A nice story in Nature Africa about MeerKAT observations of galaxy clusters, featuring Dakalo Phuravhathu - one of our PhD students at Wits 🔭 🇿🇦
www.nature.com/articles/d44...
New Publication at the Open Journal of Astrophysics: "The Atacama Cosmology Telescope: DR6 Sunyaev-Zel’dovich Selected Galaxy Clusters Catalog" by M. Aguena et al. (101 authors altogether), on behalf of the ACT-DES-HSC Collaboration
doi.org/10.33232/001...
✨ WITS O’WEEK VIBES! ✨
Our newest Witsies are exploring campus 🙌
Swing by the Wits Digital Dome (near the Empire Rd entrance)🌍💡
Experience immersive 360° storytelling, mind‑blowing visuals, and tech that sparks bold ideas. 🚀
🎟️ Student tickets: R45 on Webtickets
📍 Find us, experience the future today
🎉 We’re Back! 🎉
The Wits Digital Dome is OPEN for 2026
Kick off the year with mind-blowing experiences under the dome.
📅 First Public Show: Dark Universe |13 Jan | 17:00
Explore the mysteries of the cosmos in this breathtaking journey through space!
🌐 Public show lineup: digitaldome.wits.ac.za/shows
A Mercator map of the world with the countries outlined. The map is mostly white, but Greenland, Tibet, the Andean Plateau and Antarctica are colored in various shades of blue. The legend indicates this means lower amounts of precipitable water vapor. The color scale goes from 0 to 5, with antarcitca the closest to 0, Greenland , Chile and Tibet sit between 1 and 2.5
On the first day of CMBmas, the observatory
Had a low PWV
Telescopes like us are inconvenienced by water in the atmosphere emitting/blocking microwaves (same reason why a microwave heats food well). Luckily, the #Atacama desert has one of the lowest Precipitable Water Vapour amounts Earth.
The stars, planets, and everything you can see are less than 5 percent of the universe. "Dark Universe" explores the invisible 95% of our cosmos - dark matter and dark energy.
Shows from 16 Jan - 28 Feb, 2026.
Trailer: www.youtube.com/watch?v=KmN2...
Tickets: www.webtickets.co.za/v2/event.asp...
Nice new MeerKAT result - discovery of an ultra steep spectrum radio halo in a distant cluster. It seems that these objects light up in the radio following a cluster merger. Led by Isaac, a PhD student here at Wits.
South Africa is a global hub for astronomy 🌌
Experience Rising Star at the Wits Digital Dome - a planetarium film that journeys from our beginnings to the future of African astronomy, featuring SALT & MeerKAT. 🇿🇦✨
🎥 Made in Africa. For the world.
www.webtickets.co.za/v2/event.asp...
This includes astro folks, open to any area of physics/astrophysics. There is also a senior lecturer position open. Deadline for all is 17 Oct
UK people! If you tune in to BBC Four at 22:00 BST this Monday, you will see us on The Sky at Night! www.bbc.co.uk/programmes/m... (plus other features on @vrubinobs.bsky.social and DESI) #scicomm
I'm talking about the oldest light in the universe at the Digital Dome at Wits this coming Monday. We will attempt to combine a talk with getting some data from Atacama Cosmology Telescope + Planck onto the full dome! Plus some prettier optical/IR data. Will it work? Come along and find out!
COSMOSENO showcases immersive audiovisual work, reflecting the current socio-environmental crisis and calling for a human re-evaluation of our relationships with the Cosmos. Friday 1 August and Saturday 2 August from 10:00 - 12:00. Please book tickets free of charge
www.quicket.co.za/events/32567...
A glittering tapestry of thousands of galaxies in varying sizes, shapes, and colors. At center is a distinct collection of galaxies, all of a similar yellow color.
A glittering tapestry of thousands of galaxies in varying sizes, shapes, and colors. At center is a distinct collection of galaxies, all of a similar orange color.
A glittering tapestry of thousands of galaxies in varying sizes, shapes, and colors. At center is a distinct collection of galaxies, all of a similar red color.
NSF–DOE Rubin Observatory's view of the Virgo Cluster is full of galaxy clusters: collections of gravitationally-bound galaxies ✨ They can be identified as similarly colored smudges concentrated together.
