Astronomers have made another stride forward in their quest to image the birth of a planet around another star directly.
For decades, scientists have been developing the basic ideas about how planets form around stars. First, a star forms from a collapsing cloud of gas and dust. The remaining material surrounding the star is spun into a disk by the star’s rotation, and parts of that disk clump together due to gravity. As these clumps gather more material to them, first planetesimals form, then protoplanets, and finally planets.
While this all makes sense, theoretically, these ideas still need to be verified by actual observations, and there are many details still missing from this model. Astronomers had to wait until 2018 for telescopes to improve to the point where they could start capturing images of protoplanetary disks. Until now, however, they still had not been able to focus in close enough to see an infant planet in the process of forming.
Over the past year, Anthony Boccaletti, from the Paris Observatory at France’s PSL University, led an international team in an attempt to do just that.
“Thousands of exoplanets have been identified so far, but little is known about how they form,” Boccaletti said in a European Southern Observatory (ESO) news release. “We need to observe very young systems to really capture the moment when planets form.”
Using the ESO’s Very Large Telescope (VLT), high up in the mountains of Northern Chile, Boccaletti and his team zoomed in on AB Aurigae, a young star in the constellation Auriga, located around 520 light-years away from Earth.
The ESO’s Very Large Telescope (VLT) beams a ‘guiding star’ laser up into the night sky, allowing its adaptive optics to take the clearest images of distant objects in space. Credit: ESO
Peering into the core of the AB Aurigae system, VLT captured the best images of the star’s planet-forming disk taken yet. Although they did not directly see a planet there, these images did capture the next-best thing.
AB Aurigae imaged by the ESO’s SPHERE instrument. Credit: ESO/Boccaletti et al.
What we see here is an image captured by VLT’s Spectro-Polarimetric High-contrast Exoplanet REsearch instrument, also known as SPHERE. To produce this view of the system, SPHERE relies on a particular property of light to become ‘polarized’ as it reflects off a surface. SPHERE can apply various filters to collect the polarized light reflecting off dust grains and other objects surrounding a star. By doing so, it filters out all the unpolarized light being emitted directly by the star.
Thus, while a view like this would typically be completely washed out by the light from the star, SPHERE gives astronomers a detailed look without that bright interference.
This VLT image for AB Aurigae reveals a bright ‘twist’ in the material around the star. Credit: ESO/Boccaletti et al./Scott Sutherland
By using SPHERE to observe AB Aurigae, Boccaletti and his team were able to resolve all the spirals of dense material (bright), and the darker gaps between those spirals.
In a particularly important find, though, they also spotted a bright ‘twist’ in the disk of material spiralling around the star, at roughly the same distance that Neptune orbits around the Sun. They identified this twist as the likely location of a planet in the process of forming.
As study co-author Emmanuel Di Folco of the Astrophysics Laboratory of Bordeaux (LAB) explained in an ESO press release, similar to a wave in the wake of a boat, this twist is a telltale sign that something big is moving through the gas and dust of this star’s protoplanetary disk.
A larger view of the ‘twist’ reveals the spiral arms in more detail. The researchers also note a potential second planet in the view. Credit: ESO/Boccaletti et al./Scott Sutherland
“The twist is expected from some theoretical models of planet formation,” co-author Anne Dutrey, also with the Astrophysics Laboratory of Bordeaux, said in the press release. “It corresponds to the connection of two spirals – one winding inwards of the planet’s orbit, the other expanding outwards – which join at the planet location. They allow gas and dust from the disc to accrete onto the forming planet and make it grow.”
In the study, published in the journal Astronomy & Astrophysics, the researchers note that a second planet may be indicated in this view of AB Aurigae. It shows up as more of a ‘point source’, however, rather than another twist. They give a rough estimate that if this were another planet forming, it would likely be around three times the mass of Jupiter. The baby planet inside the ‘twist’ could be significantly larger, they say, with estimates of anywhere from 4-13 times Jupiter’s mass!
Astronomers will likely have to wait until the ESO completes their Extremely Large Telescope (ELT) in 2025 to revisit AB Augirae for a more detailed look. This current discovery is still significant, however. Not only will teach astronomers more about how alien exoplanets form, but it will help them to find even more of these baby planets in the making.
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.
