Bruce Jakosky: MAVEN and the investigation of how Mars lost its atmosphere
To understand why Mars is cold and dry today, Bruce Jakosky and MAVEN look beyond the surface to the upper atmosphere and the processes that let gases escape to space.
PeriodUniversity of Colorado, MAVEN, Mars climate
RolePlanetary scientist and founding MAVEN principal investigator
Mars connectionUpper atmosphere, atmospheric escape, climate and habitability
Key pointUnderstand present Mars by measuring what the planet is still losing
Direct answer
Bruce Jakosky was the founding principal investigator of MAVEN, the NASA mission designed to study Mars’s upper atmosphere and determine how gases escape to space. His work directly connects evidence for a wetter ancient planet with the cold, thin-atmosphere Mars seen today.
MAVEN does not travel backward in time. It measures present processes — solar-wind interaction, radiation, ions and atmospheric escape — and combines them with other evidence to reconstruct climate history. The distinction between present measurement and historical extrapolation is essential to rigorous Mars science.
Essential timeline
Scientific careerLong-term research on Mars, climate and planetary evolution.
2008–2009MAVEN selected and developed under Jakosky’s scientific leadership.
November 2013MAVEN launches.
September 2014Mars orbit insertion and beginning of the science campaign.
2014–2021Jakosky leads the mission science through its first seven years of orbital operations.
2021Principal-investigator leadership transitions to Shannon Curry.
The climate question behind the red planet
Mars preserves valleys, minerals and sediments that point to ancient environments unlike the cold desert of today. A central problem is therefore how a planet that could sustain liquid water lost a large fraction of its atmosphere.
Jakosky approaches the problem through exchanges among atmosphere, Sun and space. The upper atmosphere is an active boundary where photons and particles transfer energy and can help atmospheric constituents escape.
MAVEN looks upward to understand the ground record
While rovers and orbiters map rocks, MAVEN measures composition, ions, fields and particles in the upper atmosphere. That perspective provides direct observations of escape mechanisms operating now.
The mission demonstrates the value of complementary scales: surface geology records cumulative outcomes, while present atmosphere measurements reveal mechanisms in action. No single source can reconstruct billions of years alone.
Solar wind, radiation and the absence of a global field
Mars lacks a present global magnetic field comparable with Earth’s, allowing more direct solar-wind interaction with the upper atmosphere, although the detailed physics also involves localized crustal fields and several escape processes.
MAVEN measures how solar activity changes atmospheric loss. That does not mean solar wind alone explains all climate evolution, but it supplies a measurable part of the budget.
What MAVEN changes in terraforming discussions
Any discussion of a thicker Martian atmosphere has to account for atmospheric evolution and the volatile inventories that actually exist. Escape mechanisms prevent the atmosphere from being treated as a quantity that can simply be added once and forgotten.
For settlement, the nearer-term conclusion is simpler: habitats will remain artificial pressurized environments for a very long time. MAVEN provides planetary context, not evidence for rapid transformation of Mars.
Leading and then handing over a long mission
In 2021 Jakosky transferred MAVEN science leadership to Shannon Curry after years of development and seven years of orbital operations. That transition is a form of institutional maturity.
Mars programs last decades. An organization that depends indefinitely on one founder becomes fragile. MAVEN shows that transfer of responsibility is part of scientific resilience, just as redundancy is part of technical resilience.
Verification rule: this biography prioritizes institutional, archival and primary sources. Statements about living people or active programs are dated and attributed; uncertain or disputed points must remain explicitly qualified.
