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09/30/2022 – Ephemeris – View the Sun and Moon tomorrow in the Grand Traverse Area!

September 30, 2022 Comments off

This is Ephemeris for Friday, September 30th. Today the Sun will be up for 11 hours and 45 minutes, setting at 7:25, and it will rise tomorrow at 7:40. The Moon, 2 days before first quarter, will set at 9:57 this evening.

There are two observing sessions tomorrow in the Traverse City area with the assistance of the Grand Traverse Astronomical Society. First at the Dennos Museum Center grounds, from 2 to 4 pm, there will be telescopes to safely view the Sun. The Sun’s eleven-year sunspot cycle is getting active again. There will be telescopes to see those sunspots, and special solar hydrogen alpha telescopes to view the Sun’s chromosphere and any prominences above the Sun that day. From 8 to 10 pm, Northwestern Michigan College’s Rogers Observatory will be open for International Observe The Moon Night. There will also be a telescope on the 200 Block of East Front Street to observe the Moon during this time. Of course, all this is contingent on clear or mostly clear skies.

Update: It’s supposed to be nice this weekend, after a week of cold and rain.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Later today I’ll add a Moon Map for tomorrow evening and what the Sun looks like today, which should give a clue to what’s happening on the Sun now.

Sun in white light (How we normally see it with a solar filter)

Sun in white light

The Sun in white light, by the Solar Dynamics Observatory on September 30, 2022. What is seen is the photosphere, the visible “surface” of the Sun, where the energy transport from the interior changes from convection to radiation. The apparent roughness of the surface are the tops of the convection cells, called granules, which are usually about 600 miles wide that bubble up and recede. The numbers label active areas. The dark spots are sunspots, areas of intense magnetic activity. Brighter wispy or splotchy areas are faculae and are associated with sunspots or precursors of a new group forming.  The rotation of the Sun will move the surface features from left to right in this image with north up. Telescopes may show the image upside down or mirror reversed. Click on the image to enlarge it. Credit NASA/SDO.

Sun in the light of the Hydrogen Alpha wavelength. Light absorbed and emitted by the hydrogen atom.

The Sun in Hydrogen-Alpha light

The Sun in Hydrogen-Alpha light, taken at 10:19 EDT today, September 30, 2022. It is in the same orientation as the SDO image above, but may have been taken at a different time of the day. This image was taken from the web page https://gong2.nso.edu/products/tableView/table.php?configFile=configs/hAlpha.cfg I colorized the image to show how it would look in a Hydrogen-Alpha telescope, of which we may have several, both the society’s and personal. The images may be dim since they select one narrow frequency of light from the broad spectrum of white light coming up from the photosphere. Its temperature is 10,000 degrees F. The thin dark markings are called filaments. These are the same thing as the bright prominences seen off the edge or limb of the Sun. Brighter areas of the chromosphere are called plages and are associated with active regions. The Chromosphere is a thin layer of the Sun’s atmosphere lying above the photosphere only 3,000 miles thick, and slightly hotter than the photosphere, its appearance is rougher than the granules of the photosphere. It reminds me of uneven, red grass that hasn’t been mown in a few weeks. They grow and recede in minutes. Sometimes a bright spot will appear in a sunspot group. These are solar flares and are caused by magnetic disruptions in sunspot groups. They last only a relatively few minutes but emit x-rays, electrons and protons as the most energetic explosions in the solar system. The x-rays arrive at Earth in 8 and a half minutes at the speed of light, the particles a day or two later will affect the Earth’s magnetic field if aimed in our direction, causing the aurora (northern and southern lights), and possibly disrupt communications and the power grid. On Earth, it’s called a geomagnetic storm.

The Moon for Saturday evening during the International Observe the Moon Night

The Moon as it should appear at 9 pm EDT, October 1st, 2022

The Moon as it should appear at 9 pm EDT, October 1st, 2022. The telescopic image would be sharper than this. Created using Virtual Moon Atlas.

Download page of maps from the Official 2022 International Observe the Moon Night website.

Images in astronomical telescopes produce images of various orientations. They may be right side up or upside down, mirror reversed or both. Telescopes with an odd number of mirrors produce mirror images. Astronomers are used to it, though they have a preferred orientation… The one their favorable telescope produces.

Come on out!