30 by 30 protected-area gap
Estimate the additional land and ocean area that must come under formal protection to reach the global 30 by 30 biodiversity target.
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63 of 63 challenges shown. News snapshots begin July 6, 2026.
Villa de Leyva helicopter water drops
Estimate the lift energy and realistic helicopter fuel scale behind 240,000 liters of wildfire water drops.
Europe jet-fuel deficit flights
Estimate how many commercial flights per day could be fueled by Europe's projected 510,000-barrel-per-day jet-fuel deficit.
Meta Alberta data center natural gas
Estimate the natural gas burned and CO2 emitted each day to supply a 250-MW AI data center with gas-fired electricity.
East-West pipeline pumping power
Estimate the mechanical power needed to move millions of barrels of crude oil per day through a 1,200-km pipeline.
Ice sheet loss and sea-level rise
Estimate how much global average sea level rises when 12.5 trillion U.S. tons of land ice enters the oceans.
Iran war cost in service-member years
Estimate how many active-duty service-member support-years are equivalent to $38 billion in combat-operation costs.
Atlantic no-hurricane probability
Estimate how unusual it is for an Atlantic hurricane season to reach September 15 without producing a hurricane.
Medicaid healthcare volume
Estimate the annual doctor visits, emergency-room visits, and clinician-hours associated with a 7-million-person Medicaid population.
Teen reading screen-time tradeoff
Estimate how many books U.S. 15-year-olds could read if each replaced 30 minutes of daily recreational screen time with reading.
$5,000 adult payment federal cost
Estimate the total cost of a $5,000 payment to every adult U.S. citizen and how many days of federal revenue it would equal.
Duane Arnold nuclear restart electricity
Estimate how much electricity a restarted 615 MW nuclear plant could generate and how many years of gross power value would equal a $1.9 billion loan.
Canada tariff-affected truckloads
Estimate how many daily truckloads are represented by about US$20 billion in U.S. goods affected by Canada's new counter-tariffs.
Polysilicon solar panel cost
Estimate how much a fourfold polysilicon price premium adds to one solar panel and to a 1 GW solar project.
Federal debt interest cost
Estimate the annual interest cost of $40 trillion in U.S. federal debt, then convert it into a per-household burden.
Google AdX auctions per second
Estimate how many ad auctions Google might run every second, then compare the flow with daily and annual ad-market dollars.
Indonesia wildfire carbon vs cars
Estimate how many average U.S. gasoline cars driven for a year would match one week of reported Indonesian wildfire carbon emissions.
Hurricane Karina kinetic energy
Estimate the kinetic energy stored in the hurricane-force wind field of a Category 4 Pacific storm, then compare it with household electricity use.
Nepal glacier-collapse warning time
Estimate how much usable warning time communities 20 km downstream had before a glacier-triggered debris flow and flood arrived.
DXB passenger traffic drop
Estimate how many aircraft movements disappeared when Dubai International Airport lost 14.5 million passenger journeys in the first half of 2026.
Visa revocation administrative workload
Estimate the staff-hours and worker-years involved in processing up to 200,000 visa revocations.
Tiangong robot sprint energy
Estimate the battery energy and peak power behind a humanoid robot running 100 meters in less than 9 seconds.
Mediterranean upper-ocean heat
Estimate how much thermal energy is stored when the Mediterranean's upper ocean is warmed by about 2 degrees C.
Satellite streak probability
Estimate when satellite constellations make long-exposure astronomical images likely to contain at least one bright streak.
Zhuque-3 booster reuse hardware
Estimate how much first-stage rocket hardware is saved when one recovered booster replaces fresh boosters across 20 launches.
Ulchi Freedom Shield logistics
Estimate food, water, fuel, and truckload logistics for an 18,000-troop exercise shortened from 11 days to five.
Microdrama human attention
Estimate annual U.S. microdrama viewer-hours, episode-views, revenue per viewer-hour, and revenue per episode viewed.
MMR split healthcare workload
Estimate the extra clinic staff time, parent time, supplies, and appointment slots created if the combined MMR vaccine were split into separate visits.
Hydromax 406 mph power
Estimate the mechanical power and hydrogen use required for a hydrogen-burning streamliner to run a flying mile at 406 mph.
Oman oil slick thickness
Estimate how thin 800,000 barrels of crude would be if spread over 2,000 km2, then work backward from realistic slick thickness.
Wolf-Rayet supernova kinetic energy
Estimate the kinetic energy carried by supernova ejecta moving near 0.1c, then compare it with earthquakes, human energy use, and solar output.
CATL lithium mine EV batteries
Estimate how many EV battery packs one year of Jianxiawo lithium output could support, then compare that with China-scale EV production.
