Dark Energy Archives

January 26, 2022January 31, 2022 by Matt Williams

Finally, an Explanation for the Cold Spot in the Cosmic Microwave Background

Map of the cosmic microwave background (CMB) sky produced by the Planck satellite. The Cold Spot is shown in the inset, with coordinates and the temperature difference in the scale at the bottom. Credit: ESA/Durham University.

According to our current Cosmological models, the Universe began with a Big Bang roughly 13.8 billion years ago. During the earliest periods, the Universe was permeated by an opaque cloud of hot plasma, preventing atoms from forming. About 380,000 years later, the Universe began to cool and much of the energy generated by the Big Bang converted into light. This afterglow is now visible to astronomers as the Cosmic Microwave Background (CMB), first observed during the 1960s.

One peculiar characteristic about the CMB that attracted a lot of attention was the tiny fluctuations in temperature, which could provide information about the early Universe. In particular, there is a rather large spot in the CMB that is cooler than the surrounding afterglow, known as the CMB Cold Spot. After decades of studying the CMB’s temperature fluctuations, a team of scientists recently confirmed the existence of the largest cold spots in the CMB afterglow – the Eridanus Supervoid – might be the explanation for the CMB Cold Spot that astronomers have been looking for!

September 22, 2021September 25, 2021 by Matt Williams

A Particle Physics Experiment Might Have Directly Observed Dark Energy

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

About 25 years ago, astrophysicists noticed something very interesting about the Universe. The fact that it was in a state of expansion had been known since the 1920s, thanks to the observation of Edwin Hubble. But thanks to the observations astronomers were making with the space observatory that bore his name (the Hubble Space Telescope), they began to notice how the rate of cosmic expansion was getting faster!

This has led to the theory that the Universe is filled with an invisible and mysterious force, known as Dark Energy (DE). Decades after it was proposed, scientists are still trying to pin down this elusive force that makes up about 70% of the energy budget of the Universe. According to a recent study by an international team of researchers, the XENON1T experiment may have already detected this elusive force, opening new possibilities for future DE research.

June 21, 2021June 21, 2021 by Andy Tomaswick

Astronomers saw the Same Supernova Three Times Thanks to Gravitational Lensing. And in Twenty Years They Think They’ll see it one More Time

It is hard for humans to wrap their heads around the fact that there are galaxies so far away that the light coming from them can be warped in a way that they actually experience a type of time delay. But that is exactly what is happening with extreme forms of gravitational lensing, such as those that give us the beautiful images of Einstein rings. In fact, the time dilation around some of these galaxies can be so extreme that the light from a single event, such as a supernova, can actually show up on Earth at dramatically different times. That is exactly what a team led by Dr. Steven Rodney at the University of South Carolina and Dr. Gabriel Brammer of the University of Copenhagen has found. Except three copies of this supernova have already appeared – and the team thinks it will show up again one more time, 20 years from now.

May 30, 2021May 30, 2021 by Andy Tomaswick

Dark Energy Survey is out. 29 Papers Covering 226 Million Galaxies Across 7 Billion Light-Years of Space

Cosmology is now stranger to large scale surveys. The discipline prides itself on data collection, and when the data it is collecting is about galaxies that are billions of years old its easy to see why more data would be better. Now, with a flurry of 29 new papers, the partial results from the largest cosmological survey ever – the Dark Energy Survey (DES) – have been released. And it largely confirms what we already knew.

November 28, 2020November 29, 2020 by Matthew Cimone

One of These Pictures Is the Brain, the Other is the Universe. Can You Tell Which is Which?

Left: section of cerebellum, with magnification factor 40x, obtained with electron microscopy (Dr. E. Zunarelli, University Hospital of Modena); right: section of a cosmological simulation, with an extension of 300 million light-years on each side (Vazza et al. 2019 A&A).

“Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light years and in the passage of ages, when we grasp the intricacy, beauty and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual.” – Carl Sagan “The Demon-Haunted World.”

