NASA’s TOMEX+ Rocket to Track Turbulence at Edge of Space
August 18, 2025

update: The TOMEX+ sounding rocket mission is now targeting no earlier than Thursday, Aug. 21, for the first launch attempt due to cloud cover in the area and high sea states from Hurricane Erin.

The Turbulent Oxygen Mixing Experiment Plus, or TOMEX+, is a NASA sounding rocket mission that will investigate one of Earth’s most turbulent atmospheric regions — the mesopause.
Led by principal investigator Jim Clemmons, a professor of physics and astronomy at the University of New Hampshire, TOMEX+ will open its launch window from NASA’s Wallops Flight Facility on Wallops Island, Virginia, on Monday, Aug. 18.

The mesopause is a region of the upper atmosphere stretching from about 53 to 65 miles (85 to 105 kilometers) in altitude, at the boundary between Earth’s mesosphere and thermosphere.
It is the coldest layer of our atmosphere, where icy noctilucent — or “night-shining” — clouds form and temperatures drop to nearly minus 148 degrees Fahrenheit (minus 100 degrees Celsius).
The mesopause is a mixing ground where weather patterns from the lower atmosphere transfer energy upward into space, fueling turbulence that can increase drag on satellites.
This layer’s role linking Earth to space makes it a priority for research.
But, since the layer spans the Von Kármán line — the theoretical boundary where Earth’s atmosphere transitions to outer space — it is difficult to access, too high for weather balloons and too low for satellites.
Many of its mysteries can only be explored using sounding rockets, which can be precisely aimed to reach specific altitudes.

The TOMEX+ mission will focus on a layer of atomic sodium in the atmosphere that peaks at about 56 miles (90 kilometers) altitude.
This sodium layer forms from the constant influx of dust grain-sized meteors that burn up in the sky.