Little Red Dots are extremely compact objects recently observed by NASA's James Webb Space Telescope. Using supercomputers and LRD data from JWST, a team of astronomers compared and found good agreement with observed data to models that employed a ‘heavy seed’ vs. a 'light seed' hypothesis of black hole formation in the early universe. 

Space-based distributed array telescope formations, through multi-telescope collaborative observation and long-baseline optical interferometry, can significantly enhance deep space exploration capabilities, providing key technological support for missions such as asteroid monitoring and the search for extraterrestrial life. However, the measurement and control performance of such formations is highly dependent on the precision of intertelescope baseline measurements. Frequency-sweeping interferometry (FSI) technology, with its significant advantages—including freedom from the ambiguity range limitation, capability for non-cooperative target measurement, strong anti-interference ability in complex space environments, and high maturity of core components—has emerged as the most promising technical approach for baseline measurement in space-based distributed array telescope formations. Nevertheless, advancing this technology toward aerospace engineering applications still faces two major challenges: suppressing optical frequency-sweep nonlinearity and eliminating dynamic ranging errors. Currently, using electro-optic modulation to generate highly linear, synchronized, symmetrically sweeping positive and negative sidebands—establishing a frequency-sweeping interferometry system based on electro-optic sideband modulation—represents an effective method to address the issues of sweep nonlinearity and Doppler dynamic error. However, frequency-sweeping interferometry systems based on electro-optic sideband modulation lack a traceable on-orbit optical frequency-sweep reference, making it difficult to ensure long-term stable measurement and accuracy maintenance on orbit. Therefore, further research into high-precision electro-optic sideband modulation-based frequency-sweeping interferometry methods with traceable sweep references is of great significance for advancing the development of baseline measurement technology for space-based distributed array telescope formations.

Recently, in a research article published in Space: Science & Technology, Academician Weimin Bao's team at Xidian University proposed a double-sideband frequency-sweeping interferometry (DSB-FSI) technique based on Fabry–Pérot (F-P) etalon calibration. The study established an intersatellite baseline measurement architecture comprising an electro-optic modulation-based double-sideband frequency-swept laser source module, an F-P etalon-based optical frequency-sweep rate calibration module, and an optical hybrid quadrature detection module. By acquiring beat signals generated by the symmetrically sweeping sidebands through quadrature detection, the Doppler error in dynamic ranging is eliminated. Online calibration of the optical frequency-sweep rate is achieved based on the time-domain intervals of the F-P etalon's resonance peaks. Experimental results demonstrate that the ranging system reduces measurement drift error from 20.11 μm to 13.38 μm over a 5.7 m baseline, improving stability by 33.47%. The ranging accuracy reaches 44.30 μm over a 10 m range. Within a velocity range of 5–20 mm/s, the system exhibits a displacement measurement linearity better than 0.99999, a velocity measurement deviation of less than −16.80 μm/s, and a vibration measurement error of less than 0.08 μm. This study provides a feasible technical solution for high-precision and stable intersatellite baseline measurement in the "MEAYIN" project.

In the largest genomic mapping of Africa's elephants, an international team of researchers shows that elephant history is defined by the ability to move across large distances and exchange genes throughout the African continent. But as the elephants’ living space is becoming increasingly patchy, the study documents the visible genetic consequences of isolation – and points to approaches that help to incorporate genomics into current and future elephant conservation.

New Curtin University-led research has used a radio telescope that spans the Earth to snap images that measure the immense power of jets from black holes, confirming scientists’ theories of how black holes help shape the structure of the Universe.

From lazy ripples to towering breakers, the mechanics of ocean waves should vary widely from one planet to another, according to a model developed by scientists at MIT and the Woods Hole Oceanographic Institute.

In a new study, University of Washington researchers show that an Earth-sized planet likely needs at least 20 to 50% of the water in Earth’s oceans to maintain a critical natural cycle that keeps water on the surface. These new parameters could exclude many exoplanets in the so-called habitable zone.

Astronomers are puzzled by the existence of extremely massive black holes—up to a billion times the mass of the Sun—forming less than a billion years after the Big Bang, far earlier than current theories predict. Standard models of black hole growth cannot explain how they became so large so quickly. New research suggests that energy from decaying dark matter may have altered early galaxies’ chemistry, allowing some to collapse directly into massive black holes instead of forming stars.

To strengthen collaboration with industry, while enhancing warfighter readiness and lethality, the Office of Naval Research (ONR) — to include the Naval Research Laboratory (NRL) and ONR’s international arm, ONR Global — will host an exhibit at the Navy League’s Sea-Air-Space Exposition, April 20-22, at the Gaylord National Resort and Convention Center in National Harbor, Maryland.