Messier 94 (M94)

Common Name: Cat's Eye Galaxy

Also Known as: NGC 4736

Object Type: Spiral Galaxy

Constellation: Canes Venatici

Distance from Earth: 16 million light years

Apparent Magnitude: 8.99

Coordinates: RA 12H 50M 53.1S DEC 41 deg 07 min 14 sec

Actual Size: Main disk 50,000 light years in diameter, fainter outer ring extends another 30,000 light years.

Apparent Dimensions: 11.2 arc-minutes x 9.1 arc-minutes

Discovered by: M94 was discovered by Charles Messier’s colleague Pierre Méchain on March 2, 1781.
Méchain reported the discovery to Messier, who found the object, determined its position, and added it to his catalogue of comet-like objects on March 24, 1781.
Messier noted:"Nebula without star, above the Heart of Charles [Cor Caroli, Alpha Canum Venaticorum], on the parallel of the star no. 8, of sixth magnitude of the Hunting Dogs [Canes Venatici]", according to Flamsteed: In the center it is brilliant & the nebulosity [is] a bit diffuse.
It resembles the nebula which is below Lepus, No. 79 [Messier 79]; but this one is more beautiful & brighter; Méchain has discovered this one on March 22, 1781.

Description: M94 is estimated to contain 40 billion stars.
It is moving away from us at 308 km/s. Its main disk is about 50,000 light years in diameter, but the galaxy has a considerably fainter outer ring that extends for at least another 30,000 light years.
M94 is classified as a LINEAR galaxy, meaning a galaxy with a low ionization nuclear emission region.
Some sources classify M94 as a barred spiral, but the galaxy’s “bar” structure appears more oval-shaped.
This means that the nucleus of M94 contains ionized gas, but that the gas is only weakly ionized.
M94 has 2 ring structures. The inner ring has a diameter of 70 arc-seconds and the outer 600 arc-seconds. The inner ring is a site of intense star forming activity and is believed to have formed in a starburst less than 10 million years ago.
The outer ring of M94 is not a closed stellar ring, as previously believed, but a complex spiral arm structure seen in mid-infrared and ultraviolet wavelengths.
In other words, what appears to us as a ring is in fact a structure of two spiral arms that looks like an unbroken ring when seen from Earth.
Observations in 2009 revealed that the outer ring is active and produces about 10 percent of new stars in the galaxy. It also contains about 23 percent of the total stellar mass of M94.
Star forming activity in the outer ring is about two times greater than that in the inner ring.
Messier 94 is the central galaxy in the M94 Group, also known as the Canes Venatici I Cloud (CVn I Cloud), a group that contains 16 to 24 galaxies. Even though there are many galaxies that may be associated with M94, only a few appear to be members of the group. These include the Black Eye Galaxy (M64) and a number of fainter members. M94 is the brightest member of the group, but does not appear to be gravitationally bound to any of the galaxies in the vicinity.

Click Below Image(s) for Full Size:

M94 can be spotted with binoculars under good conditions. But only appears as a small, dim patch of light.
Small telescopes show M94 as a fuzzy patch with brighter center while a 6 or 8-inch scope reveals a bright condensed nucleus surrounded by a nebulosity that hints of spiral structure.
Large scopes reveal a bright ring around the galaxy’s nucleus and details of the structure.

The best time to observe M94 is during the spring months.

Platesolve

M94 Spiral Galaxy

Imaging Details
Click to Return to Home Page