Instructions for Making a
Color Image of SN 1987A
Select where to point the Hubble
Space Telescope and its Wide Field/Planetary Camera
(WFPC2) in order to make a mosaic.
a blue filter (B) to select only a blue light from
spectrum then expose the WFPC2 detector. Point
the telescope again and repeat. Process these data
and mosaic them into one
black and white image.
(Why does the WFPC2 have an unusual
a visual filter (V).
And then repeat using a red filter
| B filter
| V filter
| R filter
(The color in the background of these icons gives
the range of color transmitted by each filter.)
Check the progress. Assign
the B filter the color blue, the V filter the color
green and the R filter the color red; this is chromatic ordering Combine these 3 different
images to create a 3 color image highlighting the
color of the stars.
Repeat above observations and processing
using a filter which transmits only the green light
of hot oxygen gas ([O III]).
| [O III] filter
Repeat using a filter which
transmits only the red light of hot hydrogen gas
(H II; also called H alpha).
Add the [O III] filter image to
the green image.
Add the H II filter image to the
these blue, green, and red images to create a 3
color image. Adjust the brightness to show both
the stars and the hot gas of the nebula where SN
1987A is located.
Finish off by cropping to show
the supernova in slightly more detail.
For a hardcopy version, copy
and print according to instructions at our
image information pages.