With the help of a telescope “Hubble” astronomers have new images of two young planetary nebulae: NGC 6302, also known as the Butterfly nebula, and NGC 7027. Both sites — key sources for understanding the formation processes of planetary nebulae, it is reported in the article in the magazine Galaxies.
On a cosmic scale, planetary nebula live for very long — only a few tens of thousands of years. Despite the name, nothing to do with planets or exoplanets they do not have: this term arose because the first objects of this type found with early telescopes looked like the correct discs that resembled the disks of planets. It was later revealed that planetary nebulae have a complex structure: in fact is a gas shell dropped low stars high-mass (0.8 to 8 solar masses) in the latter stages of evolution.
Today astronomers agree that the nebula is becoming so a variety of shapes (in space there are objects, like spiral, spheres, hourglasses, rectangles), because near the Central star is exerting influence on it companion, also due to the fact that the substance discharged by the star, passing from the asymptotic branch of giants to white dwarfs, interacting with material ejected in stellar wind. However, more precise details of the processes are unknown to scientists, so they continue to explore planetary nebulae using telescopes.
Joel Castner (Joel H. Kastner) at Rochester Institute of technology along with colleagues studied the nebulae NGC 6302 and NGC 7027 with the Hubble. The telescope already took pictures of objects in the past, now, however, researchers used camera-Wide Field Camera 3: it is possible to obtain images in several ranges of electromagnetic waves, from the near ultraviolet to near infrared. The new images clearly show how both the nebula dispersed over very short periods of time, allowing astronomers to see changes even on the scale of decades.
Both nebulae contain a large amount of dust and gas. NGC 7027 is composed of narrow dust rings that flank the minor axis of the elliptical shell, and a complex set of multiple emissions. Form of the nebula indicates that for several centuries the Central star was quietly dropped a gas shell, creating a spherical symmetric cocoon, but recently there have been some event that led to the emergence of “bursts”.
The Butterfly nebula, or NGC 6302, has a distinct S-shaped pattern, shown in red-orange color. This form is seen only in the near-infrared range when the camera of Hubble detects radiation from ionized iron atoms. The radiation indicates the energy of the collisions, both slow and fast winds, which is most frequently observed in active galactic nuclei and supernova remnants.
Recently the Hubble noted the thirtieth anniversary of working in space. This is the most famous and successful orbital Observatory from working today. Observations made telescope helped astronomers to make many discoveries, about which you can read in our article “have Worked for 52”.