Rosette Nebula Mosaic in Narrowband Light

The huge Rosette Nebula (NGC2244) is located in the constellation Monoceros, and measures about 90 to 100 light years across (540 trillion to 600 trillion miles). It is estimated to contain hydrogen gas about 10,000 times the mass of our sun, and lies about 5,000 light years away (30 quadrillion miles). In the center of the nebula, young stars are forming from the gas cloud. Intense radiation from these stars excites the gas, causing it to glow brightly.

The Rosette is too large to fit completely on my camera's chip, so I exposed half of it at a time and joined the frames together. The five images below represent 26½ hours total exposure collected over 13 nights in January, February, and March 2008 at various camera temperatures and exposure times.

The images were exposed through filters having extremely narrow bandwidths to capture only the light emitted by certain gasses when excited by stellar radiation. This table lists the exposure for each narrowband channel. For variety, the Rosette is shown using different color palettes to represent three gases present in the nebula. Scroll down to see them all.

(Hubble palette)   Red: Sulfur-II     Green: Hydrogen-alpha     Blue: Oxygen-III

This image uses the same color palette as the Hubble Space telescope. Ionized sulfur is red, hydrogen is green, and oxygen is blue. Click on the image for a larger version.

Along the Rosette's northern arc (top), two cloud tendrils spiral together in a "Y" shape. You can see a closer view of this feature here. Other dark clouds and tendrils can be found in the nebula's western region (right), and here is a closer view of that area. The southeast region (lower-left) contains several pillars of dense gas which is condensing to form new stars. You can see details here.

Rosette Nebula, Southeastern Region

In the southeast quadrant of the Rosette can be seen several pillars known as "elephant trunks" rising from the surrounding molecular hydrogen gas and dust. The pillars are so dense that gravity contracts the gas to form stars. At the end of the pillars, radiation from the young stars boils away the lower-density material, revealing the stars' gaseous "cocoons." Ultimately the cocoons themselves will boil away, exposing the stars themselves.

This image comprises a total of three hours exposure.

Rosette Nebula, Northwest Region

Along the Rosette's northern arc, two cloud tendrils spiral together to make a distinctive "Y" shape. Several small star-forming pillars are found along these clouds, at the bottom of the spiral, and in the dark clouds toward the right (west). Click here for the mosaic including a general view of the northern and western regions.

Rosette Nebula, Western Region

This is the western area of the Rosette; north is roughly toward the right. Star-forming pillars are rising from the dark clouds; the three "heads" at the far right are the same ones in the photo above. Click here or here for wider views of this area.