What does this number measure?
NASA's 2025 description places this star-forming region's extent at around 100 ly. Detailed images show portions of it; this reference represents the whole region under that description.
Compare the stated dimensions
The comparison uses the number in each fact sheet: altitude, height, diameter, length or distance, depending on the reference. Two values in metres do not necessarily describe the same property.
Source and limitations
Rounded documentary extent. Boundaries are diffuse and depend on the observations and convention used; this is not a distance from Earth.
Original schematic illustration, not a photograph. Shapes, colours and details are interpreted; only the stated dimension is compared.