Bob Moler's Ephemeris Blog

Ephemeris for Tuesday, August 21st. The Sun rises at 6:52. It’ll be up for 13 hours and 46 minutes, setting at 8:38. The Moon, 3 days past first quarter, will set at 3:09 tomorrow morning.

I introduced the Parker Solar Probe yesterday. It’s on its way to Venus to have some of its velocity stolen by that planet as to drop to nearly 15 million miles (24 million km) of the Sun at its first perihelion, before heading almost all the way out to the Earth’s orbit. Its next encounter with Venus will steal even more velocity from the probe to drop even closer to the Sun. It will take nearly 7 years to reach as close as 3.9 million miles (6.2 million km) from he center of the Sun of 3.8 million miles (6.1 million km) from what looks like its surface, the photosphere, the bright ball we see of the Sun. The probe has a huge heat shield that will handle the over two thousand degree heat from the Sun. Even though the corona is several million degrees in temperature, it’s not dense enough to heat the probe.

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

Addendum

The planned orbits of the Parker Solar Probe. First flyby of Venus will occur on October 3rd 2018. The first perihelion passage a bit more than a month later on November 6th. Credit: NASA

A close look at the Sun

Click on image to enlarge. Credit NASA.