Astronomy/Midnight in Paris


Dear Mr. Philip,

I was wonder if see the star/ constellations in the skies  of Paris for example in Jan 1, 2013.

Would we be able to see the same or similar stars/constellation where I live in Japan? I believe Paris and another city in Japan have a very similar longitude.

What would be the time gap before we see the same stars/constellation in Japan.

Would really like to know the answer and Thank you in advance.


Paris is at approx. 49 degrees North latitude while Tokyo is at 35 N. So Tokyo is considerably further south. Hence, some of the (more southerly constellation) stars visible in Tokyo will appear to be shifted out of view in Paris. (Of course, if one compared the stars visible in Paris to the tip of Japan's most northerly island, Hokkaido- at about 44N, these differences would be less- so nearly all the stars seen in Hokkaido would also be seen in Paris.

Re: longitude difference, Paris is at roughly 2 E longitude while Tokyo is at approx. 140 E, so there is a difference of about 138 degrees. Since there are 15 degrees of longitude per hour of (mean solar) time, this translates into a time difference of about:

138/ 15/h =  9.2 hours.

Thus, you'd see those constellations-stars I identified above roughly 9.2 hrs. later in Japan. So, if a given star is visible at 7.30 p.m. local mean solar time in Paris, you'd see it at roughly 4.45 a.m. in Japan.

Hope this helps!


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Philip Stahl


I have more than forty years of experience in Astronomy, specifically solar and space physics. My specialties include the physics of solar flares, sunspots, including their effects on Earth and statistics pertaining to sunspot morphology and flare geo-effectiveness.


Astronomy: Worked at university observatory in college, doing astrographic measurements. Developed first ever astronomy curriculum for secondary schools in Caribbean. Gave workshops in astrophysics and astronomical measurements at Harry Bayley Observatory, Barbados. M.Phil. degree in Physics/Solar Physics and more than twenty years as researcher with discovery of SID flares. Developed of first ever consistent magnetic arcade model for solar flares incorporating energy dissipation and accumulation. Develop first ever loop solar flare model using double layers and incorporating cavity resonators.

American Astronomical Society (Solar Physics and Dynamical Astronomy divisions), American Mathematical Society, American Geophysical Union.

Solar Physics (journal), The Journal of the Royal Astronomical Society of Canada, The Proceedings of the Meudon Solar Flare Workshop (1986), The Proceedings of the Caribbean Physics Conference (1985). Books: 'Selected Analyses in Solar Flare Plasma Dynamics', 'Physics Notes for Advanced Level'. 'Astronomy and Astrophysics: Notes, Problems and Solutions'.

B.A. Astronomy, M. Phil. Physics

Awards and Honors
American Astronomical Society Studentship Award (1984), Barbados Government Award for Solar Research (1980), Barbados Astronomical Society Award for Service as Journal Editor (1977-91)

Past/Present Clients
Caribbean Examinations Council, Barbados Astronomical Society, Trinidad & Tobago Astronomical Society.

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