New Astrobites Post: Using Simulations to Predict the Solar Corona

My latest post for Astrobites is now live!

For the paper I covered, I got to relive a little bit of the amazing experience that was the 2017 total solar eclipse (I wrote another blog post about it here). Total solar eclipses provide us with rare opportunities to study parts of the Sun that are otherwise completely outshone – namely, the corona. The authors of the paper used observations of the Sun’s magnetic fields in the weeks leading up to the eclipse to try to predict what the corona would look like on the day of the eclipse – in other words, they were trying to predict space weather!

They did reasonably well, but they also clearly demonstrated that we don’t have nearly enough instruments taking data of the Sun to be able to accurately predict its weather. But we need to be able to do this, because a powerful solar storm has the potential to knock out our satellites, electrical grids, and other various technology we use to survive! With enough advance warning, like that provided by space weather forecasting, we could mitigate the harmful effects of a solar storm.

Day to Night and Back Again: The Great American Eclipse

Just…wow. I feel like I’ve been saying this for the past several years with all of the amazing traveling I’ve been fortunate to do during my physics career, but this was honestly one of the coolest experiences I’ve had. There are simply no words to describe witnessing a total solar eclipse, but I’ll try my best anyway!

I’ve witnessed a couple of partial eclipses in the past, but being present for a total solar eclipse was a top item on my bucket list. I had been anticipating the eclipse of August 21, 2017 for years, and I knew I had to be in the path of totality when the time finally came. Everything seemed to fall perfectly into place within the last few months leading up to the eclipse (and the last year, really) – my boyfriend’s best friend moved to Seattle to take a job at SpaceX, my cousin moved to central Oregon within an hour’s drive of the path of totality, and the eclipse was due to happen within a week of both my and my boyfriend’s birthdays. Honestly, I think the universe would have struck me down if I hadn’t booked a trip to the Pacific Northwest!

Stop #1: Seattle, Washington

My boyfriend and I began our Pacific Northwest tour with four days in Seattle, complete with walking around the city, a baseball game, museums, and hiking. Our Seattle hosts showed us around Pike Place Market during our first afternoon in the city after treating us to a delicious brunch. Afterward, we headed to the Starbucks Roastery (of course I had to get fresh Starbucks coffee in Seattle!). The rest of the day was spent enjoying ice cream and good drinks before heading to a Mariners baseball game. Our weekend concluded with another delicious brunch, a tour of the (outside of the) SpaceX complex in Redmond, WA, and exploring the flight museum.

While our hosts worked during the day on Monday and Tuesday, my boyfriend and I took the opportunity to do some touristy things in Seattle: go up in the Space Needle, walk through the Chihuly Glass Museum, and see the Olympic Sculpture Park. After a 13+ mile day of walking, naturally we then had to do a four-mile hike to Rattlesnake Ledge the following day, in the mountains outside of Seattle. Even though our feet were screaming at us a bit, the hike was definitely worth it and the view from the ledge was fantastic!

Rattlesnake Ledge

Rattlesnake Ledge

We spent a final night with our hosts in Seattle before picking up a rental car and making the 6 hour drive down to Bend, OR, where we would stay with my cousin and prepare for the eclipse!

Stop #2: Bend, Oregon

What better way to spend a couple of days in Bend than touring breweries? Unfortunately, we didn’t get to traverse the infamous “Bend Ale Trail,” though we did check off a few of the breweries on the list during our dinner outings. During our two days in Bend, however, while my cousin and her boyfriend were working, my boyfriend and I took advantage of the endless outdoorsy options for things to do. Our first day was spent hiking in Smith Rock State Park (after sleeping in quite a bit in the morning…). Let me tell you, the Misery Ridge Trail lived up to its name. Luckily we chose to hike the correct direction around the loop – we conquered the bulk of the difficult climbing at the beginning and enjoyed a relatively easy and leisurely hike around the ridge and back down the other side. I definitely would not have wanted to hike in the other direction! Anyway, the views were amazing:

Misery Ridge

Misery Ridge

The first half of our second day in Bend was spent at the Lava Lands National Park, where we toured the awesome site of a volcanic eruption dated to around 7,000 years ago. Even after all that time, there is still hardly anything living in the basalt fields! We then rode a shuttle to the rim of the volcanic cinder cone, where wildlife still existed and the huge, vast expanse of the lava field was visible. Sort of. Unfortunately, smoke from the Milli Wildfire in Sisters, OR had been blown directly over where we were. Not only did the smoke partly conceal what was surely an awesome view, but it also made it hard to breathe. We returned back to Bend to take a nice float down the Deschutes River in a tube, and then it was time to pack for our journey to the path of totality! (…that would make a great movie title!)

