Unsettled science

A new study published last week by a Nobel Prize–winning astrophysicist could shake up what scientists thought they knew about the origins of the universe. New research from Adam Riess of Johns Hopkins University strengthens his previous claims that the universe could be expanding faster than it used to and be much younger than mainstream scientists believed.

Riess’ research centers on the Hubble constant, which scientists use to calculate how fast the universe is expanding. In 2013, scientists used information about background radiation, believed by scientists to be the cosmic leftovers of the Big Bang, gathered from the European Planck satellite. That study set the expansion rate of the universe at about 67 kilometers per second for two astronomical bodies separated by 3.26 million light-years. The calculations led to an estimated universe age of 13.8 billion years, based on the assumptions of the Big Bang theory.

But Riess’ new study, building on smaller-scale research he published last year, came up with far different results. His method, which involved calculating the distance of regularly pulsing stars and comparing them to a kind of supernovae, is much more direct than the old calculations. Based on numbers from NASA’s Hubble Space Telescope, Riess thinks the expansion rate is 74 kilometers per second—about 9 percent faster than the old rate. If he’s correct, the universe would only be between 12.5 and 13 billion years old.

While the difference between 13.8 billion and 13 billion may not seem significant, it’s shaking up the astronomy community and unsettling previously established facts and theories.

“It’s looking more and more like we’re going to need something new to explain this,” said Riess, who won the 2011 Nobel Prize in physics.

No one has been able to find a flaw in either set of calculations that would explain why they get different results. To solve the discrepancy, scientists are considering everything from trying to find a new particle of matter to postulating something new in the universe (like they did in the past with dark energy and matter)—or even adjusting Albert Einstein’s theory of relativity. NASA astrophysicist John Mather, another Nobel Prize winner, said the problem leaves scientists with two options: “One, we’re making mistakes we can’t find yet. Two, nature has something we can’t find yet.”

Astronomers at the University of Chicago are looking at different stars than Riess used in his research to come up with their own expansion rate. Their research hasn’t been published, but a scientist leading the report said they found a Hubble constant between the other two numbers. The dilemma of the Hubble constant reminds us that that even the most solid-seeming scientific theories are open to questions, and we have much to discover still about God’s creation.

A gold foil cross from an Anglo-Saxon burial site in the village of Prittlewell on display in Southend, England Associated Press/Photo by James Brooks

Christian burial

Last week, dozens of artifacts went on display near the burial site of potentially one of the earliest Anglo-Saxon converts to Christianity. Road workers in 2003 found the underground burial chamber between a road and a railway line in Prittlewell, England, and archaeologists have been studying the contents ever since. They now believe the 1,400-year-old tomb is the most important Anglo-Saxon burial discovery in recent times. Artifacts include gold foil crosses on the head of the coffin, a gold belt buckle, the remnants of a lyre, glassware, and a Middle Eastern water jug.

No one knows who was buried in the tomb, but the luxurious nature of the contents suggests royalty. Locals dubbed the buried person the “Prittlewell Prince.” Sophie Jackson, director of research and engagement at the Museum of London Archaeology, said the significance of the find is “our equivalent of Tutankhamun’s tomb,” the burial site of Egypt’s famous King Tut.

Jackson said if she had to guess, the room is probably the tomb of Seaxa, the brother of King Saebert, who was the first Anglo-Saxon king to become a Christian. “[The Anglo-Saxons] would have been just on the transition between having pagan burials with all your gear, but also having these crosses,” she said. —Samantha Gobba

A gold foil cross from an Anglo-Saxon burial site in the village of Prittlewell on display in Southend, England Associated Press/Photo by James Brooks

Overbred

Tampering with creation by way of artificial selection may lead to useful results, but in some cases it can also have dangerous side effects. In the case of horse breeding, selecting for traits like speed has led to low genetic diversity, according to a new genome study. Molecular archaeologist Ludovic Orlando, author of the study and a scientist at the French National Center for Scientific Research, said domesticated horses now have an all-time low level of diversity in their Y chromosomes.

Of all domestic thoroughbreds, about 95 percent have Y chromosomes that trace their lineage from Darley Arabian, a stallion born in 1700. Low levels of genetic diversity often lead to genetic defects. For horses, it has meant diseases like night blindness and myopathy, or muscle disease. —S.G.

Adaptive plants

God’s design is evident in how the plant Brassica rapa detects changes to its environment and adapts to them. A recent study of the plant—whose subspecies include turnips, bok choy, and field mustard—found that specimens free from attacks by herbivores produced larger, sweeter-smelling flowers, which are more attractive to pollinators, according to researchers at the University of Zurich. Conversely, plants attacked by caterpillars put their resources into defensive toxic metabolites and grew smaller, less sweet-smelling flowers. —S.G.