Saskatchewan Premier Scott Moe, Chief Cadmus Delorme and Prime Minister Justin Trudeau walk though a field prior to a ceremony at the site of a former residential school where small flags which were placed, last month, in spots where ground-penetrating radar detected a potential 751 unmarked graves, in Cowessess First Nation, Saskatchewan, Canada July 6, 2021. Liam Richards/Pool via REUTERS

Prime Minister Justin Trudeau lays a teddy bear at a small flag in a field prior to a ceremony at the site of a former residential school where, last month, ground-penetrating radar detected a potential 751 unmarked graves, in Cowessess First Nation, Saskatchewan, Canada July 6, 2021. Liam Richards/Pool via REUTERS

Saskatchewan Premier Scott Moe lays a teddy bear at a small flag in a field prior to a ceremony at the site of a former residential school where, last month, ground-penetrating radar detected a potential 751 unmarked graves, in Cowessess First Nation, Saskatchewan, Canada July 6, 2021. Liam Richards/Pool via REUTERS

Prime Minister Justin Trudeau lays a teddy bear at a small flag in a field prior to a ceremony at the site of a former residential school where, last month, ground-penetrating radar detected a potential 751 unmarked graves, in Cowessess First Nation, Saskatchewan, Canada July 6, 2021. Liam Richards/Pool via REUTERS

Chief Cadmus Delorme, left to right, Prime Minister Justin Trudeau, and Saskatchewan Premier Scott Moe walk though a field prior to a ceremony at the site of a former residential school where small flags which were placed, last month, in spots where ground-penetrating radar detected a potential 751 unmarked graves, in Cowessess First Nation, Saskatchewan, Canada July 6, 2021. Liam Richards/Pool via REUTERS

Saskatchewan Premier Scott Moe, Chief Cadmus Delorme and Prime Minister Justin Trudeau walk though a field prior to a ceremony at the site of a former residential school where small flags which were placed, last month, in spots where ground-penetrating radar detected a potential 751 unmarked graves, in Cowessess First Nation, Saskatchewan, Canada July 6, 2021. Liam Richards/Pool via REUTERS

The Jet d'Eau fountain is seen behind Swiss army radar station ahead of the June 16 summit between U.S. President Joe Biden and Russian President Vladimir Putin, in Geneva, Switzerland, June 11, 2021. REUTERS/Denis Balibouse

Swiss army radar station standing near Villa La Grange, with Saint Peter's Cathedral in the back, is seen ahead of the June 16 summit between U.S. President Joe Biden and Russian President Vladimir Putin, in Geneva, Switzerland, June 11, 2021. REUTERS/Denis Balibouse

Swiss army radar station is seen near Villa La Grange ahead of the June 16 summit between U.S. President Joe Biden and Russian President Vladimir Putin, in Geneva, Switzerland, June 11, 2021. REUTERS/Denis Balibouse

People take photos of Swiss army radar station near Villa La Grange ahead of the June 16 summit between U.S. President Joe Biden and Russian President Vladimir Putin, in Geneva, Switzerland, June 11, 2021. REUTERS/Denis Balibouse

Swiss army radar station is seen near Villa La Grange ahead of the June 16 summit between U.S. President Joe Biden and Russian President Vladimir Putin, in Geneva, Switzerland, June 11, 2021. REUTERS/Denis Balibouse

Constructions of a Soviet made over-the-horizon (OTH) radar system "Duga" are seen near the Chernobyl Nuclear Power Plant, Ukraine, April 12, 2021. Picture taken with a drone April 12, 2021. REUTERS/Gleb Garanich

Sriwijaya Air SJ-182, a Boeing 737-500 aircraft, plunged into the sea on January 9 shortly after departing from Indonesia’s capital Jakarta with 62 people on board. The domestic flight disappeared from radar screens four minutes after take-off.

A Sriwijaya Air flight plunged into the sea after departing from Indonesia’s capital Jakarta with 62 people on board. The Boeing 737-500 disappeared from radar screens four minutes after take-off on January 9.

La carte montre la trajectoire du Boeing 737-500 exploité par Sriwijaya Air qui a disparu des radars samedi après avoir quitté Djakarta.

