The sky on
your birthday.
XMM Launched
The X-ray Multi-Mirror Mission, XMM, launched in December 1999, beginning a new era in X-ray astronomy. Its three large telescope barrels hold 58 concentric, gold-plated mirrors to reflect high-energy X-rays. XMM joined NASA's Chandra X-ray Observatory, working together to study phenomena like black holes, active galaxies, and hot gas in galaxy clusters. These instruments allow us to observe the universe in wavelengths invisible to the human eye.
We cannot put this date's photograph on paper at poster size. We can print the nearest public archive plate to your date instead.
See print sizesPrinted, shipped and sold by Zazzle
Released on your day
Space pictures released on your month and day in other years, or a few days either side. Each one is sharp enough to print as a poster.
-
Released on 21 December 2015 SN Refsdal: The First Predicted Supernova Image See it as a poster -
Released on 21 December 2006 Portrait of a dramatic stellar crib* See it as a poster -
Released on 21 December 2022 A Wreath of Star Formation in NGC 7469 See it as a poster -
Released on 21 December 2009 Star Cluster R136 Bursts Out See it as a poster -
Released on 21 December 2023 Webb spots a second lensed supernova in a distant galaxy See it as a poster
In tropical astrology, 21 DEC 1999 falls under Sagittarius (♐). The sign's window runs from 11-22 through 12-21. Sagittarius points straight at the center of the Milky Way, our galaxy's brightest region. The Sun was crossing this region of the sky on 21 DEC 1999.
Questions about December 21, 1999
What space photo was released on December 21, 1999?
NASA's Astronomy Picture of the Day for December 21, 1999 was "XMM Launched". It's the card at the top of this page.
What was the Moon's phase on December 21, 1999?
A full moon, about 97% lit.
What day of the week was December 21, 1999?
December 21, 1999 was a Tuesday, day 355 of the 365 days in 1999.
Was there a meteor shower on December 21, 1999?
Yes: the Ursid shower, peaks tomorrow.
Is it free?
Yes. Seeing, sharing and downloading the card is free, and there's no account to make.