This gorgeous star trail image, captured by Chilean astrophotographer Osvaldo Castillo at our Paranal Observatory, is today's Astronomy Picture of the Day! 🥳

apod.nasa.gov/apod/ap260828.ht…

#astrodon #astronomy #astrophotography #astrophysics #space #science

ESO

2025-11-17 08:00:02

A hypnotising view of Paranal in #Chile!

Yet the sky is not revolving around the tip of one of our Auxiliary Telescopes. This illusion is caused by the almost perfect alignment with the southern celestial pole, around which stars seem to trail due to Earth's rotation.

Capturing these circular star trails is no easy task: a slight misalignment can completely ruin the outcome! 😲

Read more: eso.org/public/images/potw2546…

📷 O. Castillo/ESO

#astrodon #astronomy #astrophysics #space #science

A hypnotising view of Paranal

^www.eso.org

A bubbling Betelgeuse ⭐️ 🫧

Taken with ALMA, this is one of the most detailed views yet of the surface of the iconic star Betelgeuse.

The star's surface is uneven and lumpy, with peaks and troughs originating from giant bubbles of hot gas rising from deep within the star to its surface.

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📷 ALMA(ESO/NAOJ/NRAO)/W. Dent et al.

#astrodon #astronomy #astrophysics #space #science

You might have noticed our new header picture and that we didn't explain it yet. 😃 Let's do this now! It shows from the left to the right:

– details of the ETpathfinder laser source developed and built at the institute,
– a view of the optical table in the central tank of the institute's 10 meter prototype,
– an optical simulation of laser beams in that 10 meter prototype using the software IfoCAD, developed at our institute.

All three projects are used to develop key technologies for the Einstein Telescope. The @bmftr_bund is funding this effort with about 4.3 million euros over the next three years.

ℹ️ aei.mpg.de/1483931/mehr-als-4-…

#EinsteinTelescope #ET #ETpathfinder #physics #researchfunding #astrophysics

This made me very happy to read: An #asteroid has been named after Susanne Pfalzner.

I attended her lectures on #ComputationalAstrophysics and #StarFormation during my studies, and she later served as the 2nd examiner for my Master’s thesis. She is an outstanding scientist and lecturer, and this is such a well-deserved honor. My warmest congratulations to her! 👏👏👏

🌍 fz-juelich.de/en/jsc/news/news…

#Astronomy #Astrophysics #Physics #SpacePhysics 🌌

I'm not convinced that the name ever took off beyond those people who coined it for a paper.

Whereas Hayford Peirce wrote a novel about a Black Hole Planet.

#astrophysics #SciFi #astronomy #HayfordPeirce

One for the record books 🏅

Our Very Large Telescope Interferometer has discovered the fastest known star in our galaxy. Named S301, it orbits Sagittarius A* — the supermassive black hole at the centre of the Milky Way — reaching speeds of 25 000 kilometres per second, over 8% the speed of light.

📷 ESO/GRAVITY collaboration

1/3

#astrodon #astronomy #astrophysics #space #science

More than 4 million euros for the development of the Einstein Telescope

👏 Researchers at the Institute for Gravitational Physics at @unihannover and at the @mpi_grav together with the Laser Zentrum Hannover e.V. (LZH) and other partner institutions in Germany, have successfully secured funding for several projects as part of the Einstein Telescope preparatory program.

📈 Over the next three years, a total of approximately 4.3 million euros from the @bmftr_bund is available for work at the institutes.

🔑 As part of the funded projects, key technologies for the Einstein Telescope are to be developed in Hannover. These technologies are necessary for the planned third-generation observatory to achieve its target sensitivity.

ℹ️ aei.mpg.de/1483931/mehr-als-4-…

Image: NIKHEF

#EinsteinTelescope #ET #Physics #ResearchFunding #Astrophysics

A giant made of many 📡

These are just a few of the 66 antennas that make up the international observatory ALMA, in which ESO is a partner.

They work together rather than as separate telescopes, allowing astronomers to study some of the coldest material in the Universe — including clouds of gas and dust where stars are born and discs where planets take shape — in great detail.

Find out how: eso.org/public/images/potw2633…

📷 A. Russell/ESO

#astrodon #astronomy #astrophysics #space #science

The night shift begins.

At our Paranal Observatory, sunset does not mark the end of the day: it signals the beginning of a night under the stars.

