Latest news with #SquareKilometreArray
Yahoo
6 hours ago
- Science
- Yahoo
A radio signal from the beginning of the universe could reveal how everything began
A radio signal from the early universe could allow us to understand how everything that surrounds us began. The signal – known as the 21-centimetre signal – could finally let us understand how the first stars and galaxies switched on, and brought the universe from darkness to light. 'This is a unique opportunity to learn how the universe's first light emerged from the darkness,' said co-author Anastasia Fialkov from Cambridge University, in a statement. 'The transition from a cold, dark universe to one filled with stars is a story we're only beginning to understand.' The signal comes to us from more than 13 billion years ago, just a hundred million years after the Big Bang. The faint glow is created by hydrogen atoms that fill up the space between regions of space where stars are being formed. Scientists now believe they will be able to use the nature of that signal to better understand the early universe. They will do that with a radio antenna called REACH – the Radio Experiment for the Analysis of Cosmic Hydrogen – which will try and capture radio signals to reveal data about the beginnings of the universe. To better understand how that project might work, researchers created a model that predicted how REACH as well as another project called the Square Kilometre Array will be able to provide information about the masses and other details of the first stars. 'We are the first group to consistently model the dependence of the 21-centimetre signal of the masses of the first stars, including the impact of ultraviolet starlight and X-ray emissions from X-ray binaries produced when the first stars die,' said Professor Fialkov. 'These insights are derived from simulations that integrate the primordial conditions of the universe, such as the hydrogen-helium composition produced by the Big Bang.' 'The predictions we are reporting have huge implications for our understanding of the nature of the very first stars in the Universe,' said co-author Eloy de Lera Acedo, Principal Investigator of the REACH telescope. 'We show evidence that our radio telescopes can tell us details about the mass of those first stars and how these early lights may have been very different from today's stars. 'Radio telescopes like REACH are promising to unlock the mysteries of the infant Universe, and these predictions are essential to guide the radio observations we are doing from the Karoo, in South Africa.' The work is described in a new paper, 'Determination of the mass distribution of the first stars from the 21-cm signal', published in the journal Nature Astronomy.
The Independent
11 hours ago
- Science
- The Independent
Space signal could reveal how universe turned from dark to light
A radio signal from the early universe, known as the 21-centimetre signal, offers a unique opportunity to understand how the first stars and galaxies emerged. This faint glow originates from over 13 billion years ago, approximately 100 million years after the Big Bang, and is created by hydrogen atoms. Scientists plan to use a radio antenna called REACH (Radio Experiment for the Analysis of Cosmic Hydrogen) to capture these signals and gather data about the universe's beginnings. Researchers developed a model predicting how REACH and the Square Kilometre Array can provide information about the masses and other details of the first stars. The work, published in Nature Astronomy, suggests that radio telescopes like REACH can reveal crucial details about the nature and mass of these early stars, which may have differed from today's stars.
Yahoo
12-06-2025
- Science
- Yahoo
There's a Giant Problem With SpaceX's Starlink Satellites
Astronomers' attempts to peer into the earliest reaches of the universe could be threatened by thousands of SpaceX Starlink satellites leaking radio emissions that ruin observations made with highly sensitive telescopes. As New Scientist reports, a team of researchers led by Curtin University radio astronomy professor Steven Tingay tracked the signals of almost 2,000 Starlink satellites, with the help of a prototype telescope from the Square Kilometre Array, which is currently under construction in Australia. They found that a third of the data at specific frequencies was being threatened by the radio emissions released by the Starlink satellites, a worrying sign that the Elon Musk-led space company could be hampering our efforts to study the early universe. And the problem is rapidly getting worse. As of May, the company has more than 7,600 satellites in low-Earth orbit, roughly two-thirds of all the operational satellites in orbit combined, and has plans to expand the constellation to tens of thousands. As detailed in a yet-to-be-peer-reviewed paper, Tingay and his colleagues suggested the small satellites' electronics could be accidentally transmitting radio signals through their antennas. In radio observations, they're extremely hard to miss. "If you look at the signal strength produced by these unintended emissions, it's not unusual for them to be comparable to the brightest natural radio sources in the sky," Tingay told New Scientist. "It's like taking the strongest sources in the sky and putting a bunch more artificial ones in the sky and making them move around a lot — that has a lot of impact, especially on experiments that seek to be ultra-sensitive." Interestingly, SpaceX is emitting signals at ranges that are protected by the International Telecommunication Union, explicitly for the purpose of radio astronomy. However, whether Musk's space firm is acting illegally remains unclear as the transmissions are likely unintentional. "No one's breaking any rules from SpaceX or Starlink — these types of emissions are not regulated," Tingay told New Scientist. "But it is starting to become a discussion in the ITU as to how regulations over this type of emission could be introduced." Besides releasing radio transmissions, SpaceX's satellites have previously been found to be extremely bright, showing up as enormous streaks in night sky observations. Since then, anti-reflective coatings and manipulating their orientations have made them somewhat less disruptive to astronomical surveys. In 2023, SpaceX introduced a "distributed Bragg reflector" for its Starlink satellites, which is composed of multiple layers of plastic to scatter light, but still allow radio waves to pass through. The effectiveness of these reflectors remains unclear. Astronomers are now calling for SpaceX to address the problem of unintentional radio emissions as well. "The best way to stop this unintended emission is for the satellites to either reduce it or to stop it," coauthor and Curtin University masters student Dylan Grigg told New Scientist. "From the operators' side, it would be great to have mitigations on the satellite, and SpaceX has done that already in optical astronomy." Fortunately, SpaceX has been open to dialogue, Grigg and Tingay found after reaching out to the company. More on Starlink: United Airlines Shuts Down Starlink WiFi Service on Its Planes After the Antennae Caused Problems With Its Jets' Equipment
