Featured Research

from universities, journals, and other organizations

Lost And Found: Hubble Finds Much Of The Universe's Missing Hydrogen

Date:
May 4, 2000
Source:
Space Telescope Science Institute
Summary:
For the past decade astronomers have looked for vast quantities of hydrogen that were cooked-up in the Big Bang but somehow managed to disappear into the empty blackness of space. Now, NASA's Hubble Space Telescope has uncovered this long-sought missing hydrogen. It accounts for nearly half of the "normal" matter in the universe -- the rest is locked up in myriad galaxies.

For the past decade astronomers have looked for vast quantities of hydrogen that were cooked-up in the Big Bang but somehow managed to disappear into the empty blackness of space.

Related Articles


Now, NASA's Hubble Space Telescope has uncovered this long-sought missing hydrogen. It accounts for nearly half of the "normal" matter in the universe -- the rest is locked up in myriad galaxies.

Astronomers believe at least 90 percent of the matter in the universe is hidden in exotic "dark" form that has not yet been seen directly. But more embarrassing is that, until now, they have not been able to see most of the universe's ordinary, or baryonic, matter (normal protons, electrons and neutrons).

The confirmation of this missing hydrogen will shed new light on the large-scale structure of the universe. The detection also confirms fundamental models of how much hydrogen was manufactured in the first few minutes of the universe's birth in the Big Bang.

"This is a successful, fundamental test of cosmological models," said Todd Tripp of Princeton University, Princeton, NJ. "This provides strong evidence that the models are on the right track." The results of Tripp and his collaborators, Edward Jenkins from Princeton and Blair Savage from the University of Wisconsin-Madison, are being published in the May 1 issue of the Astrophysical Journal Letters.

Previous observations show that billions of years ago this missing matter formed vast complexes of hydrogen clouds -- but since then has vanished. Even Hubble's keen eye didn't see the hydrogen directly because it is too hot and rarified. Instead, Hubble found a telltale elemental tracer -- highly ionized (energized) oxygen -- between galaxies, which the hydrogen heats to the temperatures observed in intergalactic space. The presence of highly ionized oxygen between the galaxies implies there are huge quantities of hydrogen in the universe, which is so hot it escapes detection by normal observational techniques.

In recent years, supercomputer models of the expanding, evolving universe have predicted an intricate web of gas filaments where hydrogen is concentrated along vast chain-like structures. Clusters of galaxies form where the filaments intersect. The models predict that vast hydrogen clouds flowing along the chains should collide and heat up. This would squelch the formation of more galaxies in the hottest regions, so star birth was more abundant in the early universe when the hydrogen was cool enough to coalesce.

The oxygen "tracer" was probably created when exploding stars in galaxies spewed the oxygen (created in their cores through nuclear fusion) back into intergalactic space where it mixed with the hydrogen and then was shocked and heated to temperatures over 360,000 degrees Fahrenheit (100,000 degrees Kelvin).

Astronomers detected the highly ionized oxygen by using the light of a distant quasar to probe the invisible space between the galaxies, like shining a flashlight beam through a fog. Hubble's Space Telescope Imaging Spectrograph found the spectral "fingerprints" of intervening oxygen superimposed on the quasar's light. Slicing across billions of light-years of space, the quasar's brilliant beam penetrated at least four separate filaments of the invisible hydrogen laced with the telltale oxygen.

Hubble's ultraviolet sensitivity and high-resolution spectroscopic capability allowed it to probe the nearby universe, where spectral features of hot gas can be seen at ultraviolet wavelengths and the problems faced by X-ray astronomers are avoided. "This result beautifully illustrates the power of spectroscopy for revealing fundamental information about the presence and nature of the gaseous matter in the universe," according to Hubble spectroscopist Blair Savage.

Still, the hot hydrogen could not be seen directly because it is fully ionized and so the hydrogen atoms are stripped of their electrons. Without electrons, no spectral features were etched into the quasar's earth-bound light. The oxygen is highly ionized too, but still retains a few electrons which absorb specific colors from the quasar's light.

NOTE TO EDITORS: A ground-based image and illustration associated with this release are available on the Internet at: http://hubble.stsci.edu/go/news


Story Source:

The above story is based on materials provided by Space Telescope Science Institute. Note: Materials may be edited for content and length.


Cite This Page:

Space Telescope Science Institute. "Lost And Found: Hubble Finds Much Of The Universe's Missing Hydrogen." ScienceDaily. ScienceDaily, 4 May 2000. <www.sciencedaily.com/releases/2000/05/000503182254.htm>.
Space Telescope Science Institute. (2000, May 4). Lost And Found: Hubble Finds Much Of The Universe's Missing Hydrogen. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2000/05/000503182254.htm
Space Telescope Science Institute. "Lost And Found: Hubble Finds Much Of The Universe's Missing Hydrogen." ScienceDaily. www.sciencedaily.com/releases/2000/05/000503182254.htm (accessed October 30, 2014).

Share This



More Space & Time News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Antares Liftoff Explosion

Raw: Antares Liftoff Explosion

AP (Oct. 29, 2014) Observers near Wallops Island recorded what they thought would be a routine rocket launch Tuesday night. What they recorded was a major rocket explosion shortly after lift off. (Oct 29) Video provided by AP
Powered by NewsLook.com
Raw: Russian Cargo Ship Docks at Space Station

Raw: Russian Cargo Ship Docks at Space Station

AP (Oct. 29, 2014) Just hours after an American cargo run to the International Space Station ended in flames, a Russian supply ship has arrived at the station with a load of fresh supplies. (Oct. 29) Video provided by AP
Powered by NewsLook.com
Journalist Captures Moment of Antares Rocket Explosion

Journalist Captures Moment of Antares Rocket Explosion

Reuters - US Online Video (Oct. 29, 2014) A space education journalist is among those who witness and record the explosion of an unmanned Antares rocket seconds after its launch. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
Rocket Explosion Under Investigation

Rocket Explosion Under Investigation

AP (Oct. 28, 2014) NASA and Orbital Sciences officials say they are investigating the explosion of an unmanned commercial supply rocket bound for the International Space Station. It blew up moments after liftoff Tuesday evening over the launch site in Virginia. (Oct. 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins