Tau Boötis pole flip
March 13, 2008. On this date, a faint star within the constellation Boötes the Herdsman went down in astronomical historical past. That’s the date astronomers revealed a examine of the star Tau Boötis, displaying it flipped its north and south magnetic poles. These astronomers had been engaged in mapping the magnetic fields of stars. However Tau Boötis was the primary star, aside from our sun, that they noticed endure a magnetic reversal. The peer-reviewed journal Month-to-month Notices of the Royal Astronomical Society revealed the study.
Afterward, astronomers intently watched Tau Boötis for extra magnetic turnovers. They found that this star undergoes magnetic reversals in durations of about two years. That’s in distinction to our sun, which undergoes a magnetic reversal about each 11 years. Learn extra in regards to the sun’s magnetic reversals beneath.
Though it’s not a brilliant star, you’ll be able to see Tau Boötis for your self. It’s close to the blazing yellow-orange star Arcturus, brightest star in your jap sky in on spring evenings from the Northern Hemisphere. To confirm that you simply’re taking a look at Arcturus, search for the Huge Dipper up excessive in your northern sky. Follow the arc of the Huge Dipper’s deal with to Arcturus. Tau Boötis is a few 70 occasions fainter than Arcturus. You’ll see its location on the chart beneath.
Last chance to get a moon phase calendar! Only a few left. On sale now.
Our sun’s magnetic fields
Now, about our sun’s magnetic reversals. As we mentioned above, the sun’s magnetic polarity flips roughly each 11 years. Magnetic reversals are a part of our sun’s regular exercise, and – as proven by Tau Boötis in 2008 – it’s doubtless different stars just like our sun within the Milky Way galaxy (and different galaxies) additionally endure magnetic reversals.
The YouTube video beneath is from December 2013, when the solar cycle was close to its peak. It options solar astrophysicist Alex Young, speaking about Photo voltaic Cycle 24 and about what a magnetic flip means for Earth. You may get day by day updates on our sun’s exercise from Alex here.
Magnetic subject flip video
Now take a look at one other cool video, beneath. It’s from NASA’s Goddard Area Flight Heart and is a visualization, displaying the place of the sun’s magnetic fields from January 1997 to December 2013. Magenta strains present the place the sun’s total subject is adverse, and the inexperienced strains present the place it’s optimistic. A area with extra electrons is adverse, the area with much less is optimistic. Further grey strains symbolize areas of native magnetic variation.
The visualization exhibits how, in 1997, the sun confirmed optimistic polarity on the highest and adverse polarity on the underside. Over the following 12 years, every set of strains creeps towards the alternative pole, finally displaying a whole flip.
Enjoyable to assume that different stars (most certainly) do that, too!
Backside line: On March 13, 2008, astronomers revealed the primary examine displaying that the star Tau Boötis skilled a pole flip. That’s a magnetic reversal, which is one thing we had beforehand solely seen on the sun.
Source: Magnetic cycles of the planet-hosting star Tau Boötis
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
