Counting magnetic maelstroms—unraveling the Sun’s mysteries through long-term monitoring of sunspots.
What We Do
The Sun is the nearest star to Earth. As our stellar neighbor, it’s the first that comes to mind—and the standard by which astronomers measure all others. Because of its proximity, we are able to view the solar surface in exquisite detail.
The Sun can change on a timescale of days, but goes through longer periods of activity and inactivity known as the solar cycle. We quantify this activity by looking for dark appearing patches on the surface called sunspots. By “counting” these sunspots we measure the Sun’s activity over time. Your data, aggregated with that of other observers, is reported every month in our Solar Bulletin.
If this seems old-fashioned, that’s because it is—and for good reason! People have been observing the Sun in this way for well over a hundred years, and by continuing this tradition we can directly compare current data with that recorded in the distant past.
How We Do It
There is an art and a science underpinning solar observing to which we have dedicated an entire manual. However, in its simplest form, solar observing is looking at the Sun safely through a proper solar filter attached to a telescope or similar device, or safely projecting its image through your telescope onto a small screen. This allows you to observe groups of sunspots as often as you have clear skies. You then upload the observations to the AAVSO solar database.
Is It Right for Me?
Level: Easy. Solar observing requires some time to get the hang of it, however the bar for entry is fairly low.
Equipment: A small telescope (40- to 80-mm aperture) and a solar filter or projection set-up is all you would need to begin.
Observing Requirements: The Sun is easily observable during the day, weather permitting. Observations will typically take less than half an hour to complete.
Additional Considerations: No reduction tools or computer resources are necessary outside SunEntry, a Java program required for data submission to the special Solar database.