At the Pine Mountain Observatory Teacher’s workshop this summer I am having each teacher make their own sewing needle spectroscope to observer the absorption lines in the Sun. The simple sewing needle Sun spectroscope takes less than three minutes to make and it eaisly shows the Fraunhofer absorption lines for F, b4-1, E, D3-1 and C.

The below Sewing Needle Sun Spectroscopes are made with two different type of sewing needles. The Dritz 56D sewing needle is larger diameter and has more scratches. The Dritz 6834 sewing needle is smaller diameter and is more smoother but it bends very easy.

• 1 sewing needle
• 1 black paper 12" x 4"
• 1 Rainbow Symphony grating glasses Linear 500 Line/MM or use CD-ROM with covering removed by air compressor or by tape.
• Tape

Making the Sewing Needle Sun Spectroscope

• Fold the black paper three times.
• Push the sewing needle through the black paper.

• Put tape over the sewing needle tip.

Using the Dritz 56D Sewing Needle Sun Spectroscope

• The Sun is to the left.
• The fold creates a shadow to better see the spectrum.
• Photo taken with Nikon D70 DSLR with Rainbow Symphony 01505 - 500 lines per m/m diffraction grating film over the lens.
• Sewing needle is Dritz 56D 6 Soft Sculpture Doll, Size/Tam 3 inches (76mm) and is 0.038 dia.
• The horizontal lines are from the sewing needle scratches.
• The vertical lines are Fraunhofer absorption lines

• Full resolution image cropped.

Using the Dritz 6834 Sewing Needle Sun Spectroscope

• The Sun is to the left.
• The fold creates a shadow to better see the spectrum.
• Photo taken with Nikon D70 DSLR with Rainbow Symphony 01505 - 500 lines per m/m diffraction grating film over the lens.
• Sewing needle is Dritz 6834 6 Basting Needles, Size/GR/Tam 7 and is 0.027 dia.
• The black paper bends the sewing needle so that there is a bright reflection spot on the needle.
• The horizontal lines are from the sewing needle scratches.
• The vertical lines are Fraunhofer absorption lines

• The top spectrum image is full resolution image cropped.
• The Basting Needle is smoother than the Sculpture Doll Needle.
• The second from the top spectrum image is cropped for processing with ImageJ.
• The bottom spectrum image is an average of the columns, resized to 100 pixels high and is not sharpen.
• labels added from Wikipedia Fraunhofer lines.
• Easy Fraunhofer lines identified in the spectrum image.
  • H, G, f, e, F, c, b4-1, E, D3-1 and C
• Easy Fraunhofer lines identified using the spectrum glasses.
  • G, F, c, b4-1, E, D3-1 and C

• Screwdriver CD Spectroscope
• Identifying Lines in the Solar Spectrum by Universitiy of Washington.
• The Solar Atmosphere
• The Sun's Fraunhofer Lines
• The Most Intense Solar Fraunhofer Lines

© 1998-2011 David Haworth