For those new to sun watching, here is some basic information. SOHO stands for Solar and Heliospheric Observatory. It is a satellite that orbits earth and focuses on the sun. It is 0.01 AU (930,000 miles) from the Earth and 0.99 AU from the sun. AU stands for "astronomical unit" and one AU is the average distance between the Earth and the Sun. This distance varies throughout the year. For instance, in the northern hemisphere winter, the Earth is approximately 91 million miles from the Sun (closest approach in the sun's orbit). During the northern hemisphere summer, it is 94.5 million miles from the sun (furthest approach in the sun's orbit). Thus, the average distance from the sun is usually stated as approximately 93 million miles. If you want to know more, see http://en.wikipedia.org/wiki/SOHO_spacecraft.
Here is a master link to Magnetosphere images and charts: http://images.search.yahoo.com/search/images?_adv_prop=image&fr=yfp-t-701&va=magnetosphere. Here is a link to a real-time simulator: http://www2.nict.go.jp/y/y223/simulation/realtime/index.html. This first image below, on the left, shows Earth's magnetic fields are twisted and pressure. Normally, the blue lines (north) go up and the red lines (south) go down. The image on the right with the red and yellow colors indicate the pressure is increasing. It boils down to Earth being slammed by a geomagnetic storm which could be from a solar storm or, possibly, a planet x, brown dwarf star object.
Don't know about the bottom two images. Now, on to the cameras...
LASCO stands for Large Angle and Spectrometric Coronagraph. These are cameras, designated C1, C2 and C3. We tend to focus on C2 (orange) and C3 (blue). C2 is a closer "shot" of the sun and C3 is a wider angle shot. Pictures are automatically taken several times an hour throughout the day and night, 24/7. The circle in the center of the picture is called an occulter and is simply there to block the sunlight otherwise objects passing the sun would be obscured by the intense light. Each picture is dated and timed at the bottom. You can read more about these cameras at http://en.wikipedia.org/wiki/LASCO_Large_Angle_and_Spectrometric_Co.... Here's a C3 image of Venus. Planets have those thin lines on each side of the orb. There are solar flares, those lines of light emanating from the sun. The streak around 08:00, near the arm of the occulter, is a comet. That's how cameras image fast moving objects, they look like streaks...
Here's the same image taken by the C2 camera a few minutes earlier. Notice it is a closer shot than C3...
Here's a link to go see for yourself... http://sohowww.nascom.nasa.gov/data/realtime-images.html. Search and Download Data (in the left bar) is the link to use to be able to select cameras, sizes, times, etc.
STEREO is a different NASA camera and stands for Solar Terrestrial Relations Observatory. These are two nearly identical spacecraft launched into slightly different orbits that cause them to respectively pull further ahead of and fall gradually behind the earth. This enables stereoscopic imaging of the Sun and solar phenomena, such as coronal mass ejections. Stereo A (ahead of the Earth) is moving faster than Stereo B (behind the Earth) and is also closer to the sun. See http://stereo.gsfc.nasa.gov/where.shtml for a graph that shows you where A and B are on the current date. It also shows any planets that might be in view at the time. (This is where I determined the planet is Venus in the C3 image. Since C2 is a closer shot, Venus isn't showing up since it is outside the range.) For more information see http://en.wikipedia.org/wiki/STEREO.
Since PX or a Brown Dwarf Star is coming in on the right side (looking at the sun from Earth), we look at STEREO Ahead Cor2 (orange rust color) mostly. Here's how to check for yourself: http://stereo-ssc.nascom.nasa.gov/cgi-bin/images. And here are some movies that show the orbits: http://stereo.gsfc.nasa.gov/orbit.shtml. And here are the Fields of View (FOV) for the different STEREO cameras: http://stereo.gsfc.nasa.gov/classroom/secchi_fov.shtml. And here is the STEREO planet finder: http://stereo.gsfc.nasa.gov/beacon/planets/, another useful tool to identify planets in the field of view.
Image credit (Stereo above and below): NASA http://www.scribd.com/doc/49006070/Solar-Terrestrial-Relations-Observatory-Stereo-Press-Kit
Understand that A and B are constantly moving so look at the next image, which shows A and B's positions over time and apply the same field of view (FOV) (the shade area from A or B to the sun) to the current year:
Here is a more detailed view of STEREO A and B's approximate orbital locations by year:
Credit: NASA @ http://stereo.gsfc.nasa.gov/360blog/
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