@bllalejandro

Astrophysicist. Interested in numerical cosmology, dark matter, galaxy formation. Computer graphics enthusiast. Assistant Professor at @unimib.

 Milan, Italy
alejandrobll.github.io
Joined September 2014
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  • Followers257
73Media
Nice to see our research featured by @NASA and @NASAHubble – at Monza, Lombardia
NASA
@NASAJan 5
A team using @NASAHubble has made the first confirmed detection of a new type of astronomical object: a starless, gas-rich, dark-matter cloud, nicknamed Cloud-9. Here's what this object is teaching us about dark matter and the early universe: go.nasa.gov/3YYPVqU
A magenta cloud is radio data representing the location of the dark-matter cloud. There is a yellow dashed-line circle roughly in the center of the image, marking where researchers focused their search for stars. There are some galaxies in the background; they are mostly located away from the magenta cloud. Credit: Image: NASA, ESA. G. Anand (STScI), and A. Benitez-Llambay (Univ. of Milan-Bicocca); Image processing: J. DePasquale (STScI)

ALT A magenta cloud is radio data representing the location of the dark-matter cloud. There is a yellow dashed-line circle roughly in the center of the image, marking where researchers focused their search for stars. There are some galaxies in the background; they are mostly located away from the magenta cloud. Credit: Image: NASA, ESA. G. Anand (STScI), and A. Benitez-Llambay (Univ. of Milan-Bicocca); Image processing: J. DePasquale (STScI)

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Alejandro Benítez-Llambay retweeted
Scientific American
@sciamApr 27
The galaxy, also known as Messier 104, gets its nickname from its central bulge and outer dust trail, which gives it a sombrero-like appearance from our vantage point spklr.io/6019EK9QU

Iconic Sombrero Galaxy captured in incredible detail, revealing its enormous glowing halo

This galaxy, also known as Messier 104, gets its nickname from its central bulge and outer dust trail, which give it a sombrerolike appearance from our vantage point

scientificamerican.com
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py-sphviewer 2.0 is now live on GitHub. Rebuilt with a novel super fast algorithm. Native C++ multithreading. Native rotations and panning. Deferred Rendering, and more. Is it worth a try? Ask Grok 😉 Source, Intallation & Tutorials here: github.com/alejandrobll/py-s…
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Alejandro Benítez-Llambay retweeted
Hugh Ross
@RTB_HRossMar 9
Astronomers confirm a major prediction of the big bang creation model where dark energy is the universe's dominant component & cold dark matter is the 2nd most abundant component. They found a starless massive gas cloud in M94's halo. The hydrogen gas in this cloud has a mass equal to a million Suns, has a 9,000 light-year diameter, & contains no luminous stars, implying that it is relic gas cloud left over from the cosmic creation event. You can read about the discovery here: iopscience.iop.org/article/1…

The First RELHIC? Cloud-9 is a Starless Gas Cloud

The First RELHIC? Cloud-9 is a Starless Gas Cloud* , Anand, Gagandeep S., Benítez-Llambay, Alejandro, Beaton, Rachael, Fox, Andrew J., Navarro, Julio F., D’Onghia, Elena

iopscience.iop.org
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Alejandro Benítez-Llambay retweeted
Space Telescope Science Institute@SpaceTelescopeFeb 4
If you've ever wondered what Hubble and Webb were observing at any time? 👀 Space Telescope Live can show you what the telescopes are looking at now and what the next planned observation will be, all in one space (pun intended 😁): spacetelescopelive.org/
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I had a wonderful interview for Our Narratives, a platform dedicated to sharing original stories, artwork, and research. It was a pleasure to be part of this experience. You can read the interview here: ournarratives.net/cloud-9-th… – at Brugherio, Lombardia
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Gracias a Alejandro Horvat y a @LANACION por esta nota científica sobre nuestro trabajo!
LA NACION
@LANACIONJan 12
Cloud-9: un investigador argentino lideró el hallazgo con el telescopio Hubble de una estructura cósmica jamás observada lanacion.com.ar/sociedad/clo…
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Another excellent write-up of our results via @SkyandTelescope. Arielle Frommer did a fantastic job summarizing the physics at play and properly contextualizing the alternative interpretations we explored.
Sky & Telescope@SkyandTelescopeJan 8
Astronomers discovered a cloud of hydrogen gas that’s devoid of stars. Held together by an invisible halo of dark matter, the starless cloud may elucidate its nature. Read more: buff.ly/43T3txm
Cloud 9

ALT Cloud 9

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Alejandro Benítez-Llambay retweeted
Space Telescope Science Institute@SpaceTelescopeJan 5
Scientists trained Hubble’s sharp vision on a starless, gas-rich, dark-matter cloud and identified a new type of astronomical object—a failed galaxy that never produced stars. Nicknamed Cloud-9, it is considered a fossil from the early universe: news.stsci.edu/4bdj2Ov #AAS247
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NEW from #AAS247: NSF NRAO Radio Telescopes Help Reveal Cloud-9, a Starless Dark-Matter “Failed Galaxy” Near M94 public.nrao.edu/news/starles… 📸 Credit: NASA, ESA, NSF VLA, Gagandeep Anand (STScI), Alejandro Benitez-Llambay (University of Milano-Bicocca), Joseph DePasquale (STScI)

