According to recent studies, winds moving around a planet outside of our
solar system are above 2 kilometers per second.
The University of Warwick's finding is the first direct measurement and
mapping of a weather system on a planet outside of our solar system.
The measured wind speed is 20 times faster than the fastest wind that has
ever been recorded on Earth, which would be seven times the speed of
sound.
Lead researcher Tom Louden of the Astrophysics department at the University
of Warwick commented on the discovery and said:
The first weather map ever from beyond the solar system is this one.
Although wind has been seen on exoplanets in the past, we have never been
able to directly quantify and map a weather system.
The Warwick researchers assessed the velocities on the two sides of the
exoplanet HD 189733b and found a strong wind flowing from its dayside to its
night side at a speed of around 5400mph. Mr. Louden clarifies:
Using high resolution spectroscopy of the sodium absorption present in its
atmosphere, HD 189733b's velocity was calculated. The Doppler effect alters
the wavelength of this characteristic when HD 189733b's atmosphere moves
toward or away from the Earth, allowing the velocity to be estimated.
Mr. Louden explains how this data was applied to determine velocity as
follows:
The proportional quantity of light blocked by various areas of the
atmosphere varies as the planet travels in front of the star because the
star's surface is brighter in the center than it is at the periphery. Our
velocity map results from the first time we utilized this data to measure
the velocities on different sides of the globe independently.
The methods employed, according to the experts, may aid in the study of
planets like Earth. Dr. Peter Wheatley, a co-researcher from the University
of Warwick's Astrophysics Group, says as follows:
We are overjoyed to have figured out how to map the weather systems of
other worlds. We will be able to examine wind flows in more detail and
create weather maps of smaller planets as we perfect the approach. We will
eventually be able to image the weather systems of Earth-like planets thanks
to this approach.
One of the "Hot Jupiters," a group of planets, HD 189733b, is one of the
most researched. HD 189733b is almost 10% the size of Jupiter and is 180x
closer to its star than Jupiter is, with a temperature of 1800°C.
Astronomers frequently target it due to its size and proximity to our solar
system. According to earlier studies, the planet's dayside would seem
brightly blue to the human eye because of clouds of silicate particles high
in its atmosphere.
The High Accuracy Radial Velocity Planet Searcher at La Silla, Chile, was
responsible for gathering the data.
