Milky Way

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Milky Way : the galaxy of which the sun and the solar system are a part and which contains the myriads of stars that create the light of the Milky Way — Merriam-Webster See also OneLook

Encyclopedia

Milky Way is the galaxy that contains our Solar System. The descriptor “milky” is derived from the galaxy’s appearance from Earth: a band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within.

The Milky Way is a barred spiral galaxy with a diameter between 150,000 and 200,000 light-years (ly). It is estimated to contain 100–400 billion stars. There are probably at least 100 billion planets in the Milky Way. The Solar System is located within the disk, 26,490 (± 100) light-years from the Galactic Center, on the inner edge of the Orion Arm, one of the spiral-shaped concentrations of gas and dust.

The stars in the innermost 10,000 light-years form a bulge and one or more bars that radiate from the bulge. The galactic center is an intense radio source known as Sagittarius A*, likely a supermassive black hole of 4.100 (± 0.034) million solar masses.

The Milky Way has several satellite galaxies and is part of the Local Group of galaxies, which form part of the Virgo Supercluster, which is itself a component of the Laniakea Supercluster. — Wikipedia

Milky Way Galaxy (Encyclopædia Britannica)
Milky Way (COSMOS: The SAO Encyclopedia of Astronomy)

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Adventures

Explore related posts on Cosma …

Milky Way Lost & Found - Have you seen the Milky Way? You may think that you have, but are you sure? Unless you live in an extremely remote area, or you’ve visited one, then you probably haven’t seen our own galaxy, the Milky Way, very well, or at all. Worse yet, you may not even realize that it’s missing. The … Continue reading Milky Way Lost & Found

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Inspiration

Explore Gaia’s all-sky view of our Milky Way Galaxy and neighbouring galaxies in 360 degrees. The map, based on measurements of nearly 1.7 billion stars, shows the total brightness and colour of stars observed by the ESA satellite in each portion of the sky between July 2014 and May 2016. ESA Science & Technology

Note: This is a 360° Video — press and hold to explore it!

ESA Science & Technology (YouTube Channel)
ESA Science & Technology (Official Website)

360° View of Gaia’s Sky (ESA Science & Technology)
The Latest Star Map from the Gaia Spacecraft Plots 1.7 Billion Stars (Lisa Grossman, Science News)

A 360-degree movie immerses viewers into a simulation of the center of our Galaxy. This visualization was enabled by data from Chandra and other telescopes and allows viewers to control their own exploration of this region. — Chandra X-ray Observatory

Note: This is a 360° Video — press and hold to explore it!

Chandra X-ray Observatory (YouTube Channel)
Chandra X-ray Center (Official Website)

This zoom video sequence starts with a broad view of the Milky Way. We then dive into the dusty central region to take a much closer look. There lurks a 4-million solar mass black hole, surrounded by a swarm of stars orbiting rapidly. We first see the stars in motion, thanks to 26 years of data from ESO’s telescopes. We then see an even closer view of one of the stars, known as S2, passing very close to the black hole in May 2018. The final part shows a simulation of the motions of the stars.– European Southern Observatory

European Southern Observatory (YouTube Channel)
European Southern Observatory (Official Website)

Zooming in On the Heart of the Milky Way (European Southern Observatory)
Zoomable Image (European Southern Observatory)

This video shows a continually-looping infrared view of our Milky Way galaxy, as seen by NASA’s Spitzer Space Telescope. The icon in the lower right corner shows how the view changes over time, from our position in the Milky Way. The mosaic comes primarily from the GLIMPSE360 project, which stands for Galactic Legacy Mid-Plane Survey Extraordinaire. It consists of more than 2 million snapshots taken in infrared light over ten years, beginning in 2003 when Spitzer launched. Glimpse 360, NASA Jet Propulsion Laboratory

NASA Jet Propulsion Laboratory (YouTube Channel)
NASA Jet Propulsion Laboratory (Official Website)

Glimpse 360 (NASA Jet Propulsion Laboratory)

Hubble Skymap puts the night sky at your fingertips any time of day. Roam the Milky Way to find a selection of stars and nebulae as seen by Hubble. To explore the skymap, scroll, double click, or pinch/swipe to zoom in and out. Roll over an icon to see the object, click to zero in, and click again for a detailed view and a description. Drag the map to navigate. — Hubble Skymap (NASA Science)

