How NASA's Artemis Astronauts Will Decide Where to Go and What to Do on the Lunar Surface
Imagine stepping onto the surface of the Moon. The Earth hangs, a beautiful blue marble, in the black velvet sky. You are one of the first astronauts to return to the lunar surface in over 50 years. But you don't have time to just stare. Your oxygen is limited, your rover has a finite charge, and you have a mission to accomplish. Every single step you take has been meticulously planned by a team of scientists and engineers on Earth. This is the science of the "traverse"—the carefully choreographed journey of exploration across an alien world.
A single moonwalk may last only 6-8 hours, constrained by life support systems and rover battery life.
Temperatures swing from scorching heat to freezing cold, with hazardous craters and slopes.
Every minute and every kilogram of weight is precious, requiring maximum scientific return.
The goal of traverse planning is to create an efficient "field trip" that collects the most valuable data and samples to answer fundamental questions about the history of the Moon, the Solar System, and our own planet.
Let's dive into a fictional but realistic future mission. The setting is the Schrödinger Basin, a giant impact crater near the Moon's south pole. This location is a scientific treasure trove: it contains peaks exposed to near-constant sunlight for power, permanently shadowed craters that may harbor water ice, and "peak rings" that expose deep layers of the lunar crust.
This crucial EVA is designed to test a central hypothesis: "That the impact which formed Schrödinger Basin excavated material from the lunar mantle, and that subsequent volcanic activity deposited volatile compounds (like water ice) in the adjacent shadowed regions."
The astronauts' second EVA is a complex, 7-hour traverse. Here's how it unfolds:
The crew departs the habitat in their pressurized rover. They are driven to the first "waypoint" on the plan.
Activity: Geological reconnaissance and sample collection.
Procedure: The astronauts use a geological hammer and chisel to collect rocks from the crater's rim. They take detailed photographs of the rock layers (strata) and use a handheld X-ray spectrometer to determine the elemental composition on the spot.
Activity: Volatile prospecting and core sampling.
Procedure: The rover parks at the very edge of a permanently shadowed crater. One astronaut uses a 1-meter drill corer to extract a vertical sample of the soil (regolith). This core is sealed in a special container to prevent contamination and sublimation. Meanwhile, the second astronaut deploys a Neutron Spectrometer probe into the shadowed area to measure the hydrogen signature, a proxy for water ice.
Activity: Searching for volcanic glass beads.
Procedure: At a small, suspected volcanic vent, the crew uses a rake and sieve to carefully separate fine-grained material. They are looking for tiny, colored glass beads formed in ancient volcanic fire fountains—a potential source of lunar water.
The crew carefully stows all samples, powers down external instruments, and returns to the habitat, completing the EVA.
Back in the habitat, preliminary data is already telling a story. The real deep analysis happens later on Earth, but the initial findings are thrilling:
The X-ray spectrometer at Waypoint 1 detected unusual concentrations of magnesium and iron, consistent with mantle rocks, supporting the idea that the impact excavated deep material .
The neutron spectrometer at Waypoint 2 showed a strong hydrogen signal, strongly suggesting the presence of water ice just below the surface .
The sieve samples from Waypoint 3 contained abundant orange glass beads, confirming past volcanic activity .
The scientific importance is profound. By connecting the mantle rock, the water ice, and the volcanic glass, we can build a timeline of the Moon's geological history. Did the water come from the volcanic eruptions? Or was it delivered later by comets and trapped in the cold shadows? The samples from this single, well-planned traverse will help us find the answer.
| EVA Elapsed Time | Waypoint | Primary Activity | Key Objective |
|---|---|---|---|
| 0:00 - 0:30 | -- | Transit | Drive from habitat to Waypoint 1 |
| 0:30 - 2:00 | 1 | Geology Station | Sample crater rim material for deep crust/mantle analysis |
| 2:00 - 2:30 | -- | Transit | Drive to edge of permanently shadowed crater (PSC) |
| 2:30 - 4:00 | 2 | Volatiles Station | Drill core sample & measure subsurface hydrogen |
| 4:00 - 4:15 | -- | Transit | Drive to volcanic vent feature |
| 4:15 - 5:45 | 3 | Volcanics Station | Sample regolith for volcanic glass and minerals |
| 5:45 - 6:15 | -- | Transit | Return to habitat |
| 6:15 - 7:00 | -- | Post-EVA | Sample stowage and equipment cleanup |
| Sample ID | Waypoint | Description | Mass (g) | Special Handling |
|---|---|---|---|---|
| ART7-E2-W1-01 | 1 | Breccia (impact rock) | 450 | Standard Container |
| ART7-E2-W1-02 | 1 | Anorthosite (crustal rock) | 380 | Standard Container |
| ART7-E2-W2-01 | 2 | 80cm Regolith Core | -- | Sealed, Cold Storage |
| ART7-E2-W2-02 | 2 | Surface Scoop from PSC edge | 120 | Sealed, Cold Storage |
| ART7-E2-W3-01 | 3 | Sieved Volcanic Beads | 95 | Standard Container |
A "tricorder" for elements. It bombards rocks with X-rays to instantly reveal their chemical composition, allowing astronauts to identify scientifically valuable samples on the spot .
The mobile base and lifeboat. It provides a shirt-sleeve environment for long drives, allowing the crew to travel further without the fatigue and time of suiting up .
A subsurface time machine. This drill extracts long, vertical tubes of soil, preserving the layers. This allows scientists to study the history of impacts and deposition over millions of years .
A water divining rod. It measures neutrons bouncing back from the soil. A decrease in neutron flux indicates the presence of hydrogen, which is most likely bound in water molecules (H₂O) .
The intricate dance of a lunar traverse—from the initial orbital surveys to the final sample stowage—showcases the incredible synergy between human intuition and robotic precision. It's a discipline born from the Apollo missions and refined with modern technology.
As we prepare for the Artemis generation to leave their footprints in the lunar dust, it is this meticulous science of the traverse that will ensure those footprints lead us to profound new discoveries. The path they walk is a map not just of the Moon, but of our own expanding presence in the cosmos.