Did Mexican World Cup fans' celebrations shake the earth?
Mexican football fans could hardly contain their joy when Hirving Lozano scored a goal against Germany in Mexico's opening game of the World Cup.
But did their jubilant stomping really cause an earthquake as some media have reported?
A tweet from Mexico's Institute of Geological and Atmospheric Investigations would suggest so.
The tweet by the institute, which monitors seismic activity, reads: "Artificial quake in Mexico City due to celebration of goal by the Mexican team in the game against Germany during the 2018 World Cup in Russia."
The image highlights the moment of the goal with a red rectangle on the seismogram. This shows localised shaking near the seismometer.
The tweet then points readers to a more detailed blog post (in Spanish).
What really happened?
The institute confirms that two of its seismometers local to celebrating fans picked up ground movement immediately after the winning goal against the defending champions.
"During the game, the Mexican team managed to score 35 minutes and seven seconds in, at this moment our monitoring systems detected a seismic movement with an acceleration of 37m/s2 picked up by at least two sensors inside Mexico City. These were very probably produced by the massive celebrations," the blog reads.
The Institute of Geological and Atmospheric Investigations then goes on to clarify that "such events are not at all big".
It points out that only very sensitive equipment located near celebrating crowds would pick up such activity.
One of the main sites where fans gathered, Mexico City's Angel of Independence statue, is not far from one of the seismometers which registered the movement.
Was it a quake or not?
On its blog, the Institute of Geological and Atmospheric Investigations makes it clear that such events cannot be felt by the general population.
"These [events] can't be measured in magnitudes, which is why they are not called quakes, or if they are, they have to be accompanied by the word 'artificial' to show clearly that it is not a geological event," the blog explains.
How wild were the celebrations?
Judge for yourself:
Has something like this happened before?
Yes, a 1988 college American football game between Louisiana State University and Auburn was dubbed "Earthquake Game" after an LSU touchdown in the last minutes of the game caused fans in Tiger Stadium to erupt in such celebrations that it was picked up by a seismometer in the university's geosciences complex.
A blip coinciding with the winning touchdown could be seen on the seismograph.
More recently, Leicester City fans caused a tremor when they celebrated a last-minute goal against Norwich in 2016.
As in Mexico City and at Louisiana State University, it was picked up by a seismometer installed near celebrating fans.