Carme Artigas, head of Spain's state digital and artificial intelligence unit, poses holding a mobile phone with the Radar Covid app before an interview with Reuters in Madrid, September 16, 2020. REUTERS/Sergio Perez

Carme Artigas, head of Spain's state digital and artificial intelligence unit, poses holding a mobile phone with the Radar Covid app before an interview with Reuters in Madrid, September 16, 2020. REUTERS/Sergio Perez

Carme Artigas, head of Spain's state digital and artificial intelligence unit, poses holding a mobile phone with the Radar Covid app before an interview with Reuters in Madrid, September 16, 2020. REUTERS/Sergio Perez

A Skyguide staff sits in front of a radar during a media visit to the newly built control tower of the military and civil airport in Payerne, Switzerland August 13, 2020. REUTERS/Denis Balibouse

An Ecuadorian navy officer looks at a radar after a fishing fleet of mostly Chinese-flagged ships was detected in an international corridor that borders the Galapagos Islands' exclusive economic zone, in the Pacific Ocean, August 7, 2020. Picture taken August 7, 2020. REUTERS/Santiago Arcos

An Ecuadorian navy officer looks at a radar after a fishing fleet of mostly Chinese-flagged ships was detected in an international corridor that borders the Galapagos Islands' exclusive economic zone, in the Pacific Ocean, August 7, 2020. Picture taken August 7, 2020. REUTERS/Santiago Arcos

An Ecuadorian navy officer looks at a radar after a fishing fleet of mostly Chinese-flagged ships was detected in an international corridor that borders the Galapagos Islands' exclusive economic zone, in the Pacific Ocean, August 7, 2020. Picture taken August 7, 2020. REUTERS/Santiago Arcos

The village of Spangdahlem and radar towers of the U.S. Spangdahlem Air Base are seen through a fence in the Eifel region near Bitburg, western Germany, July 30, 2020. REUTERS/Wolfgang Rattay

Radar towers of the U.S. Spangdahlem Air Base are seen near the village of Spangdahlem, near Bitburg, western Germany, July 30, 2020. REUTERS/Wolfgang Rattay

General view shows Santa Maria di Falerii, former Cistercian abbey in Falerii Novi, after researchers announced they were able to map the entire ancient Roman city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

General view shows Santa Maria di Falerii, former Cistercian abbey in Falerii Novi, after researchers announced they were able to map the entire ancient Roman city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

The detail of Porta di Giove, the main entrance to the ancient Roman city of Falerii Novi, which is mostly buried underground, is seen after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

Porta di Giove, the main entrance to the ancient Roman city of Falerii Novi, which is mostly buried underground, are seen after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

Porta di Giove, the main entrance to the ancient Roman city of Falerii Novi, which is mostly buried underground, are seen after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

History passionate Raniero Pedica shows a map of the Ancient Roman city of Falerii Novi, which is mostly buried underground after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

A view shows the remains of the ancient Roman city of Falerii Novi, which is mostly buried underground, after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

A view shows the remains of the ancient Roman city of Falerii Novi, which is mostly buried underground, after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

A view shows the remains of the ancient Roman city of Falerii Novi, which is mostly buried underground, after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

A view shows the remains of the ancient Roman city of Falerii Novi, which is mostly buried underground, after researchers announced they were able to map the entire city using ground-penetrating radar (GPR) technology, near Rome, Italy, June 9, 2020. REUTERS/Yara Nardi

A man wearing a face mask is seen in front of a radar tower at Hongqiao International Airport in Shanghai, following the coronavirus disease (COVID-19) outbreak, China May 19, 2020. REUTERS/Aly Song

Radar sensors are shown own a Hyundai electric vehicle as self driving company Pony.ai begins to provide autonomous electric vehicles to deliver packages from local e-commerce platform Yamibuy during the outbreak of the coronavirus disease (COVID-19) in Irvine, California, U.S., April 28, 2020. REUTERS/Mike Blake

Oculii CEO Steven Hong shows the company's radar kit at the CES tech show in Las Vegas, Nevada, U.S. January 5, 2020. Oculii's AI software helps boost the resolution of radars so it can be used in self-driving cars. Picture taken January 5, 2020. REUTERS/Jane Lanhee Lee

Oculii CEO Steven Hong shows the company's radar kit at the CES tech show in Las Vegas, Nevada, U.S. January 5, 2020. Oculii's AI software helps boost the resolution of radars so it can be used in self-driving cars. Picture taken January 5, 2020. REUTERS/Jane Lanhee Lee

Father Abbot Abibos turns on the radar in the wheelhouse. A boat intended as a mobile Georgian Orthodox monastery, featuring a chapel decorated with wall frescos, has been at anchor in the Dutch harbour town of Vlissingen for two years while being refurbished. The monastery expects to set sail from Vlissingen in spring, to visit Georgian communities around Europe, Vlissingen, Netherlands December 30, 2019. Picture taken December 30, 2019. REUTERS/Piroschka van de Wouw REFILE - CORRECTING NAME

A radar 75/10 of the Swiss Army is displayed during the presentation of the defence system ahead of the Refugees Forum at the United Nations, near Lake Geneva, Switzerland, December 16, 2019. REUTERS/Denis Balibouse

