Astronomers have indefinitely stopped looking through 13 existing telescopes at the summit of Mauna Kea in Hawaii while protesters block a road in an attempt to prevent the construction of a giant new observatory.

Dozens of researches around the world will not be able to gather data and study the skies as a result of the move.

Observations will not resume until staff have consistent access to the summit, said Jessica Dempsey, the deputy director of the East Asian Observatory, one of the existing telescopes.

The announcement came as Native Hawaiian protesters blocked the base of the road for a second day.

They object to the construction of the 1.4 billion US dollars (£1.1 billion) Thirty Metre Telescope, which is expected to be one of the world’s most advanced when it is built, out of concern it will further harm an area some Native Hawaiians consider sacred.

Giant Telescope
Demonstrators gather to block a road at the base of Hawaii’s tallest mountain (Caleb Jones/AP)

Hawaii authorities have not arrested any protesters, although have indicated they would.

Jason Redulla, chief of the state Division of Conservation and Resources Enforcement, said law enforcement was focused on preparing a path to construction.

Ms Dempsey said consistent access to the summit is needed to ensure the safety of staff.

“Our science time is precious but in this case, our priority is just to make sure all of our staff is safe,” she said.

The East Asian Observatory was scheduled to study carbon monoxide clouds in star-forming regions inside the Milky Way galaxy.

Ms Dempsey called the clouds “the DNA of how baby stars form” and said they help astronomers figure out how stars work.

Protesters said they told law enforcement they would allow telescope technicians to pass so long as they would be allowed to drive one car to the summit each day for cultural and religious practices.

They said they would not allow National Guard members to pass.

No agreement was reached.

“We are at a standstill,” said Kaho’okahi Kanuha, one of the protest leaders.

He told reporters that efforts to stop the development were about protecting the indigenous people of Hawaii.

“This is about our right to exist … The way our kupuna existed,” he said, using the Hawaiian word for elder.

“We fight and resist and we stand, or we disappear forever,” he said.

Governor David Ige announced plans last week to close the summit access road on Monday to allow construction to begin.

The decision attracted hundreds of protesters to the site, who formed road blocks.

Giant Telescope
Demonstrators gather to protest against the construction of a giant telescope on land that some Native Hawaiians consider sacred (Caleb Jones/AP)

Other Native Hawaiians say they do not believe the telescope will desecrate Mauna Kea.

Most of the cultural practices on the mountain take place away from the summit, said Annette Reyes, a Native Hawaiian from the Big Island.

“It’s going to be out of sight, out of mind,” she said.

Ms Reyes said Hawaii’s young people can not afford to miss out on educational opportunities, citing telescope officials’ pledge to provide one million dollars every year of the 19-year Mauna Kea sublease to boost science, technology, engineering and maths education.

The telescope’s primary mirror would measure 98 feet (30 metres) in diameter, three times as wide as the world’s largest existing visible-light telescope, with nine times more area.

The company behind the telescope is made up of a group of universities in California and Canada, with partners from China, India and Japan.

The project has been delayed by years of legal battles and demonstrations.

Last year, Hawaii’s supreme court ruled the group had legally obtained a permit for the project.

Telescope opponents last week filed another petition in court, saying the project must post a security bond equivalent to the construction contract cost before starting to build.

The summit of Mauna Kea, Hawaii’s tallest peak, is one of world’s best spots for astronomy because it has clear weather for most of the year and minimal light pollution.