NEW YORK (AP) — Scientists have detected cosmic waves that sound like birds chirping in an unexpected place.
These bursts of plasma, called chorus waves, ripple at the same frequency as human hearing. When converted to audio signals, their sharp notes mimic high-pitched bird calls.
Researchers have captured such sounds in space before, but now they have sensed the chirping waves from much farther away: over 62,000 miles (100,000 kilometers) from Earth, where they've never been measured before.
“That opens up a lot of new questions about the physics that could be possible in this area,” said Allison Jaynes, a space physicist at the University of Iowa who was not involved with the work.
Scientists still aren’t sure how the perturbations happen, but they think Earth’s magnetic field may have something to do with it.
The chorus has been picked up on radio antennas for decades, including receivers at an Antarctica research station in the 1960s. And twin spacecraft — NASA's Van Allen Probes — heard the chirps from Earth's radiation belts at a closer distance than the newest detection.
The latest notes were picked up by NASA's Magnetospheric Multiscale satellites, launched in 2015 to explore the Earth and sun's magnetic fields. The new research was published Wednesday in the journal Nature.
Chorus waves have also been spotted near other planets including Jupiter and Saturn. They can even produce high-energy electrons capable of scrambling satellite communications.
“They are one of the strongest and most significant waves in space,” said study author Chengming Liu from Beihang University in an email.
The newfound chorus waves were detected in a region where Earth's magnetic field is stretched out, which scientists didn't expect. That raises fresh questions about how these chirping waves form.
“It's very captivating, very compelling,” Jaynes said. “We definitely need to find more of these events.”
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.
NASA’s four Magnetospheric Multiscale, or MMS, satellites at the Astrotech Space Operations facility in Titusville, Florida, March 2015. (NASA via AP)
CAIRO (AP) — Hamas said Saturday it would only release an American-Israeli and the bodies of four other hostages if Israel implements the existing ceasefire agreement in the Gaza Strip, calling it an “exceptional deal” aimed at getting the truce back on track.
A senior Hamas official said long-delayed talks over the ceasefire's second phase would need to begin the day of the release and last no longer than 50 days. Israel would also need to stop barring the entry of humanitarian aid and withdraw from a strategic corridor along Gaza's border with Egypt.
Hamas would also demand the release of more Palestinian prisoners in exchange for hostages, said the official, who spoke on condition of anonymity to discuss the closed-door talks.
Edan Alexander, 21, who grew up in Tenafly, New Jersey, was abducted from his military base during Hamas’ Oct. 7, 2023, attack that ignited the war, and is the last living American citizen held in Gaza.
A Palestinian official meanwhile said that Israel's ban on the entry of fuel would prevent the operation of dozens of wells across the southern city of Rafah, reducing the supply of drinking water.
There was no immediate comment from Israel, where government offices were closed for the weekly Sabbath. Israeli Prime Minister Benjamin Netanyahu’s office on Friday accused Hamas of “manipulation and psychological warfare” when the offer was initially made, before Hamas spelled out the conditions.
The United States said it presented on Wednesday a proposal to extend the ceasefire a few more weeks as the sides negotiate a permanent truce. It said Hamas was claiming flexibility in public while privately making “entirely impractical” demands.
Negotiations continued in Egypt after senior Hamas leader Khalil al-Hayya arrived in Cairo on Friday. Egypt and Qatar served as key mediators with Hamas in reaching the ceasefire and have continued to host talks aimed at getting it back on track.
There was no immediate comment from the mediators.
Under the ceasefire agreement reached in January, Israel and Hamas were to begin negotiations over a second phase — in which Hamas would release all the remaining hostages in exchange for a lasting truce — in early February, but so far only preparatory talks have been held.
After the first phase ended at the beginning of this month, Israel said it had agreed to a new U.S. proposal in which Hamas would release half the remaining hostages in return for a vague commitment to negotiate a lasting ceasefire. Hamas rejected that offer, accusing Israel of backtracking on the signed agreement and trying to sabotage the truce.
Israel has barred the delivery of food, fuel and other supplies to Gaza's roughly 2 million Palestinians, and cut electricity to the territory, to pressure Hamas to accept the new proposal.
The city of Rafah, on the Gaza-Egypt border, said it could no longer provide fuel needed to pump water from dozens of wells across the city.
Ahmed al-Sufi, head of the Rafah municipality, said fuel shortages caused by the Israeli siege have forced the municipality to “suspend essential services, threatening the lives of thousands and exacerbating the health and environmental crisis.”
The first phase of the truce, which took hold on Jan. 19, saw the release of 25 Israeli hostages and the bodies of eight more in exchange for nearly 2,000 Palestinian prisoners. Israeli forces pulled back to a buffer zone along Gaza's border and allowed a surge of humanitarian aid.
An Israeli official said last month that Israel will not withdraw from the so-called Philadelphi corridor, along the Gaza-Egypt border, as called for in the ceasefire agreement. They have cited the need to combat weapons smuggling.
The war began when Hamas-led militants stormed into southern Israel on Oct. 7, 2023, killing some 1,200 people, mostly civilians, and taking 251 hostage. The group is still holding 59 hostages, 24 of whom are believed to be alive, after most of the rest were freed in ceasefire agreements.
Israel's military offensive has killed over 48,000 Palestinians, mostly women and children, according to Gaza's Health Ministry, which does not say how many of the dead were combatants. Israel says it has killed around 20,000 militants, without providing evidence.
The war has destroyed vast areas of Gaza, displaced most of the population and left nearly everyone dependent on international aid to survive.
Follow AP’s war coverage at https://apnews.com/hub/israel-hamas-war
Displaced Palestinians burn waste in central Gaza Strip on Friday, March 14, 2025. (AP Photo/Jehad Alshrafi)
Palestinians walk amid the rubble of destroyed homes and buildings in Jabaliya, northern Gaza Strip on Friday, March 14, 2025. (AP Photo/Jehad Alshrafi)
Palestinians walk amid the rubble of destroyed homes and buildings in Jabaliya, northern Gaza Strip on Friday, March 14, 2025. (AP Photo/Jehad Alshrafi)
Palestinians walk amid the rubble of destroyed homes and buildings in Jabaliya, northern Gaza Strip on Friday, March 14, 2025. (AP Photo/Jehad Alshrafi)
