(From NASA/STScI Digitized Sky Survey/Noel Carboni, used w/o permission.)
"Witch Head Nebula
"As the name implies, this reflection nebula associated with the star Rigel looks suspiciously like a fairytale crone. Formally known as IC 2118 in the constellation Orion, the Witch Head Nebula glows primarily by light reflected from the star. The color of this very blue nebula is caused not only by blue color of its star, but also because the dust grains reflect blue light more efficiently than red. A similar physical process causes Earth's daytime sky to appear blue.
The Witch Head Nebula is either left over from a supernova, or not. Either way, from Earth's angle it looks like the ethically-challenged stepmother in Snow White
or Hansel and Gretel
, sort of. Some of those tales are downright Grimm.
The way light gets scattered by tiny particles is why Earth's sky and the Witch Head Nebula look blue. It's called Rayleigh scattering
, not to be confused with the Raleigh Bicycle Company
, Sir Walter Raleigh
, or Sir Walter Scott
Sorry about that. The Lemming's catching up on sleep, or fighting a cold, or in a puckish
mood. Oddly, "pawkish" isn't in dictionaries, although the Lemming's seen and heard it used. Definitions aboud for gawkish
, and the aforementioned puckish
: but nary a peep about "pawkish."
Somewhere in Earth's sky there must be a nebula that looks like Little Bo Peep
or her sheep, and that's another topic.
(From Hubble Space Telescope, NASA, used w/o permission.)
"Hubble Celebrates Its Seventeenth Birthday with the Birth of a Star
"...one of the largest panoramic images ever taken with Hubble's cameras. It is a 50-light-year-wide view of the central region of the Carina Nebula where a maelstrom of star birth - and death - is taking place....
"...The immense nebula contains at least a dozen brilliant stars that are roughly estimated to be at least 50 to 100 times the mass of our Sun. The most unique and opulent inhabitant is the star Eta Carinae, at far left. Eta Carinae is in the final stages of its brief and eruptive lifespan, as evidenced by two billowing lobes of gas and dust that presage its upcoming explosion as a titanic supernova.
"The fireworks in the Carina region started three million years ago when the nebula's first generation of newborn stars condensed and ignited in the middle of a huge cloud of cold molecular hydrogen. Radiation from these stars carved out an expanding bubble of hot gas. The island-like clumps of dark clouds scattered across the nebula are nodules of dust and gas that are resisting being eaten away by photoionization....
NASA (March 24, 2007)
Like most other things in the sky, the Carina Nebula
has quite a few names and catalog numbers. Depending on who's writing, it's Caldwell 92; or the Eta Carinae Nebula, Grand Nebula, Great Nebula in Carina; or NGC 3372.
A nebula by any other name wouldn't smell as sweet, and the Lemming is not going to go into a Shakespearean frenzy.
Points of interest in the Carina Nebula include the Homunculus Nebula
. There we go with a Halloween theme again. Sort of.
The word homunculus
first showed up in 16th century alchemical records. These drastically undersized human-like critters are sort of related to the mandrake plant, except they don't really exist. That's the Lemming's story, and he's sticking to it.
is another scenic spot in the Carina Nebula, and not to be confused with an amusement park in Jamaica
, or a ski resort in Pennsylvania
. The latter are both on Earth, which may be obvious. Then again, maybe not.