Observed structure of the Milky Way's spiral arms

The Orion Arm or Local Arm (labeled "0") is a minor, spiral arm of the Milky Way galaxy. The Earth's solar system may be found close to the inner rim of the Local Arm, in the Local Bubble, 8.0 ± 0.5 kpc from the galactic center. This arm gets its name from its proximity to the stars in the Orion constellation. The Local Arm is located between the Sagittarius Arm (facing the galactic center) and the Perseus Arm (towards the outer, Cygnus Arm). It is unknown whether the Local Arm is a branch of the Perseus or Sagittarius arm. Observed spiral structure of the Milky Way galaxy following Taylor, J.H. & Cordes, J.M. ApJ 411, 674 (1993). ... Observed spiral structure of the Milky Way galaxy following Taylor, J.H. & Cordes, J.M. ApJ 411, 674 (1993). ... A spiral galaxy presents a face-on view of its spiral arms. ... The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Galaxia Kuklos) is the galaxy in which the Earth is found. ... Earth, also known as the Earth, Terra, and (mostly in the 19th century) Tellus, is the third planet outward from the Sun. ... Presentation of the solar system (not to scale). ... The Local Bubble is a cavity in the local interstellar medium (ISM) at least 300 light years across containing a neutral hydrogen density that is approximately one tenth of that of the average ISM in the Milky Way (approximately 0. ... This article is about the unit of length. ... The Galactic Center is the rotational center of the Milky Way galaxy. ... Orion, a constellation often referred to as The Hunter, is a prominent constellation, perhaps the best-known in the sky. ... The Sagittarius Arm or Sagittarius-Carina Arm (labeled -I) is one of two major spiral arms of the Milky Way galaxy, along with the Cygnus Arm. ... The Perseus Arm (labeled +I) is a spiral arm of the Milky Way galaxy with a radius of 10. ... Observed structure of the Milky Ways spiral arms The Cygnus Arm or Outer Arm (labeled +II) is one of four major spiral arms in the Milky Way galaxy, along with the Sagittarius Arm. ...

A number of Messier objects are found in the Local Arm: M6, M7, M23, M25, M27, M29, M34, M35, M39, M40, M41, M42, M43, M44, M45, M46, M47, M48, M50, M57, M67, M73, M76, M78, M93, M97. Table of all 110 Messier objects. ... The Butterfly Cluster (also known as Open Cluster M6, Messier Object 6, Messier 6, M6, or NGC 6405) is an open cluster in the Scorpius constellation. ... The Ptolemy Cluster (also known as Ptolemys Cluster, the Scorpions Tail, Open Cluster M7, Messier Object 7, Messier 7, M7, or NGC 6475) is an open cluster in the Scorpius constellation. ... Open Cluster M23 (also known as Messier Object 23, Messier 23, M23, or NGC 6494) is an open cluster in the Sagittarius constellation. ... Open Cluster M25 (also known as Messier Object 25, Messier 25, M25, or IC 4725) is an open cluster in the Sagittarius constellation. ... Messier Object 27, the Dumbbell Nebula The Dumbbell Nebula (also known as Messier Object 27, M27, or NGC 6853) is a planetary nebula in the Vulpecula constellation, at a distance of about 1250 light years. ... Open Cluster M29 (also known as Messier Object 29, Messier 29, M29, or NGC 6913) is an open cluster in the Cygnus constellation. ... 2MASS image of M34 (taken in infrared band; falsecolor) Open Cluster M34 (also known as Messier Object 34, Messier 34, M34, or NGC 1039) is an open cluster in the Perseus constellation. ... Open Cluster M35 (also known as Messier Object 35, Messier 35, M35, or NGC 2168) is an open cluster in the Gemini constellation. ... Open Cluster M39 (also known as Messier Object 39, Messier 39, M39, or NGC 7092) is an open cluster in the Cygnus constellation. ... Winnecke 4 (also known as Double Star M40, Messier Object 40 or WNC 4) is a double star in the Ursa Major constellation. ... Open Cluster M41 (also known as Messier Object 41, Messier 41, M41, or NGC 2287) is an open cluster in the Canis Major constellation. ... The entire Orion Nebula in visible light Optical images reveal clouds of gas and dust in the Orion Nebula; an infrared image (right) reveals the new stars shining within. ... De Mairans Nebula (also known as M43 and NGC 1982) is an H II region in the Orion constellation. ... The Beehive Cluster (also known as The Beehive, Praesepe, Open Cluster M44, Messier Object 44, Messier 44, M44, or NGC 2632) is an open cluster in the Cancer constellation. ... The Pleiades, dominated by hot blue stars surrounded by reflection nebulosity The Pleiades (pleye-a-deez or plee-a-deez, also known as M45, or the Seven Sisters) is an open cluster in the constellation of Taurus. ... Open Cluster M46 (also known as Messier Object 46, Messier 46, M46, or NGC 2437) is an open cluster in the Puppis constellation. ... Open Cluster M47 (also known as Messier Object 47, Messier 47, M47, or NGC 2422) is an open cluster in the Puppis constellation. ... Open Cluster M48 (also known as Messier Object 48, Messier 48, M48, or NGC 2548) is an open cluster in the Hydra constellation. ... Open Cluster M50 (also known as Messier Object 50, Messier 50, M50, or NGC 2323) is an open cluster in the Monoceros constellation. ... M57, The Ring Nebula Planetary Nebula M57 (also known as the Ring Nebula, NGC 6720 or Messier Object 57) is located in the constellation Lyra. ... Open Cluster M67 (also known as Messier Object 67, Messier 67, M67, or NGC 2682) is an open cluster in the Cancer constellation. ... M73 (also known as NGC 6994) is a group of four stars very close to each other in the constellation of Aquarius. ... The Little Dumbbell Nebula (also known as the Cork Nebula, the Butterfly Nebula, the Barbell Nebula, Planetary Nebula M76, Messier Object 76, Messier 76, M76, NGC 650, or NGC 651) is a planetary nebula in the Perseus constellation. ... The Diffuse Nebula M78 (also known as Messier Object 78, Messier 78, M78, or NGC 2068) is a diffuse nebula in the Orion constellation. ... Open Cluster M93 (also known as Messier Object 93, Messier 93, M93, or NGC 2447) is an open cluster in the Puppis constellation. ... The Owl Nebula (also known as Planetary Nebula M97, Messier Object 97, Messier 97, M97, or NGC 3587) is a planetary nebula in the Ursa Major constellation. ...

See also

• List of Messier objects

Table of images of all 110 Messier objects. ...

External links

• Galactic Structure, Galactic Rotation Curve and Measurements on the M31 galaxy
• http://skyandtelescope.com/mm_images/6829.jpg