South Pole Telescope

SPT observing last week (picture by SPT winterover Michel!) Less than 2-weeks away from #sunset at the #southpole, with the Sun about 5 degrees above the horizon. The sky is dry & clear enough in summer that we continue to take science observations ! @NSF @doescience

Even though @NSF #southpole station "officially" closed for winter, last week 2 final twin otter flights stopovered at Pole before heading North! They mainly serve other bases on station, wrapping up work a couple weeks after the last LC130s. Pic by Anjali. #Antarctica

One of the annual #southpole traditions at the start of winter is watching John Carpenter's #thething in the gym. A fitting start to over 8 months of isolation for the 40 winterovers after becoming officially stranded at a remote Antarctic base! #Antarctica

"Last flight" of the official #southpole Austral summer has taken off and winter has begun! SPT is now in charge of the capable hands of Wwinterovers Anjali and Michel for the next 8.5 months! Pic by Anjali . @NSF @doescience #Antarctica #WinterOlympicGames

New SPT-3G paper and data release! "SPT-3G D1: Compton-y maps using data from the SPT-3G and Planck surveys" @doescience @NSF arxiv.org/abs/2602.11279 #Antarctica #southpole

New SPT-3G paper! "Measurement of the Full Shape of the Thermal Sunyaev-Zel’dovich Power Spectrum from South Pole Telescope and Herschel-SPIRE Observations" that finds the "tSZ power spectrum measured at 9.3σ in both MV and CIB-min maps." arxiv.org/pdf/2602.10107 @NSF #southpole

Last week, the South Pole celebrated a wedding! This marks the fourth time in recorded station history for a couple to be married at the #southpole. Pic by SPT winterover Michel. #Antarctica #wedding @NSF

Last week a contingent of @NSF representatives and six US Senators from @SenateCommerce @commercedems visited the #southpole, getting a tour of the science on station, including SPT's very own Sasha Rahlin and Winterover Anjali Sehrawat! @doescience

"First constraints on causal sources of primordial gravitational waves from CMB B-mode data" SPT-3G helps break degeneracies between Inflationary, lensing, and causal sources of B-modes to provide first constraints! #southpole @doescience @NSF arxiv.org/abs/2601.20958

New SPT-3G constraints on CMB secondary anisotropies, including the thermal and kinematic SZ effect! "At ℓ=3000, we find thermal SZ power at 143 GHz of DtSZ=4.91±0.37μK2 and kinematic SZ power of DkSZ=1.75±0.86μK2" @NSF #southpole #Antarctica arxiv.org/abs/2601.20551

Picture of the @uw_icecube Upgrade team photo this season! Congrats to IceCube collaboration for a successful upgrade deployment this season! @NSF #southpole #Antarctica

What is the universe made of? Experts weigh in on the mysterious force that shapes our cosmic history As the Dark Energy Survey (DES) releases its final results, we caught up with two physicists who've been involved in the project from its early days. In this Q&A, Josh Frieman, DES co-founder and ...

Interesting history from Josh Frieman about
@theDESurvey: "In 2003, we started thinking about how to do (DES) .. a major motivation was a new cosmic microwave background telescope being built at the South Pole - the South Pole Telescope" phys.org/news/2026-01...

Spotting Astrophysical Discoveries at the Bottom of the World The South Pole Telescope has gathered new data on cosmic flares from white dwarf stars, demonstrating its unique capabilities.

Nice article by @doescience summarizing the recent SPT-3G result by Yujie Wan, which discovered two flaring objects near the #Galactic center! @NSF @NSF_NSB #southpole www.energy.gov/science/arti...

Exciting new result from SPT-3G by Yujie Wan from Illinois! Detection of transient white dwarves, near the Galactic center!
@NSF #Antarctica #southpole

www.ncsa.illinois.edu/2026/01/20/r...

The happy 13 participants in the South Pole marathon this weekend! Pic by Kurt Studt, taken right before the start. #Antarctica #southpole #marathon
@NSF

This past weekend was the annual #southpole marathon! Since 2011, the marathon has been run annually in January (yes, outside!), usually consisting of 6-8 loops around station. All-time record is 4hrs02min by Ricky Gates in 2011! Pic by Michel Adamic. #Antarctica @NSF

One of the big summer infrastructure projects is digging of a new intermediate sewer outfall tunnel. Here is a pic from Rich Overbeck earlier this summer early on in the project. #Antarctica #soutpole
@NSF

Yes, that would be fine!

On New Years Day at the #southpole, there is a ceremony to move the geographic South Pole (since the ice underneath the station moves about 10-meters per year) and a reveal of a new marker on top of the Pole. See some pics by Anjali from this years ceremony. #Antarctica @NSF

Happy Holidays! The #Christmas Day picture from the @NSF Amundsen-Scott South Pole station! Picture by Michael Rayne. #Antarctica #southpole

Pueo is launching! #Antarctica #southpole @NASA Watch live here: video.ibm.com/channel/nasa...

Three days after launch, the GAPS (dark matter) balloon is doing well. Waiting for PUEO to launch, the balloon facility webcam is still capturing interesting activity: a LC-130 on deck and an Emperor penguin in the foreground @NASA #Antarctica www.csbf.nasa.gov/antarctica/p...

Group photo of the SPT team at #southpole this season: Adam, Matt, Sasha, Michel, Anjali, and Nick! (Kyra not pictured!). We have a light season this year, doing some work on SPT-SLIM but otherwise observing all Austral summer!
@NSF
#Antarctica

It launched! 15-in in the air thus far. Ended up being the GAPS experiment, PUEO is up next! www.csbf.nasa.gov/antarctica/p...

Looking promising that someone might launch today from McMurdo balloon facility! Seems likely that it's Pueo. Follow at: www.csbf.nasa.gov/antarctica/p... #Antarctica #NASA #neutrinos

New results showing constraints on cosmic inflation using the latest CMB & BAO data sets, including SPT-3G temperature and polarization power spectra from this year! Also with public likelihood on Github! arxiv.org/abs/2512.10613 @NSF @doescience

Exciting times in McMurdo for the @NASA balloon payloads! This season, the GAPS and PUEO experiments are scheduled to launch, looks like GAPS is doing a "hang test", one of the last tests that is done before launch! Follow progress at: www.csbf.nasa.gov/antarctica/p...

The first South Pole Overland Traverse (SPOT) of the season arrived at the #southpole this week! There are three traverses that travel between McMurdo and Pole each season, which bring about 75% of the fuel in each season. Pic by Michael Rayne. #Antartica @NSF

New measurements from @NOAA measurements @NSF
South Pole Amundsen-Scott Station about the Ozone hole. Article includes an amazing picture from SPT winterover Sim Bash! #Antarctica #southpole t.co/NaWOSPanNa

Bad visibility at the #southpole this weekend, see side by side pic by IceCube Kurt that shows the walk to SPT and dark sector over the past few days! This only happens a couple days per year, but thats why they have the flag line along the path! @NSF #Antarctica #whiteout