NASA Logo, External Link
Facebook icon, External Link to NASA STI page on Facebook Twitter icon, External Link to NASA STI on Twitter YouTube icon, External Link to NASA STI Channel on YouTube RSS icon, External Link to New NASA STI RSS Feed AddThis share icon
 

Record Details

Record 28 of 559
More Hidden Black Hole Dangers
Offline Availability: Go to Request Form
Author and Affiliation:
Wanjek, Christopher(NASA Goddard Space Flight Center, Greenbelt, MD, United States)
Abstract: Black holes such as GRO J1655-40 form from collapsed stars. When stars at least eight times more massive than our Sun exhaust their fuel supply, they no longer have the energy to support their tremendous bulk. These stars explode as supernovae, blasting their outer envelopes into space. If the core is more than three times the mass of the Sun, it will collapse into a singularity, a single point of infinite density.Although light cannot escape black holes, astronomers can see black holes by virtue of the hot, glowing gas often stolen from a neighboring star that orbits these objects. From our vantage point, the light seems to flicker. The Rossi Explorer has recorded this flickering (called quasiperiodic oscillations, or QPOs) around many black holes. QPOs are produced by gas very near the innermost stable orbit the closest orbit a blob of gas can maintain before falling pell-mell into the black hole. As gas whips around the black hole at near light speed, gravity pulls the gas in one direction, then another, adding to the flickering. The QPO is related to the speed and size of this orbit and the mass of the black hole.
Publication Date: Jan 01, 2003
Document ID:
20040010581
(Acquired Feb 06, 2004)
Subject Category: LUNAR AND PLANETARY SCIENCE AND EXPLORATION
Document Type: Technical Report
Publication Information: Space Science Reference Guide, 2nd Edition; (LPI-Contrib-1154); (SEE 20040010556)
Financial Sponsor: NASA Goddard Space Flight Center; Greenbelt, MD, United States
Organization Source: NASA Goddard Space Flight Center; Greenbelt, MD, United States
Description: 3p; In English; Original contains color illustrations
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright; Distribution under U.S. Government purpose rights
NASA Terms: BLACK HOLES (ASTRONOMY); GRAVITATIONAL COLLAPSE; OSCILLATIONS; HIGH TEMPERATURE GASES; LUMINESCENCE
Miscellaneous Notes: Repr. from Mercury Magazine, v. 30, no. 4, July/August 2001
› Back to Top
Find Similar Records
NASA Logo, External Link
NASA Official: Gerald Steeman
Site Curator: STI Program
Last Modified: September 30, 2017
Contact Us