SKY_July2014.pdf

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Star

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Gary Seronik

Binocular Highlight

SkyandTelescope.com July 2014 45

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Ceres

Vesta

VIRGO

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Ceres and Vesta Together

Most objects we view in binoculars lie far beyond

the solar system — and sometimes outside our

Milky Way Galaxy. Clusters, nebulae, and galaxies

are all rewarding in their own ways, but their appeal

is largely static. They’re attractive but unchang-

ing. Once in a while it’s nice to see the celestial

machinery in action. Luckily, the asteroids Ceres

and Vesta are putting on a fi ne demonstration

right now.

Asteroids appear as mere points of light, but

it’s fascinating to watch them move night by night

against the background stars — and in this case,

relative to each other. Of the two, Vesta is brighter,

shining at magnitude 7.1 at the beginning of July

versus 8.4 for Ceres. That means that both objects

are binocular targets, even under suburban skies.

But they’re in Virgo, which is sinking low in the

west, so make sure you look for them as soon as

the sky grows fully dark.

The asteroids have been within the same

binocular fi eld for months. But on the American

evenings of July 4th (shown below) and 5th, they

will be at their very closest — just 10′ apart. That’s

still a large enough gap that steadily held binos

will be able to show both objects as distinct dots.

The pair is situated near a handy reference point,

3.4-magnitude Zeta (ζ) Virginis. The star lies in the

same binocular fi eld as Ceres and Vesta and makes

tracking their changing positions much easier. If

you’re clouded out on July 4th, the chart on page 50

shows where to fi nd them later in the month.

Don’t pass up this rare chance to see the wheels

of the celestial machinery in motion! ✦

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Saturn

Moon

July 8

MoonJuly 4

Mars

When

Late May 2 a.m.*

Early June 1 a.m.*

Late June Midnight*

Early July 11 p.m.*

Late July Nightfall

*Daylight-saving time.