Taken after dinner, before heading to the telescopes for a night of observing, this image shows the last rays of sunlight slicing through one of the corridors at the Residencia — a home away from home for astronomers and other staff members.

eso.org/public/images/potw2632…

📷 L. Sbordone/ESO

#astrodon #astronomy #astrophysics #space #science #architecture

Earlier today, the discarded upper stage of a Falcon 9 rocket impacted on the Moon. As part of a coordinated observing campaign, our Very Large Telescope detected spectral lines of sodium and lithium gas in the impact plume lasting for 5-10 minutes after impact.

📷 ESO/C. Schmidt et al.

1/4

#astrodon #astronomy #astrophysics #space #science

Total solar #eclipse loading ☀️🌕🌍

On 12 August, the #Moon will slip between the #Earth and the #Sun, turning day into night for up to a minute and a half along the path of totality.

Get the gist with ESO fellow Mar Carretero Castrillo 🎬👇

1/4

#astrodon #astronomy #astrophysics #space #science #solareclipse

Unusual asteroid unmasked! 🪨

Using our VLT in Chile & the Large Binocular Telescope in the US, astronomers have resolved the shape of (44) Nysa, a peculiar asteroid between Mars and Jupiter.

They revealed a structure unlike anything observed before!

📹 ESO/K. Minker et al.
1/2

#astrodon #astronomy #astrophysics #space #science

Astrophysical jets are associated with many types of high-energy astronomical sources, such as black holes, neutron stars and pulsars. Their causes are not yet fully understood, but they are believed to arise from dynamic interactions within accretion disks. One explanation is that as an accretion disk spins, it generates a rotating, tangled magnetic field which concentrates material from the disk into the jets and then

en.wikipedia.org/wiki/Astrophy…

#void #astrophysics #caturday #caturdayeveryday

The conclusion of a century-long quest 😲

Our VLT obtained firm evidence that Betelgeuse, a red supergiant star in the Orion constellation and one of the most famous stars in the night sky, is not alone!

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📷 ESO/M. Montargès et al. Background: N. Rissinger (skysurvey.org)

#astrodon #astronomy #astrophysics #space #science

How do stars function and age? How far away are galaxies? How fast and why is the Universe is expanding?

Welcome to Professor Richard I. Anderson whose research looks at these questions! Thanks to a Lower Saxony Impulse Professorship, the astrophysicist takes up the Chair in Observational Cosmology. He’ll establish an innovative research programme at the interface between stellar #astrophysics and observational #cosmology.

This research works towards resolving the still unexplained discrepancy in determining the #Hubble constant, known as the “Hubble tension”: uni-goettingen.de/en/3240.html…

A gateway to the Milky Way?

This road sign marks the entrance to ALMA, in #Chile 's Atacama Desert. ALMA studies light from the coldest corners of the Universe. But this radiation is absorbed by water vapour in Earth’s atmosphere. This is why ALMA is located in one of the driest and highest places on Earth, on the Chajnantor Plateau in the Andes, at an impressive altitude of 5000 metres.

Read more: eso.org/public/images/potw2626…

📷 J. Looten/ESO

#astrodon #astronomy #astrophysics #space #science

📣 New title image 🖼️

The image shows results from computer simulations of neutron star mergers at five different times (from less then 2 to about 120 milliseconds) after the merger. Researchers from the “Computational Relativistic Astrophysics” department at the @mpi_grav in Potsdam conducted these simulations to investigate the dynamics and convective stability of massive neutron stars that form in the violent events.

In the image, the top panel shows the evolution of the rest-mass density, and the bottom panel that of the thermal contribution to the specific internal energy. The image is from Fig. 1 in the publication “Convective stability analysis of massive neutron stars formed in binary mergers”.

➡️ journals.aps.org/prd/abstract/… [Open Access publication]

#NeutronStar #Astrophysics #GravitationalWaves #Astronomy #Astrodon

Our ears are burning – gravitational waves in today's xkcd 😀

xkcd.com/3261/

@LIGO

#GravitationalWaves #xkcd #Physics #Astrophysics #Science #Research

Starter packs for geosciences, astronomy and physics (partly Germany-centric):

Earth and Geoscience: fedidevs.com/s/OTk1/ by @pikarl

Astronomy and Space: fedidevs.com/s/NjA2/

Physics: fedidevs.com/s/ODg2/

As I find I am running into limits with pinned posts, I've decided to consolidate three starter packs I like to recommend into this one single post. Enjoy!

