A SpaceX Falcon 9 lifts off from Cape Canaveral in Florida carrying 60 Starlink satellites, January 6, 2020.Image: SpaceX
Organizers of an American Astronomical Society conference in Hawaii held a special session to discuss the ways in which satellite megaconstellations, such as the one currently being built by SpaceX, are poised to disrupt telescopic observations. The astronomers also proposed potential solutions to this emerging problem.
The special session, titled “Challenges to Astronomy from Satellites,” was held yesterday at the 235th Meeting of the American Astronomical Society (AAS) currently being held in Honolulu, Hawaii. The session, chaired by Connie Walker from the National Science Foundation’s Optical-Infrared Astronomy Research Laboratory in Tucson, Arizona, was prompted by recent developments relating to the construction of the SpaceX Starlink megaconstellation, but the point of the meeting was to discuss the prospect in general, as several other firms are planning to build substantial satellite constellations of their own.
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That Starlink was a focal point of the meeting barely registers as a surprise. SpaceX has now launched three batches of its small-sats, which places the total number at around 180. Each launch has been accompanied by a light show, in which an orderly procession of Starlink satellites have been seen zipping across the night sky. This train-like effect lasts for a week or more until the satellites disperse to their higher service orbits, but even then they are still visible to the naked eye. Perhaps unsurprisingly, Starlink trains have already disrupted astronomical observations.
That’s certainly one problem, but another has to do with the sheer volume of satellites expected to enter into orbit over the coming years. SpaceX ultimately wants its Starlink constellation to consist of tens of thousands of satellites, while other companies, such as OneWeb, Telsat, and Amazon, are hoping to build their own multi-satellite constellations. The private sector is set to increase the number of objects in space by an order of magnitude, and this unprecedented experiment—without any apparent thought to the consequences—could disrupt astronomical observations to an alarming degree.
Jonathan McDowell, an astronomer at Harvard-Smithsonian Center for Astrophysics and an expert on satellites, attended this special AAS session and talked to his peers about the subject. He also met with SpaceX reps.
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“I do believe SpaceX is making a good-faith effort to fix the problem,” McDowell told Gizmodo in an email. “I think they can get the satellites fainter than what the naked eye can see, which is a minimal thing to not spoil the night sky for non-astronomers.”
As for professional astronomers, he fears there will be times of the year when these satellites will pose “at minimum a big problem,” saying he worries there will be issues astronomers have not even thought of yet.
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During yesterday’s session, Patricia Cooper, the vice president of satellite government affairs for SpaceX, said the “level of brightness and visibility was a surprise to us,” reported SpaceNews.
This unexpected luminosity, said Cooper, is a consequence of the satellites having to be deposited in a low orbit as well as the way in which their large solar arrays are initially oriented. Once in their intended orbits, some 550 kilometers (342 miles) above Earth, their brightness is vastly diminished, but they can still be seen from the ground.
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SpaceX has responded to this problem. For the most recent deployment—in which SpaceX became the largest commercial satellite operator in the world—one Starlink satellite was treated with a special dark coating intended to diminish its reflectivity. We won’t know if this solution will work until February, when the satellites go into service.
In addition, the private space company is making the coordinates of each Starlink satellite available to astronomers, who can use this information when planning their observations, according to the Washington Post.
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“We don’t know yet if these mitigations are useful and effective,” said Cooper. “We tend to work very quickly. We tend to test, learn and iterate.”
The session also addressed megaconstellations in general, discussing the ways in which these satellite arrays could influence scientific observations, whether these satellites are used for telecommunications, as is the case for Starlink, or sweeping surveys of the Earth’s surface, such as the proposed ICEYE constellation, which would involve fleets of satellites equipped with synthetic-aperture radar (SAR).
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Speaking at the session, astronomer Patrick Seitzer from the University of Michigan warned of the deleterious effects, such as multiple streaks on images, ghost-like artifacts, the saturation of detectors with light, and interference with electronic devices, the BBC reported.
“Mega-constellations in Low Earth Orbit are coming and they are coming fast,” Seitzer was quoted as saying in the BBC. “The new satellites are brighter than 99% of objects in orbit,” adding that the initial batch of Starlink sats is “just the start.”
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Seitzer recommended that SpaceX make it so that its Starlink satellites are not visible to the naked eye even when in their service orbits and that the company work to reduce the brightness of these objects to prevent the over-saturation of large professional telescopes, the BCC reported. Upsettingly, he said the Vera C. Rubin Observatory, previously known as the Large Synoptic Survey Telescope, will be badly affected by megaconstellations, as this observatory, with its highly sensitive equipment, will map the entire sky once every three days.
Another problem mentioned at the conference is the threat of excessive radio interference coming from some of these satellites, such as the aforementioned ICEYE. Speaking to reporters at the conference, Harvey Liszt from the National Radio Astronomy Observatory (NRAO), said if SAR is pointed at a radio telescope that’s looking directly back at it, SAR “will burn out the radio astronomy receiver,” reported the BBC.
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Hopefully these discussions will further compel the private sector to adopt sensible practices prior to lobbing their products into space. It’s deeply disappointing that we’re having these conversations so late into the game. Being able to predict that tens of thousands—or possibly even hundreds of thousands—of satellites in low Earth orbit will affect our view of the cosmos isn’t exactly rocket science.
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.
