Spaceweather.com reports that today we surpassed the largest number of spotless days (270) of the previous 2008 Solar Minimum cycle. The current spotless streak stands at 33 days and is quite possibly on its way to surpass the previous longest streak of this minimum at 36 days. And you have to go back to 1913 to find a year that had more spotless days (311)!
Above: The blank sun on Dec. 8, 2019. Credit: NASA/Solar Dynamics Observatory
The bad news: the Solar Minimum could deepen as many scientists have calculated minimum may not occur until April 2020. You might be wondering: when is the next Solar Maximum? That’s forecast to be July 2025. Both the minimum & maximum forecasts have a +/- 6-month error.
How has the historic Solar Minimum impacted your radio listening? I know it’s impacted my motivation to set-up my solar telescope for solar observation.
ONE WEEK FROM A SPACE AGE RECORD: 2019 is about to set a Space Age record. So far this year, the sun has been blank (no sunspots) for 261 days, including the last 24 days in a row. If the streak continues for only 7 more days, 2019 will break the Space Age record for spotless suns.
The previous record-holder is the year 2008, when the sun was blank for 268 out of 365 days, making the Solar Minimum of 2008-2009 the deepest of the Space Age. Next weekend, barring a sudden profusion of sunspots, 2019 will move into first place.
Solar Minimum is a normal part of the 11-year sunspot cycle. The past two (2008-2009 and 2018-2019) have been long and deep, making them “century-class” Minima. To find a year with more blank suns, you have to go back to 1913, which had 311 spotless days.
What are the side-effects of Solar Minimum? On one hand, solar flares and geomagnetic storms subside, making it harder to catch Northern Lights at mid-latitudes. Space weather grows “quiet.” On the other hand, cosmic rays intensify. The sun’s weakening magnetic field allows more particles from deep space into the solar system, boosting radiation levels in Earth’s atmosphere. Indeed, this is happening right now with cosmic rays nearing a Space Age record.
Stay tuned for updates this week!
As an avid amateur astronomer, solar observation has been quite boring during 2018. As a shortwave radio enthusiast, the lack of solar activity has impacted that hobby as well.
Well, the catchword of the day is “surprise”!
I was alerted yesterday evening by Spaceweather.com that a large sunspot had emerged and developed into a group – with the two main sunspots’ diameter about as large as the earth.
Credit: Spaceweather.com – Sunspot group AR2720, photographed by Thierry Legault on Aug. 25th from the Saint-Véran/Astroqueyras observatory in the French Alps. An image of Earth has been inserted for scale (Link).
Another overnight email notification from Spaceweather.com stated a “surprise” G-3 Class Geomagnetic storm is underway (now!) caused by a coronal mass ejection.
Credit: Spaceweather.com – According to a NOAA computer model, almost 80 billion watts of power surged through Earth’s auroral oval during today’s geomagnetic storm (This image/forecast is updated every 30-minutes at this link).
Has this “surprise” impacted your radio weekend? I know it has impacted my astronomy weekend … I’ll be out there, soon, setting up my solar telescope to view today’s show in hydrogen-alpha!
Edit: Yes indeed, even excluding the sunspots the solar disc yielded more surface detail today via my H-alpha solar telescope than I’ve seen all year – as well as several nice solar prominences along the limb. I encourage anyone who has the proper telescope AND proper filters to take a look at ‘Ole Sol today (and hopefully for the next several days). I’ll have to check the shortwaves later.
Sunspots are becoming scarce. Very scarce. So far in 2018 the sun has been blank almost 60% of the time, with whole weeks going by without sunspots. Today’s sun, shown here in an image [above] from NASA’s Solar Dynamics Observatory, is typical of the featureless solar disk.
The fact that sunspots are vanishing comes as no surprise. Forecasters have been saying for years that this would happen as the current solar cycle (“solar cycle 24”) comes to an end. The surprise is how fast.
“Solar cycle 24 is declining more quickly than forecast,” stated NOAA’s Space Weather Prediction Center on April 26th. This plot shows observed sunspot numbers in blue vs. the official forecast in red:
“The smoothed, predicted sunspot number for April-May 2018 is about 15,” says NOAA. “However, the actual monthly values have been lower.”
The Sun has likely already entered into a new unpredicted long-term phase of its evolution as a hydrogen-burning main sequence star — one characterized by magnetic sputtering indicative of a more quiescent middle-age. Or so say the authors of a new paper submitted to The Astrophysical Journal Letters.
