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#astrometry — Public Fediverse posts

Live and recent posts from across the Fediverse tagged #astrometry, aggregated by home.social.

  1. europesays.com/ie/409500/ A Planetary Illusion’s Funeral: Non-detection of a Gaia DR3 Exoplanet Candidate, and the Role of Intermediate-precision Radial Velocities in Gaia Exoplanet Follow-up #AstroPhEP #astrometry #Éire #Exoplanet #GaiaDR3 #HD12800 #Https://astrobiologyCom/2026/03/astronomy #Https://astrobiologyCom/2026/03/imaging #IE #Ireland #Science #spectrograph #StellarCartography #TRES

  2. Earth orientation parameters (Earth 🌍)

    In geodesy and astrometry, earth orientation parameters describe irregularities in the rotation of planet Earth. EOP provide the rotational transform from the International Terrestrial Reference System to the International Celestial Reference System, or vice versa, as a function of time. Earth's rotational velocity is not constant over time.

    en.wikipedia.org/wiki/Earth_or

    #EarthOrientationParameters #Earth #Geodesy #Astrometry

  3. Earth orientation parameters (Earth 🌍)

    In geodesy and astrometry, earth orientation parameters describe irregularities in the rotation of planet Earth. EOP provide the rotational transform from the International Terrestrial Reference System to the International Celestial Reference System, or vice versa, as a function of time. Earth's rotational velocity is not constant over time.

    en.wikipedia.org/wiki/Earth_or

    #EarthOrientationParameters #Earth #Geodesy #Astrometry

  4. @Jlkeeton @BramMeehan @Bellingcat

    I did some archeoastronomy on your image. It appears the image was taken in the evening, about an hour after sunset, roughly in mid-August. The image is looking southwest. See screenshot from planetarium sky simulation software (stellarium.org/).

    I got some help from nova.astrometry.net/ which solved the image (astrometry), as can be seen here:
    nova.astrometry.net/user_image
    and here:
    nova.astrometry.net/user_image

    en.wikipedia.org/wiki/Astromet

    That gave me the orientation of the image (looking southwest, so I knew that this was an evening twilight shot, not morning)...and I adjusted the date and time in planetarium software until I got to a time of year when twilight was involved.

    BTW, one of the best examples of archeoastronomy happened not too far from you:
    en.wikipedia.org/wiki/Moonrise

    #NewMexico #ArcheoAstronomy #Astronomy #Photography #Astrophotography #Astrometry #Bellingcat

  5. Does anyone have an alternative to Astrometry.net? It appears to be down right now.

    #astronomy #Astrometry

  6. Inktober 52 2025 - Week 4 - 'Aquarius'

    Combining the Lunar new year animal with the star sign it's rising from!
    #inktober #inktober52 #snake #aquarius #water #stars #starsign #constellation #zodiac #astrology #astrometry

  7. Join us as we dive into the fascinating world of radio astronomy at the Hartebeesthoek Radio Astronomy Observatory in South Africa. From its NASA origins to cutting-edge VLBI technology,discover how HartRAO plays a crucial role in space exploration and precision measurements of celestial objects.

    webgal.nemethstarproductions.e (CC-BY 4.0)

    #SpaceFridayPhotography #HartRAO #Hartebeesthoek #RadioAstronomy #SpaceScience #Astronomy #Astrometry #SpaceExploration #BlueSkyScience #SouthAfrica #Johannesburg

  8. Here is a lesser-known nebula: #NGC6820, and the open cluster #NGC6823 .

    This shot covers about 1 degree by 1.5 degrees, and is the result of about five hours of data collection over the course of three nights, using two #DwarfII smart telescopes.

    1 hour's worth is without any filters, 1 hour is with a Svbony CLS light pollution filter, and 3 hours with a OIII/HII filter.

    Then I fed the 1237 frames into #Siril and started crunching numbers. 72 frames were not usable, leaving me with 1165. These I stacked, and then ran through the "Hubblematic" #HubblePalette emulator and DSA Star Reduction scripts. Finally I did some additional reprocessing and smoothing with #GooglePhotos.

