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“Bite-Size Bits of Local, National, and Global History”
The National Mall in Washington, District of Columbia — The American Northeast (Mid-Atlantic)
 

Asteroids and Comets

 
 
Asteroids and Comets Marker image. Click for full size.
By Devry Becker Jones, November 14, 2017
1. Asteroids and Comets Marker
Inscription.
You are standing in the "asteroid belt," a region between the orbits of Mars and Jupiter where countless rocks called asteroids orbit the Sun. Every so often icy body called comets pass through this region on their way to the inner solar system.

You are walking through a scale model of the solar system. The real solar system is 10 billion times larger. At this scale even the largest asteroids are too small to be seen. Look at the map below to see where you are.


Voyage to an Asteroid
Welcome to Ida, a medium-sized asteroid about 40 miles (60 km) across. The little object is Dactyl, Ida's moon. Gravity is so weak on Ida that you could easily jump as high as the Washington Monument.

Home of the Asteroids
A million asteroids larger than half a mile (0.8 km) across can be found here in the asteroid belt, but they are so spread out that this space is mostly empty.

Long known as the largest asteroid, Ceres is 580 miles (940 km) across. In 2006, it was renamed a "dwarf planet."

Voyage to Halley's Comet
Every 76 years, Halley's Comet journeys from beyond Neptune into the inner solar system. Once inside the orbit of Jupiter, solar heat begins vaporizing ice on the surface of this large dirty snowball the size of a city. The solar wind
Asteroids and Comets Marker image. Click for full size.
By Devry Becker Jones, November 14, 2017
2. Asteroids and Comets Marker
and sunlight sweep ejected gas and dust into 2 majestic tails, which can grow nearly long enough to span the distance between Earth and the Sun. Halley's Comet returns in 2061.

The Outer Boundaries of the Solar System
The solar system may contain a trillion comets, but very few venture inside the orbit of Neptune. On the scale of this model solar system, comets could be found up to 900 miles (1,500 km) from where you are standing.
Walk to Jupiter about 55 steps.

Imagine
When passing the Sun, some comets travel fast enough to go from New York to California in 18 seconds.

Walk to Mars about 28 steps

Voyage is an exhibition of the National Center for Earth and Space Science Education and the Smithsonian Institution. It is designed for permanent installation in communities worldwide.
 
Erected 2013 by Smithsonian Institution.
 
Location. 38° 53.32′ N, 77° 1.139′ W. Marker is in The National Mall, District of Columbia, in Washington. Marker is on Jefferson Drive Southwest 0.1 miles west of 4th Street SW, on the left when traveling west. Touch for map. On the grounds of the National Air and Space Museum. Marker is in this post office area: Washington DC 20565, United States of America.
 
Other nearby markers. At least 8 other markers are within walking distance of this marker. Mars (a few steps from this marker); Earth (within shouting distance of this marker); Venus (within shouting distance of this marker); Mercury (within shouting distance of this marker); Sun (within shouting distance of this marker); Voyage (within shouting distance of this marker); Jupiter (within shouting distance of this marker); T.S.C. Lowe's Observation Flight (within shouting distance of 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 November 18, 2017. This page originally submitted on November 14, 2017, by Devry Becker Jones of Silver Spring, Maryland. This page has been viewed 69 times since then. Photos:   1, 2. submitted on November 14, 2017, by Devry Becker Jones of Silver Spring, Maryland. • Bill Pfingsten was the editor who published this page.
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