(PhysOrg) - Astronomers using the combined power of the Atacama Large Millimeter/submillimeter Array (ALMA) telescope and NASA’s Hubble Space Telescope have discovered a far-flung trio of primitive galaxies nestled inside an enormous blob of primordial gas nearly 13 billion light-years from Earth.
"This exceedingly rare triple system, seen when the Universe was only 800 million years old, provides important insights into the earliest stages of galaxy formation during a period known as ‘Cosmic Dawn,’ when the Universe was first bathed in starlight," said Richard Ellis, the Steele Professor of Astronomy at the California Institute of Technology and member of the research team. "Even more interesting, these galaxies appear poised to merge into a single massive galaxy, which could eventually evolve into something akin to the Milky Way."…
(Image: NASA/Hubble. The image in the upper right is a close-up of Himiko with Hubble. The three infant galaxies are clearly resolved where only one was known to exist before. These objects are extremely energetic, suggesting they are undergoing a period of intense star formation.
CREDIT: NASA/Hubble. The image in the lower right is the same object with additional data from the Spitzer Space Telescope and Subaru Telescope on Mauna Kea in Hawaii. The halo of ionized hydrogen gas is clearly seen surrounding Himiko. Observations with the Atacama Large Millimeter/submillimeter Array (ALMA) telescope did not detect any telltale signature from carbon, suggesting that these three objects may be very primitive and have not had enough time to seed the intergalactic medium with heavy elements. Credit: NASA/Hubble; NASA/Spitzer; NAOJ/Subaru)
Chandra helps confirm evidence of jet in Milky Way’s black hole
(Phys.org) — Astronomers have long sought strong evidence that Sagittarius A* (Sgr A*), the supermassive black hole at the center of the Milky Way, is producing a jet of high-energy particles. Finally they have found it, in new results from NASA’s Chandra X-ray Observatory and the National Science Foundation’s Very Large Array (VLA) radio telescope.
Jets of high-energy particles are found throughout the universe, on large and small scales. They are produced by young stars and by black holes a thousand times larger than the Milky Way’s black hole. They play important roles in transporting energy away from the central object and, on a galactic scale, in regulating the rate of formation of new stars…
Nature Pulls a Fast One - 2 Galaxies Masquerade As 1
by Whitney Clavin
What might look like a colossal jet shooting away from a galaxy turns out to be an illusion. New data from the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) reveal that two galaxies, one lying behind the other, have been masquerading as one.
In a new image highlighting the chance alignment, radio data from the VLA are blue and infrared observations from NASA’s Spitzer Space Telescope and Wide-field Infrared Survey Explorer (WISE) are yellow and orange, respectively. Visible data are also shown, with starlight in purplish blue and heated gas in rose.
The closer galaxy, called UGC 10288, is located 100 million light-years away. It is spiral in shape, but from our viewpoint on Earth, we are seeing its thin edge. The farther galaxy, seen in blue, is nearly 7 billion light-years away. Two giant jets shoot away from this galaxy, one of which is seen above the plane of the closer galaxy’s disk…
This cluster of stars is known as Messier 15, and is located some 35 000 light-years away in the constellation of Pegasus (The Winged Horse). It is one of the oldest globular clusters known, with an age of around 12 billion years.
Both very hot blue stars and cooler golden stars can be seen swarming together in the image, becoming more concentrated towards the cluster’s bright centre. Messier 15 is one of the densest globular clusters known, with most of its mass concentrated at its core. As well as stars, Messier 15 was the first cluster known to host a planetary nebula, and it has been found to have a rare type of black hole at its centre.
This new image is made up of observations from Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys in the ultraviolet, infrared, and optical parts of the spectrum.
Galactic Cirrus clouds billow and obscure the background Universe in this direction. NGC 7497 is seen through partly cloudy skies. These galactic clouds of dust are sculpted by the winds of nearby stars. They are relatively close to us (only hundreds of light years away) and there are few stars in the foreground to hinder of view of them. The color of the clouds is odd due to the fact they are illuminated mostly by diffuse galactic star light.
Image: Adam Block/Mount Lemmon SkyCenter/University of Arizona [high-resolution]
NGC 6946 is a medium-sized, face-on spiral galaxy about 22 million light years away from Earth. In the past century, eight supernovas have been observed to explode in the arms of this galaxy. Chandra observations (purple) have, in fact, revealed three of the oldest supernovas ever detected in X-rays, giving more credence to its nickname of the “Fireworks Galaxy.” This composite image also includes optical data from the Gemini Observatory in red, yellow, and cyan.
Image: X-ray: NASA/CXC/MSSL/R.Soria et al, Optical: AURA/Gemini OBs [high-resolution]
The spectacular swirling arms and central bar of the Sculptor galaxy are revealed in this new view from NASA’s Spitzer Space Telescope. This image is an infrared composite combining data from two of Spitzer’s detectors taken during its early cold, or cryogenic, mission.
Also known as NGC 253, the Sculptor galaxy is part of a cluster of galaxies visible to observers in the Southern hemisphere. It is known as a starburst galaxy for the extraordinarily strong star formation in its nucleus. This activity warms the surrounding dust clouds, causing the brilliant yellow-red glow in the center of this infrared image.