    Most images of the area cover the cluster, rather than the rather large area of nebulosity that surrounds it, and just concentrate on the (admittedly very pretty) nebula around the cluster. This shot covers a much wider field, and even it does not show the true extent of this faint but magnificent region.

    #Astrometry by Astrometry.net .

    #astronomy #Astrodon #Astrophotography

  9. Earth orientation parameters (Earth 🌍)

    In geodesy and astrometry, earth orientation parameters describe irregularities in the rotation of planet Earth. EOP provide the rotational transform from the International Terrestrial Reference System to the International Celestial Reference System, or vice versa, as a function of time. Earth's rotational velocity is not constant over time.

    en.wikipedia.org/wiki/Earth_or

    #EarthOrientationParameters #Earth #Geodesy #Astrometry

  10. Images of the lowest-mass extrasolar #planet ever discovered that has both a direct mass measurement and an orbit similar to the giant planets in our own solar system.

    It’s also among the first ever discovered using a technique called #astrometry, which relies on subtle movements of a host #star over many years.

    The planet is about three times the mass of #Jupiter orbiting AF Leporis, a young sun-like star about 87.5 light years away.

    #astronomy #exoplanets
    mcdonaldobservatory.org/news/r

  11. Long article on the combined #exoplanet hunting method from the previous post in the thread: expressnews.com/business/artic - the first author "says combining #astrometry and direct imaging strategies should lead to the discovery of more exoplanets — and he’s already been reviewing data from #Gaia and Hipparcos to get a bead on more catalogued stars with orbiting companions."

  12. @greggadams I suspected #Pixel7 was making a lot of these #stars up while losing many others in #computationalphotography #postprocessing cleanup, so I took the liberty of running your photo through an online #astrometry tool. Well, after giving it a decently thorough try of over 10 minutes, it failed to identify the part of the sky your photo shows nova.astrometry.net/status/699 I mean it's a nice looking photo, it just doesn't align particularly well with reality.

    One thing that bugged me the most with it is that it made all the stars the same colour and there's a sudden cutoff at a certain apparent magnitude of stars in the clearest portion of the sky where there should be more fainter stars visible than behind the clouds, and yet it's exactly the opposite in your photo.

    I'm attaching a quick test of a similar scene but using a "dumb" #Canon #R6 for comparison (just using a kit lens, wanted to see how well it'd do). Astrometry tool identified the #starfield in 50s nova.astrometry.net/status/699

    I guess we'll have to invent new branch of #ethics with "computational photography" just as we're overdue having one for #AI generated contents like #ChatGPT, #DALLE or similar. :breadthink: #FoodForThought

  13. Constraints for the orbital #inclination and the true mass of long-period single companions.

    This work illustrates how #Gaia and #Hipparcos allow for the orbital properties and masses of long-period RV companions to be further constrained.

    The first constraints for nearby long-period #planets from Gaia have started getting published.

    #astronomy #exoplanets #radialvelocity #astrometry
    arxiv.org/abs/2301.01263

  14. Stellar and substellar companions from Gaia EDR3.

    According to this new paper, #Gaia #astrometry sensitivity would be just enough to independently verify the existence of Proxima c.

    Although the existence is in serious doubt, Gaia could help resolve the situation by providing a clear detection or by ruling out the existence of the planet.

    #astronomy #exoplanets #Proximab

    Paper by Kervella et al (2022): arxiv.org/abs/2109.10912

  15. "HIP 99770 b is the first #exoplanet ever discovered jointly through direct imaging and #astrometry and the first discovery leveraging on μ-arcsecond precision #Gaia astrometry": arxiv.org/abs/2212.00034

  16. A detection of a superjovian #exoplanet around the dusty A star HIP 99770 using precision #astrometry and direct imaging.

    The #planet HIP 99770 b is in a low-eccentricity orbit 16.9 au from the primary, receiving about as much light as #Jupiter does from the Sun.

    This discovery is a proof-of-concept for a fundamentally new strategy for finding imageable planets: selecting targets based on dynamical evidence from indirect methods like astrometry.

    #astronomy #exoplanets arxiv.org/abs/2212.00034