Test 11, Chapter 11 Flashcards
in which climate zone does every location have at least one day a year when the sun is directly overhead?
tropics
which method of measuring time uses time zones?
standard solar time
what type of time is based on the stars?
sidereal time
the point on the celestial sphere directly above an observer is called the
zenith
what was the first artificial satellite of Earth?
Sputnik 1
what was the first satellite launched by the US?
Explorer 1
what circle on the celestial sphere runs directly overhead and through the celestial poles?
meridian
the path the sun follows in a year
ecliptic
a device that splits light into a spectrum for analysis
spectroscope
what system of timekeeping divides the day into hours AM and PM?
12 hour time
the equation of time is the relationship between mean solar time and
apparent solar time
what term refers to an unmanned spacecraft launched specifically to explore the unknown?
space probe
what are the two points on the path of the sun at which the sun is farthest from the celestial equator?
solstices
in what type of orbit does a satellite stay above the same point on the Earth’s surface?
geostationary orbit
which calendar system is now used in most nations?
Gregorian calendar
what term refers to the earth’s slow “wobble” on its axis that causes the pole star to change?
precession of the equinoxes
what visible-light telescope was launched into space in 1990?
Hubble Space Telescope
what unit of time is based on the period Earth takes to orbit the sun once?
solar year
used to study the heavens
astronomical satellite
perform a variety of functions, such as making maps, forecasting crop production, spotting forest fires, and surveying cities
Earth observation satellite
relay telephone conversations and radio and television broadcasts
communications satellite
include the satellites of the Global Positioning System
navigational satellite
a telescope that uses a mirror as the objective is a _____ telescope
reflecting
the abbreviation A.D. stands for
anno Domini
the technique in which computer-controlled mirrors constantly flex and bend to correct for atmospheric distortion is
adaptive optics
when white light shines through a gas and then passes through a prism, the broad spectrum of color will show narrow, dark lines called
absorption lines
the mean solar time at Earth’s prime meridian is called
UTC (coordinated universal time)
a circumpolar star that crosses the meridian between the visible celestial pole and the horizon is making a ____ transit.
lower
in which type of orbit does a satellite cross the equator at the same local mean solar time on every orbit?
sun-synchronous orbit
which type of orbit would a spacecraft use to increase its altitude?
Hohmann transfer orbit
from which calendar do the English month names come?
Julian
what was the first space station designed so that it could be expanded?
Mir
what astronomical event marks the beginning of winter in the Northern Hemisphere?
December solstice
what US space program landed a man on the moon?
Apollo
At an altitude of 500 miles above the earth, a satellite with a speed of 16,700 mph will have a circular orbit. What describes the orbit of a satellite at an altitude of 500 miles and a speed of 17,100 mph?
the satellite will have an elliptical orbit with the lowest point at 500 miles and the highest point above 500 miles.
what rocket design did the US use to launch manned moon missions?
Saturn V
what term refers to the highest point of the orbit of an earth-orbiting satellite?
apogee
what part of a telescope collects the light?
objective
the term that refers to the speed a spacecraft must be traveling at to leave Earth’s gravity without using its rockets anymore is
escape velocity
the unit of time, larger than a day, that is not based on the motion of a heavenly body
week
the first type of spacecraft designed to be reused was the
space shuttle
a rocket that can be stored for years with the fuel loaded is a _____ rocket
solid - fuel
scientists can use multiple radio telescopes to produce images more detailed than possible with a single radio telescope by using the technique called
interferometry
the two points at which the path of the sun crosses the celestial equator are called
equinoxes
the two basic kind of optical telescopes are
refracting & reflecting
first American in space
Alan Shepard
first woman in space
Valentina Tereshkova
Father of Modern Rocketry
Robert Goddard
first man in space
Yuri Gagarin
first American to orbit the earth
John Glenn
German-born engineer who became the US top rocket designer
Wernher von Braun
first man to set foot on the moon
Neil Armstrong
Explain why the Julian and Gregorian calendars have leap years and contrast how these calendars determine which years are leap years.
Leap years are needed because there is not a whole number of days in a solar year.
In the Julian calendar, every forth year is a leap year.
The Gregorian calendar’s major difference from the Julian calendar is the elimination of leap years for all century years except those evenly divisible by 400.
