An infrared image of the Tadpole nebula, a star-forming hub in the Auriga constellation about 12,000 light-years from Earth accidentally captured an asteroid in our solar system passing by. The asteroid, called 1719 Jens discovered in 1950, orbits in the main asteroid belt between Mars and Jupiter.
The space rock, which has a diameter of 19 kilometers (12 miles), left tracks across the image, seen as a line of yellow-green dots in the boxes near center. A second asteroid, called 1992 UZ5, was also observed cruising by, as highlighted in the boxes near the upper left (the larger boxes are blown-up versions of the smaller ones).
WISE also happened to showcase two satellites orbiting above WISE (highlighted in the ovals) streak through the image, appearing as faint green trails. The apparent motion of asteroids is slower than satellites because asteroids are much more distant, and thus appear as dots that move from one WISE frame to the next, rather than streaks in a single frame.
This Tadpole region is a violent nursery of stars as young as only a million years old -- infants in stellar terms -- and masses over 10 times that of our sun. It is called the Tadpole nebula because the masses of hot, young stars are blasting out ultraviolet radiation that has etched the gas into two tadpole-shaped pillars, called Sim 129 and Sim 130.
These "tadpoles" (image below) appear as the yellow squiggles near the center of the frame. The knotted regions at their heads are likely to contain new young stars. WISE's infrared vision is helping to ferret out hidden stars such as these.
Source: The Daily Galaxy - NASA/WISE