#FollowFriday #StarterPacks #Science #Physics #Astrodon #Astronomy #Astrophysics #Geosciences #Geology #EarthSciences #PlanetaryScience

📣 New title image 🖼️

The image shows the spectrograms of all loud gravitational-wave events from the observing run O4b, which are listed in the new GWTC-5.0 catalog.

Researchers at the @mpi_grav contribute to discoveries in the largest gravitational-wave catalog ever compiled.

➡️ aei.mpg.de/1449649/the-new-lig

GWTC-5 is the largest gravitational-wave catalog, with 161 new events, totaling 390 confirmed detections since 2015.

Picture: Derek Davis / University of Rhode Island / LIGO-Virgo-KAGRA

#GWTC5 #GravitationalWaves #BlackHoles #Astrophysics #Astrodon #Astronomy

The new LIGO-Virgo-KAGRA catalog sets records in precision gravitational-wave astronomy – Researchers at the @mpi_grav contribute to discoveries in the largest gravitational-wave catalog ever compiled.

➡️ aei.mpg.de/1449649/the-new-lig…

The @LIGO Virgo KAGRA collaboration releases the largest gravitational-wave catalog, GWTC-5, with 161 new events, totaling 390 confirmed detections since 2015.

The catalog contains many astrophysical highlights: the gravitational-wave source with the most precise sky localization, the first measurement of three gravitational-wave tones from a black hole, evidence for the existence of second-generation black holes, and new measurements of how fast the Universe is expanding.

Picture: Derek Davis / University of Rhode Island / LIGO-Virgo-KAGRA

#GWTC5 #GravitationalWaves #BlackHoles #Astrophysics #Astrodon #Astronomy

📣 New title image 🖼️

The diagram shows results from a numerical relativistic computer simulation of merging neutron stars.

The new simulation takes into account muons and their reactions to get a physically more complete picture of what happens in these extreme cosmic events.

Researchers at @unipotsdam, at Universidade Federal do ABC in Brazil, and at @mpi_grav have recently published their results: arxiv.org/abs/2604.14225.

The diagram from that manuscript shows the muon fraction and its deviation from equilibrium at different times after merger.

The most important finding: Unlike reported in the literature so far, taking into account muons and their reactions only plays a minor role – at least in the context of calculating the synthesis of elements in neutron star mergers and their optical counterparts observable with telescopes.

#Astrodon #Astrophysics #Muons #NeutronStar

Spannende Sache. Dass Markarian 501 eventuell ein binäres supermassereiches Schwarzes Loch im Zentrum hat, wurde schon 2003 von Rieger und Mannheim vorgeschlagen.
ui.adsabs.harvard.edu/abs/2003…

#SMBH #Astrophysics #Mrk501 #AGN

📣 New title picture 🖼️

The diagram shows the results from the most sensitive search for continuous gravitational waves to date.

Researchers at @mpi_grav have used the computing power donated by tens of thousands of volunteers to @einsteinathome to search for the weak and yet to be detected signals deeper than ever before in @LIGO data.

They were the first to find all hardware injections (signals artificially added to the data by moving the LIGO mirrors).

Because computing power and efficiency are key, the team expects their results to be competitive with unpublished results by LIGO researchers based on O4 data, which is not yet publicly available.

ℹ️ aei.mpg.de/1403593/einstein-ho…

#CitizenScience #physics #astrophysics #astrodon #astronomy #GravitationalWaves

Posting in the Fediverse since last week: @uksolarphysics! 🇬🇧 ☀️

The UK Solar Physics community (UKSP) is a Specialist Scientific Group affiliated to the Royal Astronomical Society. They regularly provide relevant news and nuggets both to their members as well as the international solar physics community at large via uksolphys.org/

If you're interested in the research of the Sun, our closest star, at all, consider following them for their announcements either at uksolphys.org/news/recent-news…, or via their UKSP newsletter (mailing list), or now directly here via their Mastodon account @uksolarphysics

Maybe don't expect them to interact a lot, but if you *are* here for their very useful announcements, it is now really easy to follow and also boost those. So, a warm welcome to @uksolarphysics 🌞

#introduction #solarphysics #heliophysics #spaceweather #uksolarphysics #uksp #ukspnewsletter #royalastronomicalsociety #ras #sun #space #physics #fediverse #astrophysics #astrodon #neuhier

