Skip to main content

Astronomers create most accurate map yet of all the matter in the universe

Of all the questions facing astronomers today, some of the biggest unknowns are about the stuff that makes up most of the universe. We know that the ordinary matter we see all around us makes up just 5% of all that exists, while the rest is made up of dark matter and dark energy. But because dark matter doesn’t interact with light, it is extremely hard to study — we have to infer its existence and position from looking at the way it interacts with the ordinary matter around it.

The Blanco Telescope dome at the Cerro Tololo Inter-American Observatory in Chile, where the Dark Energy Camera used for the recently completed Dark Energy Survey was housed.
The Victor M. Blanco Telescope dome at the Cerro Tololo Inter-American Observatory in Chile, where the Dark Energy Camera used for the recently completed Dark Energy Survey is housed. Reidar Hahn, Fermilab

Recent research is helping in this task by producing the most accurate map to date of how both matter and dark matter are spread across the universe. Astronomers collected information from two different telescopes, the Dark Energy Survey telescope and the South Pole Telescope, to make their map as precise as possible.

Recommended Videos

For both telescope data sets, the researchers used the phenomenon of gravitational lensing — in which a massive body like a star, galaxy, or galaxy cluster warps spacetime and acts like a magnifying glass — to detect both regular matter and dark matter.

By comparing maps of the sky from the Dark Energy Survey telescope (at left) with data from the South Pole Telescope and the Planck satellite (at right), the team could infer how the matter is distributed.
By comparing maps of the sky from the Dark Energy Survey telescope ( from left) with data from the South Pole Telescope and the Planck satellite, the team could infer how the matter is distributed. Yuuki Omori

The results brought some surprises, like the fact that matter is less clumpy than would be expected based on current models of how the universe formed. It shows that the matter is more evenly spread out that predicted. If other surveys find similar results, this could indicate that there is something missing from current theories on how the universe formed in the period immediately following the Big Bang.

Please enable Javascript to view this content

“I think this exercise showed both the challenges and benefits of doing these kinds of analyses,” said one of the lead authors of the research, Chihway Chang of the University of Chicago, in a statement. “There’s a lot of new things you can do when you combine these different angles of looking at the universe.”

The research is published in three papers in the journal Physical Review D.

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
Astronomers spot an exoplanet creating spiral arms around its star
The Large Binocular Telescope in Arizona. The LBTI instrument combines infrared light from both 8.4-meter mirrors to image planets and disks around young and nearby stars.

When you imagine a galaxy like our Milky Way, you're probably picturing a swirl shape with arms reaching out from a central point. These spiral arms are a classic feature of many galaxies. Similar structures can be found around young stars which are surrounded by disks of matter from which planets form, called protoplanetary disks. Now, astronomers have discovered evidence that these structures could be created by recently formed exoplanets.

Astronomers used Large Binocular Telescope in Arizona to investigate a giant exoplanet named MWC 758c which seems to be forming the spiral arms around its host star. Located 500 light-years away, the star is just a few million years old, making it a baby in cosmic terms. "Our study puts forward a solid piece of evidence that these spiral arms are caused by giant planets," said lead researcher Kevin Wagner of the University of Arizona in a statement. "And with the new James Webb Space Telescope, we will be able to further test and support this idea by searching for more planets like MWC 758c."

Read more
Euclid mission launches to probe the mysteries of dark matter
This artist’s concept shows the ESA (European Space Agency) Euclid mission in space.

The European Space Agency (ESA) has successfully launched its Euclid space telescope to study the mysteries of dark matter and dark energy. The spacecraft launched from Cape Canaveral in Florida using a SpaceX Falcon 9 rocket, with liftoff at 11:12 a.m. ET (8:12 a.m. PT).

This artist’s concept shows the ESA (European Space Agency) Euclid mission in space. ESA, CC BY-SA 3.0 IGO

Read more
How to watch the Euclid dark matter telescope launch this Saturday
This artist impression shows Euclid leaving Earth and on its way to Sun-Earth Lagrange point L2. This equilibrium point of the Sun-Earth system is located 1.5 million kilometres from Earth in the opposite direction of the Sun. L2 revolves around the Sun along with Earth. During Euclid’s orbit at L2, Euclid’s sunshield always blocks the light from the Sun, Earth and Moon while pointing its telescope towards deep space, ensuring a high level of stability for its instruments.

The astronomy community is about to get a new instrument to probe the mysteries of dark matter, with the launch of the European Space Agency (ESA)'s Euclid telescope this Saturday. Euclid is a highly sophisticated space-based telescope that will observe huge swaths of the sky to create a 3D model of the universe to help elucidate some of the biggest questions in cosmology.

Euclid | Journey to darkness

Read more