Aurora borealis philadelphia 41313

Historical View of the sun spots. For years, from the time of Galileo until now, we have been keeping track of the number of these sunspots and, as the trends show in these two graphs, this cycle is predictable. A: We are just starting to come out of a 4-year trough of Solar Cycle The big question now is what will the upswing into Solar Cycle 25 present?

These are the nights with darkness in them. During the summer months of May, June and July it is just too bright to see them in the far northland. Statistically, the equinox months of September and March are best for aurora activity. Note comet Hale-Bopp in the lower right hand corner. Michael Klensch The Processes that Cause Aurora The light of the aurora is generated by atoms and molecules of the air when they are struck with energetic particles from space.

Figure 6. A large spiral that fills a large portion of the sky in this extreme wide-angle photo from Ester Dome near Fairbanks, Alaska. Poul Jensen Light Emission in Aurora When energetic electrons strike an atom or molecule, they slow down and transfer some of their energy to that atom or molecule.

Figure 7. Intense aurora develops a purple border below the green curtains in this fish eye view of almost the entire sky above Fairbanks, Alaska. Note the Big Dipper near the zenith. Figure 8. High-energy auroral electrons above Fairbanks, Alaska penetrate deep enough to cause the purple lower border of the green curtains. High-energy aurora also produces highly structured and very thin curtains that move fast. Short exposure times are necessary to resolve these structures.

Poul Jensen However, the auroral electrons sometimes have enough energy to give them the punch to penetrate deeper than that into the atmosphere. Figure 9. Figure The structure of the curtain below is lost in the red aurora because the excited atoms can move with the wind before emitting light.

Michael Klensch In addition to looking at the color balance and brightness, we can measure the wavelength of individual emission lines in the aurora with very high accuracy. The wind vectors at miles km altitude drawn over a composite all-sky image of the green and red oxygen emission. Through its interaction with the atmosphere, the aurora modifies the wind direction and speed in the upper atmosphere.

Michael Klensch These FPI wind observations only give the component of the wind velocity along the line of sight, the component toward or away from the observing station. Michael Klensch Putting it all Together The observations of the colors of the aurora, either in a broader sense by looking at the overall color balance, or by detailed spectroscopic methods, can teach us much about the physical processes that cause aurora and the effects that aurora has on the upper atmosphere.

This photo is taken shortly after sunset, when the sun illuminates the upper part of the aurora. Ions that are produced by the aurora at these altitudes scatter the blue part of the sunlight, causing the upper edge of the aurora to look blue.

More aurora photos by these photographers can be found at their websites: www. Jensen www. Theusner www. Klensch climate. Curtis www. Conde, M. Anderson, and C. Eather, R. Lummerzheim, D. Modeling and forecasting aurora. Computing in Science and Engineering 9 5 You Might Also Like.

After several months of hiatus, the sun has awoken into a new period of solar activity. The incoming solar weather can actually cause communication disruptions such as GPS positioning errors and interference within our power grid. Of course, a pleasant effect of the incoming solar activity will be a dazzling display of the aurora borealis. This triggers reactions forcing photons of light activated by oxygen and nitrogen molecules in the upper atmosphere.

So there is a lot of buzz about potential SolarStorm heading our way. Yellow line on the map shows the furthest southward potential for the NorthernLights could be observed. Even though the forecast peak of the northern lights is for three hours starting at 10 p.

Follow Us:. Share Tweet Email. Share: Share Tweet Email. If you're in the northern United States on Monday evening, look to the sky! A solar storm is expected to hit Earth, triggering auroras -- or what we know as the northern lights.