Typisches Aprilwetter: Erst dicht bewölkt und ziemlich unbeständig 🌧️
Doch am Ende hat die Sonne sich noch gezeigt – und wir konnten sogar mit den Teleskopen beobachten 🔭
Dazu gab es einige spannende Stationen und gut gefüllte Vorträge – danke fürs Vorbeikommen!❤️

#AstronomyDay2026 #Astronomietag #Astronomy #Astrophysics #MPIfR #RadioAstronomy #Stargazing #Telescope #ScienceOutreach #OpenDay #ScienceCommunication

“A Search for a Supermassive Black Hole Binary” – recent AAS Nova article about a paper by Jacob Cardinal Tremblay et al.

Jacob is a PhD student at @mpi_grav Hannover in the “Pulsar Timing Arrays” research group of the “Observational Relativity and Cosmology” department.

Article ➡️ aasnova.org/2026/03/18/a-searc…

Paper ➡️ doi.org/10.3847/2041-8213/ae3c…

#PulsarTimingArrays #PTAs #GravitationalWaves #Research #Physics #Astrophysics

Entdeckt unsere neue Pressemitteilung!

Check out our new press release!

➡️ mpifr-bonn.mpg.de/pressemeldun…

#Astrophysik #Radioastronomie #Pulsare #MPIfR #Wissenschaft #Universe #Cosmos #Entdeckung #Astronomy #RadioAstronomy #Pulsars #MPIfR #Science #Space #Cosmos #Astrophysics

New leadership team to guide the Einstein Telescope Collaboration – Change at a defining moment for gravitational-wave science

The international Einstein Telescope (ET) Collaboration announces a change in its scientific leadership, as a new spokesperson team takes office on 23 March 2026. Michele Maggiore and Angélique Lartaux will serve jointly as spokesperson and deputy spokesperson.

ℹ️ aei.mpg.de/1431966/new-leaders…

Picture: Marco Kraan/Nikhef

#EinsteinTelescope #GravitationalWaves #Research #Astrophysics

The GEO600 project will end on 31 December 2026

The gravitational-wave detector GEO600 south of Hanover, Germany, will cease operation at the end of 2026. The last Open Day will take place this summer. Group tours will be offered until the end of the year. In early 2027, dismantling of the facility will begin.

@maxplanckgesellschaft director Karsten Danzmann will retire on 31 March 2026. As a consequence, funding for the GEO600 project will terminate at the end of the year.

GEO600 is a beacon of international research. Technologies developed and tested in the GEO project are now used in all major gravitational-wave detectors around the world. The findings and experience gained also play a role in preparing future observatories such as the Einstein Telescope and the Cosmic Explorer.

ℹ️ geo600.org/240777/das-geo600-p…

#GravitationalWaves #Physics #Astrophysics #Research #GEO600

This image reveals the stars and gas surrounding the supermassive black hole at the Milky Way centre.

Now, using our Very Large Telescope, MPE astronomers discovered a new gas cloud orbiting the black hole, solving a puzzling question.

More: eso.org/public/images/potw2610…

📷 ESO/D. Ribeiro for the MPE GC team

#astrodon #astronomy #astrophysics #space #science

📣 New gravitational-wave catalog doubles number of detections 📈

The latest catalog of LIGO-Virgo-KAGRA gravitational-wave detections, GWTC-4, has been published. It presents 128 new candidates from the fourth observing run, more than doubling the previous total.

This catalog update results from a nine-month observing period (May 2023 to January 2024) of the gravitational-wave observatories.

Researchers at the @mpi_grav and at @unihannover have made significant contributions to this milestone, presented in several publications in a special issue of Astrophysical Journal Letters.

ℹ️ aei.mpg.de/1415736/new-catalog…

📄 iopscience.iop.org/article/10.… (OpenAccess)

#GravitationalWaves #GWTC4 #BlackHoles #Astrophysics #Astronomy #Science #Research

✨ New selected research highlight ✨

🔎 @einsteinathome's close look at the central compact objects in three supernova remnants.

@maxplanckgesellschaft researchers from the permanent independent research group “Continuous Gravitational Waves” at the @mpi_grav have published results from targeted searches for continuous gravitational waves from three young supernova remnants using public @LIGO data.

The computing power of the volunteer distributed computing project @einsteinathome made this possible.

