1919 Cosmic Times
This poster is the first edition of the Cosmic Times, with the publication date chosen to coincide with the announcement of the first test of Einstein's General Theory of Relativity. Einstein published the theory in 1915, but the first test supporting General Relativity was announced in 1919. In fact, it was this test of General Relativity that really propelled Einstein to "rock star" status.
1919 Article Overview
Age of Universe: Infinite
Size of Universe: 300,000 Light Years
| Article |
Thread |
Summary |
| Sun's Gravity Bends Starlight |
Expanding Universe |
Observations of stars near the Sun during the eclipse of 1918 show that
the starlight bends just as predicted by General Relativity. |
| Sidebar: Why a Total Eclipse? |
-- |
Describes why observers needed a solar eclipse to make observations of
starlight bending around the Sun. |
| Mount Wilson Astronomer Estimates Milky Way Ten Times Bigger Than Thought |
Size of the Universe |
Astronomer Harlow Shapely finds that the Milky Way is 10 times bigger
than previous measurements, using the period-luminosity relationship for
Cepheid variables as discovered by Henrietta Leavitt. |
| Expanding or Contracting? |
Expanding Universe |
Einstein's theory of General Relativity predicts that the Universe
cannot be static – it must be expanding or contracting. Einstein adds the
"Cosmological Constant" to keep the Universe static. |
| In Their Own Words |
-- |
Snippets of papers published by other astronomers during this time. The
snippets highlight the Cepheid period-luminosity relationship, redshift of
galaxies, and the nature of spiral nebulae. |
1919 Lesson Overview
| Activity |
Summary |
Grade |
Discipline |
| |
|
MS |
HS |
|
| 1. Einstein and His Times |
Students look at other 1919 events to decide if Einstein should be
elected "Man of the Year" |
x |
x |
Multidisciplinary |
| 2. Eclipses and Moon Phases |
Students explore how eclipses happen and why Einstein needed a total
eclipse to image stars near the Sun. |
x |
|
Earth Science, Physical Science |
| 3. Two Versions of Gravity: Newton and Einstein |
Students explore the differences between Einstein and Newtonian gravity
through an information exchange. |
|
x |
Physics, Astronomy |
| 4. Einstein's Gravity |
Students use hands-on demonstration to understand how General Relativity
explains gravity and explores Einstein's theories through outside
research. |
|
x |
Physics, Astronomy |
|
