Shooting stars are one of the most awe-inspiring astronomical events we can witness regularly. Meteor showers recur every year and they are named after the constellation they seem to originate from. However, according to a new study, they are actually coming from a different direction every night.
The NASA-backed CAMS (Cameras for Allsky Meteor Surveillance) project has been tracking more than 300 meteor showers over the past seven years. In doing so, it has discovered that the showers' point of origin moves over the time the Earth passes through the dust clouds and cometary fragments that make up the meteors.
The team filmed over 300,000 meteoroid trajectories using 60 low-light video cameras over the San Francisco Bay Area. They then selected 45 showers with an extreme range of motion to be visualized in an incredible animation.
"I was most surprised by some showers that were initially seen close to the plane of the planets, but then moved up towards the pole over the course of weeks," CAMS project leader Dr Peter Jenniskens, from the SETI Institute and NASA Ames Research Center, said in a statement.
For many of these meteor showers, the Earth’s gravity is enough to move the orbit of the streams. A good example is the Perseids that peak around August 10. They appear to radiate from the constellation of Perseus, but CAMS first detected the Perseids on July 1 from Cassiopeia and the last, on September 3, from the constellation of the Giraffe (Camelopardalis).
“The small daily drift of the Perseids is mostly due to Earth's motion around the Sun," added Jenniskens. "But after taking that into account, 18 short-period and 27 long-period showers are still seen to wander from night to night."
The researchers suspect that a larger and more influential planet is behind the changes. Jupiter is the likely culprit as some of these showers extend all the way to its orbit.
"Jupiter's gravity is likely responsible for warping these meteoroid streams by causing both the orientation of the orbital plane and the distance of closest approach to the Sun to change," Jenniskens stated. "The combination of the two creates conditions suitable for hitting Earth over weeks or months."
The research has been accepted for publication in the journal Planetary Space Science and can be read here.
