The great geomagnetic storm of August 28 through September 3, 1859 is, arguably, the greatest and most famous space weather event in the last two hundred years.
For the first time observations showed that the sun and aurora were connected and that auroras generated strong ionospheric currents. A significant portion of the world’s 124,000 miles km of telegraph lines were adversely affected, many of which were unusable for 8 hours or more which had a real economic impact.
In addition to published scientific measurements, newspapers, ship logs, and other records of that era provide an untapped wealth of first hand observations giving time and location along with reports of the auroral forms and colors.
At its height, the aurora was described as a blood or deep crimson red that was so bright that one “could read a newspaper by.” At its peak, the Type A red aurora lasted for several hours and was observed to reach extremely low geomagnetic latitudes on August 28–29 (~25°) and on September 2–3 (~18°).” (Green and Boardsen)
On September 1, English astronomer Richard C. Carrington was studying a group of sunspots (through dark filters that protect his eyes, of course). Around 11 am, he saw a sudden flash of intense white light from the area of the sunspots.
Seventeen hours later, the night sky in North America and as far south as Panama in Central America lights up like daytime. It is another wave of even brighter Auroras. People read newspapers by the light. Gold miners in the Rocky Mountains wake up and make coffee, bacon and eggs at 1:00 AM, thinking the Sun has risen on a cloudy morning. (NOAA)
This has been referenced as the Carrington Event, a large solar storm that took place at the beginning of September 1859, just a few months before the solar maximum of 1860.
In August 1859, astronomers around the world watched with fascination as the number of sunspots on the solar disk grew. Among them was Richard Carrington, an amateur skywatcher in a small town called Redhill, near London in England.
On September 1, as Carrington was sketching the sunspots, he was blinded by a sudden flash of light. Carrington described it as a “white light flare” according to NASA spaceflight. The whole event lasted about five minutes.
The flare was a major coronal mass ejection (CME), a burst of magnetized plasma from the sun’s upper atmosphere, the corona. In 17.6 hours, the CME traversed over 90 million miles (150 million km) between the sun and Earth and unleashed its force on our planet. According to NASA spaceflight, it usually takes CMEs multiple days to reach Earth. (Space)
The Advertiser of Sept. 8th, 1859, states: “There was quite a display of the Aurora Borealis a few nights since, visible at Honolulu. Broad fiery streaks shot up into and played among the heavens, almost as beautifully as those which are sometimes seen in more northern climes.”
The Advertiser of September 17th contained the following letter from SE Bishop, dated Lahaina, Sept. 9th. “Your statement that the Aurora was seen in Honolulu enabled me to account for the phenomenon I observed here a few nights since.”
“At 10 PM I noticed a bright, unsteady crimson glow upon the sky, extending from NE to N, and about 35° of altitude. It resembled the reflection of a great conflagration at twenty or thirty miles distance, and I attributed it to heavy fires on the other side of the mountain.”
“I was puzzled however by the fact that the clouds which rested on the mountain did not give the slightest reflection of the supposed fire. Moreover the light was far and rich a crimson to have been caused by a fire.”
“The solar flare of 1 September 1859 was observed and reported by Carrington [1859] and Hodgson [1859] in the Monthly Notices of the Royal Astronomical Society and became the best known solar event of all times.”
“Of particular note was the intensity of the event as quoted in the articles: ‘For the brilliancy was fully equal to that of direct sunlight [Carrington, 1859].’ ‘I was suddenly surprised at the appearance of a very brilliant star of light, much brighter than the sun’s surface, most dazzling to the protected eye …’ [Hodgson, 1859].” (Tsurutani)
“For a few nights before and after this remarkable event, the aurora was intermittently widespread over the globe, in the subauroral and subtropical belts. The period was one of exceptional activity on the sun, as indicated by great sunspots and solar flares.”
“It is interesting to note that the first recorded observation of a solar flare was made visually by Carrington in the forenoon of 1859 September 1.”
“Carrington pointed out that a moderate but very marked magnetic disturbance (which was of the type now known as a crochet) was shown on the Kew magnetograms at the time of observation.”
“Toward four hours after midnight a great magnetic storm commenced. Carrington’s observation is almost unique, for a flare must be of exceptional intensity to be observed in integrated light.” (Chapman in Kimball)
Back then, the telegraph was just about the only communication technology they had. Today, such a storm could severely damage satellites, disable communications by telephone, radio, and TV, and cause electrical blackouts over whole continents. It could takes weeks or longer to fix the damage.
Solar storms like the one in 1859 happen only about every 500 years—thankfully. But smaller storms happen frequently, and storms half as intense as the 1859 storm happen about every 50 years. (NOAA)
