Early Universe Archives

October 30, 2020October 30, 2020 by Evan Gough

Galaxies Grew Quickly and Early On in the Universe

Artist's illustration of a galaxy in the early universe that is very dusty and shows the first signs of a rotationally supported disk. In this image, the red color represents gas, and blue/brown represents dust as seen in radio waves with ALMA. Many other galaxies are visible in the background, based on optical data from VLT and Subaru. Credit: B. Saxton NRAO/AUI/NSF, ESO, NASA/STScI; NAOJ/Subaru

The behaviour of galaxies in the early Universe attracts a lot of attention from researchers. In fact, everything about the early Universe is under intense scientific scrutiny for obvious reasons. But unlike the Universe’s first stars, which have all died long ago, the galaxies we see around us—including our own—have been here since the early days.

Current scientific thinking says that in the early days of the Universe, the galaxies grew slowly, taking billions of years to become what they are now. But new observations show that might not be the case.

August 18, 2020August 18, 2020 by Matt Williams

This Distorted Circle is Actually a Galaxy That Looked Very Similar to the Milky Way, Shortly After the Big Bang

Astronomers using ALMA, in which the ESO is a partner, have revealed an extremely distant galaxy that looks surprisingly like our Milky Way. The galaxy, SPT0418-47, is gravitationally lensed by a nearby galaxy, appearing in the sky as a near-perfect ring of light.

The most widely accepted cosmological view states that the first galaxies formed about 380–400 million years after the Big Bang. These were made up of young, hot stars that lived fast and died young, causing the galaxies themselves to be turbulent. At least, that was the theory until a European team of astronomers observed a galaxy 12 billion light-years away that closely resembled the Milky Way.

Using the Atacama Large Millimeter-submillimeter Array (ALMA), the team observed the galaxy, SPT0418-47, as it appeared when the Universe was just 1.4 billion years old. Much to their surprise, the team noted that the structure and features of this galaxy were highly evolved and stable, something that contradicts previously-held notions about the nature of galaxies in the early Universe.

July 9, 2020July 10, 2020 by Matt Williams

A Giant Galaxy Seen Lighting Up the Universe Shortly After the Big Bang

An illustration of cosmic expansion. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

About 370,000 years after the Big Bang, the Universe experienced a period that cosmologists refer to as the “Cosmic Dark Ages.” During this period, the Universe was obscured by pervasive neutral gas that obscured all visible light, making it invisible to astronomers. As the first stars and galaxies formed over the next few hundred millions of years, the radiation they emitted ionized this plasma, making the Universe transparent.

One of the biggest cosmological mysteries right now is when “cosmic reionization” began. To find out, astronomers have been looking deeper into the cosmos (and farther back in time) to spot the first visible galaxies. Thanks to new research by a team of astronomers from University College London (UCL), a luminous galaxy has been observed that was reionizing the intergalactic medium 13 billion years ago.

July 8, 2020July 8, 2020 by Evan Gough

What Telescope Will Be Needed to See the First Stars in the Universe? The Ultimately Large Telescope

New results from the NASA/ESA Hubble Space Telescope suggest the formation of the first stars and galaxies in the early Universe took place sooner than previously thought. A European team of astronomers have found no evidence of the first generation of stars, known as Population III stars, when the Universe was less than one billion years old. This artist’s impression presents the early Universe. Image Credit: ESA/Hubble, M. Kornmesser.

The oldest stars in the Universe are cloaked in darkness. Their redshift is so high, we can only wonder about them. The James Webb Space Telescope will be our most effective telescope for observing the very early Universe, and should observe out to z = 15. But even it has limitations.

To observe the Universe’s very first stars, we need a bigger telescope. The Ultimately Large Telescope.

June 1, 2020June 2, 2020 by Matt Williams

Rare “Ring Galaxy” Seen in the Early Universe

One of the greatest benefits to come from space telescopes and ground-based observatories that take advantage of advanced imaging techniques is their ability to see farther into space (and hence, further back in time). In so doing, they are revealing things about the earliest galaxies, which allows astronomers to refine theories of how the cosmos formed and evolved.

For example, new research conducted by the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) has found a “ring galaxy” that existed 11 billion years ago (about 3 billion years after the Big Bang). This extremely rare structure, which the team describes as a “cosmic ring of fire,” is likely to shake up cosmological theories of how the cosmos has changed over time.

May 27, 2020May 27, 2020 by Evan Gough

A Massive Rotating Disc Discovered in the Early Universe

Artist impression of the Wolfe Disk, a massive rotating disk galaxy in the early, dusty universe. Credit: NRAO/AUI/NSF, S. Dagnello

If we want to understand how the Universe evolves, we have to understand how its large structures form and evolve. That’s why astronomers study galaxy formation. Galaxies are enormous structures of stars, planets, gas, dust, and dark matter, and understanding how they form is critical to understanding the Universe itself.

