NASA captured a marvelous image of Kappa Cassiopeiae, with the help of their Spitzer Space Telescope, a super speedy red-hot supergiant star.
Kappa Cassiopeiae, also known as HD 2905 to astronomers, is a huge, supergiant star. It also is a fast one, moving at about 2.5 million miles per hour relative to its neighbors. When a star that big gets moving that fast, the red, glowing arcs known as “blow shocks” can appear. The streaking phenomenon, a very rare effect, usually only occurs in front of the largest, fastest moving stars.
Bow shocks form where the magnetic fields and wind of particles flowing off a star collide with the diffuse, and usually invisible, gas and dust that fill the space between the stars per the State Column. Beyond being beautiful, the bow shocks are informative for scientists, giving them information as to the conditions immediately surrounding the star and the space close by.
While our Sun has bow shocks of its own, it moves very slowly in that they are not visible at any wavelength. Kappa Cassiopeiae, on the contrary, moves such that Spitzer’s infrared detectors could observe its bow shock, which in this instance stretches about four light years ahead of the star. It is quite the distance, indicating that Kappa Cassiopeiae is having a large impact on its surroundings.
The Kappa Cassiopeae bow shock shows up as a bright vivid red color The faint green features in the image result from carbon molecules, known as polycyclic aromatic hydrocarbons, in dust clouds along the line of sight that are illuminated by starlight. While Kappa Cassiopeiae is visible to the human eye, observing its bow shock requires infrared equipment, such as that of NASA.
Delicate red filaments run through this infrared nebula. Some astronomers have said these filaments may be tracing out features of the magnetic field that runs throughout the galaxy.