The National Mall in Washington, District of Columbia — The American Northeast (Mid-Atlantic)
Is our Sun a normal star? Stars are great luminous spheres of hydrogen and helium gas held together by their own gravity. Most stars in our galaxy exist in pairs or even in multiple-star systems. So, our singular Sun is relatively unusual.
A binary star is a pair of stars orbiting a common center of gravity. Binary stars can appear as two points of light close together, but not all double stars are binary. Some simply appear close because of Earth's vantage point, but one may be much farther away than the other.
Inside the Observatory
During some evening stargazing programs, you can view such famous double star systems as Albireo in Cynus or Mizar and Alcar in the Big Dipper. Sometimes you can see their difference in color.
This image of the beautiful binary star Albireo was taken at the Public Observatory on March 18, 2015, with the Cook Memorial Telescope.
The central star in the handle of the Big Dipper is actually two stars, Mizar and Alcor. If you have good vision, you can distinguish the double star with the naked eye. Diffraction spikes have been added for emphasis.
Viewing Our Universe:
Smithsonian Astrophysical Observatory
The Smithsonian Astrophysical Observatory (SAO) was founded in 1890 in Washington, D.C. It is now
Some binary stars exchange gas near the end of their lives. The image (top) of the binary star Mira was taken by NASA's Chandra X-ray Observatory. The illustration (bottom) depicts the same star system.
X-ray: NASA/CXC/SAO/M. Karovska et al.
Illustration: CXC/M. Weiss
In 2011 NASA's Kepler spacecraft discovered a planet orbiting a pair of stars. The star system, illustrated here, is called Kepler-16.
←This painting of Mira by Chesley Bonestell depicts the view from a hypothetical planet orbiting the pair of stars. The background star is a bloated red giant, while the other is a dense, hot white dwarf.
How to Learn More:
Erected by National Air and Space Museum.
Location. 38° 53.274′ N, 77° 1.109′ W. Marker is in The National Mall, District of Columbia, in Washington. Marker can be reached from Independence Avenue Southwest west of 4th Street SW, on the right when traveling west. Touch for map. On the grounds of the National Air and Space Museum on the side of the Phoebe Waterman Haas Public Observatory. Marker is in this post office area: Washington DC 20024, United States of America.
Other nearby markers. At least 8 other markers are within walking distance of this marker. Saturn (here, next to this marker); Moon (here, next to this marker); Phoebe Waterman Haas (here, next to this marker); Jupiter (here, next to this marker); Venus (here, next to this marker); Star Nurseries (here, next to this marker); Cook Telescope (here, next to this marker); Sun (here, next to this marker). Touch for a list and map of all markers in The National Mall.
Categories. • Air & Space •
Credits. This page was last revised on December 15, 2017. This page originally submitted on December 12, 2017, by Devry Jones of Washington, District of Columbia. This page has been viewed 91 times since then and 20 times this year. Photos: 1, 2. submitted on December 12, 2017, by Devry Jones of Washington, District of Columbia. • Bill Pfingsten was the editor who published this page.