Starship Asterisk*

Trifid, Lagoon, and Mars

Explanation: Bright nebulae and star clusters along this 5 degree wide field of view are popular stops on telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. Cataloged by 18th century French astronomer Charles Messier, M20, the colorful Trifid Nebula, and M8, the expansive Lagoon Nebula, are at upper left and center. Both are well-known star forming regions about 5,000 light-years distant. Just passing through the same field of view on September 29, the yellowish star lined up with M8 and M20 at the lower right is actually Mars, close to 8.8 light-minutes from Earth on that date. That distance is nearly equivalent to 1 astronomical unit or the distance from Earth to Sun. Mars is overexposed in the image, with visible diffraction spikes created by the telescope mirror supports. Of course, Mars has long been known to wander through planet Earth's night skies.

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Okay - M-20, M-8 and M-ars.

Nice picture!

Ann

Why Mas is close to 8.8 light-minutes from Earth? Mars's distance to Sun is more than Earth's distance to Sun, and distance from Earth to Sun is 8 light-minutes.

atnastr wrote:Why Mas is close to 8.8 light-minutes from Earth? Mars's distance to Sun is more than Earth's distance to Sun, and distance from Earth to Sun is 8 light-minutes.

Because right now, Earth is roughly between the Sun and Mars, such that we're about the same distance from both.

The Trifid nebula is often displayed with its distinctive red-blue colors. But what is a Trifid? I thought it was a popular episode of Star Trek.
Oh – that was a Tribble.

Trifid was in The Alternate Factor. "Forgettable" it was said. But back to the Trifid - it looks like four lobes to me

Fred the Cat wrote:The Trifid nebula is often displayed with its distinctive red-blue colors. But what is a Trifid? I thought it was a popular episode of Star Trek.
Oh – that was a Tribble.

Trifid was in The Alternate Factor. "Forgettable" it was said. But back to the Trifid - it looks like four lobes to me

The traditional names for most objects were based on visual appearance, not photographs, so unless you are using a large scope, it is difficult to see the fourth dark lane dividing the nebula. I can plainly see four segments through a 20" with a narrow-band filter, but only three are obvious through a 4" refractor.

Visual_Astronomer wrote:

Fred the Cat wrote:The Trifid nebula is often displayed with its distinctive red-blue colors. But what is a Trifid? I thought it was a popular episode of Star Trek.
Oh – that was a Tribble.

Trifid was in The Alternate Factor. "Forgettable" it was said. But back to the Trifid - it looks like four lobes to me

The traditional names for most objects were based on visual appearance, not photographs, so unless you are using a large scope, it is difficult to see the fourth dark lane dividing the nebula. I can plainly see four segments through a 20" with a narrow-band filter, but only three are obvious through a 4" refractor.

As Spock might have said, "That's logical" Thanks!

Awesome shot...

My M20....through my 10" Meade LX 200...with DSI II color camera....
I don't have the Lagoon Neb....yet....

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