Featured Research

from universities, journals, and other organizations

All-you-can-eat at the end of the universe: How early black holes could have grown to billions of times the mass of our sun

Date:
August 11, 2014
Source:
Weizmann Institute of Science
Summary:
A new model shows how early black holes could have grown to billions of times the mass of our sun. These giant bodies -- quasars -- feed on interstellar gas, swallowing large quantities of it non-stop. Thus they reveal their existence: The light that is emitted by the gas as it is sucked in and crushed by the black hole's gravity travels for eons across the Universe until it reaches our telescopes. Looking at the edges of the Universe is therefore looking into the past. These far-off, ancient quasars appear to us in their "baby photos" taken less than a billion years after the Big Bang: monstrous infants in a young Universe.

A small black hole gains mass: Dense cold gas (green) flows toward the center of a stellar cluster (red cross in blue circle) with stars (yellow); the erratic path of the black hole through the gas (black line) is randomized by the surrounding stars.
Credit: Image courtesy of Weizmann Institute of Science

At the ends of the Universe there are black holes with masses equaling billions of our sun. These giant bodies -- quasars -- feed on interstellar gas, swallowing large quantities of it non-stop. Thus they reveal their existence: The light that is emitted by the gas as it is sucked in and crushed by the black hole's gravity travels for eons across the Universe until it reaches our telescopes. Looking at the edges of the Universe is therefore looking into the past. These far-off, ancient quasars appear to us in their "baby photos" taken less than a billion years after the Big Bang: monstrous infants in a young Universe.

Normally, a black hole forms when a massive star, weighing tens of solar masses, explodes after its nuclear fuel is spent. Without the nuclear furnace at its core pushing against gravity, the star collapses: Much of the material is flung outwards in a great supernova blast, while the rest falls inward, forming a black hole of only about 10 solar masses.

Since these ancient quasars were first discovered, scientists have wondered what process could lead a small black hole to gorge and fatten to such an extent, so soon after the Big Bang.

In fact, several processes tend to limit how fast a black hole can grow. For example, the gas normally does not fall directly into the black hole, but gets sidetracked into a slowly spiraling flow, trickling in drop by drop. When the gas is finally swallowed by the black hole, the light it emits pushes out against the gas. That light counterbalances gravity, and it slows the flow that feeds the black hole.

So how, indeed, did these ancient quasars grow? Prof. Tal Alexander, Head of the Particle Physics and Astrophysics Department, proposes a solution in a paper written together with Prof. Priyamvada Natarajan of Yale University, which recently appeared in Science.

Their model begins with the formation of a small black hole in the very early Universe. At that time, cosmologists believe, gas streams were cold, dense, and contained much larger amounts of material than the thin gas streams we see in today's cosmos. The hungry, newborn black hole moved around, changing direction all the time as it was knocked about by other baby stars in its vicinity. By quickly zigzagging, the black hole continually swept up more and more of the gas into its orbit, pulling the gas directly into it so fast, the gas could not settle into a slow, spiraling motion. The bigger the black hole got, the faster it ate; this growth rate, explains Alexander, rises faster than exponentially. After around 10 million years -- a blink of an eye in cosmic time -- the black hole would have filled out to around 10,000 solar masses. From then, the colossal growth rate would have slowed to a somewhat more leisurely pace, but the black hole's future path would already be set -- leading it to eventually weigh in at a billion solar masses or more.


Story Source:

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


Journal Reference:

  1. T. Alexander, P. Natarajan. Rapid growth of seed black holes in the early universe by supra-exponential accretion. Science, 2014; DOI: 10.1126/science.1251053

Cite This Page:

Weizmann Institute of Science. "All-you-can-eat at the end of the universe: How early black holes could have grown to billions of times the mass of our sun." ScienceDaily. ScienceDaily, 11 August 2014. <www.sciencedaily.com/releases/2014/08/140811124824.htm>.
Weizmann Institute of Science. (2014, August 11). All-you-can-eat at the end of the universe: How early black holes could have grown to billions of times the mass of our sun. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2014/08/140811124824.htm
Weizmann Institute of Science. "All-you-can-eat at the end of the universe: How early black holes could have grown to billions of times the mass of our sun." ScienceDaily. www.sciencedaily.com/releases/2014/08/140811124824.htm (accessed September 16, 2014).

Share This



More Space & Time News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

East Coast Treated To Rare Meteor Sighting

East Coast Treated To Rare Meteor Sighting

Newsy (Sep. 16, 2014) — Numerous residents along the East Coast reported seeing a bright meteor flash through the sky Sunday night. Video provided by Newsy
Powered by NewsLook.com
Space Race Pits Bezos Vs Musk

Space Race Pits Bezos Vs Musk

Reuters - Business Video Online (Sep. 16, 2014) — Amazon CEO Jeff Bezos' startup will team up with Boeing and Lockheed to develop rocket engines as Elon Musk races to have his rockets certified. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
NASA’s Curiosity Rover Finally Reaches Long-Term Goal

NASA’s Curiosity Rover Finally Reaches Long-Term Goal

Newsy (Sep. 15, 2014) — After more than two years, NASA’s Mars Curiosity Rover reached Mount Sharp, its long-term destination. Video provided by Newsy
Powered by NewsLook.com
SpaceX's Elon Musk Really Wants To Colonize Mars

SpaceX's Elon Musk Really Wants To Colonize Mars

Newsy (Sep. 14, 2014) — Elon Musk has been talking about his goal of colonizing Mars for years now, but how much of it does he actually have figured out, and is it possible? Video provided by Newsy
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:
from the past week

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