The evening sky is free of the moon for several days, making it a good time to look for one of the largest but faintest constellations, Eridanus the River.
A good portion of Eridanus is readily visible from Tucson. If you are south of Tucson away from city lights and have a very clear southern horizon, you have a much better chance of seeing the full extent of the constellation. Eridanus is a meandering string of fairly faint stars that starts near the bright star Rigel at the western foot of Orion the Hunter and ends 60 degrees west of Orion at Achernar, the ninth-brightest star in the sky.
Look for Eridanus around 7 p.m. Orion is in the southeast, and Eridanus stretches across the southeastern sky with Achernar directly south just above the horizon. Eridanus is fairly dim and not spectacular, but it at least resembles what it is supposed to represent. Achernar is always a challenge as it is so far south. I have seen it hovering above the horizon several times from Sonoita.
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It is even more amazing when you consider Achernar is 144 light years away and at least 2,900 times more luminous than the sun. Achernar is six to eight times more massive than the sun and is an elongated, egg-shaped object with a very fast rotation period of only 2.2 days, a strange star indeed.
