The distinctive shape of Bootes is often compared to an ice cream cone or a tie, and it is easy to recognize. The constellation is far away from the Milky Way, but it contains no brighter deep-sky objects.

The 0.16m bright α Bootis (Arcturus) is the fourth brightest star in the sky and only 36.7 light-years away from our Sun. Although its diameter is 27 times that of the Sun, it has only four solar masses. Arcturus is an old star from the halo of the Milky Way, which currently crosses the galactic plane at 73 miles per second (118 km/s) diagonally to the direction of our Sun. Two million years ago it was about 800 light-years away, and in another two million years it will be visible only as a 6.7m bright star in the constellation of Vela, the Sails. Meanwhile it comes even closer to the Earth every second by three miles (five kilometers).

ι Bootis shines high in the northwest of the constellation, close to the border of Ursa Major. Under good conditions, sevenfold magnification is sufficient to detect a 7.4m companion in 39 arc seconds distance to the 4.8m bright main star. The brighter star is nine times more luminous than our Sun and 97.2 light-years away, the companion is only half as bright as the Sun and 71 light-years away. The optical double star shows a slight color contrast.

µ Bootis is also named Alkalurops (the “Walking Stick“) and is a physical double star at a distance of 121 light-years. To the naked eye it appears as a bright star of 4.3m, forming a flat triangle with β and δ. In binoculars you can easily distinguish a 6.5m bright companion 108 arc seconds away, which corresponds to 3,000 AU from the primary star – 1 AU is the distance between the Sun and Earth, at about 93.2 million miles (150 million kilometers). It is quite similar to our Sun and encircled every 260 years by another, similarly sized star only 43 AU away, but this third star can only be separated in a telescope.

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