The rain overnight and this morning has me looking through photos of Sunny days to escape the gray. I’ve noticed that pictures taken in the late afternoon and early morning are best for that. Not only do shadows stand taller at dusk and dawn, but colors are also more vibrant and warm.
Sun and Moon
The sun this afternoon and tonight’s moon, these were both shot with the Canon at medium size so the detail might not be as high as you are used to if you come here often:
Sunset and Moonrise
Tonight’s sunset, followed by tonight’s moonrise, taken with a Canon EOS Rebel XTI, the older 10.1 Megapixel model. The newest version is an awesome 15.1 megapixels. Canon EOS 50D 15.1MP Digital SLR Camera (Body Only) You can see the large size of the photos by clicking on the thumbnails, and you should also understand that even these are not the full resolution size of the 10.1 MP Canon, they are about a sixth to an eigth of the real resolution. To get these shots I’m using a Canon EF 70-300mm f/4-5.6 IS USM Lens for Canon EOS SLR Cameras with the sun shot at 135mm and the moon at 300 mm.
What we’re seeing is a long term trend, a steady decrease in pressure that began sometime in the mid-1990s
The Ulysses satellite Solar Wind Observations Over the Poles (SWOOPS) solar wind sensors are reporting a 20 percent drop in pressure, with only a 3 percent drop in speed. Dave McComas, the principle investigator for the project, states this as the lowest solar wind pressure observed since the early sixties when we began measuring it.
“What we’re seeing is a long term trend, a steady decrease in pressure that began sometime in the mid-1990s,” explains Arik Posner, NASA’s Ulysses Program Scientist in Washington DC.
How unusual is this event?
“It’s hard to say. We’ve only been monitoring solar wind since the early years of the Space Age—from the early 60s to the present,” says Posner. “Over that period of time, it’s unique. How the event stands out over centuries or millennia, however, is anybody’s guess. We don’t have data going back that far.”
What this bodes longer term is unknown, we don’t have a long history of solar wind measurements to judge by. Here’s a link to the positve Ion measurements half of the data if you want to take a look at it yourself, and I’ve also included a McComas jpg visual above, click the thumbnail to enlarge. On Earth we aren’t going to be affected short term, but Space Travel has become slightly more dangerous due to increased Cosmic Ray penetration of the Heliosphere.
“The solar wind isn’t inflating the heliosphere as much as it used to,” says McComas. “That means less shielding against cosmic rays.” Dave McComas
To picture this think of the solar wind pressure emanating from the sun as part of the atmosphere of the sun (no, it really isn’t, but bear with me a moment;) a huge bubble around the solar system called the Heliosphere. Then picture that heliosphere zooming through a dense sea of Cosmic rays. Still can’t picture it? Take a look here.
Anecdotal but truth as I know it: People living near the poles will also be exposed to more cosmic rays, which could lead to some effects. One of the visible effects I’ve observed is higher incidence of gray hair at earlier ages in populations living near the Northern pole. Earth’s magnetic shield is the backstop for the heliosphere in stopping cosmic rays from affecting life on Earth, and the shape of the magnetic field allows entry to more Cosmic rays at the poles.
Another effect could be on Clouds and climate, which the linked story speaks of.
The solar winds are now the lowest they’ve been in fifty years, meaning that the Sun’s effects on our solar system are also at an ebb. The Ulysses solar probe is providing these measurements, and the winds have not only lessened, but are also 13% cooler. Much more at BBC.
“This is a whole Sun phenomenon,” said Dave McComas, Ulysses solar wind instrument principal investigator, from Southwest Research Institute, San Antonio, US.
“The entire Sun is blowing significantly less hard – about 20-25% less hard – than it was during the last solar minimum 10-15 years ago.
“That’s a very significant change. In fact, the solar wind we’re seeing now is blowing the least hard we’ve see it for a prolonged time, since the start of those observations in the 1960s at the start of the space age.”
In addition to being calmer, the wind measured at Ulysses is 13% cooler.
However, judging from Sun activity data collected by non-satellite methods over the past 200 years, the current behaviour is thought to be well within the long-term norm.
Nonetheless, scientists expect the weakened wind to have a wide range of impacts.
Among the notable effects of this will be cooling of our upper atmosphere, and increased penetration through the solar system of external cosmic rays.