NSF NRAO Radio Telescopes Help Reveal Cloud-9, a Starless Dark-Matter “Failed Galaxy” Near M94

Astronomers using NSF’s VLA and GBT, along with NASA’s Hubble Space Telescope, have confirmed Cloud-9 near M94 as a starless, dark-matter–dominated gas cloud—offering rare evidence for long-predicted...

public.nrao.edu
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Pablo Benitez Llambay@pabllam9 Oct 2025
Our new paper with @ximexram on a comoving framework for planet migration is on arXiv! Simulating planets moving through their disk is computationally expensive. Our new method solves this by keeping the planet fixed, making simulations over >10x faster!
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Pablo Benitez Llambay@pabllam23 Sep 2025
From preprint to final publication! The journey for this review on planet-disk interaction is complete. The officially published version is now available online. I hope it serves as a useful resource for the community! Published version: doi.org/10.1016/B978-0-443-2…
Pablo Benitez Llambay@pabllam2 Oct 2024
Preprint of my review chapter on planet-disk interactions for the upcoming Encyclopedia of Astrophysics is on arXiv. It provides a first solid approach into planet-disk interactions for both undergraduate students and researchers from other fields. arxiv.org/abs/2410.00374
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Our new @NASAHubble observations of Cloud-9, an HI cloud near M94, find no galaxy with mass > 3,000 solar masses, making it the strongest candidate yet for a starless dark matter halo, long predicted, but never observed! Exciting! arxiv.org/abs/2508.20157
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Gracias por divulgar ciencia y en particular nuestra investigación @doctorfision – at Monza, Lombardia
Doctor Fisión
@doctorfision12 Aug 2025
¿Es esta la primera imagen de la red cósmica, la colosal telaraña invisible que sostiene al universo? En ella, las galaxias no flotan al azar, sino que se agrupan y conectan a lo largo de filamentos de gas que atraviesan el cosmos como hilos de luz.
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Alejandro Benítez-Llambay retweeted
William (Will) Cerny@wcerny_astro5 Aug 2025
Interested in helping find new Milky Way satellite galaxies? Join "DELVE Dwarf Galaxy Quest: Milky Way Neighbors" on Zooniverse to classify potential candidates! zooniverse.org/projects/ywyh…

DELVE Dwarf Galaxy Quest: Milky Way Neighbors | Zooniverse - People-powered research

Discovering New Milky Way Dwarf Galaxies with New Image Data

zooniverse.org
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Aston Martin testing in Monza today. Will they deliver the top speed Alonso needs? #Formula1 #monza – at Arcore, Lombardia
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Alejandro Benítez-Llambay retweeted
AAS Press Office@AAS_Press27 May 2025
University of Chicago: Possible Sign of Life in Deep Space Faces New Doubts news.uchicago.edu/story/poss…

Possible sign of life in deep space faces new doubts

UChicago analysis of new and old data suggests the signal is weak and explainable by other molecules

news.uchicago.edu
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This month’s Nature Astronomy cover features our recent paper led by Davide Tornotti, in which we image a filament connecting 2 QSOs. The cover was created in seconds using our new py-sphviewer 2.0 code, which renders N-body simulations with unprecedented spatial dynamic range.
Nature Astronomy@NatureAstronomy25 Apr 2025
Our April issue is now available to read! The cover image shows the (simulated) filaments of the cosmic web, and comes courtesy of the Tornotti et al. paper within the issue: nature.com/natastron/volumes…
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scientificamerican.com/artic… – at Monza, Lombardia

Frozen Cosmic Sound Bubbles Suggest Dark Energy Is Shockingly Changeable

A new map of cosmic expansion suggests that dark energy evolves over time, hinting that the universe doesn’t work the way we thought it did

scientificamerican.com
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Proud of the first paper led by Davide Tornotti, which is now published in Nature! nature.com/articles/s41550-0…. Keep up the excellent work! – at Milan, Lombardy

High-definition imaging of a filamentary connection between a close quasar pair at z = 3

Nature Astronomy - Deep optical imaging of a close quasar pair reveals a filamentary connection between them, providing insight into the transition between intergalactic and circumstellar media and...

nature.com
Università degli Studi di Milano-Bicocca@unimib30 Jan 2025
Ottenute le prime immagini del filamento cosmico che unisce due galassie in formazione, risalente a quando l’#Universo aveva solo 2 miliardi di anni 🔭 La scoperta apre una nuova prospettiva per comprendere l'essenza della materia oscura 🪐 @INAF_astro unimib.it/comunicati/ragnate…

La “ragnatela cosmica” della materia oscura che forma l'Universo fotografata da ricercatori di...

unimib.it
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