One advantage of a relatively quite Sun, such as now, is that weak geomagnetic events can be detected that would otherwise be missed in the maelstrom of geomagnetic activity resulting from an active Sun. The magnetic impulse of a CIR (Co-rotating Interaction Region) is one such event recently detected on my magnetometer.
A CIR represents the boundary between 'regular' solar wind and faster flowing solar wind from a coronal hole. https://ase.tufts.edu/cosmos/view_picture.asp?id=125. At the boundary between plasma travelling at different speeds, the interplanetary magnetic field is compressed and intensified and this creates geoeffective magnetic disturbances in our local magnetic field, when the region reaches Earth, that can be detected by magnetometers at ground level.
Here are my data from my magnetometer here in the UK, illustrating when the CIR struck.
This shows good correlation with NOAA data from the DSCOVR satellite located upwind at the L1 Lagrange point at a distance of 1.5 million km towards the Sun. At the time the impulse reached the satellite, the average solar wind speed was around 350-400 km/s, meaning an approximate 1-2 hr delay between the DSCOVR readings and the impulse reaching Earth.
NOAA Data from DSCOVR satellite.
This weak event didn't spark any geomagnetic storms or aurorae, but it was interesting to see the wiggles on my magnetometer bearing witness to the event.
Thanks for looking.
Stu.
Co-rotating Interaction Region (CIR) Detection
- Carbon60
- Way More Fun to Share It!!
- Posts: 14314
- Joined: Wed Mar 07, 2012 12:33 pm
- Location: Lancashire, UK
- Has thanked: 8559 times
- Been thanked: 8291 times
Co-rotating Interaction Region (CIR) Detection
H-alpha, WL and Ca II K imaging kit for various image scales.
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
- Montana
- Librarian
- Posts: 34722
- Joined: Mon Oct 17, 2011 5:25 pm
- Location: Cheshire, UK
- Has thanked: 17974 times
- Been thanked: 8906 times
Re: Co-rotating Interaction Region (CIR) Detection
Great data Stu, and always nice to see it verified from other sources
Alexandra
Alexandra
- marktownley
- Librarian
- Posts: 42550
- Joined: Tue Oct 18, 2011 5:27 pm
- Location: Brierley Hills, UK
- Has thanked: 20819 times
- Been thanked: 10489 times
- Contact:
Re: Co-rotating Interaction Region (CIR) Detection
Great data Stu! I will be keeping an eye open for your updates when we're in Iceland next month.
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
- Carbon60
- Way More Fun to Share It!!
- Posts: 14314
- Joined: Wed Mar 07, 2012 12:33 pm
- Location: Lancashire, UK
- Has thanked: 8559 times
- Been thanked: 8291 times
Re: Co-rotating Interaction Region (CIR) Detection
Many thanks, Alexandra/Mark. I always appreciate your feedback.
Let me know when you're in Iceland, Mark, and I'll aim to make a special set of geomag reports for you.
Stu.
Let me know when you're in Iceland, Mark, and I'll aim to make a special set of geomag reports for you.
Stu.
H-alpha, WL and Ca II K imaging kit for various image scales.
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
-
- Way More Fun to Share It!!
- Posts: 2033
- Joined: Sat Nov 24, 2012 2:33 pm
- Has thanked: 57 times
- Been thanked: 1204 times