YorkUniversity Faculty of Science
Department of Physics and Astronomy
PHYS 2070 3.0 W14/15 Galaxies
and the Universe
6 January 2015 Welcome to the new term and to the
course Galaxies and the Universe!
Please go to
www.yorku.ca/prs to register your clicker.
Unfortunately I have to be out of town this
first week. Please read Chapter 17 of the book UNIVERSE. Please also
familiarize yourself with the blue lab book "Observational Project."
We started on Ch. 17 and covered material up to p. 469 of
"Universe" 10th edition.
At the beginning of class each student was assigned a galaxy for
the observing project. Then we covered material up to p
486. We calculated the luminosity of the sun from the solar constant.
We talked about Wien's law, and the Stefan-Boltzmann constant and
figured out how to determine the radius of a star. We started on the
HR- diagram. At the end we had our first quiz. Please be prepared for the Observatory
training. Look at the youtube videos. You can search for yorku
observatory or go to the links on the phys2070 website. 20 January
Today we had our observatory training session. The training
session is mandatory for anybody of the class to use the telescope.
After the training session we continued with the course. We covered the
radius determination and are now on p. 489.
We are meeting in LSB 108 (computer lab in Lumbers) to get
instructions for using the software package IRAF for the analysis
of the CCD images of the project for the course. Please make sure that
you have activated your account on 22 January on cosmos by going to
then find Manage My Services
and click on Activate Cosmos Account
We learned about how the mass of stars is determined if the stars are
members of a binary system. Then we looked at
masses of main sequence stars and the mass to luminosity relation for
these stars. We are now on p. 504.
We started with Chapter 18. We looked at reflection nebula, emission
nebula and dark nebulae. We looked at the birth of stars
and followed the birth evolution through tracks in the HR diagram. Jets
can emanate from protostars and end in Herbig Haro objects.
3 February 2015
We started with Chapter 19. We talked about the evolution of a cluster,
population I and II stars, Cepheids.
5 February 2015
We talked about close binaries and how each of them affects the
evolution of the other. Then we started with chapter 20.
We covered the evolution of stars with masses from 0.4 to 2-3 Msol.
Fusion of He, helium flash, horizontal branch, AGB,
planetary nebula, white dwarf, brown dwarf. We are now on p. 575.
10 February 2015
We covered WDs and supernovae. We learned about SNIa, Ib, Ic and
SNII. Do you remember which are core-collapse SNe and
which are thermonuclear detonation SNe?
12 February 2015
Today we learned about neutron stars, their escape velocity and
how they are related to pulsars. All pulsars are NS, but not all NS
are pulsars, only those that we see in the form of pulsed radiation. We
are now on p. 602.
24 February 2015
We learned about black holes, special relativity and general
relativity. What does it mean if space is bent and warped?
26 February 2015
We had our midterm exam. 17 March 2015
We talked about the midterm exam. We saw the movie "Testing Einstein's
2015 We finished Chapter 21 and are
now on p 633.
24 March 2015
We talked about our own Galaxy.
2015 We finished Chapter 22. In
particular we learned about the detection of radio waves from the
Galactic Center by Karl Jansky.
We looked at the Galactic Center in the radio and learned about
synchrotron radiation. Then we saw an animation of the stars
orbiting our Galaxy's supermassive black hole. We computed the mass of
the black hole. Do you remember what the mass is?
We then started on Chapter 23, learned about Hubble and his distance
measurement of galaxies with Cepheids and the classification scheme of
galaxies. We are now on p 677.
31 March 2015
We learned about the Hubble law, redshift and the expansion of
2 April 2015
Rotation curves of other galaxies also indicate the presence of dark
7 April 2015
We looked at quasars and active galaxies and learned about
superluminal expansion velocities of jets in quasars.
9 April 2015 We learned about the CMB, the
evolution of the Universe and that the Universe is accelerating.
14 April 2015 We learned about the amazing
theories about the evolution of the Universe from 10-43 s to
Inflation , inflation, inflation... and then the miniscule temperature
variations of the CMB leading to our present
16 April 2015
We started with finishing Chapter 26. We then focused on
habitable zones on the Galaxy and in a region around stars.
Then we looked at communication aspects with hypothetical alients and
learned that we have not yet got contact to them.
But who knows what the future will bring??? And that was the end of the
course. See you for the final exam in ACW 005
on 20 April 2015 from 2:00 pm to 5:00 pm.