In 2017, astronomers working with ALMA (Atacama Large Millimeter/sub-millimeter Array) discovered an ancient galaxy. This massive rotating disk galaxy was born when the Universe was only about 1.5 billion years old. According to the most accepted understanding of how galaxies form and evolve, it shouldn’t exist.

But there it is.

April 29, 2020April 29, 2020 by Matt Williams

You’re Looking at Spiral Galaxies, Already Forming When the Universe was Just a Baby

Credit: Michele Ginolfi (ALPINE collaboration); ALMA(ESO/NAOJ/NRAO); NASA/JPL-Caltech/R. Hurt (IPAC)

One of the most exciting developments in astronomy today is the way that advanced arrays and techniques are letting astronomers see farther back in time to the earliest periods of the Universe. In so doing, astronomers hope to get a closer at the earliest galaxies to learn more about how and when they first emerged – which can tell us a great deal more about their subsequent evolution.

This was the purpose of the ALMA Large Program to INvestigate C+ at Early times (ALPINE), a multiwavelength survey that examined galaxies that were around when the Universe was less than 1.5 billion years old. With funding provided by NASA and the European Southern Observatory (ESO), the ALPINE collaboration analyzed this data and learned some interesting things about the early evolution of galaxies.

March 30, 2020March 30, 2020 by Matt Williams

How were Supermassive Black Holes Already Forming and Releasing Powerful Jets Shortly After the Big Bang?

A supermassive black hole has been found in an unusual spot: an isolated region of space where only small, dim galaxies reside. Image credit: NASA/JPL-Caltech — A team of astronomers from South Africa have noticed a series of supermassive black holes in distant galaxies that are all spinning in the same direction. Credit: NASA/JPL-Caltech

In the past few decades, astronomers have been able to look farther into the Universe (and also back in time), almost to the very beginnings of the Universe. In so doing, they’ve learned a great deal about some of the earliest galaxies in the Universe and their subsequent evolution. However, there are still some things that are still off-limits, like when galaxies with supermassive black holes (SMBHs) and massive jets first appeared.

According to recent studies from the International School for Advanced Studies (SISSA) and a team of astronomers from Japan and Taiwan provide new insight on how supermassive black holes began forming just 800 million years after the Big Bang, and relativistic jets less than 2 billion years after. These results are part of a growing case that shows how massive objects in our Universe formed sooner than we thought.

January 7, 2020January 7, 2020 by Matt Williams

Astronomers See the Farthest Galaxy Group Ever Found, When the Universe was Only 5% of its Current Age

Inset: This illustration of the EGS77 galaxy group shows the galaxies surrounded by overlapping bubbles of ionized hydrogen. By transforming light-quenching hydrogen atoms to ionized gas, ultraviolet starlight is thought to have formed such bubbles throughout the early universe, gradually transitioning it from opaque to completely transparent. Background: This composite of archival Hubble Space Telescope visible and near-infrared images includes the three galaxies of EGS77 (green circles). Credits: NASA/ESA/V. Tilvi (ASU)

By looking deeper into space (and farther back in time), astronomers and cosmologists continue to push the boundaries of what is known about the Universe. Thanks to improvements in instrumentation and observation techniques, we are now at the point where astronomers are able to observe some of the earliest galaxies in the Universe – which in turn is providing vital clues about how our Universe evolved.

Using data obtained by the Kitt Peak National Observatory, a team of astronomers with the Cosmic Deep And Wide Narrowband (Cosmic DAWN) Survey were able to observe the farthest galaxy group to date. Known as EGS77, this galaxy existed when the Universe was just 680 million years old (less than 5% of the age of the Universe). Analysis of this galaxy is already revealing things about the period that followed shortly after the Big Bang.

November 5, 2019November 5, 2019 by Matt Williams

The First Stars Formed Very Quickly

Credit: Max Planck Institute for Astronomy

Ever since astronomers realized that the Universe is in a constant state of expansion and that a massive explosion likely started it all 13.8 billion years ago (the Big Bang), there have been unresolved questions about when and how the first stars formed. Based on data gathered by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) and similar missions, this is believed to have happened about 100 million years after the Big Bang.

Much of the details of how this complex process worked have remained a mystery. However, new evidence gathered by a team led by researchers from the Max Planck Institute for Astronomy indicates that the first stars must have formed rather quickly. Using data from the Magellan Telescopes at Las Campanas Observatory, the team observed a cloud of gas where star formation was taking place just 850 million years after the Big Bang.