I am a retired geologist and have recently taken up astronomy and astrophotography as a hobby. As is clear from the course there is a close association between the two sciences and I was keen to learn more. This is my fifth astronomy MOOC and by far and away a country mile the best; how many of those in a parsec?.

Apart from the sheer breadth of subject matter covered I particularly liked the way various maths formulae (not too difficult) were explained and gradually used to explain and link various aspects of astronomy - thus adding weight to the explanations and especially how it all elegantly fits together. If you want to do just one course to understand astronomy, this is the one.

Many thanks to David and team for the high quality of lectures and diagrams etc. which thoroughly backed up the lectures + the interviews provided insight form other experts in their respective fields.

If you're ever in the UK do look me up - I also cycle and would love to go on a ride and talk astro etc. Thanks again to all.

Here's my website if you're interested: https://watchthisspaceman.wordpress.com/

I took this course completely for fun, so did not complete any assignments, but I want to say that I enjoyed it immensely! Our lecturer brought immense enthusiasm to the rather heavy topic of astronomy and physics and managed to make it reasonable even to those of a non-science background (like me!). The people interviewed also brought very unique views and experiences to the subject, and gave us a good first hand account of what it is like to research and work on NASA projects and other spacefaring missions. Thank you to everyone who made this happen, I hope many other students share the same satisfaction from taking this online course!

This was a very interesting class taught in such a manner that an undergraduate student majoring in any area would find interesting and educational, their is very much to learn for anyone

This is simply fantastic! Such a charismatic lecturer leading us so professionally through heavy subjects in a light manner! Looking forward to more courses!

"Imagining Other Earths" introduces one to astonishing aspects of planetary science, delivered expertly by David Spergel, Charles Young Professor of Astronomy on the Class of 1897 Foundation and Chair. I found the course to be invaluable in improving my understanding of the universe in which we live. Professor Spergels unassuming, inimitable style of delivery leads one to an easy understanding of complex concepts. I found the Professor and the scientists who spoke with him in interviews which supported the lectures to be inspiring. I commend this course to anyone who is interested in understanding the universe.

The best course ever.! it really has the scientific detail that you do not find anywhere else in a clear simple and didactic way. The instructor is an amazing educator.

Thorough, lengthy, weeks-long grounding in the subject. Only problem is stupid peer review.

I cannot say enough about this wonderful class. I am a senior in high school and have never taken a class on astronomy or anything of the sort, so I was quite nervous heading into this course. Professor Spergel explains things so clearly and all the presentations were executed very well! This class is a perfect course for those wanting to learn more about our universe, it is not unbelievably difficult but still challenging enough to work your brain and expand your knowledge. I love this class! Thank you Professor Spergel, I will never forget this course.

This is a wonderful course, even for somebody, such as myself, who tends to freeze in terror when presented with mathematical equations of any sort. I'm a linguist, artist and musician, so no physicist, and yet have found here a wealth of imagination and knowledge that is accessible, even if only at the broadest level, to anyone, regardless of their academic background. Highly recommended.

Excellent course, you learn a lot of things. Professor David Spergel is really interesting and exciting,

I am really grateful for all that I have learned during this course.

Excellent cours, vous apprenez plein de choses. Pr David Spergel est très intéressant et passionnant.

Je lui suis très reconnaissant pour tout ce que j'ai appris durant ce cours

This class was an exceptional journey into the world outside our own - and the details, balance, and intricacies of an ever changing universe. Professor Spergel is an incredible asset to the world of astrophysics and I feel truly lucky that he took the time to teach us. I happily anticipate leaning even more on this fascinating subject.

In this course unlike routine things like Big bang,Solar system,Galaxies and so on,I learnt new things such as Habitable zone and Goldilocks,Exoplanet zoo,Concept of light,Evolution,Quantum mechanics,synthesizing of life and Fermi paradox. The interviews of eminent scientists are very very useful.Over all it is very good course.

A great course, a big variety of fascinating topics, interesting and lively explanation of prof. Spergel, great interviews with specialists on many of the topics.

Just one thing I miss in the course, it would be nice to check my understanding of the explanation in quizes.

Nonetheless, great thanks for the course!

A fantastic content that helps you easily understand difficult concepts for the uninitiated in the field. A highly recommended experience. To improve only ask for more interviews with professionals who are now investigating the matter.

Thank you very much for the effort.

I learned a lot on this course in a fun and meaningful way. Lectures are interesting and even humorous at times :) Took me a while to complete it but I'm happy that I did. Thank you for all the time and effort pout into this course!

This was my first coarse on Coursera, and it is an amazing coarse. The professor and the presentation are so vividly unique, even as a high school sophomore, I was able to understand a large part of it.

Really enjoyed the course. It gave a very comprehensive introduction to Astrobiology and I enjoyed being pushed to write a science fictional short story at the end.

Outstanding course for anyone interested in astronomy and the search for extra-solar planets. The instructor is a world-class scientist and a great teacher.

I have no professional interest in this course but watch the videos in my freetime. This should tell you everything about how good this course is.

Excellent course with a lot of information served in the context and furthermore in the most understandable way.

Thanks for it.