Hawaiian Astronomical Society

Constellations: Triangulum -- A Triangle

Myth

With a name like this, you expect a good myth? Still, the ancients saw a triangle here, too. Some called it the Nile River delta, others the Island of Sicily (check a map for the shape of the island; it's located just south of the mainland portion of Italy). The Greek letter Delta is a triangle in its capital form; consequently Triangulum was sometimes called "Deltotum."

Maps

Each map can be clicked on to produce a 916x1200 version of it. They sport red labels, which look good on screen, but which disappear when used with red flashlights. Each map, therefore has a second link to a map better suited for printing in a graphics program, and using in the field. While they are quite large, they are all about 50k, and so are easy to view at today's modem speeds. The first map is a wide area view of the constellation, suitable for naked eye browsing. The next views are binocular width, showing stars to mag. 10, deepsky objects to mag. 12.9, and labeling deepsky objects to magnitude 12.

Interactive, wide area map of Triangulum

Click the map for a 916x1200 version of the above. Click here for a map better suited for use in the field.

Detailed View

This a more detailed view of the constellation. The map displays stars to magnitude 10, and deepsky objects to magnitude 12. Click here for a map better suited for use in the field.

Images

The Pinwheel Galaxy

Image thumbnail 38k GIF. M33 (NGC598) is a fairly bright (mag. 6.2) galaxy located in western Triangulum near the Pisces border. On a dark night you can glimpse it with the naked eye. It is easy in binoculars, but low surface brightness (its size is 70'x42') makes it difficult in telescopes under light polluted skies. High contrast optics and a dark sky, however, allow you to see several bright knots in the galaxy (each with its own NGC number). The brightest of these knots is NGC604, found in the north-eastern arm of the galaxy. Under dark skies it has been glimpsed in a 6".

Map Printable Map More M33 info. More NGC604 info.

Image thumbnail 64k JPEG. M33 taken with Celestron 8 and ST-7 camera from Mount Pinos. Mosaic of 4 15 minutes exposures... 2x2 binning. Note how nicely the arms are resolved into individual stars. -- Benoit 170k JPEG. M33 presented in false color (for extended dynamic range). You should view this in 18 or 24 bit color. Image: 30 min ST-7 (9u) on 4" f/5 Genesis. Log scaled, then 3 graduated linear scales combined as RGB layers. Stan Moore

Image thumbnail 102k GIF. NGC 925 is a mag. 10, 10'x5' galaxy located in east-central Triangulum. A significant galaxy in its own right, M33 overshadows it. Dreyer describes it as faint, large, elongated, and with gradual brightening toward the middle. Two mag. 13 stars just to the north, preceding (west) side.

Map Printable Map

If you have any questions about the Hawaiian Astronomical Society
please (link requires javascript).