Hubble Skymap (NASA Science)

Articles about the Milky Way Galaxy (Big Think)
Talks about the Milky Way Galaxy (TED: Ideas Worth Spreading)

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Innovation

Science

Galactic Astronomy is the study of the Milky Way galaxy and all its contents. This is in contrast to extragalactic astronomy, which is the study of everything outside our galaxy, including all other galaxies. The Milky Way galaxy, where the Solar System is located, is in many ways the best-studied galaxy, although important parts of it are obscured from view in visible wavelengths by regions of cosmic dust. The development of radio astronomy, infrared astronomy and submillimetre astronomy in the 20th century allowed the gas and dust of the Milky Way to be mapped for the first time. — Wikipedia

European Space Agency (YouTube Channel)
European Space Agency (Official Website)

Gaia Sees Strange Stars in Most detailed Milky Way Survey to Date (European Space Agency)

NASA Goddard (YouTube Channel)
Goddard Space Flight Center (Official Website)

Hubble Space Telescope (NASA Missions)

The Milky Way and Andromeda galaxies are expected to collide in ~4.5 billion years, merging to form a giant elliptical galaxy or a large disc galaxy. With an apparent magnitude of 3.4, the Andromeda Galaxy is among the brightest of the Messier objects — making it visible to the naked eye on moonless nights, even when viewed from areas with moderate light pollution. — Wikipedia

ScienceAtNASA (YouTube Channel)
NASA Science (Official Website)

This animation depicts the collision between our Milky Way galaxy and the Andromeda galaxy. Hubble Space Telescope observations indicate that the two galaxies, pulled together by their mutual gravity, will crash together about 4 billion years from now. Around 6 billion years from now, the two galaxies will merge to form a single galaxy. The video also shows the Triangulum galaxy, which will join in the collision and perhaps later merge with the Andromeda/Milky Way pair.

NASA Video (YouTube Channel)
NASA (Official Website)

Colliding Galaxies Videos (ViewSpace, Space Telescope Science Institute)
Interacting Galaxies: Future of the Milky Way Interactives (ViewSpace, Space Telescope Science Institute)

The Milky Way Galaxy (JPL, NASA)
Milky Way Galaxy (Imagine the Universe, NASA Goddard Space Flight Center)

Milky Way Videos (ViewSpace, Space Telescope Science Institute)

Observations of the Galactic Centre (Encyclopædia Britannica)

Galactic Astronomy (Eric Weisstein’s World of Astronomy, Wolfram Research)
Milky Way (Wolfram Alpha)

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Preservation

History

Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies. — Wikipedia

Objectivity (YouTube Channel)
Royal Society (YouTube Channel)
Royal Society (Official Site)

How we learned the shape of the Milky Way (Raymond Shubinsk, Astronomy Magazine)
Mapping the Milky Way: William Herschel’s Star-Gages (Todd Timberlake, Berry College)
The Shape of the Milky Way from Starcounts (Penn State College of Earth and Mineral Sciences)
Discovery of the Milky Way (G. H. Rieke, University of Arizona)
Herschel and the Milky Way (Encyclopædia Britannica)

Library

DDC: 523.113 The Milky Way (Library Thing)
Subject: Milky Way (Library Thing)

Subject: Milky Way (Open Library)

LCC: QB 857.7 Milky Way (Library of Congress)
Subject: Milky Way (Library of Congress)

Subject: Milky Way (WorldCat)

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Participation

Education

The Milky Way Galaxy (Ology, American Museum of Natural History)
Milky Way (Cosmos4Kids)

The Milky Way (Crash Course Astronomy, YouTube Video

Milky Way (Astronomy Center, ComPADRE)

MERLOT: Multimedia Educational Resource for Learning and Online Teaching
OER Commons: Open Educational Resources

Community

News

Milky Way (Nova Research Highlights, American Astronomical Society)
Milky Way (Astronomy Magazine)
Milky Way Galaxy (JSTOR)
Milky Way (Phys.org)

Recent News from Phys.org …

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