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What is the nearest huge cluster of thousands of galaxies, to which the Local Group may belong?

According to Hubble’s Law, the greater a galaxy’s redshift, the

In what sense are the quasars “quasi-stellar”?

Change the date to July 5, 2009. What is the approximate angular separation between the star Antares and the Moon on this date?

Change the time flow rate to 1 day (solar day). Note the position of the Moon and the background stars and click the Step Time Forward button to advance time by 1 solar day. Then change the time flow rate to 1 sidereal d. (sidereal day) and watch the Moon and stars in the view when you click the Step Time Forward button again, this time to advance time by 1 sidereal day. Repeat these steps to decide which of the following statements is NOT correct.

Place the adaptive hand cursor over the star Antares. How far away from you (the observer) is Antares?

The Galactic Year is the time for our solar system to orbit the Galaxy; it is about

The core of the Milky Way, Sagittarius A, is a strong radio source in the sky.

Right-click (Ctrl-click on a Macintosh) over the Moon in the view and select Magnify from the contextual menu that appears. Then use the Zoom buttons in the toolbar to magnify the Moon until it fills the entire main window. Read the zoom display. Roughly, what is the angular diameter of the Moon?

William Herschel’s original model for our Galaxy was based on counting stars.