Astronomers track bubbles on a star’s surface in the most detailed video yet

For the first time, astronomers have captured images of a star other than the Sun in enough detail to track the motion of bubbling gas on its surface. The images of the star, R Doradus, were obtained with the Atacama Large Millimeter/submillimeter Array (ALMA), in July and August 2023. They show giant, hot bubbles of gas, 75 times the size of the Sun, appearing on the surface and sinking back into the star’s interior faster than expected.

This research was presented in the paper One month convection timescale on the surface of a giant evolved star (DOI) published on 11 September 2024 on Nature.

Read the ALMA press release here and the ESO press release here.

Image: © ALMA (ESO/NAOJ/NRAO)/W. Vlemmings et al.; Astronomers have captured a sequence of images of a star other than the Sun in enough detail to track the motion of bubbling gas on its surface. The images of the star, R Doradus, were obtained with the Atacama Large Millimeter/submillimeter Array (ALMA), a telescope co-owned by ESO, in July and August 2023. This panel shows three of these real images, taken with ALMA on 18 July, 27 July and 2 August 2023. The giant bubbles — 75 times the size of the Sun — seen on the star’s surface are the result of convection motions inside the star. The size of the Earth’s orbit is shown for scale.

The MeerKAT Absorption Line Survey: A million radio sources probe the motion of the solar system and provide a fundamental test of cosmology

Using data from the MeerKAT radio telescope, an international team of astronomers from the MeerKAT Absorption Line Survey (MALS) collaboration have compiled the largest catalog of radio sources from any MeerKAT survey to date. With this catalog, they were able to make a measurement of the cosmic radio dipole, a cosmological effect that arises from the Earth’s motion through the Universe, and provides an important test of our theories of cosmology at the largest scales. This new measurement demonstrates the value of the sensitive MeerKAT data, and shows that such deep data provide extremely valuable insights into the origin of the cosmic dipole effect.
The results are published in Astronomy & Astrophysics: The MeerKAT Absorption Line Survey Data Release 2: Wideband continuum catalogues and a measurement of the cosmic radio dipole (DOI).

Read more here.

Image: © MALS Team; A map of the sky overlaid on a portion of single MeerKAT pointings containing a few thousand radio sources. In the sky map, circles mark positions of 391 pointings containing a total of 971,980 sources. The arrow shows the direction of the cosmic dipole originally established by measurements of the cosmic microwave background radiation. The dipole effect will make the sources appear more numerous (red portion) in the direction of the motion and less numerous in the opposite direction (blue portion).

INAF: Open Call

The call for proposal for observing with the INAF telescopes is open. See here.

INAF participates with the Sardinia Telescope (SRT)  in the Transnational Access program of the Opticon Radionet Pilot program (ORP), which is funded by the EC Horizon 2020 Research and Innovation Programme under grant agreement No. 101004719. For observations with the STR telescope, access/funding can be offered through the ORP project.

Submission deadline 14. October 2024 at 12:00 UTC

Open e-Merlin Call – Cycle 19

The e-Merlin call for proposals for Cycle 19 is now open. Read the call here.

Please use the e-MERLIN proposal tool to submit your proposal.

Access/funding is offered through the ORP (Opticon RadioNet Pilot) project.

Submission deadline: 24 October 2024, 13:59 UT

Open call for the East Asian VLBI Network (EAVN)

Call for Proposals for the EAVN for the 2025A semester is open.

Submission deadline: 1 November 2024, 8:00 UT

Image: © KASI  

European ALMA Regional Centre

The European ALMA Regional Centre (ARC) provides the interface between the ALMA project and the European science community. The ARC is staffed by scientists with expertise in radio astronomy and interferometry and it supports its users throughout the lifetime of a project, from proposal preparation to data analysis. Users that want to visit an ARC node for a face-to-face visit can apply for funding through the ORP project. 

Westerbork Apertif Long Term Archive

ALTA offers to the world-wide astronomical community free virtual access to data and scientific products produced from all sky surveys of the Northern sky that will be conducted with the new Apertif frontend of the Westerbork Synthesis Radio Telescope (WSRT), as well as tools to query, further exploit and perform data mining of these products adaptable to diverse research goals. The access/funding offered through the ORP project.

LOFAR Long Term Archive

LTA is a long-established archive and access facility supporting the international LOFAR telescope. It is currently the largest radio astronomical archive in the world already exceeding 45 PB from LOFAR’s past 10 years of operations. The LTA provides a central and key resource for all observed LOFAR astronomical science programs where the data become public within 12 months of first creation. The access/funding is offered through the ORP project.