If you wanted to look at weather and climate patterns on the Earth, you would put a satellite in orbit and watch the planet for a long time, looking for changes in the cloud layers and measuring wind speeds, etc. It isn’t a stretch to think that we could do the same for another planet, especially since most of the planets in the solar system have atmospheres. Jupiter, being the largest and heaviest planet, also has immense wind speeds and beautiful vortex features, some of which are larger than the Earth. But in order to understand these features, we have see how they change over time, just like cloud patterns on the earth. The good news is, NASA has been using the Hubble Space Telescope to do just that.
A program called the Outer Planet Atmospheres Legacy Program (OPAL), is using the Hubble Telescope to look at the atmospheres of the four gas giants of our Solar System on an annual basis to look for short and long term changes.
“Every time we look at Jupiter, we get tantalizing hints that something really exciting is going on. This time is no exception,” said Dr Amy Simon of NASA’s Goddard Space Flight Center.
One of the things the map has confirmed is that in recent years, the great red spot of Jupiter has been shrinking, and is continuing to shrink. Currently the spot is 240 Km smaller than it was in 2014, though this is a slow decline as the spot is over 16,000 Km across. It was once large enough to fit three Earth’s within it, but with the decline it can be covered with a single Earth.
The legacy images from OPAL will allow astronomers and climatologists to study how the winds and features change over the years, giving us a record of their state for future study.