Teapot of Sagittarius: Galaxy’s center


From the Northern Hemisphere, look southward in July and August to find the Teapot in Sagittarius. Notice 2 points: galactic center and winter solstice. From the Southern Hemisphere, turn this chart upside down.

From the Northern Hemisphere, look southward in July and August to find the Teapot in Sagittarius. From the Southern Hemisphere, look generally northward, and high in the sky, and turn this chart upside down.

Modern stargazers have a hard time seeing a Centaur with a bow and arrow in the constellation Sagittarius. But The Teapot – in the western half of Sagittarius – is easy to make out. The Teapot is an asterism, not a constellation, but a recognizable pattern of stars. Two noteworthy points in our sky lie in this direction: first, the center of our Milky Way galaxy and, second, the point at which the sun shines on the December solstice, around December 21 each year.

The Teapot is best viewed during the evening hours from about July to September.

On dark, moonless nights, look for the “steam” billowing out of the Teapot’s spout. It’s the edgewise view into our own galaxy, the combined glow of millions of stars running astride the galactic equator (see sky chart above). You’ll notice that the Milky Way band appears to broaden and brighten in the direction of the Teapot. It’s here that the center of our galaxy lies.

From a dark country sky, scan this river of stars with binoculars. This region of the sky is chock-full of star fields, star clusters, galactic nebulae and dust.

Because the sun passes in front of Sagittarius from about December 18 to January 20, the Teapot isn’t visible then. However, about a half year later – on July 1 – the Teapot climbs to its highest point for the night around midnight (1 a.m. Daylight Time), when it appears due south as seen from the Northern Hemisphere or due north as seen from the Southern Hemisphere.

As seen from our mid-northern latitudes, the Teapot rises in the southeast about 3 hours before its climbs to its highest point, then sets in the southwest about 3 hours afterwards.

The Teapot returns to the same place in the sky about 4 minutes earlier with each passing day, or 2 hours earlier with each passing month. On August 1, the Teapot climbs to its highest point around 10 p.m. (11 p.m. Daylight Time). On September 1, it climbs highest around 8 p.m. (9 p.m. Daylight Time). On October 1, it’s highest around 6 p.m. (7 p.m. Daylight Time).

From the Northern Hemisphere, look southward in July and August evenings to see these stars. From the Southern Hemisphere, look generally northward, higher in the sky and turn this chart upside down. Chart via AstroBob.

From the Northern Hemisphere, look southward in July and August evenings to see these stars. From the Southern Hemisphere, look generally northward, higher in the sky and turn this chart upside down. Chart via AstroBob.

Bottom line: The Teapot asterism in the constellation Sagittarius is easy to spot in a dark sky. When you look in the direction, you’re looking toward the center of our Milky Way galaxy.



from EarthSky http://ift.tt/1EQMdQ2
From the Northern Hemisphere, look southward in July and August to find the Teapot in Sagittarius. Notice 2 points: galactic center and winter solstice. From the Southern Hemisphere, turn this chart upside down.

From the Northern Hemisphere, look southward in July and August to find the Teapot in Sagittarius. From the Southern Hemisphere, look generally northward, and high in the sky, and turn this chart upside down.

Modern stargazers have a hard time seeing a Centaur with a bow and arrow in the constellation Sagittarius. But The Teapot – in the western half of Sagittarius – is easy to make out. The Teapot is an asterism, not a constellation, but a recognizable pattern of stars. Two noteworthy points in our sky lie in this direction: first, the center of our Milky Way galaxy and, second, the point at which the sun shines on the December solstice, around December 21 each year.

The Teapot is best viewed during the evening hours from about July to September.

On dark, moonless nights, look for the “steam” billowing out of the Teapot’s spout. It’s the edgewise view into our own galaxy, the combined glow of millions of stars running astride the galactic equator (see sky chart above). You’ll notice that the Milky Way band appears to broaden and brighten in the direction of the Teapot. It’s here that the center of our galaxy lies.

From a dark country sky, scan this river of stars with binoculars. This region of the sky is chock-full of star fields, star clusters, galactic nebulae and dust.

Because the sun passes in front of Sagittarius from about December 18 to January 20, the Teapot isn’t visible then. However, about a half year later – on July 1 – the Teapot climbs to its highest point for the night around midnight (1 a.m. Daylight Time), when it appears due south as seen from the Northern Hemisphere or due north as seen from the Southern Hemisphere.

As seen from our mid-northern latitudes, the Teapot rises in the southeast about 3 hours before its climbs to its highest point, then sets in the southwest about 3 hours afterwards.

The Teapot returns to the same place in the sky about 4 minutes earlier with each passing day, or 2 hours earlier with each passing month. On August 1, the Teapot climbs to its highest point around 10 p.m. (11 p.m. Daylight Time). On September 1, it climbs highest around 8 p.m. (9 p.m. Daylight Time). On October 1, it’s highest around 6 p.m. (7 p.m. Daylight Time).

From the Northern Hemisphere, look southward in July and August evenings to see these stars. From the Southern Hemisphere, look generally northward, higher in the sky and turn this chart upside down. Chart via AstroBob.

From the Northern Hemisphere, look southward in July and August evenings to see these stars. From the Southern Hemisphere, look generally northward, higher in the sky and turn this chart upside down. Chart via AstroBob.

Bottom line: The Teapot asterism in the constellation Sagittarius is easy to spot in a dark sky. When you look in the direction, you’re looking toward the center of our Milky Way galaxy.



from EarthSky http://ift.tt/1EQMdQ2

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