Dark matter has never been seen, but scientists think it could help explain the mysteries of the universe. And one Alberta researcher is trying to build a machine to detect it.
Dark matter is a key ingredient of our universe, making up almost one-third of it, according to NASA.
“Dark matter interacts gravitationally, we can see the effects of dark matter on galaxies,” said Marie-Cécile Piro, associate physics professor at the University of Alberta.
“It’s very, very abundant.”
Our universe consists of two other components: dark energy — which is believed to drive the expansion of the universe — and ordinary matter, such as stars, planets, trees and animals, consisting of protons, neutrons and electrons.
Over its lifetime, Euclid, what the European Space Agency has dubbed a ‘dark universe detective,’ will image billions of galaxies, revealing the unseen influence that dark matter and dark energy have on them. (ESA/Euclid/Euclid Consortium/NASA; Image processing by J.-C. Cuillandre [CEA Paris-Saclay], G. Anselmi)
Dark matter is invisible. It does not absorb, reflect or emit light. Some scientists, according to NASA, think dark matter exists in a vast, web-like structure that holds the visible universe together, like scaffolding at a construction site.
“We don’t know really what it is, but it could be a particle that we can detect on Earth,” Piro said.
It’s thought, dark matter is five times more abundant than ordinary matter.
Who coined ‘dark matter’?
Swiss astronomer Fritz Zwicky was trying to measure the visible mass of a cluster of galaxies in 1933, but found the galaxies were too small to prevent them from escaping the gravitational pull of the entire cluster. Zwicky concluded there must be something — like dark matter – keeping the galaxies glued together.
Since then, other scientists have used dark matter to help explain what keeps galaxies from flying apart.
Yet, it’s still unknown what dark matter is made of.
The Bubble chamber detector at the SNOLAB underground laboratory in Sudbury Canada for the PICO dark matter experiment in 2018. (Submitted by Marie-Cécile Piro)
To help solve the mystery, Piro is trying to build a detector to find dark matter. She was recently awarded a Dorothy Killam Fellowship, worth $160,000, for her project.
However, it’s not an easy task.
For one, the detector would have to be extremely sensitive.
“If we take one grain of salt and let it fall from one millimetre above the floor, the force that the grain of salt will touch the floor divided by a 100 billion, is the kind of detection event we would need to detect,” said Piro.
She aims to have the detector built by the year’s end, using a bubble chamber to track the movement of particles.
Radio Active11:22Shining a light onto the dark
We talk to University of Alberta researcher Marie-Cécile Piro about her work to detect the undetectable — known as dark matter.
If successful, it could help unlock the secret to black holes, dark energy or even how the universe was born.
What if there is no dark matter?
Not all scientists agree on dark matter.
A study, published just last month from the University of Ottawa, challenges the current model of the universe, by suggesting dark matter does not exist. The study, Testing CCC+TL Cosmology with Observed Baryon Acoustic Oscillation Features, was published in the peer-reviewed Astrophysical Journal.
“Dark matter has explained so many things in the universe that people are very much attached to. But lately they are finding lot of things that cannot be explained by it,” said Rajendra Gupta, physics professor and the study’s author.
A cosmic homicide in action, with a wayward star being shredded by the intense gravitational pull of a black hole that contains tens of thousands of solar masses in an artist’s impression obtained by Reuters April 2, 2020. (D. Player/NASA/ESA/Reuters)
NASA’s James Webb Space Telescope, said Gupta, has poked holes in dark matter theory, by capturing images of galaxies that appear to have grown too big too fast, going against the current model of the universe.
But the galaxies’ gigantic sizes would make sense, if our universe is older, he said.
“That means now we have a lot more time to create these galaxies with or without dark matter than was possible with the original model.”
“There are so many options to the argument over dark matter.”
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
