Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 31/08/2026Trying to find a PDF of an older paper online. I tried google scholar first, and hit a complete wall. Tried a regular google search, and did not get anything that actually took me to the paper. Switched to Kagi, a newer, freemium search engine. Literally the first hit was *the* PDF I needed. 120
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/07/2026The work that @drbwalsh.bsky.social and I did to develop a concept for stopping space weather is now **front page** on the Wall Street Journal. It's been a wild week. 1122
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 05/06/2026Storm has arrived super late. Not super fast, but strong magnetic field. Bz is jumping up and down. Kp sitting around 6. The timing **sucks** for North America. 120
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/04/2026Here's the same thing but funnier. 35-ish years of auroral electrojet data as measured on the ground... 000
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/04/2026I just downloaded 35 years of SuperMAG electrojet index data for reasons. 100
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 04/02/2026Shocking contrast between the solar wind density values observed by IMAP versus ACE- as much as 20 times higher in the new IMAP versus the very old ACE!!! We know ACE is getting old, but holy smokes that's a staggering difference. 230
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 19/01/2026Seeing all these aurora pics from Europe... 030
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 06/01/2026Not a bad year for running off stress. strava.app.link/CFs81zq5HZb 000
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 05/01/2026aaaaaaaaaaaaaaaAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH 010
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 14/12/2025How do you get ready for #FallAGU in 2025? By printing ICE whistles, of course. 110
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 05/12/2025It is all-the-way winter in Michigan. 010
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 03/12/2025Copy-pasting @sciguyspace.bsky.social's post from TheBadSite to spread the message here. I entirely agree with Eric's second point: the space community has been suffering from the lack of stable leadership at NASA. [cont'd] 110
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 27/11/2025Happy Thanksgiving! Gotta calm the nerves during halftime #GoLions 140
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 12/11/2025I wish I could take credit for this, but yeah nuttin' but clouds up here in MI #NoAurora #Sad #WeatherCanEatMyButt 050
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 12/11/2025So what does SWPC do? They switch to DSCOVR! DSCOVR's plasma instrument is also suspect, often yielding WILD oscillations that are not accurate. That's happening right now! See my annotations in the plot below. You can see when SWPC switches to DSCOVR and when DSCOVR goes nuts. 130
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 12/11/2025...breaking this down: this is ACE real time data. The plasma instrument, SWEPAM, is very old. Under strong conditions, the instrument can not give good, clean data. We can see the precise moment where SWEPAM stops operating accurately in the orange, yellow, and green lines below. 110
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 08/09/2025Hell yeah the first talk at an IEEE meeting is about space weather. 050
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 02/09/2025Very unfortunate storm in the end. The magnetic field of the storm was predominantly northward- meaning it could not effectively transmit energy to the Earth system, preventing the aurora from moving southward. BOOOO! 181
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 30/08/2025Today was a good day. for running. 020
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 14/07/2025Holy crap twitter sucks rocks. 100
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 02/05/2025Parkrun, Dunedin Botanical Gardens! It's a beautiful fall morning here in southern NZ! 040
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 11/10/2024I had a foggy pre dawn run in the old part of Bern- the perfect run for SpOoKy season! 010
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 27/09/2024Bluesky now has over 10 million users, and I was #780,667! Huzzah. Excelsior. 020
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 15/05/2024The biggest solar storms in terms of well-known space weather effects are the 1989 HydroQuebec event, the 2003 Halloween storm, and now, the Gannon Storm of 2024. How do they compare? We can quantify that with the Dst Index (lower numbers = stronger storm) 150
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/05/2024The solar storm so far has been great. Dayside magnetopause pushed well within geosynch (via GOES data). <-200nT Dst (SWPC Geospace & USGS real time data). Auroral Electrojet index (AE) well above 2000nT (Kyoto WDC data). In a short amount of time, there's being a lot going on! 031
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/05/2024Wake up, babe. New solar storm just dropped. #spaceweather #aurora #sun #space 020
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/05/2024It's... happening??? www.swpc.noaa.gov/news/swpc-is... 100
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 06/05/2024This solar cycle continues to put out moderate after moderate storm. Nice on happening right now! Still waiting for a BIG ONE, however. We want to see Dst go below -200nT! 100
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 06/04/2024OUR 3-DAY-AHEAD FORECAST IS LIVE FOR THE ECLIPSE! These images show 4 forecasts of what the corona will look like if you're in Dallas, Texas! More details here: clasp.engin.umich.edu/solar-eclips... #EclipseSolar #Eclipse #Eclipse2024 022
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 25/03/2024What's cool about the current event is that it was a series of events, each with increasing magnitude (see the red/white line at the bottom of this plot). These types of compound events are super interesting for understanding how the Earth response depends on previous, recent activity. 000
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 25/03/2024A series of small/medium storms followed by a "big" one! The timing was bad for North American aurora watchers, but this will be a great storm to study in the future. What we're still missing are the BIG storms of <-250nT Dst that were seen in the early 2000s. Hopefully soon... 110
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 03/03/2024I'm late to the party, but solar storm ahoy! It's a moderate storm that's slow moving but with a strong, southward magnetic field sure to drive aurora at higher latitudes. If it's dark where you are, take a peek outside! 010
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 23/02/2024Back from the blue team review of our mission concept study for MAAX, a two-spacecraft mission to view both the aurora borealis and australis at the same time. We're making great progress and are on track for delivering a high-quality concept report to NASA in August! 020
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 23/02/2024Here's a first for me: landed in fifth so dense that our plane has to get a tow into the gate. 100
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 10/02/2024Hello, Yogost. Uh, I'm good thanks. 110
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 07/12/2023Not messing around with these stickers. 031
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 06/12/2023If you're at #FallAGU this year, be sure to grab a MAAX sticker from yours truly. 011
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 01/12/2023Another good space weather storm last night! - The magnetic field in the solar wind went down to -20nT, producing great aurora. - Dst (bottom line) got down to -150nT, indicating a nice strong response at Earth. - It was a twofer: two CME arrivals creating a weak then strong storm. 120
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 26/11/2023We've been getting a steady diet of small-to-medium sized solar storms, driving aurora at higher latitudes. Reports of aurora near mid-latitudes, too! These have been storms with persistent "southward IMF" (red line in top plot is negative). 100
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 07/11/2023I'm on a hybrid meeting (40 people online, ~30 in person). Lunch for in-person people is late in arriving, so we're just continuing with presentations. We're just plowing ahead, unabated. There's no sign of lunch. 120
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 06/11/2023Last night's storm was officially a good one! Lots of aurora, Dst well below -100nT (both observed and modeled), STRONG southward interplanetary magnetic field... This is going to be an event that is studied in the near future. Thanks, solar maximum! 000
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 24/10/2023I think I need a clarification concerning the presentation I will be giving. 110
Prof. Dr. Dan guy -issimo. @spacecataz1663.bsky.social · 06/10/2023looool oh yeah this is from Feb. It's still there. 010