Scrub through Mars's 687-day year to watch its dust-storm season come and go - then, once the slider sits inside that stretch of the orbit, trigger the real global dust storm that ended NASA's Opportunity rover mission in 2018.
Drag to orbit and scroll or pinch to zoom on the scene above. Press Play year to watch a full Mars year pass, or use Jump to dust season to land inside the tan-highlighted stretch before trying the storm button.
Mars Dust Storm Seasons 3D Explorer
This browser explorer shows why Mars has a dust-storm season at all: its orbit is noticeably egg-shaped (eccentricity 0.0935, about 5.6 times more eccentric than Earth's), so the extra sunlight Mars receives near perihelion and the southern-hemisphere summer solstice drives the strongest atmospheric circulation of the Martian year - and, roughly every three Mars years, a regional dust storm inside that window grows into a storm big enough to wrap the whole planet.
Scrub the day slider and Mars moves along a heliocentric orbit ellipse drawn to its real eccentricity; the tan-highlighted arc marks the recognized dust-storm season (areocentric solar longitude, or Ls, 180 to 340 degrees), with an orange dot at perihelion (Ls 251), a yellow dot at the southern summer solstice (Ls 270), and a blue dot at aphelion. Inside the tan arc, small illustrative dust patches appear on Mars and the facts panel reports an atmospheric-opacity (tau) reading in the range NASA's Curiosity rover has actually measured during dust season. Once the slider sits inside that window, the "Trigger a global dust storm" button raises the scene to the real tau of about 10.8 that NASA/JPL recorded near Opportunity during the 2018 storm, thickens the dust shroud around the whole planet, and drops the illustrative solar-panel-power bar to the low level that left Opportunity unable to recharge - the storm that ended its 15-year mission in February 2019.
- Day slider (0 to 687, one full Mars year) moves Mars along its real-eccentricity orbit ellipse and updates the areocentric solar longitude (Ls) readout live
- Play year auto-scrubs through a full Mars year; Jump to dust season lands inside the tan-highlighted Ls 180-340 window
- Trigger a global dust storm raises the scene to the real 2018 tau of about 10.8 - only enabled while the slider sits inside the dust-storm season, since global storms have never been observed outside it
- Facts panel states the current Ls, day of year, distance from the Sun, whether the slider is inside the dust-storm season, the atmospheric-opacity (tau) reading, and an illustrative solar-panel-power bar
- Perihelion, southern-summer-solstice, and aphelion markers sit fixed on the orbit ellipse so you can see how close the dust season sits to Mars's closest approach to the Sun
- Drag to orbit, scroll or pinch to zoom
- Runs fully in the browser with the vendored three.js engine - no account, no upload
| Figure | Value | Source |
|---|---|---|
| Mars orbital period | 686.98 Earth days | NASA NSSDCA Mars fact sheet |
| Orbital eccentricity | 0.0935 | NASA NSSDCA Mars fact sheet |
| Perihelion / Aphelion | about 206.62M km / 249.23M km | NASA NSSDCA Mars fact sheet |
| Dust-storm season | Ls about 180 to 340 degrees | Published planetary-science convention |
| Perihelion / Southern summer solstice | Ls 251 deg / Ls 270 deg | Published planetary-science convention |
| Global-storm recurrence | about every 3 Mars years (~5.5 Earth years) | NASA/JPL |
| 2018 storm tau near Opportunity | about 10.8 | NASA/JPL, 2018 mission updates |
| 2007 storm tau (Opportunity survived) | about 5.5 | NASA/JPL |
| Curiosity's typical seasonal tau (Gale Crater) | about 1.0 to 2.0 | NASA/JPL, 2018 mission updates |
Students studying planetary science, and anyone curious why a single dust storm could end a working Mars rover, can use the day slider to connect the orbit shape to the season and the season to the real 2018 event without reading a research paper first. For the mechanism behind why Mars's atmosphere is thin in the first place, rather than its year-to-year weather, see the Atmosphere Escape: Mars 3D Explorer. For Mars's real surface relief instead of its weather, see the Mars Terrain 3D Explorer. For the very different, axial-tilt-driven mechanism behind Earth's seasons, see the Seasons Explorer, and for Earth's own, much rounder orbit ellipse (eccentricity 0.0167), see the Earth Perihelion and Aphelion 3D Explorer.
Everything renders on your device with WebGL. The 3D engine loads once (about 0.7 MB) and is cached; no scene data is sent to a server.
This is an educational approximation, not a climate simulation. Mars's position on the orbit ellipse is a smooth Keplerian model using the real eccentricity and perihelion/aphelion distances, not a day-by-day ephemeris; the in-season tau curve is shaped to land within Curiosity's documented range rather than a measured day-by-day record, and the solar-panel-power bar is an illustrative decreasing function of tau rather than NASA's measured power curve for Opportunity's specific solar array. Only the 2018 and 2007 storm tau values, Curiosity's documented seasonal range, and the Ls 180-340 season window are direct published figures.
Frequently Asked Questions
Why does Mars have a dust-storm season at all?
Mars's orbit is noticeably eccentric (0.0935, about 5.6 times more eccentric than Earth's). Near perihelion and the southern-hemisphere summer solstice, Mars gets extra sunlight, which drives the strongest atmospheric circulation of the year - the conditions regional dust storms need to sometimes grow into a global storm.
When is Mars's dust-storm season?
Roughly Ls 180 to 340 degrees (areocentric solar longitude) - a stretch that brackets perihelion (Ls 251) and the southern-hemisphere summer solstice (Ls 270). Global, planet-encircling dust storms have not been observed outside this window.
How often does a global Mars dust storm happen?
Roughly every 3 Mars years, or about 5.5 Earth years, on average - NASA has not identified exactly why the interval is roughly that length.
What ended NASA's Opportunity rover?
The 2018 global dust storm. Local atmospheric opacity (tau) near the rover reached about 10.8, blocking enough sunlight that Opportunity's solar panels could not recharge its batteries. NASA declared the 15-year mission over in February 2019.
Did Mars survive a dust storm before 2018?
Yes - a 2007 global dust storm reached a milder tau of about 5.5 near Opportunity, and the rover survived that event on reduced power.
Why didn't the 2018 storm affect Curiosity the same way?
Curiosity is powered by a radioisotope generator rather than solar panels, so it kept operating through the storm. Its instruments recorded a typical seasonal dust opacity of about 1.0 to 2.0 in Gale Crater - the range this scene's dust-season tau curve is shaped to land within.
What is "tau" in this scene's facts panel?
Atmospheric opacity - a measure of how much dust is blocking sunlight. Higher tau means less light reaches the surface. NASA/JPL measured tau near 10.8 during the 2018 storm and near 5.5 during the milder 2007 storm.
Is the solar-panel-power bar a real NASA measurement?
No - it is an illustrative decreasing function of tau, shaped so it drops low during the triggered storm, not NASA's measured power curve for Opportunity's specific solar array.