A radar 75/10 and a cannon 63/12 of the Swiss Army are displayed during the presentation of the defence system ahead of the Refugees Forum at the United Nations, near Lake Geneva, Switzerland, December 16, 2019. REUTERS/Denis Balibouse

A radar 75/10 and a cannon 63/12 of the Swiss Army are displayed during the presentation of the defence system ahead of the Refugees Forum at the United Nations, near Lake Geneva, Switzerland, December 16, 2019. REUTERS/Denis Balibouse

A radar 75/10 and a cannon 63/12 of the Swiss Army are displayed during the presentation of the defence system ahead of the Refugees Forum at the United Nations, near Lake Geneva, Switzerland, December 16, 2019. REUTERS/Denis Balibouse

A damaged traffic speed camera is seen in Nice, France, November 4, 2019. REUTERS/Eric Gaillard

An airplane flies past a newly installed "noise radar", a measuring device that can precisely measure and locate sounds from a moving vehicles as well as register their licence plates at Villeneuve-le-Roi, a town next to Paris airport Orly, France, August 30, 2019. REUTERS/Charles Platiau

A newly installed "noise radar", a measuring device that can precisely measure and locate sounds from a moving vehicles as well as register their licence plates, is seen at Villeneuve-le-Roi, a town next to Paris airport Orly, France, August 30, 2019. REUTERS/Charles Platiau

A newly installed "noise radar", a measuring device that can precisely measure and locate sounds from a moving vehicles as well as register their licence plates, is seen at Villeneuve-le-Roi, a town next to Paris airport Orly, France, August 30, 2019. REUTERS/Charles Platiau

An airplane flies past a newly installed "noise radar", a measuring device that can precisely measure and locate sounds from a moving vehicles as well as register their licence plates at Villeneuve-le-Roi, a town next to Paris airport Orly, France, August 30, 2019. REUTERS/Charles Platiau

An airplane flies past a newly installed "noise radar", a measuring device that can precisely measure and locate sounds from a moving vehicles as well as register their licence plates at Villeneuve-le-Roi, a town next to Paris airport Orly, France, August 30, 2019. REUTERS/Charles Platiau

A radar is seen on the monitoring tower of USS Boxer (LHD-4) in the Arabian Sea off Oman July 16, 2019. Picture taken July 16, 2019. REUTERS/Ahmed Jadallah

Visitors inspect constructions of a former Soviet Union over-the-horizon (OTH) radar system "Duga" near the Chernobyl Nuclear Power Plant, near Chernobyl, Ukraine June 2, 2019. Picture taken June 2, 2019. REUTERS/Valentyn Ogirenko

A radar tower is seen on the beach of Sangatte, near Calais, France February 19, 2019. REUTERS/Benoit Tessier

German Chancellor Angela Merkel stands in front of a large screen introducing NEC's satellite-mounted radar system for monitoring urban infrastructure and disaster prevention as she visits NEC Future Creation Hub at the headquarters of NEC in Tokyo, Japan, February 5, 2019. REUTERS/Kim Kyung-hoon

German Chancellor Angela Merkel stands in front of a large screen introducing NEC's satellite-mounted radar system for monitoring urban infrastructure and disaster prevention as she visits NEC Future Creation Hub at the headquarters of NEC in Tokyo, Japan, February 5, 2019. REUTERS/Kim Kyung-hoon

German Chancellor Angela Merkel stands in front of a large screen introducing NEC's satellite-mounted radar system for monitoring urban infrastructure and disaster prevention as she visits NEC Future Creation Hub at the headquarters of NEC in Tokyo, Japan, February 5, 2019. REUTERS/Kim Kyung-hoon

German Chancellor Angela Merkel stands near a large screen introducing NEC's satellite-mounted radar system for monitoring urban infrastructure and disaster prevention as she visits NEC Future Creation Hub at the headquarters of NEC in Tokyo, Japan, February 5, 2019. REUTERS/Kim Kyung-hoon

German Chancellor Angela Merkel stands in front of a large screen introducing NEC's satellite-mounted radar system for monitoring urban infrastructure and disaster prevention as she visits NEC Future Creation Hub at the headquarters of NEC in Tokyo, Japan, February 5, 2019. REUTERS/Kim Kyung-hoon

German Chancellor Angela Merkel stands in front of a large screen introducing NEC's satellite-mounted radar system for monitoring urban infrastructure and disaster prevention as she visits NEC Future Creation Hub at the headquarters of NEC in Tokyo, Japan, February 5, 2019. REUTERS/Kim Kyung-hoon

A traffic speed camera is covered with white painting to block its operation in Nice, France, January 11, 2019. REUTERS/Eric Gaillard