A humanoid robot named Qestr lasted about 3 km in the Antarctic Ice Ultra before its battery ran out. The human runners kept going, and some of them covered 100 miles. The gap shows where humanoid robots still fall short: not on balance or terrain, but on power in deep cold.
What happened at the Antarctic Ice Ultra
The race took place on November 8, 2026, near Ultima camp in Queen Maud Land, East Antarctica. The official Antarctic Ice Ultra website places the camp at about 70 degrees south. US-based endurance company Runbuk organizes the event, which offers distances from 50 km to 100 miles.
The start was set for 1 a.m. Because of the polar day, the sun stayed up through the night. Temperatures on the course sat around -24 C (-11 F).
Qestr lined up wearing a custom thermal jacket meant to shield its internal parts. Reuters first reported the robot’s entry on November 9. Organizer Oliver Wang told Reuters that Qestr was the first humanoid robot to take part in the event. The race website also lists Qestr as the first humanoid robot racing with humans.
The robot started without obvious trouble. After roughly 3 km, its battery was depleted and it withdrew. No official time was recorded for it.
How many runners took part
Reports differ on the size of the field. Several outlets say Qestr ran with 25 human competitors. Pplware quotes a CBS News post that describes 24 human participants, which would make 25 entrants in total. The organizer has not published a full entry list for the robot’s race.
Why the battery, not the ice, ended the run
According to news.at, Qestr did not fail because of ice, wind or uneven ground. The problem was its energy supply. The outlet notes that lithium-ion batteries lose performance in strong cold. A walking humanoid also needs a lot of power just to keep its balance.
Put simply, a battery is a chemical system. Cold slows the chemical reactions inside it, so the pack delivers less usable energy. A jacket can slow heat loss, but it cannot add energy. On a course measured in tens of kilometers, a 3 km run shows how small the margin was.
How Qestr compares with other robot endurance tests
Qestr is not the first humanoid to run long distances or work in the cold. The table below uses only reported results.
| Event | Robot | Conditions | Result |
|---|---|---|---|
| Beijing E-Town half-marathon, April 2025 | Tiangong Ultra | 21 km road course | Won the robot category in 2 h 40 min, with three battery swaps |
| Altay region, Xinjiang, reported March 2026 | Unitree G1 | About -47 C, in an insulated coat | More than 130,000 steps in the cold |
| Beijing robot half-marathon, April 2026 | Honor robot “Lightning” | 21 km road course | Finished in 50 min 26 sec |
| Antarctic Ice Ultra, November 2026 | Qestr | About -24 C, thermal jacket, snow | Withdrew after about 3 km, no time recorded |
The 2025 result comes from Reuters coverage of the first Beijing robot half-marathon. There, the Tiangong Ultra team said the robot switched batteries three times. Qatar News Agency reported that the 2026 winner’s 50:26 beat the human half-marathon world record. news.at names that robot as Honor’s “Lightning.” SlashGear reported that the Unitree G1 used a quick-release battery with about two hours of life.
The pattern is clear. Robots have finished long courses when teams can swap batteries along the way. They have also walked in deeper cold than Antarctica offered on race day. Qestr faced both problems at once, with no reported battery swap on a remote snow course.
The human results on the same course
The human field had a record day. The race website lists several new marks from the 2026 edition:
- Yusheng Ni ran 100 miles in 17:02:24, a men’s record that beat his own mark by more than five hours.
- Stephanie Case set the women’s 100-mile record at 17:31:39.
- Maria Danila set the women’s 100 km record at 13:34:08.
- Xiaoyan Fan set the women’s 50-mile record at 12:39:02.
- Vivian Lee set the 24-hour record with 93 miles.
What remains unclear
Several basic details are still missing from public reports:
- Who built Qestr. None of the verified sources names the maker or the team behind it.
- What battery it used, and how much capacity it had at the start.
- Whether the team planned battery swaps or support, as robot teams did in Beijing.
- Which distance Qestr entered. Reports describe it as a marathon attempt, but the event’s shortest listed race is 50 km.
What to watch next is whether the team returns for the 2027 edition. The race website lists it for November 11 to 16, 2027. A second attempt with a cold-rated power system would show whether this was a hardware limit or a planning one.
