AAS Nova
Martian dust storm season
When Mars is closest to the Sun, the whole planet can disappear under dust for months.
Mars has a strongly elliptical orbit, and southern summer coincides with closest approach to the Sun. The extra heating lifts dust, the dust absorbs more sunlight, and the feedback occasionally goes global: in 2018 a storm covered the planet for months and ended Opportunity by starving its solar panels. Nuclear-powered rovers are unaffected, which is a large part of why Curiosity and Perseverance are built the way they are. Global storms are not annual — roughly one Mars year in three.
Where it has come up lately
Related terms
Gravity assist
Stealing a fraction of a planet's orbital momentum to go faster for free.
Regolith
The layer of broken rock and dust covering an airless world — and a serious engineering problem.
Sample return
Bringing a piece of somewhere else back to a laboratory on Earth.
Opposition and conjunction
The two alignments that decide when a planet is worth looking at and when it is unreachable.
Questions
What is Martian dust storm season?
When Mars is closest to the Sun, the whole planet can disappear under dust for months.
Why does it matter?
Nuclear-powered rovers are unaffected, which is a large part of why Curiosity and Perseverance are built the way they are. Global storms are not annual — roughly one Mars year in three.