Astr 121 - Study guides, Class notes & Summaries

A crescent moon is visible in the northern hemisphere, with the crescent shape on the right side of the Moon. This phase is called: - ️️Waxing crescent A lens ___ light to converge at a point - ️️Refracts A magnetic field line pokes through the Sun's photosphere inhibiting convection and cooling that location. What feature is observed in that location on the photosphere? (Also describe how the other features are formed) - ️️Sunspot A mirror ___ light to converge - ️️Reflects ...

A human being is the size of what kind of light? - ️️Radio A low pressure region in Jupiter's southern hemisphere moves - ️️counter-clockwise A neon light produces what kind of spectrum? - ️️emission spectrum A new planet Vulcan is discovered that is always on the opposite side of the Sun from the Earth. Which of the following is true a) its orbital period is 1 year b) its distance to the Sun is 2 A.U. c) it never transits the Sun d) a and c e) all of the above - ️️a and...

According to Alfred Weneger, which of the following is evidence of Continental Drift? Select all that apply. a. Mass extinction at several points in Earth's history b. Ice Ages c. Similar glacial scrapes in different continents d. Steady Global Warming e. Impact craters scattered all around the world f. Tropical plant fossils in Greenland. - ️️c. Similar glacial scrapes in different continents f. Tropical plant fossils in Greenland. Auroras on planets are generated from... ...

Perihelion - ️️when the earth is closest to the Sun on its orbit Leap year - ️️an extra day to help synchronize calendar with seasons Math: Is the year divisible by 4? yes: Is the year divisible by 100? Yes: its a leap year No: is it divisible by 400? Yes: it is a leap year Spring Tides - ️️more extreme tides happen when new moon/full moon (Moon and Earth lineup) Lunar eclipse - ️️sun is eclipsed by the Earth, casting a shadow on the Moon Earth completely bloc...

__ is the time for earth to rotate once; ___ is the time for the moon to orbit the earth once; ___ is the time for earth to orbit the sun once - ️️day, month, year ___ appear to move among the "fixed" stars over longer times. In ancient greece, they called these ___, or ___. They lie close to the ___. - ️️moon and planets, wandering stars, planets, ecliptic A crescent moon is visible in the northern hemisphere, with the crescent shape on the right side of the Moon. This phase is ca...

According to Hubble's Law, if two galaxies are not part of our Local Group, and galaxy B is three times farther away from us as Galaxy A, then Galaxy B will - ️️ove away from us three times faster than A According to our current understanding, giant elliptical galaxies form: - ️️by the merger (or swallowing) of a number of smaller galaxies in a cluster of galaxies According to the models of the universe we discussed in this course, why do the galaxies move apart (why do we have Hubble...

about 91% (by number) of the atoms in the sun are the element - ️️hydrogen Age of the Universe - ️️13.7 billion years all the energy of the sun is generated in the - ️️core alpha particle - ️️A cluster of 2 protons and 2 neutrons emitted from a nucleus in one type of radioactivity an astronomer discovers a new star and wants to measure its temperate. she could do this by: - ️️take a spectrum of the star and determine the spectral type Astronomers did star counts in all d...

(In the absence of a strong magnetic field), what is the chief factor that determines what type of electromagnetic radiation objects give off: - ️️their temperature A college friend of yours who has been postponing taking any science courses hears you talking about the generation of nuclear energy in the Sun and makes the following observation: "The whole idea of the atomic nucleus is pretty ridiculous. If an oxygen nucleus consists of eight protons and eight neutrons, the charge on that n...

A charming friend of yours who has been reading a little bit about astronomy accompanies you to the campus observatory and asks to see the kind of star that our Sun will ultimately become, long, long after it has turned into a white dwarf. Why is the astronomer on duty going to have a bit of a problem satisfying her request? - ️️after a white dwarf cools off it becomes too cold and dark to emit visible light A group of graduate students, bored during a cloudy night at the observatory, begin...

A human being is the size of what kind of light? - ️️radio A neon light produces what kind of spectrum? - ️️emission spectrum A new planet Vulcan is discovered that is always on the opposite side of the Sun from the Earth. Which of the following is true - ️️its orbital period is 1 year it never transits the sun A planet has an angular size of 20 degrees. If the planet moves twice the distance away, its angular size will be - ️️10 degrees A rocket on a Hohmann orbit from Eart...