El Nino food aid logistics
Estimate the staple food, shiploads, truckloads, and global grain-production share needed if El Nino pushes 49 million more people into acute food insecurity.
Congo Ebola contact tracing force
Estimate active contacts, daily monitoring interactions, and full-time tracers or mobile teams required during a fast-moving Ebola outbreak.
Rare rogue AI behavior testing
Estimate how many tasks, parallel agents, and human reviewers are needed to catch a one-in-100,000 dangerous action within 30 days.
Australia EVs and gasoline imports
Estimate whether additional Chinese EV imports can explain a substantial share of Australia's reported 15% gasoline-import decline.
Spider-Man theater capacity
Estimate ticket sales, screenings, audience-hours, and the screen capacity used by a record $360 million opening weekend.
Spokane wildfire evacuation traffic
Estimate vehicles, lane-hours, traffic length, and outbound-lane needs for a 60,000-person wildfire evacuation.
Amazon AI capex power demand
Estimate how much continuous electrical load Amazon's $220 billion AI and data-center spending plan could eventually add.
Japan quake production backlog
Estimate delayed auto and semiconductor output after the Kumamoto earthquake, then calculate how spare capacity controls catch-up time.
Iran strike wave logistics
Estimate strike sorties, aircraft-hours, jet fuel, tanker loads, and the hidden support package behind a two-hour strike wave.
Southwestern Japan earthquake energy
Estimate the energy released by a magnitude 7.1 earthquake, compare it with gasoline, household electricity, and Starlink reentry energy, then check the 6.8 sensitivity case.
Betelgeuse companion orbit
Estimate the orbital period, orbital speed, and century-scale observing context for Betelgeuse's newly imaged companion.
A350-1000ULR nonstop fuel efficiency
Estimate total jet fuel, fuel per passenger, and liters per passenger per 100 km for a 24-hour nonstop test flight.
Facial recognition at a mass protest
Estimate face detections, watchlist comparisons, false alerts, video storage, and human-review load during one protest day.
Energy from 20 reentering Starlinks
Estimate the combined kinetic energy of 20 Starlink V3 test satellites reentering after Starship Flight 13.
Distributing 500 million sterile flies
Estimate the mass, packed volume, and weekly aircraft release flights needed to distribute sterile screwworm flies at suppression scale.
Lake Powell boat-ramp extension
Estimate the ramp length, concrete volume, mass, truckloads, and cost needed if Lake Powell drops another 33 vertical feet.
AI-chip fabs as city-scale infrastructure
Estimate the power and water demand of four advanced semiconductor fabs, then compare the hub with city and metro-scale utility loads.
Wildfire smoke exposure dose
Estimate the total extra PM2.5 mass inhaled across an affected region during one smoky wildfire day.
Texas flood runoff rate
Estimate the flood-wave flow produced when 10 to 20 inches of rain falls over a steep Texas Hill Country watershed.
Import prices and household budgets
Estimate what a 7.1% rise in import prices might cost the average household after import exposure and pass-through are included.
Offshore wind radar horizon
Estimate whether large offshore wind turbines 20 to 60 km from shore are geometrically visible to coastal radar before Earth curvature hides them.
Immigration arrest throughput
Estimate officer-days per arrest during a large enforcement surge, then compare full-network and field-team staffing assumptions.
World Cup hydration heat balance
Estimate how much heat a soccer player produces in one half, then convert that heat load into liters of sweat evaporation.
Mayon ashfall distance
Estimate how far volcanic ash can drift downwind before settling, using plume height, wind speed, and ash settling speed.
Bangkok pub fire egress rate
Estimate how many usable doorway-equivalents a crowded pub would need to evacuate several hundred people before smoke conditions become life-threatening.
Heat dome AC demand in power plants
Estimate extra peak electrical demand from air conditioning during a large U.S. heat dome, then compare it with 1-GW power plants.
Strait of Hormuz oil in car fill-ups
Estimate how many average U.S. car fill-ups are equivalent to one day of oil normally passing through the Strait of Hormuz.
America's daily coffee habit
An April 2026 survey reported that 66% of American adults drank coffee during the previous day. Estimate how many gallons that represents.
U.S. electricity-demand growth in household terms
Estimate how many average households could be powered for a year by the projected increase in total U.S. electricity use from 2025 to 2027.
World Cup fan time vs. worker-years
Estimate total human time spent inside stadiums by 2026 FIFA World Cup fans, then convert that collective attention into full-time work years.
Lincoln Memorial Reflecting Pool vs. backyard pools
Estimate annual U.S. residential pool maintenance spending, then compare it with the reported $16 million-plus Reflecting Pool project.