Mars Explorer Curiosity Discovers Vibrant 'Dusk Clouds' in Unanticipated Hue
In an unexpected twist, NASA's Curiosity rover caught a spectacle back in January 2023, depicting a feather-like cloud illuminating in the Martian sky shortly after sundown. This striking sight was recently highlighted by NASA, showcasing Curiosity's investigation of the Red Planet's skies conducted last month.
The 16-minute image series, captured on January 17 or Sol 4426 on Mars, revealed reddish-green hues against the Martian twilight. The celestial phenomenon, known as noctilucent clouds, is a result of the Sun's light scattering in the dusty Martian atmosphere.
According to NASA, Mars' clouds are either water ice or carbon dioxide ice. The former clouds form at lower altitudes and temperatures, while the latter, found at higher altitudes, are responsible for the night-shining effect observed. Noctilucent clouds in Mars' atmosphere occupy an altitude range between 37 to 50 miles (60 to 80 kilometers) above the Martian surface, evaporating below approximately 31 miles (50 kilometers) due to rising temperatures.
Remarkably, Earth's illuminated clouds share similarities with Martian noctilucent clouds. Caused by rocket launches, these Earthly clouds reveal the planet's hidden beauty in the post-sunset or pre-sunrise skies.
Mars' clouds carry distinctive shapes and sizes. In 2022, ESA scientists spotted cloud formations similar to those on Earth within the Red Planet's skies. In 2023, Perseverance rover greeted heavy cloud cover, foreshadowing the overcast days ahead. The recently imaged iridescent clouds are not a new discovery but remain an intriguing sight to behold.
The first reported observation of twilight clouds on Mars can be traced back to NASA's Pathfinder mission in 1997. Curiosity repeated the observation in 2017, and this latest sighting marks the fourth Mars year the rover has spotted the enchanting clouds.
Late last year, NASA researchers published a study in the Geophysical Research Letters revealing how the iridescent effect underscores how ice forms and grows in Mars' atmosphere. With consistent Mars observations, scientists can unravel mysteries about the Red Planet's climate and weather patterns. As Mark Lemmon, the study's lead author, noted, the predictable appearance of the clouds boosts our confidence in understanding the Red Planet's atmospheric dynamics.
The discovery of noctilucent clouds on Mars is a testament to the ongoing exploration of science and technology in space. This future of Mars investigation highlights the potential of discovering more earthly analogues, such as these clouds, on other planets. The recent image series captured by Curiosity on January 17, 2023, showcased the beautiful spectacle of these clouds, with dates like January 17 becoming significant milestones in Mars' atmospheric research. Additionally, the study published by NASA researchers in 2022 underscores the importance of high-resolution shots and consistent observations in understanding the Red Planet's climate and weather patterns.
