THE BRILLIANT WINGS OF A COSMIC BUTTERFLY.
Photo By: Judy Schmidt via the Hubble Legacy Archive. CLICK the photo for full size and see below for all links.
This is probably the single most beautiful shot of Minkowski’s Butterfly I have ever seen. Cataloged as M2-9 it is what’s known as a planetary nebula, bipolar planetary nebula to be precise. Before we delve into the details as to what we’re seeing, let’s hear from Judy Schmidt as to how this photo came about from raw, unexploited Hubble Space Telescope data. The following is from her actual page on this photo which I have provided the link for below. Also, this isn’t the first photo of Judy’s I have highlighted; remember the blue spiral galaxy M77, that I posted in August; that’s her processing work as well.
“While stalking about the archive for my next planetary nebula victim, I was surprised to find a picture of M2-9 at such high resolution compared with the other images I’ve seen of it. The image was only available in black and white and was acquired using STIS which is usually used for spectroscopy but it obviously has another use, since this isn’t a spectrum.
Anyway, then I took some lower resolution WFPC2 data from one year earlier (the date is important because this nebula has a kind of lighthouse thing going on with the two beams of light which appear blue in my image…yes, they rotate, something like a lighthouse) and used it to generate some colors for the nebula. This resulted in SII for the red channel, STIS / MIRVIS data in the green channel, and OIII in the blue.
Note that the stars surrounding it have only one channel of data and I colored them a yellowish hue because I thought it looked better than grayscale.
Green: STIS / MIRVIS data
North is NOT up.”
Now let’s discuss the object itself. M2-9 was discovered in 1947 by German-American astronomer Rudolph Minkowski. It’s located about 2100 light years distant in the constellation Ophiuchus and what strikes you instantly when you see this object are the two, very distinct lobes of material firing off in two separate directions. I think we’re all pretty comfortable as to what planetary nebula are correct? To summarize it’s when a star similar to our own Sun nears the end of its life and swells to a red giant, puffs out or releases its outer layers into the cosmos and the then exposed inner layer of the star showers the expelled material with ultraviolet radiation rendering it glow. At its center remains a white dwarf star.
So what if we don’t want a standard planetary nebula; we want a bipolar planetary nebula! Ok, well let’s start by saying the process of forming planetary nebulae is not 100 percent certain, so bipolar planetary nebulae are even less well known; especially now with the news coming out two weeks ago of the discovery of the bipolar planetary nebulae alignment in our galaxy. However, we take our best models and observations and move on. In this particular case it’s believed that at the heart of this structure resides a binary star system (2-star system) where one star orbits another star (Like most stars in the galaxy). To start, the stars have still gone through the above processes to get to the planetary state; but because of the double star system that material takes a less than spherical shape. The smaller companion star in orbit around the dying star chokes off access to expelled material in the lateral direction, causing it to then fire off in two directly opposite directions at a staggering 200 miles per second.
The central star in M2-9 is known to be one of a very close pair which orbit one another at perilously close distances. It is even possible that one star is being engulfed by the other. Astronomers suspect the gravity of one star pulls weakly bound gas from the surface of the other and flings it into a thin, dense disk which surrounds both stars and extends well into space.
The disk can actually be seen in shorter exposure images obtained with the Hubble telescope. It measures approximately 10 times the diameter of Pluto’s orbit. Models of the type that are used to design jet engines (“hydrodynamics”) show that such a disk can successfully account for the jet-exhaust-like appearance of M2-9. The high-speed wind from one of the stars rams into the surrounding disk, which serves as a nozzle. The wind is deflected in a perpendicular direction and forms the pair of jets that we see in the nebula’s image. This is much the same process that takes place in a jet engine: The burning and expanding gases are deflected by the engine walls through a nozzle to form long, collimated jets of hot air at high speeds.
NAME: Minkowski 2-9, M2-9, Minkowski’s Butterfly, Twin Jet Nebula.
WHAT IS IT?: Bipolar Planetary Nebula and the death of a binary star system.
HOW FAR AWAY IS IT?: Approximately 2100 light years distant.
HOW BIG IS IT?: Approximately 115” X 18” arcseconds on the night sky and 1.4 light years long.
APPARENT MAGNITUDE?: A very dim 14.5 or +14.5.
WHERE IS IT? (General): Constellation Ophiuchus the “Serpent Bearer”.
WHERE IS IT? (Exact RA/DEC J2000): RA 17h 05m 37.95s / DEC −10° 08′ 34.58″.
Hubble Legacy Archive: http://hla.stsci.edu/
Judy’s main page for this photo: http://geckzilla.com/art/v/246
Judy’s Flickr page for this photo: http://www.flickr.com/photos/geckzilla/9732993912/
NASA APOD page for this photo: http://apod.nasa.gov/apod/ap130915.html
Capella Observatory data on this object: http://www.capella-observatory.com/ImageHTMLs/PNs/M2-9.htm
NIGHT SKY ATLAS page for this object: http://www.nightskyatlas.com/viewer.jsp?rightAscension=17.0933&declination=-10.145&viewAngle=20.0
SIMBAD data page for this object: http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Twin+Jet+Nebula
ESA Hubble Space Telescope page for this object: http://www.spacetelescope.org/images/opo9738a/
NASA Hubblesite News Center page for this object: http://hubblesite.org/newscenter/archive/releases/1997/38