NASA said Orion’s Artemis II heat shield performed in line with engineering predictions and ground-test results. In its post-flight assessment, published October 15, 2026, NASA counted nine varying-size spots of char loss on Artemis II’s shield, compared with 103 on Artemis I. NASA’s assessment described a tenfold reduction in cracking and char loss, which it attributed to Artemis II’s changed entry profile.
Artemis II returned four astronauts to Earth on April 10, 2026. For a separate look at the flight’s lunar-science data, NeoTeo covered NASA’s first public Artemis II science-data release.
What NASA found on the heat shield
The nine and 103 figures count spots of varying sizes on the heat-shield dish. NASA separately compared pre- and post-flight laser scans to measure material recession. Orion’s shield contained 186 blocks of Avcoat, an ablative material that changes as it heats; NASA also reported that the spacecraft’s 1,300 ceramic backshell tiles performed as expected. NASA’s assessment says the capsule reached 39 times the speed of sound, with peak external temperatures above 4,000°F while the cabin remained in the mid-70s°F.
| Mission | Char-loss spots counted by NASA | Entry profile |
| Artemis I | 103 | Skip entry |
| Artemis II | 9, varying sizes | Modified entry without skip; shorter allowable downrange distance |
Why Artemis I lost char, and what changed for Artemis II
NASA’s investigation linked Artemis I’s char loss to gas pressure building inside low-permeability Avcoat during skip entry. Ground tests reproduced the anomaly, according to NASA’s technical abstract.
Artemis II flew without skip entry. NASA also shortened the maximum downrange distance between atmospheric entry and splashdown, reducing time in the temperature range associated with the Artemis I phenomenon. NASA attributed the tenfold reduction in cracking and char loss to this trajectory change; the change describes the entry profile, not a new heat-shield material.
NASA’s Orion entry paper explains that guided-entry banking regulates lift to control the capsule’s downrange and crossrange distance. It also describes continuous spinning as a contingency mode for ballistic entry. The NASA paper distinguishes those flight modes.
What NASA was still analyzing
In its October 15 assessment, NASA said it was comparing post-flight laser scans with pre-flight measurements to determine material recession. Sample extraction and further material and thermal analyses were also underway. The assessment therefore reported the spot count and engineering comparison while NASA’s recession measurements continued.
For Artemis III, NASA says the heat-shield design incorporates upgrades intended to improve Avcoat block uniformity and consistent permeability. NASA’s assessment describes those design changes.
