Where When How — Summer 2017
Change Language:
Skywatch - The Night Sky
Dr. Thomas Lesser



Meteors or “shooting stars” are flashes of light that happen so quickly that by the time you tell a friend “look there”, the meteor will be gone. Meteors are caused by pebble sized bits of rock burning up as they pass through the air some 50 miles above the Earth. On any clear night you can see several shooting stars or meteors per hour. At the time of a meteor shower you can see many many more. As the comet passes through space, it gives off gas and bits of dust. When the earth passes through a cloud of this comet dust we have a meteor shower. Historically there have been a few meteor showers that produced 10,000 or even 100,000 shooting stars per hour. But, those events are very unusual.

The Delta Aquarids is an average shower that can produce up to 20 meteors per hour at its peak on the night of July 29th to the morning of July 30th.

In the early morning hours of August 12th you will be able to see the Perseid meteor shower, the best meteor shower of the year. The comet which left the dust behind that forms the Perseids is comet Swift-Tuttle. Swift-Tuttle was discovered in 1862. It was found again in 1992 and astronomers have since found records of it going back to 69 BC.

The Orionids is an average shower producing up to 20 meteors per hour at its peak. It is produced by dust grains left behind by comet Halley, which has been known and observed since ancient times. The shower peaks this year on the morning of October 22nd.

On August 21st the Moon will come directly between the Earth and the Sun and there will be a solar eclipse. From the northern Pacific Ocean, across much of the United States, and out into the Atlantic Ocean the Moon will completely block out the Sun and people will experience a Total Solar Eclipse. In Turks and Caicos the Moon will only partially cover the Sun: the partial eclipse begins at 1:54 pm, the maximum of the eclipse is at 3:21 pm, and the partial eclipse ends at 4:37 pm. It is important to never look directly at the Sun without proper eye protection. Sunglasses are NOT proper eye protection.

On September 22nd the Sun will shine directly overhead on the equator and there will be nearly equal amounts of day and night throughout the world. This is also the first day of Fall (autumnal equinox) in the Northern Hemisphere and the first day of Spring (vernal equinox) in the Southern Hemisphere.

In the evening two bright planets by two bright stars make interesting sky watching. High in the west is the very bright star-like object Jupiter. Just south of Jupiter is the bright star of Spica, a grain of wheat being held in the hand of Virgo, the goddess of the harvest. High in the southern sky is a bright red star, Antares, the red heart of Scorpius, the scorpion. North of July: Sunrise 6:11 / Sunset 7:30 - August: Sunrise 6:23 / Sunset 7:14 Sept: Sunrise 6:42/ Sunset 6:37 - Oct: Sunrise 6:41 / Sunset 6:20 Antares is a bright star-like object, not as bright as Jupiter, this is Saturn. Antares is the heart of the scorpion, perhaps you can see the stars that form the scorpion’s long curved tail. Scorpius is one of the few constellations, or star groups, that looks something like you think it should.

The early morning eastern sky will be dominated by Venus, the third brightest natural object in the sky after the Sun and the Moon.

Returning to the evening sky, look for three bright stars which form a large triangle. Since the triangle is visible all night long during the Summer up north, it is called the Summer Triangle. Each bright star marks a different star group or constellation. Farthest West and lowest in the sky is Vega, part of Lyra the Harp. To the South is Altair, in Aquila the Eagle. The third bright star is Deneb, marking the tail of Cygnus, the Swan. Perhaps you can see other stars that form the Swan’s body, neck and head and its wings which spread wide. Cygnus is flying South along the Milky Way. The Milky Way looks like a hazy band of light arcing across the sky. It is the light from billions and billions of stars so far away, that all we see is their light combined into this haze.

This column is prepared especially for TCI stargazers by DR. THOMAS LESSER