Astronomy Picture of the Day · April 3, 1999

The Radio Sky: Tuned to 408MHz

The Astronomy Picture of the Day for April 3, 1999 is “The Radio Sky: Tuned to 408MHz,” an image. It is credited to Credit: C. Haslam et al., MPIfR, SkyView. The original explanation runs about 167 words.

From the explanation

“Tune your radio telescope to 408MHz (408 million cycles per second) and check out the Radio Sky! You should find that frequency on your dial somewhere between US broadcast television channels 13 and 14.”

— APOD editors, April 3, 1999

Read the full explanation on science.nasa.gov

At a glance

Date: April 3, 1999
Type: Image
Credit: Credit: C. Haslam et al., MPIfR, SkyView
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 167 words

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On this day: April 3 in other years

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Source

Astronomy Picture of the Day, April 3, 1999 — science.nasa.gov/image-article/apod-1999-april-03-the-radio-sky-tuned-to-408mhz

Copy taken Oct 28, 2026, 2:39 AM EDT. The image and explanation belong to their creators. OpenOrbit is not affiliated with or endorsed by NASA.