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Titan up close
Scientists reveal stunning pictures of Saturn's moon Titan and other results during this news conference from July 3. (38min 17sec file)
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Saturn ring pictures
Cassini's stunning close-up images of the rings around Saturn, taken just after the craft entered orbit Thursday morning, are presented with expert narration by Carolyn Porco, the mission imaging team leader. (8min 39sec file)
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Burn ignition!
Mission control erupts in applause as communications from Cassini confirm the orbit insertion burn has begun. (60sec file)
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Burn completed
Signals from Cassini announce the conclusion of the Saturn orbit insertion burn, confirming the spacecraft has arrived at the ringed planet. (2min 15sec file)
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Post-arrival briefing
Mission officials hold a post-orbit insertion burn news conference at 1 a.m. EDT July 1 to discuss Cassini's successful arrival at Saturn. (25min 27sec file)
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International cooperation
Officials from the U.S., European and Italian space agencies discuss the international cooperation in the Cassini mission and future exploration projects during this news conference from 2 p.m. EDT June 30. (19min 35sec file)
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'Ring-side' chat
This informal "ring-side chat" from 5 p.m. EDT June 30 discusses the Cassini mission to Saturn and the future of space exploration. (49min 20sec file)
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Glimpse at early universe reveals surprise
JOHNS HOPKINS UNIVERSITY NEWS RELEASE
Posted: July 7, 2004

A rare glimpse back in time into the universe's early evolution has revealed something startling: mature, fully formed galaxies where scientists expected to discover little more than infants.

"Up until now, we assumed that galaxies were just beginning to form between 8 and 11 billion years ago, but what we found suggests that that is not the case," said Karl Glazebrook, associate professor of physics and astronomy in the Krieger School of Arts and Sciences at The Johns Hopkins University in Baltimore and co-principal author of a paper in the July 8 issue of Nature. "It seems that an unexpectedly large fraction of stars in big galaxies were already in place early in the universe's formation, and that challenges what we've believed. We thought massive galaxies came much later."

Using the Frederick C. Gillett Gemini North Telescope in Mauna Kea, Hawaii, Glazebrook and a multinational team of researchers called the Gemini Deep Deep Survey (GDDS) employed a special technique called the "Nod and Shuffle" to peer into what had traditionally been a cosmological blind spot. Called "the Redshift Desert," this era - 8 billion to 11 billion years ago, when the universe was only 3 billion to 6 billion years old - has remained relatively unexplored until now, mainly because of the challenges inherent in collecting data from the faintest galactic light ever to be dissected into the rainbow of colors called a spectrum. In all, the team collected and analyzed spectra from 300 galaxies, making it the most complete sample ever taken from the Redshift Desert.

"This was the most comprehensive survey ever done covering the bulk of the galaxies that represent conditions in the early universe," Glazebrook said. "We expected to find basically zero massive galaxies beyond about 9 billion years ago, because theoretical models predict that massive galaxies form last. Instead, we found highly developed galaxies that just shouldn't have been there, but are."

These findings challenge the dominant theory of galactic evolution, which posits that at this early stage, galaxies should have formed from the bottom up, with small pieces crashing together to build small and then ever larger galaxies. Called the "hierarchical model," this scenario predicts that normal-to-large galaxies such as those studied by GDDS would not yet exist.

"There are obviously some aspects of the early lives of galaxies that we don't yet completely understand, Glazebrook said. "We do find fewer massive galaxies in the past, but there are still more than we expected. This result is giving us a big clue as to how stars form from invisible gas in the hierarchical model, which is something not well understood under current theories. Some new ingredient is required to make more stars form earlier in the big galaxies. But what that ingredient is, we don't yet know."

The GDDS team, which included Nature paper co-authors Roberto Abraham from the University of Toronto, Patrick McCarthy from the Observatories of the Carnegie Institution of Washington and David Crampton of the National Research Council of Canada's Herzberg Institute of Astrophysics, was supported by a grant from the Packard Foundation and by institutional support from the National Science Foundation, Canada's National Research Council, the Natural Sciences and Engineering Research Council of Canada and the United Kingdom's Particle Physics and Research Council, among others.

Ares 1-X Patch
The official embroidered patch for the Ares 1-X rocket test flight, is available for purchase.
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Apollo Collage
This beautiful one piece set features the Apollo program emblem surrounded by the individual mission logos.
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Expedition 21
The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.
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Hubble Patch
The official embroidered patch for mission STS-125, the space shuttle's last planned service call to the Hubble Space Telescope, is available for purchase.
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