Advertisement

Summer’s Special Attractions : Planets, constellations and the dazzling Perseid meteor shower are all out there for the gazing.

Share via
Special to The Times; <i> Jeff Schnaufer is a regular contributor to The Times. </i>

Blazing meteors, shimmering star clusters, mysterious craters and planets that dangle in the sky like jewels. For the beginning stargazer, August presents a perfect opportunity to get stars in your eyes. Some professional astronomers even say you could not have picked a better month, as this is a time when the Perseid meteor shower could make cosmic history.

“This may be the best Perseid meteor shower ever,” says Tony Cook, astronomical observer at Griffith Observatory and a North Hollywood resident. “This year, it’s particularly interesting because, on the night of Aug. 11, the Earth is expected to pass directly through the orbit of Comet Swift-Tuttle.”

The orbit is littered with tiny particles of dust from the comet, in this case a fragmented string of “dirty icebergs” hurtling through the solar system. Like a car windshield passing through a swarm of locusts, Earth’s atmosphere will collide with the cosmic dust. These particles will ignite and create the misnamed “shooting star” effect as they burn their way toward the ground. They strike the atmosphere at nearly 130,000 m.p.h.

Advertisement

Cook says there could be as many as hundreds of meteors per hour. Because of Earth’s orientation, the best viewing for this shower will be in Europe. Even so, Cook says Southern California residents may still be treated to a spectacular show. The best time to look for meteors will about 1 a.m. Aug. 12, but you can begin your search the evening of Aug. 11.

Sheer luck, more than anything, is often the key to meteor watching. For this reason, astronomers suggest taking a group of friends out to see the Perseids. By pooling your vision, you keep watch over more of the sky.

The darker the sky, the more meteors you will see. Take something to lie on, and look toward the northeast. The naked eye is the astronomer’s preferred tool.

Advertisement

While looking for the Perseids, use your naked eye to seek out this month’s best celestial wonders. The “Night Sky in August” star chart (Page 11) will help you find them. Then read the following background to find stellar treats for the naked eye, binoculars and telescopes:

THE STARS: On a clear, dark evening away from city lights, more than 2,000 stars are visible to the naked eye. Each pinpoint of light is a distant star many light-years (the distance light travels in one year, about 6 trillion miles) away. Some, such as Vega in the constellation Lyre, are young, hot stars similar to our sun in its early years, frantically fusing hydrogen into helium to create energy. Others, such as Antares, the heart of Scorpius the scorpion, are older red giants more than 700 times the diameter of our sun. Depending on their original mass and whether they had a binary companion, dying stars that empty their hydrogen can create explosive flashes called novas and supernovae that can be seen from the Earth, sometimes with the naked eye.

BIG AND LITTLE DIPPER (Big and Little Bear / Ursa Major and Ursa Minor): According to the Greeks, these constellations were formed by a love spat. Callisto was a beautiful girl with whom Jupiter fell in love. Juno, Jupiter’s wife, became jealous and changed Callisto into a bear. One day, Callisto saw her son Arcas and rushed toward him. Arcas raised his spear to kill the charging bear, unaware that it was his mother. Jupiter saved Callisto by turning Arcas into a bear as well, then pulled the bears into the sky by their tails, which explains why the tails are so long.

Advertisement

The tip of the Little Bear’s (Arcas’) tail is actually the North Star, or Polaris. Almost directly above our planet’s north celestial pole, Polaris stays steady as the other stars seem to move through the night. Of course, it is the Earth that rotates, causing this effect.

Today, many stargazers refer to the two bears as the Big Dipper and Little Dipper.

Some ancient cultures reputedly used two of the stars in the Big Dipper as a vision test. The middle star in the handle of the Dipper is actually two stars, bright Mizar and more faint Alcor, so close together that they almost appear to be one star. Try separating them with your eyes, then take a look at the pair with a small telescope. You will see that Mizar is two stars, Mizar A and Mizar B. In fact, Mizar A and Mizar B are actually each two star systems themselves. Unlike our sun, most of the stars in our Milky Way galaxy are double stars.

The most intriguing tale of the Big Bear comes from the Iroquois Indians. In the spring, the bear left his den (Corona Borealis), chased by seven hunters, three of which are the brightest stars in the handle of the Big Dipper. Alcor is a pot carried by hunter Mizar to cook the bear in. Only these three hunters remain visible by fall, when one of them strikes the bear with an arrow, trickling his blood to the ground and onto one of the hunters, named Robin. That is why, the Iroquois said, leaves turn red in fall and the robin has a red breast.

CASSIOPEIA AND ANDROMEDA: Named after a queen in Greek mythology, the constellation Cassiopeia better resembles a letter W or M. Halfway between it and the constellation Andromeda is an undisputed sight, our closest cosmic cross-town rival, the Andromeda galaxy, 2.1 million light-years away. Visible even with the naked eye as a nebulous speck of light, this spiral galaxy contains as many as 400 billion stars and is best seen through binoculars or a small telescope.

HERCULES: This is a popular constellation for testing star-hopping skills. Train your binoculars or telescope on his right hip, where you will find a circular, fuzzy patch of light. This is the Hercules globular cluster. Containing 100,000 to 1 million older stars, this cluster was the target of the first purposeful radio message from Earth in search of alien intelligence, sent in 1974. With any luck, we should get an answer by the year 51,974.

JUPITER: The bright light low in the southwest at sunset is the planet Jupiter, the largest planet in the solar system. If Earth were a dime, Jupiter would be a dinner plate. A small telescope will reveal Jupiter’s great red spot (a cyclonic storm bigger than three Earths) and four of its 16 known moons: Ganymede, Europa, Callisto and Io, which change position daily. A massive ball of hydrogen and helium gas, Jupiter is best viewed early this month.

Advertisement

MOON: Even with the naked eye 239,000 miles away, an observer on Earth can see the ancient lava flows of the moon, dark lunar “seas” known as maria, formed 3 billion to 4 billion years ago. During a young, crescent-phase moon, the Earth’s reflection of sunlight faintly illuminates the “dark” part of the moon, a phenomenon called “earthshine,” even more spectacular when viewed with binoculars. Observing with a telescope before a first-quarter moon, you can see many shadows in the moon’s estimated 500,000 Earth-facing craters, as well as breathtaking views of the lunar mountains, some 18,000 feet high.

SAGITTARIUS AND THE MILKY WAY: Although the Greeks recognized the constellation Sagittarius as an archer, a more modern description is that of a teapot, with the Milky Way being the “steam” rising out of its spout. To the Algonquin Indians, the Milky Way was a trail that souls follow into heaven, each star a campfire blazing in the sky where they have paused in their journey. Today, astronomers know this “trail” as the inside view of our galaxy, containing as many as 400 billion stars. Toward Sagittarius is the center of our galaxy, 30,000 light-years away, where some scientists believe lies a super-massive black hole.

SATURN: The jewel of the solar system, Saturn can be seen rising in the southeast near sunset. With a small telescope, observers can see the planet’s rings, which stretch about 171,000 miles in diameter, but less than a mile thick. The rings are composed of icy particles ranging in size from a grain of sand to a school bus.

SUMMER TRIANGLE: This is actually three constellations in one, marked by three bright stars, Vega (in Lyra, the lyre), Deneb (in Cygnus, the swan) and Altair (in Aquila, the eagle). Cygnus is also referred to as the Northern Cross. With binoculars, the swan’s “eye,” Albireo, appears as a brilliant double star, gold and blue.

Advertisement