Dust Sculptures in the Rosette Nebula (APOD 2009 Dec. 2)

[neufer]

http://apod.nasa.gov/apod/ap080214.html
http://apod.nasa.gov/apod/ap091202.html

<<The best time of day to dust roses is late evening when the air is still and there is dew on the rose bush leaves. This will help the dust settle on the roses and the dew help hold the dust in place. Dust the roses from the under side of the bush. Most pests live and hide under the rose’s leaves, and dusting from the top of the rose won’t get the dust where the pests are hiding. The goal is to create a cloud of dust that will settle all over the roses and into every little nook and cranny that might be harboring pests.>>

[orin stepanek]

Here's an older APOD of the Rosette Nebula. http://antwrp.gsfc.nasa.gov/apod/ap051223.html

Orin

[Charris]

In many of the APOD pictures, there will be a large gas cloud in the background with numerous foreground stars.
The description for today says the cloud is 2500 light years away and 50 light years across.

This does not seem right although it probably is correct. Are not the distances between stars 5-10 light years. And, if so
the stars in todays pictures would stretch far more than 50 light years across.
So I am confused.

CH

[bystander]

In many of the APOD pictures, there will be a large gas cloud in the background with numerous foreground stars.
The description for today says the cloud is 2500 light years away and 50 light years across.

This does not seem right although it probably is correct. Are not the distances between stars 5-10 light years. And, if so
the stars in todays pictures would stretch far more than 50 light years across.
So I am confused.

CH

Most of the stars you see in this apod are in the foreground, between us and the nebula.

[apodman]

Two foreground stars that look close together can be anywhere along your line of sight as much as 2500 ly (actually the APOD description says 4500 ly) apart.

[neufer]

<<An H II region is a cloud of glowing low density gas and plasma, sometimes several hundred light-years across, in which star formation is taking place. Young, hot, blue stars which have formed from the gas emit copious amounts of ultraviolet light, ionizing and heating the gas surrounding them. H II regions are often associated with giant molecular clouds from which they form together with stars. The first H II known region is Orion Nebula discovered in 1610 by Nicolas-Claude Fabri de Peiresc.

H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II by astronomers (H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). They have extremely diverse morphologies, because the distribution of the stars and gas inside them is inhomogeneous. They often appear clumpy and filamentary, sometimes showing bizarre shapes like the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster such as the Pleiades.

H II regions can be seen out to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Spiral and irregular galaxies contain a lot of H II regions, while elliptical galaxies are almost devoid of them. In the spiral galaxies, including the Milky Way, H II regions are concentrated in the spiral arms, while in the irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.>>

http://antwrp.gsfc.nasa.gov/apod/ap020123.html
http://antwrp.gsfc.nasa.gov/apod/ap090414.html
http://antwrp.gsfc.nasa.gov/apod/ap030310.html
http://antwrp.gsfc.nasa.gov/apod/ap060518.html
http://antwrp.gsfc.nasa.gov/apod/ap020822.html
http://antwrp.gsfc.nasa.gov/apod/ap050930.html
http://antwrp.gsfc.nasa.gov/apod/ap011218.html

[jrgriffinmd]

The dark dust lanes of this nebula look like a strand of DNA that is wound at the bottom of the photo and is unwinding at the top.

[neufer]

The dark dust lanes of this nebula look like a strand of DNA that is wound at the bottom of the photo and is unwinding at the top.

The nebula even has free ribosomes with disulfide bonds.

<<Free ribosomes can move about anywhere in the cytosol, but are excluded from the cell nucleus and other organelles. Proteins that are formed from free ribosomes are released into the cytosol and used within the cell. Since the cytosol contains high concentrations of glutathione and is therefore a reducing environment, proteins containing disulfide bonds, which are formed from oxidized cysteine residues, cannot be produced in this compartment.>>