No detection was made and these results provide the most stringent constraints on the ellipticity, r-mode amplitude, and, for the first time ever, crustal anisotropy of the stellar remnants.

One signal candidate remains after follow-up investigations of three independent data sets. Whether it is of astrophysical origin can only be decided by analyzing additional data not yet publicly available.

ℹ️ aei.mpg.de/1404141/probing-thr…

📄 arxiv.org/abs/2512.15672

#GravitationalWaves #Astrophysics

Our international summer #internship for senior high school students and recent high school graduates will take place 20 July to 7 August this year. Apply now - deadline is 15 March!

haus-der-astronomie.de/en/what…

#Astronomy #Astrophysics

New method could reveal hidden supermassive black hole binaries: Bright flashes of lensed starlight guide the way

➡️ aei.mpg.de/1407139/new-method-…

📄 journals.aps.org/prl/abstract/… (Open Access)

Researchers at Oxford University and the @mpi_grav in the Potsdam Science Park propose a new way to detect supermassive black hole binaries using gravitational lensing.

Black holes act as natural telescopes, bending light with their gravity. This creates bright images of stars from the same galaxy that lie behind the supermassive black hole binary.

As the binary orbits, it produces repeating flashes of lensed starlight. Wide-field sky surveys may detect these bursts in the future. These bursts can provide information about the black holes’ properties and enabling entirely new studies.

#BlackHoles #astronomy #research #science #GravitationalLens #astrophysics

1/2 AES Andes announced that it will step back from the megaproject INNA, planned to be located near our Paranal Observatory.

We welcome this announcement and expect that the project will be withdrawn from #Chile 's Environmental Assessment Service (SEA) soon, which would formally confirm INNA is not going ahead.

eso.org/public/news/eso2602/

📷 A. Ghizzi Panizza/ESO

#astrodon #astronomy #astrophysics #environment #space #science

📢🆕🚨 Using new data from the Event Horizon Telescope @‌ehtelescope, researchers have uncovered an important clue: they identified the most likely origin of the powerful outflow of matter (the jet) in the galaxy Messier 87 🌀.
🔭 The observations provide fascinating insights into the immediate surroundings of the extremely massive black hole 🕳️ at the center of the galaxy. Differences in the observed radio emission suggest that the jet forms very close to the black hole — in a region that had remained hidden in previous observations. Detailed modeling then allowed the position of the jet base to be narrowed down.
🕳️ Black holes themselves are invisible — but their surroundings reveal their secrets!

🆕 👉️ mpifr-bonn.mpg.de/pressrelease…

@nasa @esa
#BlackHole #EventHorizonTelescope #M87 #Astrophysics #RadioAstronomy #Jet #SpaceScience #Universe #Science #Astronomy #MPIfR

📢🆕🚨 Mit neuen Daten des Event Horizon Telescope @ehtelescope haben Forscherinnen und Forscher einen wichtigen Hinweis gefunden: Sie konnten den wahrscheinlichsten Ursprungsort des gewaltigen Materieausflusses (Jets) in der Galaxie Messier 87 🌀 bestimmen.
🔭 Die Beobachtungen geben spannende Einblicke in die unmittelbare Umgebung des extrem massereichen Schwarzen Lochs 🕳️ im Zentrum der Galaxie. Unterschiede in der gemessenen Radiostrahlung deuten darauf hin, dass sich der Jet sehr nahe am Schwarzen Loch bildet – und zwar in einem Bereich, der bei bisherigen Messungen unentdeckt geblieben war. Mithilfe detaillierter Modelle konnte schließlich die Position der Jet-Basis eingegrenzt werden.
🕳️Schwarze Löcher sind unsichtbar – aber ihre Umgebung verrät ihre Geheimnisse!

🆕 👉 mpifr-bonn.mpg.de/pressemeldun…

@nasa @esa
#BlackHole #EventHorizonTelescope #M87 #Astrophysics #RadioAstronomy #Jet #SpaceScience #Universe #Science #Astronomy #MPIfR

1/2 Young or old? There’s both in this image!

The main object depicted here is known as Ve 7–27. It was long believed to be a planetary nebula — namely, the end phase of a sun-like star’s life. Yet ESO's Very Large Telescope (VLT) has shown it to actually be a still-forming baby star.

But there's also a dead star lurking just nearby, so keep reading!

eso.org/public/images/potw2604…

📷 ESO/J. Suherli et al.

#astrodon #astronomy #astrophysics #space #science