The Citizen
11-06-2025
- Science
- The Citizen
SA's MeerKAT telescope joins forces with European VLBI Network
This is a new chapter for high-resolution radio astronomy, enabling scientists to study the universe in greater detail than ever before. FILE: Part of the ensemble of dishes forming South Africa's MeerKAT radio telescope is seen in Carnarvon on July 16, 2016. Picture: Mujahid Safodien/ AFP South Africa's MeerKAT telescope has joined forces with the European VLBI Network (EVN), one of the world's most sensitive and advanced very long baseline interferometry (VLBI) systems. Their partnership sets a new standard for global collaboration and significantly enhances both resolution and sensitivity, opening new avenues for scientific exploration and a new era of radio astronomy. Space exploration It is also a new chapter for high-resolution radio astronomy, enabling scientists to study the universe in greater detail than ever before. The collaboration has already delivered impressive results, with EVN researchers capturing enhanced images of energetic plasma jets from the supermassive black hole J0123+3044. This sets the stage for a new wave of scientific breakthroughs in understanding cosmic phenomena. 'Proud moment' Minister of Science, Technology and Innovation Blade Nzimande said the achievement is a proud moment for South African science and a powerful demonstration of what international collaboration can accomplish. 'Integrating MeerKAT into the EVN marks a giant leap for precision radio astronomy and lays vital groundwork for the future Square Kilometre Array (SKA)-VLBI era'. The Joint Institute for VLBI in Europe (JIVE), headquartered in the Netherlands, coordinated the EVN's participation and played a central role in data processing and image development, working closely with the South African Radio Astronomy Observatory's (SARAO) engineering and science teams to ensure the mission's success. ALSO READ: Anyone out there? Astronomers find signs of life on distant planet Universe exploration Reflecting on MeerKAT's remarkable capabilities and its collaborative observations with the EVN, SARAO Managing Director Pontsho Maruping said the telescope has been highly successful in its mission to explore the radio sky with unprecedented detail, capturing images of some of the universe's largest-scale structures. 'At the same time, we strongly emphasise collaborating with other instruments as we continue to develop MeerKAT's scientific capabilities before its eventual integration into the SKA-Mid telescope'. 'Great achievement' Jive Council Chair Jessica Dempsey applauded the 'great' achievement by the SARAO team. 'This collaboration not only showcases the power of international partnerships in radio astronomy but also paves the way for transformative scientific discoveries through cutting-edge technological innovation.' The achievement is not just a technological milestone; it is also a powerful example of global scientific unity, with South Africa proudly at the forefront of the world's expanding window on the universe. ALSO READ: SA takes giant leap with Prime telescope to enhance exoplanet discovery [VIDEO]
IOL News
10-06-2025
- Science
- IOL News
Elon Musk's Starlink: a threat to South Africa's astronomical research?
One of the 64 MeerKAT Telescopes observing our skies. Image: UWC The prospect of Elon Musk's satellite internet venture, Starlink, expanding its operations to South Africa has generated considerable excitement, particularly for its potential to bridge the digital divide in rural communities. However, experts in the field of astronomy are raising concerns about the unintended consequences of satellite constellations on South Africa's world-class radio telescopes. University of the Western Cape (UWC) Professor Lerothodi Leeuw recently spoke to Cape Talk radio about the disruptive impact that Starlink and similar satellite networks could have on the country's premier astronomical facilities. Among those at risk are the Southern African Large Telescope (SALT), a state-of-the-art observatory in Sutherland, and the ambitious Square Kilometre Array (SKA) project, designed to unlock new insights into the universe. Prof Leeuw likened the interference caused by satellites to a form of 'photo-bombing,' where artificial radio signals intrude upon critical observations. He emphasised that this issue is not new, but Starlink's growing prominence has renewed discussions around mitigating the effects of space-based transmissions. South Africa has invested significantly in its radio telescope infrastructure, and authorities have implemented strict regulations to minimise interference from terrestrial sources. The SKA site, for instance, is located within a designated radio-quiet zone. However, Prof Leeuw pointed out that these safeguards do not extend beyond national borders, leaving space-based satellites outside the scope of local regulations. Professor Lerothodi Leeuw Image: UWC 'We don't control low Earth-orbiting satellites,' he noted, highlighting that Starlink is not the only operator deploying satellite constellations. Other ventures, such as OneWeb and Project Kuiper, also contribute to the challenge. Despite the difficulties, Prof Leeuw remains optimistic that measures can be put in place to mitigate the problem. He suggested that temporarily disabling satellites while they pass over sensitive areas could help prevent interference. 'There is potential to mitigate the problem by turning off satellites for just a few seconds as they cross the region, without affecting transmission elsewhere,' he explained. Some scientists have already approached Starlink to explore solutions, leading to adjustments in satellite design. These include adding optical reflectors to redirect light away from telescopes or modifying the satellites' surfaces to reduce glare. However, altering orbital paths to completely avoid interference remains impractical. Prof Leeuw underscored the significance of this issue within the scientific community. He revealed that a conference dedicated entirely to tackling satellite interference was held last year, although discussions on radio astronomy only occupied half a day, showing that the subject, while growing in importance, remains under-addressed. As satellite constellations continue to proliferate, experts in astronomy are urging operators to take more proactive steps to minimise their footprint on scientific exploration. The balance between global connectivity and preserving the integrity of astronomical research is a delicate one, and finding solutions will require coordinated effort between governments, scientists and satellite providers alike.
