WASHINGTON– A multibillion-dollar radio telescope is moving into its building and construction phase while still working to raise financing and offer with satellite megaconstellations whose interference “alter the video game” for their plans.
In a June 29 talk at the yearly meeting of the European Astronomical Society, Philip Diamond, director general of the Square Kilometer Array (SKA) Observatory, revealed that the observatorys council had formally approval strategies to move into the building and construction stage of the radio telescope.
SKA is 2 different facilities. SKA-Low, in Western Australia, will eventually be a variety of more than 130,000 antennas carrying out observations at low frequencies. SKA-Mid will include 197 dishes in South Africa for midrange radio frequencies, including 64 meals of the existing MeerKAT variety there.
The councils choice enabled the SKA to move into its building and construction phase on July 1. “We wont see shovels in the round on the very first of July,” he stated, however rather demands for proposition to develop various elements of the two facilities. The observatory anticipates that construction to be completed by 2029.
The SKA is created to support a vast array of astronomy research study, from research studies of dark energy and pulsars to astrobiology. The principle for the SKA dates back 3 decades, when astronomers initially thought about ideas for a radio telescope that, as the name recommends, would span a square kilometer. Those concepts later progressed to the present design with centers on two continents.
One technological difficulty that has actually also developed over that time is radio-frequency interference. “We radio astronomers have actually been utilized to dealing with the disturbance from satellites and aircraft systems,” Diamond stated at a June 29 press rundown. “What the megaconstellations do is that they change the video game for us.”
The difference is the large number of satellites, with proposals for potentially lots of 10s of countless satellites. Many will be running on frequencies that SKA-Mid, which runs between 350 megahertz and 15.3 gigahertz, is tuned to observe. While radio astronomy has priority for a couple of bands because range, the satellites will be broadcasting– lawfully, he acknowledged– on numerous others.
Diamond said the SKA was in technical discussions with satellite operators on mitigation measures “that would substantially limit the effect on the SKA telescopes.” He didnt elaborate on the particular measures.
During a talk at the conference July 2, Federico Di Vruno, spectrum manager of the SKA Observatory, said the observatory had established “flagging and excision” technologies to identify radio-frequency interference by satellites and removing it from the data. “This represents a loss of observing time,” he said, but such interference from the constellations by OneWeb and SpaceX would represent less than four percent of observations.
Nevertheless, he cautioned that even if the problem is workable with those constellations, future systems would just increase the issue. That consists of expansions of both OneWeb and SpaceXs Starlink as well as the proposed Chinese Guowang constellation that could ultimately have 13,000 satellites.
” The possibility of constellations of 10s of countless satellites is incredibly concerning for radio astronomy,” he stated. Operators, he recommended, could help by concurring not to transfer when their satellites are passing over “radio peaceful zones” surrounding the antennas.
The SKA deals with a different difficulty: raising the funding required to develop the 2 centers. The observatory estimates spending 2 billion euros ($ 2.4 billion) to construct and operate the SKA over the next years. Diamond stated that the SKA Observatory, a multinational organization, was still working to raise the money from more than a lots nations.
” We have raised the big majority of the needed funding,” Diamond said, but declined to offer a particular figure. “The members would not have actually been prepared to go ahead with the decision to proceed with building and construction if they didnt feel comfy the requisite funds would flow.”
” We have some years in front of us to raise the additional funds that we require, which is very much a minority,” he said.
Significantly missing from the SKA Observatory is the United States. Diamond stated that American astronomers were associated with early preparation for the radio telescope, and at one point the United States was expected to supply a third of the financing. The SKA did not emerge as a priority in the 2010 astrophysics decadal survey, where American astronomers instead selected other ground-based telescopes as more worthy of funding.
” The timing of the decadal survey didnt line up with the SKA timing,” he stated. “The U.S. SKA activities did not get a high adequate top priority, so the U.S. funds were– sadly, from our perspective– directed to other highly deserving tasks.”
American astronomers, he added, remain associated with SKA activities, including evaluations. “Its certainly not a divorce,” he said. “Its simply a fact of life from the 2010 decadal study.”

The concept for the SKA dates back 3 years, when astronomers initially thought about concepts for a radio telescope that, as the name recommends, would cover a square kilometer. The SKA deals with a separate challenge: raising the financing required to construct the two centers. The observatory estimates costs 2 billion euros ($ 2.4 billion) to run the ska and build over the next decade. Diamond stated that the SKA Observatory, a multinational organization, was still working to raise the money from more than a lots nations.
The SKA did not emerge as a top priority in the 2010 astrophysics decadal survey, where American astronomers instead chosen other ground-based telescopes as more deserving of funding.