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Lecture
Notes |
Welcome to the new term and to the course Highlights of Astronomy!
We started on Chapter 1. It is advised to be prepared for the lectures by reading the material that will be covered in class in advance. Please read all of Chapter 1. We learned about a scaled version of the solar system where the sun is shrunk to the size of 1 cm. Do you remember where the planets are located in such a scaled-down solar system and how big they are? We were introduced to the power of 10 notations and to constellations. Click here for likely the worlds earliest astronomical engraving. We learned about the geocentric equatorial coordinate system used for giving positions of celestial objects (right ascension :RA, declination: dec. or decl.). We learned about different time definitions and visualized the vernal equinox. We also learned about the precession of the spin axis of Earth.
14 January 2021
We learned about the ecliptic, equinoxes and solstices.
19 January 2021
We looked at the moon and its orbit around Earth. We tried to understand the eclipse of the sun and the lunar occultation.
20 January 2021 tutorial
21 January 2021
We learned about the motion of planets and how Ptolemy interpreted the retrograde motion of Mars. Then Copernicus
introduced the heliocentric system. Do you remember how he computed the sidereal orbital period of a planet? Kepler introduced his three laws.
Do you remember the three laws? We learned about Galileo's discoveries of the phases of Venus and four moons of Jupiter. Do you remember
how these discoveries supported the heliocentric view of the orbits of planets. Then Newton "invented" the force. He introduced his three laws and the universal law of gravitation. While Kepler's third law is only applicable for orbits around the Sun, Newton's equivalent law is applicable everywhere in the universe. Do you remember how P is related to a? We started on Chapter 3.
22 January 2021
Observations with the 1m reflector of York's Allan I. Carswell Observatory
26 January 2021
We continued with Chapter 3 and covered the sections on the telescopes and the electromagnetic spectrum.
27 January 2021 Tutorial and observations with the 1m reflector of York's Allan I. Carswell Observatory
28 January 2021
We learned about blackbody radiation and computed the luminosity of the Sun. We also derived the solar constant.
2 February 2021
We finished Chapter 3.
3 February 2021
4 February 2021
We learned about the formation of the solar system in Chapter 4. We covered part of the exoplanets in Chapter 5. Click here for a list of habitable exoplanets. Click here for search of other exoplanets. Click here for 20 intriguing exoplanets.
9 February 2021
We learned about the most important aspects of Earth as a planet and looked in particular at some characteristics of Earth, for instance the distance from the Sun, its average mass density and how that relates to our understanding of the interior of Earth, the magnetic field, continental drift and the atmosphere. We computed the mean temperature of a planet and took as an example Earth. What would the temperature of earth be if Earth did not have an atmosphere? Then we focused on the Moon and its origin and learned about the tidal forces and their strong inverse relation with the distance of two objects. How do tidal forces affect the spin of the Earth and the distance of the Moon from earth?
11 February 2021
Then we covered Mercury and Venus. We learned about Mercury's origin and the particular 3-2 spin orbit coupling. We looked at Venus in detail, its atmosphere and its surface and learned about the enormous greenhouse effect on that planet.
23 February 2021
Then we talked about Mars and that it is snowing on Mars as discovered with York's lidar system installed on the Phoenix lander. We had a discussion about whether it would be attractive to go on a one-way mission to Mars as it was conceived in the Mars One mission. We learned about the three missions this year to Mars by the US, China and UAE, and about the success of the landing of Perseverance on the surface of Mars on 18 February 2021. Here you can find the list of missions to Mars. Click here for a beautiful panoroma view of Mars from the Curiosity mission. We are now on p. 189.
25 February 2021
We started on Chapter 7 and talked about Jupiter and its moons. We also computed the impact energy release of chunks of
comet Shoemaker Levy crashing into Jupiter in 1994. We learned about the four Galilean satellites of Jupiter.
2 March 2021
We had our midterm exam.
4 March 2021
We looked at Saturn, Uranus and Neptun and studied two moons in particular. Then we turned to the dwarf planets and small solar system bodies. We learned about Pluto and the other "vagabonds" of the solar system. Where are Voyager 1 and 2 now?
9 March 2021
Of particular interest is the recently discovered body "Oumuamua," the first known interstellar object to visit our solar system. We are now on p266.