Using observations of other sunlike stars made by NASA ’s Kepler Space Telescope, the team found that the Sun is currently in a special phase of its magnetic evolution.
At time of posting (June 28, 2016) the Sun has no Sun spots at all, which means very low solar activity. Credit: SDO/HMI (Click to enlarge)
Heretofore, the Sun was thought to have been just a more slowly rotating version of a normal yellow dwarf (G-spectral type) star. These results offer the first real confirmation that the Sun is in the process of crossing into its magnetic middle age, where its 11-year Sunspot cycles are likely to slowly disappear entirely. That is, from here on out, the Sun is likely to have fewer sunspots than during the first half of its estimated 10 billion year life as a hydrogen-burning star.
“The Sun’s 11-year sunspot cycle is likely to disappear entirely, not just get less pronounced; [since] other stars with similar rotation rates show no sunspot cycles,” Travis Metcalfe, the paper’s lead author and an astronomer at the Space Science Institute in Boulder, Colo., told me.[…]
Sunspots of September 1, 1859, as sketched by Richard Carrington A and B mark the initial positions of an intensely bright event, which moved over the course of 5 minutes to C and D before disappearing. (Source: Wikimedia Commons)
These days, CMEs and solar flares get a great deal of media attention. But it’s mostly speculation–for even with our advanced abilities to measure the potential impact, we can’t be sure what will happen each time this occurs. Might this solar flare be strong enough to damage our satellites and electrical infrastructure? we may wonder. Could it ‘fry’ our electrical grid?
The concerns are merely speculative. But is there actual cause for concern? Surely. A massive solar flare could damage much of our technology in space–such as our satellites–and could also certainly cause headaches for those who manage our electrical grids.
But do we know how powerful solar events can be? History may hold the answer.
In September of 1859, a solar flare was so massive that there were newspaper reports of it across the globe, and many found the strange light it created baffling. Of course, now, there’s no speculation as to what happened then–eyewitness accounts and plenty of written evidence in this pre-internet era paint a clear picture of a massive coronal ejection. This event has been referenced many times as a benchmark–one that, should it happen now, would certainly give us serious pause. Technologically, that is.
It hit quickly. Twelve hours after Carrington’s discovery and a continent away, “We were high up on the Rocky Mountains sleeping in the open air,” wrote a correspondent to the Rocky Mountain News. “A little after midnight we were awakened by the auroral light, so bright that one could easily read common print.” As the sky brightened further, some of the party began making breakfast on the mistaken assumption that dawn had arrived.
Across the United States and Europe, telegraph operators struggled to keep service going as the electromagnetic gusts enveloped the globe. In 1859, the US telegraph system was about 20 years old, and Cyrus Field had just built his transatlantic cable from Newfoundland to Ireland, which would not succeed in transmitting messages until after the American Civil War.
“Never in my experience of fifteen years in working telegraph lines have I witnessed anything like the extraordinary effect of the Aurora Borealis between Quebec and Farther Point last night,” wrote one telegraph manager to the Rochester Union & Advertiser on August 30:
The line was in most perfect order, and well skilled operators worked incessantly from 8 o’clock last evening till one this morning to get over in an intelligible form four hundred words of the report per steamer Indian for the Associated Press, and at the latter hour so completely were the wires under the influence of the Aurora Borealis that it was found utterly impossible to communicate between the telegraph stations, and the line had to be closed.
But if the following newspaper transcript of a telegraph operator exchange between Portland and Boston is to be believed, some plucky telegraphers improvised, letting the storm do the work that their disrupted batteries couldn’t:
Boston operator, (to Portland operator) – “Please cut off your battery entirely from the line for fifteen minutes.”
Portland operator: “Will do so. It is now disconnected.”
Boston: “Mine is disconnected, and we are working with the auroral current. How do you receive my writing?”
Portland: “Better than with our batteries on. Current comes and goes gradually.”
Boston: “My current is very strong at times, and we can work better without the batteries, as the Aurora seems to neutralize and augment our batteries alternately, making current too strong at times for our relay magnets.
Suppose we work without batteries while we are affected by this trouble.”
Portland: “Very well. Shall I go ahead with business?”
Boston: “Yes. Go ahead.”
Telegraphers around the US reported similar experiences. “The wire was then worked for about two hours without the usual batteries on the auroral current, working better than with the batteries connected,” said the Washington Daily National Intelligencer. “Who now will dispute the theory that the Aurora Borealis is caused by electricity?” asked the Washington Evening Star.