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JWST tracks more than 100 magnified stellar events in the Dragon galaxy

from Phys.org

Using the James Webb Space Telescope (JWST), a team of astronomers identified 104 magnified stellar events in a galaxy known as the Dragon, located around 6.5 billion light-years away. This discovery more than doubles the previous record of 44 such detections in the same galaxy. Because these kinds of events reveal some of the most luminous stars and likely the presence of dark matter, this study offers a rare look at the galaxy's stellar population along with a possible hint at the nature of dark matter.

explained

The James Webb Space Telescope (JWST) is a space telescope designed to conduct infrared astronomy. It is the largest telescope in space, and is equipped with high-resolution and high-sensitivity instruments, allowing it to view objects too old, distant, or faint for the Hubble Space Telescope. This enables investigations across many fields of astronomy and cosmology, such as observation of the first stars and the formation of the first galaxies, and detailed atmospheric characterization of potentially habitable exoplanets.

Despite Webb's mirror diameter being 2.7 times larger than that of the Hubble Space Telescope, it produces images of comparable resolution because it observes in the infrared spectrum, which has longer wavelengths than the Hubble's visible spectrum. The longer the wavelength the telescope is designed to observe, the larger the information-gathering surface (mirrors in the infrared spectrum or antenna area in the millimeter and radio ranges) required to achieve the desired resolution.

From Wikipedia: James Webb Space Telescope (CC BY-SA 4.0) ↗
so what

Gravitational lensing gives astronomers a way to see individual stars in galaxies too distant to resolve otherwise, and the findings add clues about dark matter.

more on this

Illustrative photo · Lensshoe_hubble.jpg : ESA/Hubble & NASA derivative work: Bu…, Public domain, via Wikimedia Commons