Landsat 9 will carry the same, and improved, instruments that were onboard Landsat 8 — the Operational Land Imager-2 (OLI-2) for reflective band data, and the Thermal Infrared Sensor-2 (TIRS-2) for the thermal infrared bands. OLI-2 will have a slightly improved signal to noise ratio over Landsat 8's OLI. TIRS-2 is a Class-B instrument with a 5-year design life, whereas Landsat 8's TIRS is a Class-C instrument with a 3-year design life. Additionally, TIRS-2 will incorporate a key improvement of stray light correction, an issue that was discovered on Landsat 8 TIRS post launch.
As with Landsat 8, Landsat 9 will have higher imaging capacity than previous Landsat missions, allowing for more valuable Earth observations to be added into the USGS Landsat archive.
Visit the Landsat 9 web page for more information.