Spot Vesta with naked eyes

There is a rare treat for the sky observers. With the unaided eye, you will be able to view an asteroid called Vesta. Vesta is the only asteroid that we can ever see with the naked eye. There are countless asteroids in our Solar System, around 50,000 have names or identifying numbers. But of all of them, only Vesta ever becomes close and bright enough for us to spot with the unaided eye.

Vesta was discovered March 29, 1807 by the German physician Heinrich Olbers. Olbers thought he had found a new star but soon realized he had found an asteroid. Vesta is one of the brightest Main Belt asteroids and slightly over 540km in diameter but it is slightly elongated in shape. It is the second largest asteroid discovered to date. Vesta is unique among the asteroids studied so far because it appears to have differentiated into layers like the planets. Differentiation is the separation of material according to density. This seems to imply some internal heat source.

Vesta is so bright because it has a very high surface reflectivity, called as albedo in scientific terms. Ceres (largest known asteroid) reflects only about 11 percent of the sunlight striking it, but Vesta reflects a whopping 42 percent! And that is why the unaided eye can see Vesta but not Ceres.

Use the sky map to aid spotting the asteroid. Keep in mind that Vesta is not a bright object and you will need dark skies, away from artificial lights, to see it. It's a very difficult task to locate it and you will need an exact position as it will appear as only faint star to you.