Figure 1 is split into two constituent parts on the right. On the top is a blue glow primarily from the light of stars as seen at the shorter wavelengths of infrared light. In this view, the disk, spiral arms and central bar are easy to see. The lower right image shows the glow of dust at longer infrared wavelengths in green and red. Regions of star formation glow especially bright at the longest wavelengths (red)…
Stars in our part of the Milky Way seem to be doing “the wave,” a new study suggests. The finding comes from an analysis of the motions of more than 70,000 red giant stars that lie within 6500 light-years of Earth—a distance that, in one direction, reaches about one-fourth of the way to the center of the galaxy.
Above the horizontal plane that slices through the center of the galaxy, stars closer to the center of the galaxy than the sun are, in general, moving away from the plane at speeds of 10 kilometers per second or less.
The researchers estimate the galaxy, named z8_GND_5296 and located 13.1 billion years away, formed stars at a rate that was a hundred times more prolific than today’s Milky Way. The find, reported in Nature this week, suggests the early universe may have witnessed more bursts of frenetic star birth than astronomers had thought. The galaxy, photographed by the Hubble Space Telescope and seen, magnified, in the box above, is much brighter than distant galaxies typically are.
Researchers inferred from its red-ultraviolet color that it was rich in “metals”—elements heavier than hydrogen and helium. Because all of those elements originate from fusion reactions in the heart of stars and are spewed out when those stars explode as supernovae, the find suggests that the galaxy had already seen the birth and death of generations of stars by the time the universe was 700 million years old.
ALMA probes mysteries of jets from giant black holes
(PhysOrg) - Two international teams of astronomers have used the power of the Atacama Large Millimeter/submillimeter Array to focus on jets from the huge black holes at the centers of galaxies and observe how they affect their surroundings. They have respectively obtained the best view yet of the molecular gas around a nearby, quiet black hole and caught an unexpected glimpse of the base of a powerful jet close to a distant black hole… (read more)
This image of the star formation region NGC 6334 is one of the first scientific images from the ArTeMiS instrument on APEX. The picture shows the glow detected at a wavelength of 0.35 millimetres coming from dense clouds of interstellar dust grains. The new observations from ArTeMiS show up in orange and have been superimposed on a view of the same region taken in near-infrared light by ESO’s VISTA telescope at Paranal.
Image: ArTeMiS team/Ph. André, M. Hennemann, V. Revéret et al./ESO/J. Emerson/VISTA Acknowledgment: Cambridge Astronomical Survey Unit [high-resolution]
Scientists Unravel Secrets of Monster Black Hole at Center of Milky Way Galaxy
The supermassive black hole last erupted 2 mya, and will again.
by Andrew Fazekas
For years astronomers have been puzzled as to why our Milky Way galaxy’s “volcano”—a supermassive black hole (SMBH) at its core—is dormant today.
It seems the answer may simply be that we didn’t catch the cosmic monster—weighing at least four million times the mass of our sun—feeding at the right time, according to a new study.
"If we had been around to see it two million years ago, the situation would have been very different," said study co-author Philip Maloney of the University of Colorado in Boulder.
"The Milky Way’s black hole was maybe ten million times brighter [then]," he said. "I don’t think anyone really had any expectation that SMBH might vary in luminosity by such a huge factor on such a short—relatively speaking—time scale."…
Enormous arms of hot gas have been revealed in the Coma galaxy cluster in data from NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton. A specially processed Chandra image (pink) has been combined with optical data from the Sloan Digital Sky Survey (white and blue) to highlight these spectacular arms. Researchers think that these arms — which span at least a half million light years — were most likely formed when smaller galaxy clusters had their gas stripped away by the head wind created by the motion of the clusters through the hot gas.
Image: X-ray: NASA/CXC/MPE/J.Sanders et al, Optical: SDSS [high-resolution]
The solar system moves through a local galactic cloud at a speed of 50,000 miles per hour
… creating an interstellar wind of particles, some of which can travel all the way toward Earth to provide information about our neighborhood.
Like the wind adjusting course in the middle of a storm, scientists have discovered that the particles streaming into the solar system from interstellar space have most likely changed direction over the last 40 years. Such information can help us map out our place within the galaxy surrounding us, and help us understand our place in space. The results, based on data spanning four decades from 11 different spacecraft, were published in Science on Sept. 5, 2013.
Vestiges of the interstellar wind flowing into what’s called the heliosphere — the vast bubble filled by the sun’s own constant flow of particles, the solar wind – is one of the ways scientists can observe what lies just outside of our own home, in the galactic cloud through which the solar system travels. The heliosphere is situated near the inside edge of an interstellar cloud and the two move past each other at a velocity of 50,000 miles per hour. This motion creates a wind of neutral interstellar atoms blowing past Earth, of which helium is the easiest to measure…
X-ray observations have more than tripled the number of known black holes in the nearby Andromeda galaxy. Lying just 2.5 million light-years from Earth, Andromeda (main image) is a giant spiral, the largest of the approximately six dozen galaxies populating the so-called Local Group; the Milky Way ranks number two in size and boasts about 50 known black holes.
In the 20 June issue of The Astrophysical Journal, astronomers will report finding 26 likely black holes in the Andromeda galaxy. Although the black holes themselves emit no radiation, material spiraling into them from orbiting stars gets heated to such extreme temperatures that it emits x-rays (inset). With this discovery, Andromeda now has 35 known black holes, each weighing several times more than the sun, plus a far larger one at its center, giving our giant neighbor more known black holes than any other galaxy outside our own.