In the Path of Totality

The reality of the solar eclipse didn’t truly start to set in for me until the four of us officially set out from Bend on Saturday, August 19th to secure a campsite in the path of totality. I could feel my excitement building up, and that feeling didn’t go away for the subsequent few days. We wound our way through the Oregon high desert, heading north and east out of the smoke cloud emanating from the Milli Wildfire near Bend. Our destination was Hamilton, OR, in honor of my cousin’s and my last names! Unfortunately, Hamilton was quite a bit farther than we originally anticipated, so we stopped early and were fortunate enough to secure one of the last campsites at a county park near Fossil, OR.

After a full week of exploring (for my boyfriend and I) and work (for my cousin and her boyfriend), we were pretty content with relaxing and being disconnected from the busy world outside of our campsite. We spent the subsequent day and a half lying in our hammocks or chatting around the picnic table, with a short break to hike up a nearby hill and scope out our viewing spot for the eclipse. The hike was made considerably more interesting by the fact that it went through a cattle range – the cowpies were practically endless!

We were up and moving bright and early at 8am on August 21st. While the partial phase of the eclipse didn’t start until after 9am and the hike up the hill only took about 20 minutes, I couldn’t wait to get up there! Though, of course, once we were finally at our viewing spot the subsequent hour-long wait was a bit painful…but with eclipse glasses in hand, we started watching the sun for signs of the moon’s shadow.

The Eclipse

During the first third of the partial phase (about 20 minutes), there was practically no difference on Earth aside from the fact that there was a very obvious chunk of the sun missing when viewed through the eclipse glasses. Then, however, the air began to feel a bit cooler and the wind started to pick up. The changing temperature was particularly noticeable in the desert because of the lack of humidity in the air. By the final 20 minutes of the partial phase, it was becoming quite chilly and my eyes could discern a very slight darkening of the world around me. The sensation is difficult to describe – it almost felt as if something was a bit “off” with my eyes, like they weren’t quite working properly. It continued to get cooler as the moon continued to slide over the face of the sun, while the sky remained ever so slightly darker than a bright day.

The last five minutes (read: five minutes!) of the partial phase were incredible, second only to the minute and a half of totality itself. During these five minutes, we could watch the last bit of the crescent sun sliding away (through our glasses, of course). Things began to feel very eery as the world prepared for sunset at 10:30am – in those moments, I completely understood why solar eclipses have the reputation they do in ancient stories. It must have been terrifying to witness the sky darken and the sun blink out in the middle of the day! The sky quickly grew noticeably darker as the temperature continued to drop. In the last moments before totality, we easily spotted Venus shining brightly overhead. I put on my glasses one last time to watch the last sliver of the sun disappear…

The scene that met my eyes when I removed my glasses is burned forever into my memory. The sky had taken on a bluish-black color characteristic of late evening, while the reds and oranges of sunset were visible around the full 360 degrees of the horizon. But most amazing of all was the sun – it was covered completely by the impossibly black disk of the moon, leaving the white, wispy corona to shine brilliantly in a beautiful halo against the blue-black sky. I couldn’t take my eyes away from it.

The total eclipse

View of the landscape during totality


All too soon, a mere 90 seconds later, the famous “diamond ring” reappeared: the sun was returning, with its light overwhelming the corona and the black disk of the moon in a matter of seconds. My cousin, me, and our boyfriends all turned toward each other with expressions of “That was amazing!” written on our faces. To be honest, it was considerably more than “amazing.” I wasn’t kidding when I said there aren’t words to describe it! There is simply no comparison between a total eclipse and a partial eclipse – during a parital eclipse, you never get the drastic darkening of the sky, the experience of seeing stars during the day, the overwhelming excitement caused by knowing what these eery phenomena are leading to, or the image of a black moon surrounded by the brilliant white corona. All I can say is that I will definitely be in the path of totatilty for the next total eclipse in the US in April 2024, and you should be too!