Learning about the Universe, I’ve felt spiritual moments, as Sagan describes them, as I better understand my connection to the wider everything. Like when I first learned that I was literally made of the ashes of the stars – the atoms in my body spread into the eternal ether by supernovae. Another spiritual moment was seeing this image for the first time:

Hippocampal mouse neuron studded with synaptic connections (yellow), courtesy Lisa Boulanger, from https://www.eurekalert.org/multimedia/pub/81261.php. The green central cell body is ? 10µm in diameter. B. Cosmic web (Springel et al., 2005). Scale bar = 31.25 Mpc/h, or 1.4 × 1024 m. Juxtaposition inspired by Lima (2009).

July 27, 2020July 27, 2020 by Matthew Cimone

Take a Flight Through the Most Detailed 3D Map of the Universe Ever Made

The most detailed map of the universe ever made

Once I accidentally took a photo of one of the most important stars in the Universe…

Andromeda Galaxy imaged at the SFU Trotter Observatory processed by Matthew Cimone

That star highlighted in the photo is called M31_V1 and resides in the Andromeda Galaxy. The Andromeda – AKA M31- is the closest galaxy to our own Milky Way. But before it was known as a galaxy, it was called the Andromeda Nebula. Before this particular star in Andromeda was studied by Edwin Hubble, namesake of the Hubble Space Telescope, we didn’t actually know if other galaxies even existed. Think about that! As recently as a hundred years ago, we thought the Milky Way might be the ENTIRE Universe. Even then…that’s pretty big. The Milky Way is on the order of 150,000 light years across. A light year is about 10 TRILLION kilometers so even at the speed of light it would take nearly the same length of time to cross the Milky Way as humans have existed on planet Earth. M31_V1 changed all that.

June 6, 2020June 6, 2020 by Evan Gough

A New Telescope is Ready to Start Searching for Answers to Explain Dark Energy

Back in 2015, construction began on a new telescope called the Dark Energy Spectroscopic Instrument (DESI). Later this year, it will begin its five-year mission. Its goal? To create a 3D map of the Universe with unprecedented detail, showing the distribution of matter.

That detailed map will allow astronomers to investigate important aspects of cosmology, including dark energy and its role in the expansion of the Universe.

March 12, 2020March 12, 2020 by Nancy Atkinson

Over a Hundred New Large Objects Found in the Kuiper Belt

This is an artist's concept of a craggy piece of Solar System debris that belongs to a class of bodies called trans-Neptunian objects (TNOs).Credit: NASA, ESA, and G. Bacon (STScI)

Hey Pluto, Sedna, Haumea, Makemake Et al.: You’ve got company!

While searching for distant galaxies and supernovae, the Dark Energy Survey’s powerful 570-megapixel digital camera spotted a few other moving “dots” in its field of view. Turns out, the DES has found more than 100 previously unknown trans-Neptunian objects (TNOs), minor planets located in Kuiper Belt of our Solar System.

A new paper describes how the researchers connected the moving dots to find the new TNOs, and also says this new approach could help look for the hypothetical Planet Nine and other undiscovered worlds.

Guess you never know what you’ll find once you start looking!

January 8, 2020January 8, 2020 by Brian Koberlein

New Research Casts A Shadow On The Existence Of Dark Energy

The cosmic distance ladder for measuring galactic distances. Credit: NASA,ESA, A. Feild (STScI), and A. Riess (STScI/JHU)

The universe is expanding. When we look in all directions, we see distant galaxies speeding away from us, their light redshifted due to cosmic expansion. This has been known since 1929 when Edwin Hubble calcuated the relation between a galaxy’s distance and its redshift. Then in the late 1990s, two studies of distant supernovae found that the expansion of the universe is accelerating. Something, some dark energy, must be driving cosmic expansion.

October 30, 2019October 30, 2019 by Evan Gough

New Telescope Instrument Will Watch the Sky with 5,000 Eyes

DESI's 5000 spectroscopic "eyes" can cover an area of sky about 38 times larger than that of the full moon, as seen in this overlay of DESI's focal plane on the night sky (top). Each one of these robotically controlled eyes can fix a fiber-optic cable on a single object to gather its light. Credit: DESI Collaboration

Dark Energy is the mysterious force driving the expansion of the Universe. We don’t know what dark energy is, even though it makes up about 68% of the Universe. And the expansion is accelerating, which only adds to the mystery.

A new instrument called the Dark Energy Spectroscopic Instrument (DESI) will study dark energy. It’s doing so with 5,000 new robotic “eyes.”