Examlex
List the three types of binary stars.
1930s
A decade marked by the global economic downturn known as the Great Depression, significant political changes, and the lead up to World War II.
Presidential Campaigns
The process by which candidates for the presidency of a country promote themselves and their policies to the electorate to win votes.
Barack Obama
The 44th President of the United States, serving from 2009 to 2017, and the first African American to hold the office.
Donald Trump
The 45th President of the United States, known for his business background and controversial presidency.
Q5: If two stars are emitting the same
Q7: Gentle gravitational tidal forces appear to be
Q13: Compared to other spiral galaxies, the Milky
Q18: How have astronomers determined the mass of
Q22: Because of the period-luminosity relation for Cepheids
Q24: The upper chromosphere is hot enough to
Q25: Astronomers refer to the dark center of
Q28: Absolute visual magnitude is calculated at a
Q47: Kepler's first law of planetary motion states
Q60: A star with a mass of 10