Recent Comments

    Near-infrared Spectrograph (NIRSpec) tagged posts

    Astronomers explore the double nucleus of galaxy NGC 4486B

    December 26, 2025, Categories  Astronomy/Space

    Astronomers explore the double nucleus of galaxy NGC 4486B

    Using the James Webb Space Telescope (JWST), an international team of astronomers has observed an elliptical galaxy known as NGC 4486B. Results of the observational campaign, published Dec. 16 on the arXiv preprint server, deliver important insights into the properties of the double nucleus of this galaxy.

    Why does NGC 4486B have a double nucleus?
    NGC 4486B (also known as VCC1279) is a compact elliptical galaxy at the center of the Virgo Cluster. It has a small effective radius of about 620 light years, an absolute magnitude of 17.6 mag, and its total stellar mass is estimated to be approximately 6 billion solar masses.

    Hubble Space Telescope observations of NGC 4486B have revealed that it hosts a double nucleus, as does the Andromeda galaxy...

    Read More

    Webb spies Chariklo Ring System with High-Precision Technique

    January 26, 2023, Categories  Astronomy/Space

    Graphic titled “Centaur 10199 Chariklo: Surface Composition; NIRSpec PRISM.” The graphic shows a reflectance spectrum in the form of a graph of the Brightness of Light (relative reflectance) on the vertical y-axis versus Wavelength of Light in microns on the horizontal x-axis. The spectrum is plotted as a continuous jagged white line. The overall shape of the line is curvy, with broad peaks and valleys. Three prominent valleys are highlighted in blue and labeled “Water Ice, H2O.” In the background is a grayscale illustration of Chariklo and its rings, as seen from an oblique angle. For more details, see the Text Description PDF.
    Webb captured a spectrum with its Near-infrared Spectrograph (NIRSpec) of the Chariklo system on Oct. 31, shortly after the occultation. This spectrum shows clear evidence for crystalline water ice, which was only hinted at by past ground-based observations. Image credit: NASA, ESA, CSA, Leah Hustak (STScI). Science: Noemí Pinilla-Alonso (FSI/UCF), Ian Wong (STScI), Javier Licandro (IAC). Download the full-resolution version from the Space Telescope Science Institute.

    In 2013, Felipe Braga-Ribas and collaborators, using ground-based telescopes, discovered that Chariklo hosts a system of two thin rings. Such rings had been expected only around large planets such as Jupiter and Neptune.

    The astronomers had been watching a star as Chariklo passed in front of it, blocking the starlight...

    Read More