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Hubble Probes the Distant Past

Fuzzy orange blobs on black, with a blue arc around one
ESA/Hubble & NASA; acknowledgment: Judy Schmidt (Geckzilla)

Obtained for a research program on star formation in old and distant galaxies, this NASA/ESA (European Space Agency) Hubble Space Telescope image taken with the Wide Field Camera 3 (WFC3) demonstrates the immense effects of gravity; more specifically, it shows the effects of gravitational lensing caused by a galaxy cluster called SDSS J1152+3313.

Gravitational lenses — such as this galaxy cluster — possess immense masses that warp their surroundings and bend the light from faraway objects into rings, arcs, streaks, blurs and other odd shapes. This lens is bending the light from a more distant galaxy into a grand arc, which is blue because of the energetic star formation activity in the galaxy. The lens, however, is not only warping the appearance of the distant galaxy — it is also amplifying its light, making it appear much brighter than it would be without the lens. Combined with the high image quality obtainable with Hubble, this gives valuable clues into how stars formed in the early universe.

Star formation is a key process in astronomy. Everything that emits light is somehow connected to stars, so understanding how stars form is key to understanding countless objects lying across the cosmos. Astronomers can probe these early star-forming regions to learn about the sizes, luminosities, formation rates and generations of different types of stars.

Text Credit: ESA