NASA is just chuck full of good news this week. In addition to the New Horizons flyby and views of Pluto, the return of a solar observer is back in view. So if you didn’t see enough of the sun today, check this out! The purple image of the sun is from the Extreme Ultraviolet Imager onboard NASA’s Solar TErrestrial RElations Observatory Ahead (STEREO-A) spacecraft. The sun collects data in wavelengths that are not visible to the human eye. This was 171 angstroms and colored blue or violet for the ultraviolet range in the spectrum.
Dark Side Of The Sun?
Pink Floyd sang of the Dark Side Of The Moon, but there is technically a dark side of the sun as well. At least in relation to Earth and the scientists in our backyard tracking from the Goddard Space Flight Center in Greenbelt, MD. It’s not the science fictional planet X, but one or both of a pair of satellites that view the sun get positioned on the opposite side from Earth preventing data transmission due to Conjunction with the sun. It happened last year as well. In 2015, from March 24 to July 8 there was no communication even though the satellites were collecting data in an energy saving mode. It won’t be until 2016 that normal operations will completely resume.
The line of sight was blocked by the sun for only a few days, but the sun interfered with the communication for a wider window. This is due to the proximity to the edge of the sun from our view, and the closeness to the sun. See video of the STEREO Mission below:
On a side note, Earth’s orbit is not circular, but elliptical. The planet is closest to the sun in mid winter on January 4, and furthest in summer. We just passed that aphelion on July 6th, which brought our planet 3 million miles farther from the sun than winter’s perihelion. This is not what impacted the STEREO communication though. Just a fun fact you can share at your next party 😉