Space Weather Prediction Center
Monday, 22 October 2018
Deon Combs glanced up at his computer monitor at the little patch of black and gray surrounded by bright yellow. It was a computer rendering of the Sun. The little black patch was right on the edge of the visible solar disk, and about to rotate out of sight, at least for the next 13 to 14 days. The reminder of the Sun was pure, clean, bright yellow. Not another blemish in sight.
Deon worked at the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center. He was a space weather forecaster.
Deon had been pondering that little black patch for several days. Now that it was sliding out of view he hoped it would still be there two weeks later when that region rotated back around the Sun’s other side. If it was still there in two weeks, his confidence would take a huge jump.
Deon had a theory; a strong hunch he was keeping to himself for the time being. On three previous rotations there had been a spot in that same part of the Sun’s surface. Now it had lasted though the fourth transit, and he was struggling with what inferences he dare draw from what appeared to be the dogged persistence of one active region.
Every time a sunspot forms on the Sun or rotates around its edge into view, it is given a serial number. If the same region rotates out of view and then back into view two weeks later, it gets a new number. This disappearing active region was numbered 13200, and — Deon believed — had had former numbers of 13179, 13166, and 13158. If still existed in two weeks’ time it would be given yet a fifth serial number. Deon considered it to be the same beast, albeit a relatively small beast.
Growing up in Detroit, Deon was interested in science from the time his father took him into the recording studio where he worked. Deon was fascinated with the way sound moved and was captured on reels of tape. He decided as a young boy that he wanted to work in the field of sound engineering or electronics. With his family unable afford college, Deon’s interests led him to apply to the United States Air Force in the hope of getting a technical trade involving electronics of some sort.
After aptitude testing, Deon was offered the trade of Geospatial Analyst, which involved receiving and interpreting images to identify items of interest to military intelligence and tactical staff. He started as an Airman First Class, and worked hard to perfect himself in his trade. Soon, his superiors noticed that he had the ability to see patterns and shapes that others could not. Deon’s uncanny ability to pick out targets, camouflaged buildings, hidden aircraft and artillery made him a much-sought-after analyst.
Soon, Deon was offered a SOAR award (“scholarship for an outstanding airman”) to attend college and get his degree. He chose geomatics, and upon return to the Air Force, he was commissioned and worked as an officer. His duties included a temporary assignment to the Air Force Academy to assist with research and instruction in Geospatial Intelligence.
It was on a field orientation trip with one of his classes from the Academy that Deon first visited the Space Weather Prediction Center up the road in Boulder. Later, when it came time to decide whether to re-engage for another five years or leave the military for a quieter life, Deon approached the SWPC to see if there were any openings. With a spate of recent retirements, there were; and Deon made the transition to civilian life as a solar forecaster. As he was about to discover, his new career was not a quieter life at all.
During his study of the Sun, Deon was particularly taken with the lifespan of sunspots. Most last just a day, or even less. Some persist for several days and — rarely — still others can last for a month. But Deon had a hunch that the solar conditions favoring the formation of sunspots — even if they appeared to be random — could eventually produce a sunspot that could last for months. And, with this particular active region, Deon figured he was watching the first real live one of his short career.
Deon’s theory had been incubating in his mind for some time. The sun is a machine, he thought, and machines can be analyzed and understood as mechanical devices, and not just random forces of nature. In his spare time, and when he was assigned to the research desk at the SWPC, Deon pored over decades of solar data — looking for patterns that nobody else had seen. His theory, starting to gel after three years at the forecast center, was that there was a massive internal magnetic field or some other force that was invisible — except when its own rotation brought it close to the Sun’s surface. He figured if he worked hard enough at cataloging and linking past events, he would eventually be able to predict the rotation of this internal field. For the time being, he kept the work to himself.
It was almost time for the morning briefing, and Deon was still thinking about whether to make the suggestion that there was something unusual about this particular active region on the Sun. The Sun does not have a solid surface, so it is more art than science to pinpoint the same zone each time it rotates into view. Deon was working on how to identify unique magnetic signatures in active regions so they could be confirmed as persistent — even if they disappeared for two weeks at a time around the back side of the Sun.
