Caption
This 2023 image of Wolf-Rayet 140, a system of dust shells ejected by two massive stars at the center, was captured by the James Webb Space Telescope’s MIRI (Mid-Infrared Instrument).
The image shows a scale bar, compass arrows, and color key for reference.
The scale bar is labeled in light-years along the bottom, which is the distance that light travels in one Earth-year. One light-year is equal to about 5.88 trillion miles or 9.46 trillion kilometers. The scale bar is also labeled in arcminutes, which is a measure of angular distance on the sky. One arcsecond is equal an angular measurement of 1/3600 of one degree. There are 60 arcminutes in a degree and 60 arcseconds in an arcminute. (The full Moon has an angular diameter of about 30 arcminutes.) The actual size of an object that covers one arcsecond on the sky depends on its distance from the telescope.
The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above).
This image shows mid-infrared wavelengths of light that have been translated into visible-light colors. The color key shows which MIRI filters were used when collecting the light. The color of each filter name is the visible-light color used to represent the infrared light that passes through that filter.
