Webb’s observations will trace dusty galaxies from the first billion years of the universe.
The brightest objects in the distant, young universe are quasars. These cosmic beacons are powered by a supermassive black hole that consumes material at a fierce rate. The quarars are so clear that they can surpass their entire host galaxy, making it difficult to study those galaxies and compare them to galaxies without quarars.
A new theoretical study examines how well NASAcoming soon James Webb Space Telescope, scheduled to launch in 2021, will be able to separate the light of host galaxies from the bright central quasar. Researchers have found that Webb can find host galaxies that exist only a billion years after the big bang.
This video zooms in on a detailed simulation of the universe called BlueTides. Like the iconic Powers of Ten video, each step covers a distance 10 times smaller than the previous one. The first frame covers about 200 million light-years while the fourth and final frame covers only 200,000 light-years and contains two galaxies. The researchers used this simulation to investigate the properties of galaxies containing quasars – bright galactic cores powered by the accumulation of supermassive black holes. Credits: Y. Ni (Carnegie Mellon University) and L. Hustak (STScI)
Quarries are the brightest thing in the universe and are among the most industrious. They have gone through entire galaxies of billions of stars. A supermassive Black hole bound in the middle of each quasar, but not every black hole is a quasar. Only black holes that feed abundantly can give strength to a quasar. The material falling into the superb black hole heats up and causes a quasar to shine throughout the universe like a lighthouse beacon.
Although quasars are known to live in the centers of galaxies, it is difficult to say what those galaxies look like and how they compare to galaxies without quarries. The challenge is the stare of the quasar that makes it difficult or impossible to tempt the light of the surrounding host galaxy. It’s like looking directly at a car headlight and trying to figure out what kind of vehicle it is attached to.
A new study suggests that NASA’s James Webb Space Telescope, scheduled to launch in 2021, could reveal host galaxies of several distant quasars despite their small size and obscure dust.
“We want to know what kind of galaxies those quasars live in. That will help us answer questions like: How can holes grow so fast? Is there a connection between the mass of the galaxy and the mass? of black holes, as we see in the surrounding universe? “said lead author Madeline Marshall of the University of Melbourne in Australia, who performed her work within the ARC Center of Excellence at All Sky Astrophysics at 3 Dimensions.
Answering these questions is difficult for a number of reasons. In particular, the farther away a galaxy is, the more light it has stretched over the longer wavelengths of the expanding universe. As a result, ultraviolet light from the black hole accretion disk or young galaxy stars is transferred to infrared wavelengths.
In a recent study, astronomers used NASA’s near-infrared capabilities Hubble Space Telescope to study known quasars in the hope of seeing the surrounding luster of their host galaxies, without significant detections. This indicates that the dust inside the galaxies obscures the light of their stars. Webb’s infrared detectors can penetrate dust and discover hidden galaxies.
“Hubble doesn’t go far enough in the infrared to see host galaxies. This is where Webb really comes from,” said Rogier Windhorst of Arizona State University in Tempe, a co-author of the Hubble study.
To determine what Webb is expected to see, the team used a state-of-the-art computer simulation called BlueTides, developed by a team led by Tiziana Di Matteo at Carnegie Mellon University in Pittsburgh, Pennsylvania.
“BlueTides is designed to study the formation and development of galaxies and quasars in the first billion years of the universe’s history. The vast amount of cosmic and high spatial resolution allows us to study the rare hosts of this quasar statistically, “said Yueying Ni of Carnegie Mellon University, who ran the BlueTides simulation. BlueTides provides a good deal of insight into current observations and allows astronomers to predict what Webb should see.
The team found that the galaxies that host the quarries are smaller than average, reaching only 1/30 of the width of Milky Way despite containing almost as much as our galaxy. “The host galaxy was surprisingly small compared to the average galaxy at that point in time,” Marshall said.
The galaxies in the simulation tend to form stars rapidly, up to 600 times faster than the current star formation rate in the Milky Way. “We learned that these systems are growing very fast. They look like precocious children – they do everything early,” explained co-author Di Matteo.
The team used these simulations to determine what Webb cameras would see if the observatory studied these distant systems. They found it possible to identify the host galaxy from the quasar, though still challenging due to the small size of the galaxy in the sky.
“Webb will open up the opportunity to observe them in the farthest host galaxy for the first time,” Marshall said.
They also consider what Webb spectrographs can get from these systems. Spectral studies, which break down incoming light into substance colors or lengths, may reveal the chemical composition of dust in these systems. Studying how much heavy elements they contain can help astronomers understand their history of star formation, since most of the chemical elements are made from stars.
Webb can also determine if host galaxies are isolated or not. The Hubble study found that most quarars have searchable companion galaxies, but could not determine if those galaxies were really close or if they were superposition opportunities. Webb’s spectral capabilities allow astronomers to measure redshifts, and thus the distance, of bright companion galaxies to determine if they are within the same distance of the quasar.
Ultimately, Webb’s observations should provide new insights into these extreme systems. Astronomers are still struggling to understand how a black hole could grow to weigh a billion times larger than our Sun in just one billion years. “These big black holes should not exist in advance because there is not enough time for them to grow enormously,” said co-author Stuart Wyithe of the University of Melbourne.
Future studies of quasar will also strengthen synergies in many upcoming observatories. Infrared surveys include the European Space Agency’s Euclid mission, as well as the ground-based Vera C. Rubin Observatory, a National Science Foundation / Department of Energy facility currently operating in Cerro Pachón in Chile of the Atacama Desert. Both observatories significantly increase the number of known distant quarars. Those newly discovered quasars will be reviewed by Hubble and Webb to gain new insights into the formative years of the universe.
- “The host galaxies of z = 7 quasars: predictions from the BlueTides simulation” by Madeline A Marshall, Yueying Ni, Tiziana Di Matteo, J Stuart B Wyithe, Stephen Wilkins, Rupert AC Croft and Jussi K Kuusisto, 5 October 2020, Monthly Notices of the Royal Astronomical Society.
DOI: 10.1093 / mnras / staa2982
- “Restrictions on Rest-frame Ultraviolet Emission from Far-infrared-luminous z sime 6 Quasar Host” by MA Marshall, M. Mechtley, RA Windhorst, SH Cohen, RA Jansen, L. Jiang, VR Jones, JSB Wyithe1, X Fan, NP Hathi, K. Jahnke, WC Keel, AM Koekemoer, V. Marian, K. Ren, J. Robinson, HJA Röttgering, RE Ryan Jr., E. Scannapieco, DP Schneider, G. Schneider, BM Smith at H. Yan, August 27, 2020, The Astrophysical Journal.
DOI: 10.3847 / 1538-4357 / abaa4c
The Bluetides simulation (PI project: Tiziana Di Matteo at Carnegie Mellon University) was run at the Blue Waters sustained-petascale computing facility, supported by the National Science Foundation.
The James Webb Space Telescope will be the world’s premier observatory of science when it launches in 2021. Webb will solve mysteries in our solar system, look beyond distant worlds around other stars, and investigate the mysterious structure and origin of our universe and our inner space. Webb is an international program spearheaded by NASA and its partners, ESA (European Space Agency) and the Canadian Space Agency.