cycles. Starspots appear as a dark spot on a stars surface due to short-term lower temperatures in the location resulting from the stars dynamo– the procedure that creates its magnetic field. The group recognized or confirmed that 29 of these stars have starspot cycles by observing at least 2 complete durations of cycles, which often last more than a decade.” When we first saw this data, we believed it should have been a mistake, that we pulled together information from two different stars or there was a typo in the star or the brochure was misidentified,” said Jacob Luhn, a graduate trainee at Penn State when the project began who is now at the University of California, Irvine.
” We do not truly understand what triggered the Maunder Minimum, and we have actually been looking to other sun-like stars to see if they can offer some insight,” said Anna Baum, an undergrad at Penn State at the time of the research and first author of the paper. “We have actually identified a star that our company believe has actually gotten in a state similar to the Maunder Minimum. It will be actually exciting to continue to observe this star throughout, and ideally as it comes out of, this minimum, which could be extremely helpful about the suns activity 300 years ago.”
The research study group pulled data from several sources to sew together 50 to 60 years of starspot data for 59 stars. The scientists assembled a database of stars that appeared in both sources and that had other readily available info that may help describe starspot activity.
The group validated or determined that 29 of these stars have starspot cycles by observing a minimum of two full durations of cycles, which frequently last more than a years. Some stars did not appear to have cycles at all, which could be since they are turning too gradually to have an eager beaver and are magnetically “dead” or because they are near the end of their lives. Several of the stars require additional study to validate whether they have a cycle.
” This constant, more than 50-year time series permits us to see things that we never ever would have noticed from the 10-year photos that we were doing previously,” said Jason Wright, professor of astronomy and astrophysics at Penn State and an author of the paper. “Excitingly, Anna has actually found an appealing star that was cycling for decades but appears to have stopped.”
According to the scientists, the star– called HD 166620– was approximated to have a cycle of about 17 years but has actually now gone into a duration of low activity and has actually shown no signs of starspots because 2003.
Sunspots were first observed in the 1600s by using a customized telescope called a helioscope. The instrument tasks a picture of the sun onto a surface, where dark sunspots can be observed. This illustration was produced by Christoph Scheiner in the 1600s for his book “Rosa Ursina sive Sol.” Credit: Christoph Scheiner
” When we initially saw this information, we believed it needs to have been an error, that we pulled together information from two different stars or there was a typo in the star or the catalog was misidentified,” stated Jacob Luhn, a graduate student at Penn State when the task began who is now at the University of California, Irvine. And there arent that numerous bright stars in the sky that Mount Wilson observed.
The scientists want to continue studying this star throughout its minimum duration and potentially as it comes out of its minimum and starts to cycle as soon as again. This continued observation could supply important information about how the sun and stars like it create their magnetic eager beavers.
” Theres a huge dispute about what the Maunder Minimum was,” said Baum, who is now a doctoral trainee at Lehigh University studying excellent astronomy and asteroseismology. “Did the suns magnetic field generally turn off? Did it lose its eager beaver? Or was it still biking however at a really low level that didnt produce numerous sunspots? We cant go back in time to take measurements of what it was like, however if we can characterize the magnetic structure and magnetic field strength of this star, we might begin to get some responses.”
It has also been suggested that sunspot cycles might have a connection to environment on Earth. In addition, the researchers said that information from this star might affect our search for planets beyond our solar system.
” Starspots and other kinds of surface area magnetic activity of stars hinder our capability to spot the planets around them,” stated Howard Isaacson, a research study scientist at the University of California, Berkeley, and an author of the paper. “Improving our understanding of a stars magnetic activity may help us enhance our detection efforts.”
The curated database of the 59 stars and their starspot activity from this research has actually been made available for researchers to even more examine.
” This research is a great example of cross-generational astronomy, and how we continue to improve our understanding of deep space by constructing upon the many observations and dedicated research study of astronomers that came prior to us,” said Wright. “I took a look at starspot information from Mount Wilson and Keck Observatory for my thesis when I was a graduate trainee, Howard looked at starspot data from the California Planet Survey for his masters thesis, and now Anna has actually stitched together all the information for a more extensive look across the years. We are all delighted to continue studying this and other promising stars.”
Reference: “Five Decades of Chromospheric Activity in 59 Sun-like Stars and New Maunder Minimum Candidate HD 166620” by Anna C. Baum, Jason T. Wright, Jacob K. Luhn and Howard Isaacson, 22 March 2022, Astronomical Journal.DOI: 10.3847/ 1538-3881/ ac5683.
