Astronomers using the Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, have detected multiple rock-forming elements in the atmosphere of a Jupiter-sized exoplanet, WASP-76b. The planet is so perilously close to its host star that rock-forming elements — such as magnesium, calcium, and nickel — become vaporized and dispersed throughout its scorching atmosphere. This intriguing chemical profile provides new insights into the formation of planetary systems, including our own.
WASP-76b is a strange world. Located 634 light-years from Earth in the direction of the constellation of Pisces, the Jupiter-like exoplanet orbits its host star at an exceptionally close distance — approximately 12 times closer than Mercury is to the Sun — which heats its atmosphere to a searing 2000°C. Such extreme temperatures have “puffed up” the planet, increasing its volume to nearly six times that of Jupiter.
At such extreme temperatures, mineral- and rock-forming elements, which would otherwise remain hidden in the atmosphere of a colder gas-giant planet, can reveal themselves.
Using the Gemini North telescope, one half of the International Gemini Observatory operated by NSF’s NOIRLab, an international team of astronomers has detected 11 of these rock-forming elements in the atmosphere of WASP-76b. The presence and relative amounts of these elements can provide key insights into exactly how giant gas planets form — something that remains uncertain even in our own Solar System. The results are published in the journal Nature.
Since its discovery in 2013 during the Wide Angle Search for Planets (WASP) program, many astronomers have studied the enigmatic WASP-76b. These studies have led to the identification of various elements present in the hot exoplanet’s atmosphere. Notably, in a study published in March 2020, a team concluded that there could be iron rain on the planet.
Aware of these existing studies, Stefan Pelletier, a PhD student with the Trottier Institute for Research on Exoplanets at the Université de Montréal and lead author on the paper, was inspired to explore the mysteries of this strange exoplanet and the chemistry of its searing atmosphere.
In 2020 and 2021, using Gemini North’s MAROON-X (a new instrument specially designed to detect and study exoplanets), Pelletier and his team observed the planet as it passed in front of its host star on three separate occasions. These new observations uncovered a number of rock-forming elements in the atmosphere of WASP-76b, including sodium, potassium, lithium, nickel, manganese, chromium, magnesium, vanadium, barium, calcium, and, as previously detected, iron.
Due to the extreme temperatures of WASP-76b’s atmosphere, the elements detected by the researchers, which would normally form rocks here on Earth, are instead vaporized and thus present in the atmosphere in their gaseous forms. While these elements contribute to the composition of gas giants in our Solar System, those planets are too cold for the elements to vaporize into the atmosphere making them virtually undetectable.
“Truly rare are the times when an exoplanet hundreds of light-years away can teach us something that would otherwise likely be impossible to know about our own Solar System,” said Pelletier. “That is the case with this study.”
The abundance of many of these elements closely match the abundances found in both our Sun and the exoplanet’s host star. This may be no coincidence and provides additional evidence that gas-giant planets, like Jupiter and Saturn, form in a manner more akin to star formation — coalescing out of the gas and dust of a protoplanetary disk — rather than the gradual accretion and collision of dust, rocks, and planetesimals, which go on to form rocky planets, like Mercury, Venus, and Earth.
Another notable result of the study is the first-ever unambiguous detection of vanadium oxide on an exoplanet. “This molecule is of high interest to astronomers because it can have a great impact on the atmospheric structure of hot giant planets,” says Pelletier. “This molecule plays a similar role to ozone being extremely efficient at heating Earth’s upper atmosphere.”
Pelletier and his team are motivated to learn more about WASP-76b and other ultra-hot planets. They also hope other researchers will leverage what they learned from this giant exoplanet and apply it to better our understanding of our own Solar System planets and how they came to be.
“Available to astronomers across the globe, the International Gemini Observatory continues to deliver new insights that push our understanding of the physical and chemical structure of other worlds. Through such observational programs we are developing a clearer picture of the wider universe and our own place in it,” said NSF Gemini Observatory program director Martin Still.
“Generations of researchers have used Jupiter, Saturn, Uranus, and Neptune measured abundances for hydrogen and helium to benchmark formation theories of gaseous planets,” says Université de Montréal professor Björn Benneke, a co-author on the study. “Likewise, the measurements of heavier elements such as calcium or magnesium on WASP-76b will help further understanding the formation of gaseous planets.”
Journal Reference
Pelletier, S., Benneke, B., Prinoth, B., Kasper, D., Seifahrt, A., Bean, J. L., Debras, F., Klein, B., Bazinet, L., Hoeijmakers, H. J., Kesseli, A. Y., Lim, O., Carmona, A., Pino, L., Hood, T., & Stürmer, J. (2023). Vanadium oxide and a sharp onset of cold-trapping on a giant exoplanet. Nature, 1-4. DOI: 10.1038/s41586-023-06134-0
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.
