FIVE CONCENTRIC RINGS AROUND THE BLACK HOLE V404CYG

Image Credit: G. Vasilopoulos & M. Petropoulou.
RGB image of the X-ray dust scattered rings observed by Swift/XRT. The Swift/XRT field-of-view is enclosed by the green circle, while a white circle of radius 9′ is overplotted for guiding the eye. The black hole is located at the center of the rings.

First detection of X-ray dust scattered rings from the Galactic low mass X-ray binary V404 Cyg. The observation of the system with Swift/XRT on June 30 2015 revealed the presence of five concentric ring-like structures centred at the position of V404 Cyg.

A low-mass X-ray binary (LMXB) is a binary star where one of the components is either a black hole or neutron star. The X-rays are produced by matter falling from the donor star that usually is a relatively normal star less massive than the compact object.
V404 Cyg is an X-ray transient source with three confirmed historical outbursts in 1936, 1958 and 1989. The black hole has an estimated mass of ~12 solar mass. The donor star has a mass of ∼1 solar mass and it is a late type G or early type K star (it is similar to our sun).

The study of the rings can provide information for the properties of the interstellar medium and the dust distribution in the direction of the black hole.

► Read more>>
http://arxiv.org/pdf/1511.00932v1.pdf
http://mnras.oxfordjournals.org/content/455/4/4426.abstract

► Image Credit:
G. Vasilopoulos & M. Petropoulou

Comments

SUPERNOVAE FROM WD-WD DIRECT COLLISIONS

Image: Supernova remnant N 63A. Credit: NASA/ESA/HEIC and The Hubble Heritage Team (STScI/AURA) Models for supernovae (SNe) related to thermonuclear explosions of white dwarfs (WDs) have been extensively studied over the last few decades, mostly focusing on single degenerate (accretion of material of a WD) and double degenerate (WD-WD merger) scenarios.

A SIGNIFICATIVE FRACTION OF BARYONS RESIDE IN THE FILAMENTS OF THE COSMIC WEB

(Credit: NASA, ESA, and E. Hallman (University of Colorado, Boulder) Observations of the cosmic microwave background indicate that baryons (protons, neutrons, etc., - the ordinary matter just to understand) occupies only 5% of the total energy content of the Universe (95% is dark matter and dark energy). However in the local universe approximately half of this "ordinary" matter it has never been observed.

Atmospheric Beacons Guide NASA Scientists in Search for Life

Beacons of life could help researchers identify potentially habitable worlds. Credits: NASA’s Goddard Space Flight Center/Mary Pat Hrybyk Some exoplanets shine brighter than others in the search for life beyond the solar system. New NASA research proposes a novel approach to sniffing out exoplanet atmospheres. It takes advantage of frequent stellar storms — which hurl huge clouds of stellar material and radiation into space — from cool, young dwarf stars to highlight signs of habitable exoplanets. Traditionally, researchers have sought potential biosignatures as ways of identifying inhabited worlds: byproducts from life as we know it such as oxygen or methane that over time accumulate in the atmosphere to detectable amounts. But with current technology, according to Vladimir Airapetian, lead author of a Nature Scientific Reports study published on Nov. 2, 2017, identifying these gases on distant terrestrial exoplanets is time-consuming, requiring days of observation time. The ne...

SpaceTime

Search This Blog