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09/16/2019 – Ephemeris Extra – I’ll be giving my presentation “Apollo and the Moon Race” tonight

September 16, 2019 Comments off

I’ll be giving my illustrated talk Apollo and the Moon Race tonight at 7 p.m. at the Traverse Area District Library on Woodmere Avenue in Traverse City.  The 1960s were a heady time with the space race between the US and the USSR in achieving space firsts.  I will look at the competition, and the incremental steps that had to be made to finally send astronauts to the surface of the Moon on July 20th 1969.

If you miss this presentation, there will be another on Friday September 27, at 7 p.m. at the Betsie Valley District Library in Thompsonville.

Both events will have viewing of the skies with the Grand Traverse Astronomical Society including Jupiter and Saturn afterward if it’s clear.

 

 

09/16/2019 – Ephemeris – Astronomers view a supernova that completely destroyed its star

September 16, 2019 Comments off

Ephemeris for Monday, September 16th. Today the Sun will be up for 12 hours and 29 minutes, setting at 7:51, and it will rise tomorrow at 7:23. The Moon, 2 days past full, will rise at 9:21 this evening.

When a star explodes in a supernova due to being very massive, it generally leaves a tiny compact remnant called a neutron star or a black hole within an expanding cloud of gas and dust. However in the early universe there was only hydrogen and helium. It turns out that stars could get much more massive, maybe several hundred times the mass of the Sun, rather than tens of times more massive that the Sun that exist now. Theoreticians suggest that when these stars explode, there was no core to collapse into a black hole or neutron star, but the whole star ignites in a thermonuclear reaction spewing its entire self, and newly created elements into the universe. Astronomers are studying a supernova suspect discovered in 2016: SN 2016iet.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

SN 2016iet

The discovery image (right) shows SN 2016iet and its most likely host galaxy. It was taken with the Low Dispersion Survey Spectrograph on the Magellan Clay 6.5-m telescope at Las Campanas Observatory on July 9, 2018. On the left is a pre-discovery image of the area wit a circle of where the supernova would appear.

The article I gleaned this information from:  https://www.skyandtelescope.com/astronomy-news/supernova-that-destroyed-its-star/

It contains a link to the publication preprint.