Radar tweaks driving balloon finds, US officials say

The U.S. Air Force is seeing more “airborne objects” across North America’s skies after recalibrating radars patrolling U.S. airspace, defense officials said Monday after three such objects were shot down over the weekend.
The intensified effort to scan the skies follows the U.S. Air Force’s downing of an alleged Chinese spy balloon off South Carolina’s coast on Feb. 4. Beijing has denied any knowledge of the three new objects, instead accusing the United States of itself flying balloons over Chinese airspace.
The three unidentified objects shot down over the U.S. and Canada–one each on Friday, Saturday and Sunday–were not assessed to be military threats, but posed potential flight hazards, authorities said.
The initial spy balloon episode “was something that got all of our attention” and had led to “better scrutiny of our airspace” in the days since, said Gen. Charles Q. Brown, the chief of staff of the Air Force.
He said that could be a reason for the surge of sightings of the new “objects,” about which U.S. officials have remained tight-lipped. 
“Also, the adjusting of the radar sensitivities, which means we"re seeing more things than we would normally see,” Brown said. 
“But we don"t fully appreciate or understand exactly what we"re seeing,” he said the Brookings Institution Monday.
Brown’s remark followed similar comments from Melissa Dalton, assistant U.S. secretary of defense for homeland defense and hemispheric affairs, at a news conference on Sunday evening.
Dalton said the new objects were different from the downed Chinese balloon “in that we knew precisely what it was.” But she said that the three subsequent objects had flown nearby key defense sites and were at an altitude dangerous for civilian aircraft.
“We have been more closely scrutinizing our airspace at these altitudes, including enhancing our radar, which may at least partly explain the increase in objects that we’ve detected over the past week,” Dalton said, noting they posed no “kinetic military threat.”
Alleged China link
Asked whether the number of objects now being found was unusual or just a reflection of increased scrutiny, John Kirby, spokesman for President Joe Biden’s National Security Council, said it was safe to assume it was due to the increased sensitivity of the radar filters.
“One of the reasons that we think we"re seeing more, is because we"re looking for more,” Kirby told reporters at the White House.
“They have modified the filters and the gains, as we call it, of the radar capabilities to look more discretely at high-altitude, small-radar cross-section and low-speed objects,” he explained. “If you set the parameters in such a way to look for a certain something, it"s more likely that you"re going to find a certain something.”
U.S. officials say they cannot rule out any source of the new “unidentified aerial objects” before further investigations, and have so far stopped short of blaming Beijing for the latest finds. But Kirby did say U.S. intelligence indicated an ongoing program of balloon surveillance linked to the People’s Republic of China.
“We were able to determine that China has a high-altitude balloon program for intelligence collection that"s connected to the People"s Liberation Army. It was operating during the previous administration, but they did not detect it. We detected it,” he said.
“We know that these PRC surveillance balloons have crossed over dozens of countries on multiple continents around the world, including some of our closest allies and partners.”
White House press secretary Karine Jean-Pierre said at the same press conference that one source of the unidentified objects could be definitively ruled out. “There is no – again, no indication – of aliens or extraterrestrial activity with these recent takedowns,” she said. “I loved E.T., the movie, but I’m just going to leave it there.”
China"s counterclaim
Beijing has hit back at claims it has been caught spying on U.S. military sites. It attacked the Feb. 4 shooting down of its balloon, which it says was a civilian meteorological aircraft, as an act of aggression that went against the spirit of international law.
On Monday, China’s Foreign Ministry spokesman, Wang Wenbin, said Beijing had in fact identified 10 U.S. balloons in its own airspace over the last year, and that such transgressions were “common.”
“The United States should first reflect on itself and change course, rather than slander, discredit or incite confrontation,” he said.
Appearing on MSNBC’s “Morning Joe,” Kirby denied the claims.
“Not true. Not doing it. Just absolutely not true,” Kirby said when asked about the claims. “We are not flying balloons over China.”
He said talks with Beijing over the balloon fracas were ongoing. 
Bloomberg reported on Monday that U.S. Secretary of State Antony Blinken was considering a meeting with his Chinese counterpart, Wang Yi, at the Munich Security Conference later this week.
“It"s not like all communications between us and the PRC have shut down,” Kirby said, amid reports Chinese officials rejected phone calls over the balloon issue. “That"s unfortunate, but we do have the ability to communicate directly with Chinese leaders, and we have, in private settings, about our concerns over the spy balloon.”


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