There were two main workstations at the forecast office; staffed around the clock. One forecaster sat on the left of the office and analyzed the data coming in from the Sun. That forecaster also kept in close touch with the forecast center’s main clients such as NASA and the US military. The other forecaster, seated on the right of the office, was responsible for verifying the incoming data, and generating the office’s published products to the wider world. Alerts, warnings, watches and routine messages originated with the right-seat forecaster.
On this shift, Deon was seated on the left and was on data analysis. As the Sun was mostly quiet — near this lull in activity that comes regularly every 11 years — Deon had to spend less time talking to clients and had more time to pursue his own research. But, for the time being, it was only a theory. Humanity still knew very little about why the Sun behaved as it did. New theories and ideas were being proposed regularly, but there was still only a vague consensus about the broader strokes. Deon’s thinking was, for now, likely just more flotsam in a sea of ideas.
At the 0910 briefing it was Deon’s responsibility, as the left-side forecaster this week, to present the current picture of the Sun and Earth to an assembly of staff at the Center. Since shift change that morning at 0600 Deon had been preparing the slides that would form the background of his briefing. With just a few minutes to spare, Deon saved the slide package to his computer and stood.
“Good morning, everyone,” Deon opened. “Here is the situation today. The only active region is #13200, and we expect it will have rotated around the east limb by the end of the day. The remainder of the solar disk is clear of any visible sunspots, although there are some bumps in the 2800 MHz radio flux data that do not correlate well with what we are seeing in the visual range. There have been no CMEs and no flares on imagery. The few pores we do see are widely dispersed and we do not think they will coalesce for at least the next several days. We should continue spot-free unless something rotates into view and surprises us. Right now our peek around the edge of the limb reveals nothing of concern.”
As Deon spoke an image of the Sun lit up behind him, with departing sunspot 13200 on the very edge of visibility. Then, a graph of the 2800 MHz flux strength appeared.
“We expect the next three days will deliver quiet conditions, although the geomagnetic field has been unsettled to active in the last six hours. We believe this is due to the overall increase in solar wind speed from a few small coronal holes. We have a higher proton and electron flux than we did in yesterday’s briefing, but we do not think this will increase much further.”
With that, the briefing wrapped up and the staff went back to their posts. The researchers returned to their computer models in the Spaceweather Prediction Testbed. Administrative and technical staff began to build the day’s briefing into a published forecast. The Air Force liaison phoned his operations center with the daily update from his perspective. The right seat forecaster — this week it was Priya Bannerjee — picked up the phone, pressed a few keys, and started her recorded message:
“Solar-terrestrial indices for 22 October follow. Solar flux 83 and estimated planetary A-index 9. The estimated planetary K-index at 1500 UTC on 22 October was 1. No space weather storms were observed for the past 24 hours. No space weather storms are predicted for the next 24 hours.”
Priya hung up the phone. “Deon, you looked like you had more that you wanted to say during the briefing. What’s on your mind?”
“I think region 3200 is actually the same region that we saw as 13179, 13166, and 13158,” replied Deon. “I think it’s recurring but I’m not sure of it, and I’m not sure if it really makes any difference. But if it is recurring it may validate a theory I’m working on for longer term forecasting.”
“Interesting,” said Priya. “Do you think it’s going to be back in 14 days?”
“Yes, I do, and if my theory is right it may give us a little trouble the next time by.”
“Really? The sun is so quiet lately. I can’t remember what a good CME looks like.”
Priya was fibbing, and Deon knew it. She knew exactly what a Coronal Mass Ejection looked like. Frightening, wild, explosive, deadly. A “good” CME was violent, but harmless, as only the ones pointed at Earth posed any danger. The chances of an Earth-directed CME were always slim, because Earth was tiny and the Sun’s reach was vast.
“Well, we may see a CME out of this next rotation,” replied Deon. “If we do, I’ll be ready to be a little more bold about my theory.”