Tracing the Growth of Galaxies - NASA Science

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Like documenting a child’s development in a scrapbook, astronomers use Hubble to capture the appearance of many developing galaxies throughout cosmic time. This is possible because of the relationship between cosmic distance and time: the deeper Hubble peers into space, the farther back it looks in time. The most distant and earliest galaxies spotted by Hubble are smaller and more irregularly shaped than today’s grand spiral and elliptical galaxies. This is evidence that galaxies grew over time through mergers with other galaxies to become the giant systems we see today.

Taken over the course of 10 days in 1995, the Hubble Deep Field captured roughly 3,000 distant galaxies varying in their stages of evolution, stunning the world. This video features some of the scientists and engineers that work on Hubble, and how the Hubble Deep Field changed everything. Credit: NASA’s Goddard Space Flight Center; Lead Producer and Editor: Paul Morris

This scientific visualization flies through a 3D model of the Hubble Ultra Deep Field of galaxies. Each of the more than 5,000 galaxies in the model was cut out of the HUDF image and placed at its appropriate distance (as calculated from redshift measurements). The virtual camera flies through this long, thin galaxy dataset, showing how galaxy sizes, shapes, and colors change as one looks both out in space and back in time. Note that, in order to traverse the cosmos in a reasonable amount of time, the distance scale in the model was compressed by a factor of a few hundred.

NASA, ESA, and G. Bacon, T. Borders, L. Frattare, Z. Levay and F. Summers (STScI)

Hubble Ultra Deep Field

The Hubble Ultra Deep Field contains an estimated 10,000 galaxies. In ground-based images, the patch of sky in which these galaxies reside (roughly the area of sky seen through the eye of a needle held at arm’s length) is largely empty. Hubble’s deep field view uncovered a menagerie of galaxy types, shapes, sizes, and ages that help us chart how galaxies evolve over time.

NASA’S Hubble Provides First Census of Galaxies Near Cosmic Dawn

Hubble Ultra Deep Field (detail)
NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)
Andromeda Galaxy and the Milky Way Collision

Hubble observations of our neighbor, the Andromeda galaxy (M31), show that the galaxy is moving ever closer to an inevitable collision with our own Milky Way. Andromeda is currently 2.5 million light-years away, but it and the Milky Way are moving toward each other under the mutual pull of gravity between the two galaxies and the invisible dark matter that surrounds them both. The merger will begin about 4 billion years from now and will likely result in the creation of a giant elliptical galaxy.

NASA’s Hubble Shows Milky Way is Destined for Head-On Collision

This illustration shows a stage in the predicted merger between our Milky Way galaxy and the neighboring Andromeda galaxy, as it will unfold over the next several billion years.
NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger

This simulation shows the view of the night sky throughout the merger of our Milky Way galaxy and the neighboring Andromeda galaxy.
NASA, ESA, Z. Levay, R. van der Marel and G. Bacon (STScI), T. Hallas and A. Mellinger

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Hubble’s Deepest View Ever of the Universe Unveils Earliest Galaxies

Hubble’s Ultra Deep Field is a million-second-long exposure revealing the first galaxies to emerge from the so-called “dark ages,” the time shortly after the big bang when the first stars reheated the cold, dark universe.

faint, distant galaxies, observed by Hubble

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Hubble’s time machine

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The eXtreme Deep Field was assembled by combining 10 years of Hubble photographs taken of a patch of sky at the center of the original Hubble Ultra Deep Field.

illustration of merging galaxies in night sky with rocky landscape silhouette in foreground

Hubble Shows Milky Way is Destined for Head-On Collison with Andromeda Galaxy

Hubble measurements of the motion of Andromeda show the galaxy is now 2.5 million light-years away, but it is falling toward the Milky Way under the mutual pull of gravity between the two galaxies and the invisible dark matter that surrounds them both.

Black background peppered with blue-white stars and distant rusty-orange-red galaxies. center of image: bright star that holds a gaseous, blue, elongated, amorphous mass peppered with white stars just to the right of the star.

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Discover the breadth and depth of Hubble's exciting discoveries!

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Hubble image of the Crab Nebula

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Artist's impression of the ten hot Jupiter exoplanets. Two rows of exoplanet illustrations. There are 5 planets of varying sizes, colors, and atmospheric features in each row.

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Comma shaped curved cloud of gases in bright white edged with bright-pink star forming regions, and threaded with rusty-brown tendrils of dust at center and throughout the comma shaped merger. All set against the black of deep space.

Galaxy Details and Mergers

Galaxies evolve through gravitational interaction with their neighbors, creating a menagerie of forms.

Computer simulation of a supermassive black hole at the core of a galaxy. Center is a black circle. Surrounding the black circle are arcs of red, blue, orange, and white. Further out from the circle are blotches of red, blue, orange, and white representing celestial objects.

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Six Hubble images in a grid of three across and two down. Each is a gamma-ray burst in a host galaxy. The images are orange-red and white with hints of yellow.

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Cepheid star in Andromeda galaxy (Hubble observations)

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A field of galaxies along with the curved arcs of gravitationally lensed galaxies.

Focusing in on Gravitational Lenses

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A cluster of galaxies fills the frame. A purple glow around the largest concentrations of galaxies indicates the distribution of dark matter.

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Top: Three views going back in time show slices of the cosmos. Bottom: A computer simulated, 3-D map of the distribution of dark matter.

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