Here, we can see three different clusters at different distances. #RubinFirstLook 🔭🧪
The Wits Anglo American Digital Dome has been honoured with a historic Blue Plaque by the Johannesburg Heritage Foundation, recognising its cultural, architectural, and academic significance as the former Johannesburg Planetarium
Read More: ow.ly/xzq450WkRLh
Today there is the first public release of images from Rubin Observatory, an amazing new optical telescope located in Chile. I hope all the people attending the first light events in South Africa (at @witsdigitaldome.bsky.social in Joburg and Iziko in Cape Town) have a good time!
Using data from the Southern African Large Telescope 🔭
Rubin Observatory under a green/yellow hued night sky and glowing vertical band of the Milky Way. Text reads "Six things to know about Rubin Observatory"
We are T–10 days from NSF–DOE Rubin Observatory's First Look! 🚨
This reveal of Rubin's first images is just a preview of what's to come as Rubin prepares to #CaptureTheCosmos for the next ten years! 🔭🧪
Here are 6 things you need to know before the big day🎬
🧵
Welcoming all astronomy enthusiasts for our interactive live shows from 3 July. In an hour, we will explore the southern sky gems, some of the less well-known southern sky constellations and deep-sky objects.
digitaldome.wits.ac.za/shows/
Tickets are online only
www.webtickets.co.za/event.aspx?i...
These are real images of exoplanets.
Four super-Jupiters, imaged 10 times over 12 years around a star 133 lightyears away.
These are real, giant worlds, out there in the dark.
And we can see them.
The first planetarium opened on May 7, 1925 in Munich. This May, we celebrate a century of wonder, discovery, and exploration with the show, '100 Years of Eternity', from early cultures and leading to the modern Digital Dome.
Tickets only on Web Tickets.
www.webtickets.co.za/v2/event.asp...
Around two dozen people sit and stand at a long desk with computer monitors out of view. Several people are smiling or have their mouths open in amazement. One person in the back has their arms raised in celebration.
Eye to the sky…on-sky engineering tests have begun at NSF–DOE Rubin Observatory using the world’s largest digital camera! 🔭🧪
After installing and testing the LSST Camera, we turned the telescope to the sky—a moment 20 years in the making!
With that, Rubin #CommissioningNotes are back ✍️
🧵
The Simons Observatory LAT with its aperture open, looking at the sky at night. Red safety lights illuminate the bottom of the telescope structure, while a few stars shine in the background.
This week, we are trying to assess performance of our Large Aperture Telescope by looking at the planet Mars. For our telescope, it appears as a point, so we can understand our optical response and pointing by observing it.
Image credit: Mark Devlin. ☄️🔭
The @simonsobservatory.org recently completed the installation of its Large Aperture Telescope, joining its three Small Aperture Telescopes. These telescopes will collect the most precise measurements yet of the universe’s oldest light. www.simonsfoundation.org/2025/03/17/s... #science #astronomy
Lights, camera, action!
The world's largest digital camera has been installed at NSF–DOE Rubin Observatory! 🤩
The LSST Camera was the final major component of the observatory. With it in place, Rubin officially enters its final phase of testing!🔭
🔗: rubinobservatory.org/news/lsst-camera-installed
A timeline of the LAT's status between 2020 and 2034. Construction lasts until 2025, the LAT gets upgraded sometimes in 2028, sensitivity raises with time to 2.5 microK/arcmin over 20000 square degrees. 3d renders show the LAT and the focal plane getting filled up
We have two preprints out on the arXiv today 🔭☄️!
The first one is about an #NSFFunded upgrade to our Large Aperture Telescope, roughly doubling the number of detectors in it: arxiv.org/abs/2503.00636 enabling us to probe the sky deeper than ever. The paper was led by Susan Clark and Colin Hill.
Just a couple of days to go until abstract submission closes for Cosmology on Safari 2025 #cosmology 🔭
One week to go until abstract submission closes
Something else to thank EM for.
"The sustained rate of daily reentries is unprecedented," says Jonathan McDowell, an astronomer at the Harvard Center for Astrophysics who tracks satellites. "They are retiring and incinerating about 4 or 5 Starlinks every day."
@planet4589.bsky.social
#astronomy
Cosmology on Safari is happening again (1-7 June 2025, Hluhluwe, KwaZulu-Natal, South Africa - cosmosafari.co.za). This will be our 5th such conference, and our 10th anniversary! Abstract submission closes Feb 25th #cosmology 🔭
I am so glad @rossandersen.bsky.social took the time to write this. It is a thorough and accurate summary of the @vrubinobs.bsky.social situation. I have MANY FEELINGS about each and every facet of said situation, let me tell you. This won't be the last you hear of "telescope vs crap in orbit" 🔭
