Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Mach disk during champagne cork popping at 20°C.

Champagne stored at 20 °C releases a blueish plume when the cork is popped. Credit: Equipe Effervescence/CNRS/Univ. Reims

Physics

An uncorked champagne bottle imitates a fighter jet

On opening, a bottle of bubbly releases a carbon dioxide plume that travels faster than the speed of sound.

The ‘pop’ of a champagne cork unleashes a supersonic jet of freezing gas.

As the pressurized carbon dioxide in the neck of the bottle is released, the gas cools and condenses, forming a cloudy jet. To investigate this phenomenon in detail, Gérard Liger-Belair at the University of Reims Champagne–Ardenne in France and his colleagues used a camera that records 12,000 frames per second to film corks bursting from the necks of champagne bottles.

The footage revealed that characteristic shock waves called Mach disks form in the CO2 jet — indicating that the gas is travelling faster than the speed of sound. Mach disks are also seen in the exhaust trails of fighter jets.

The team found that changing the champagne’s temperature altered the CO2 jet’s appearance. The jet from a champagne bottle stored at 30 ºC formed large CO2 ice crystals that scattered light in a manner similar to clouds, and appeared white or grey. But ice crystals in the jet from a bottle cooled to 20 ºC were finer and preferentially scattered blue light, resulting in an evanescent blue plume.

More Research Highlights...

Light micrograph of a human egg cell during fertilisation

As a human egg cell is fertilized, two chromosome-containing cellular structures (dotted circles, centre) merge into one — a process that often goes wrong. Credit: Pascal Goetgheluck/Science Photo Library

Developmental biology

The error-prone step at the heart of making an embryo

High-resolution imaging shows why the union between two sets of chromosomes goes awry as least as often as not.
Satellite image of broken iceberg B-44.

Dark water borders chunks of iceberg broken off a West Antarctica glacier. The melting of the region’s ice sheet could allow the bedrock to rise, sloughing water into the ocean. Credit: NASA

Climate change

Antarctic rocks on the rebound could raise sea level much more than expected

When the ice covering the west of the continent disappears, the bedrock could rise up and shove extra water into the ocean.
Monteverde Cloud Forest Preserve, Costa Rica

Mist wafts through the trees at the Monteverde Cloud Forest Biological Preserve in Costa Rica. Cloud forests around the world are threatened by development, wood collection and climate change. Credit: Stefano Paterna/Alamy

Conservation biology

Forests that float in the clouds are drifting away

Tropical cloud forests are safe havens for a vast range of creatures and plants, but they are under siege around the globe.
Illustration of a brown dwarf

A rapidly spinning brown dwarf (pictured, artist’s impression) tends to have narrow atmospheric bands; the faster the spin, the thinner the bands. Credit: NASA/JPL-Caltech

Astronomy and astrophysics

Dim stars that have failed at fusion are masters of spin

Three brown dwarfs whirl on their axes at a dizzying rate that might be close to the celestial speed limit for these bodies.
Aerial photograph of beef cattle standing at the Texana Feeders feedlot in Floresville, Texas

Large-scale facilities such as this feedlot in Floresville, Texas, help to meet the global appetite for beef and other red meat, which remains strong despite the growing consumption of chicken and fish. Credit: Daniel Acker/Bloomberg/Getty

Agriculture

Meat lovers worldwide pay climate little heed

People are eating more poultry and fish — but they’re not giving up their hamburgers.
Midshipmen at dining table eat in formation, CIRCA 1900

Midshipmen in the United States in around 1900. A study found that body-mass index, a gauge of obesity, has increased with the generations during the twentieth century. Credit: Buyenlarge/Getty

Metabolism

A century of US data documents obesity’s racially skewed rise

An analysis also finds that obesity is common at a much younger age among people born in the early 1980s than those born in the late 1950s.
Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing

Search

Quick links