Don’t Panic – NASA’s Tuesday Solar Press Conference

| September 21, 2008

solar-04mar08.jpg

Friday the blog world was examining this curious press release from NASA:

NASA To Discuss Conditions On And Surrounding The Sun

WASHINGTON — NASA will hold a media teleconference Tuesday, Sept. 23, at 12:30 p.m. EDT, to discuss data from the joint NASA and European Space Agency Ulysses mission that reveals the sun’s solar wind is at a 50-year low. The sun’s current state could result in changing conditions in the solar system.

Bloggers took this in ran in several directions at once, ranging from NASA getting ready to declare that the next ice age is upon us, the Sun is about to go out and all manner of speculation in between. Now, courtesy of Watt’s Up With That, a bit of perspective.

The press conference Tuesday is instead to discuss this paper: Weaker solar wind from the polar coronal holes and the whole Sun

Abstract

Observations of solar wind from both large polar coronal holes (PCHs) during Ulysses’ third orbit showed that the fast solar wind was slightly slower, significantly less dense, cooler, and had less mass and momentum flux than during the previous solar minimum (first) orbit. In addition, while much more variable, measurements in the slower, in-ecliptic wind match quantitatively with Ulysses and show essentially identical trends. Thus, these combined observations indicate significant, long-term variations in solar wind output from the entire Sun. The significant, long-term trend to lower dynamic pressures means that the heliosphere has been shrinking and the heliopause must be moving inward toward the Voyager spacecraft. In addition, our observations suggest a significant and global reduction in the mass and energy fed in below the sonic point in the corona. The lower supply of mass and energy may result naturally from a reduction of open magnetic flux during this period.

Received 11 June 2008; accepted 14 August 2008; published 18 September 2008.

Ulysses_spacecraft_525.jpg

What does this mean? The spacecraft Ulysses, which recently ended its mission, gathered a great deal of data about our Sun during its years orbiting pole to pole. Part of what it saw on its last orbit was a marked decrease in solar output. This is consistent with the “quiet sun” period we have been seeing the last several months.

Does this mean we should all run out and buy “Snow Machines”? It does mean that as long as these conditions hold, the Sun is pumping less heat and energy into Earth’s atmosphere. However keep in mind that our world’s oceans are an enormous heat sink, and any changes to input energy will only slowly make a difference in temperature over time.

The net outcome is the Ulysses project was a huge scientific win, and NASA would do well to consider a follow on mission in the same vein. If the trend continues, we have a fantastic opportunity to study our sun during a period of quiet unlike what we have had the opportunity to study in the modern age.

[Update] The awesome solar site solarcycle24.com shows a new “sunspeck” in today’s update. One of the tiny tiny little dots that have been the best that cycle 24 could muster thus far have shown up in the past hours. Sadly it’s too late for me to image it directly from the back porch…

Be Sociable, Share!

Category: Climate Change, Main, Science, Space

About the Author ()

Bruce Henderson is a former Marine who focuses custom data mining and visualization technologies on the economy and other disasters.

Comments are closed.