The brilliant waxing gibbous moon will erase many stars from the slate of night on July 8, 2014. But the two bright objects flanking tonight’s moon should be able to withstand the moonlit glare. We’re talking about the ringed planet Saturn to the west of the moon and the supergiant red star Antares to the moon’s east. Follow the links below to read more about these two objects.
By the way, look for the moon to be considerably farther east of Saturn – and closer to Antares – on July 9.
Saturn, sixth planet out from the sun, is the farthest world you can easily see with your unaided eye. It’s nearly 10 astronomical units from the sun (10 times the Earth-sun distance), and, right now, it’s about 9.4 astronomical units from Earth. One astronomical unit equals about 150 million kilometers or 93 million miles.
Saturn is often called the jewel of the solar system because of its gorgeous ring system. Saturn’s rings are enormously expansive and wide, but extremely thin. The main rings extend nearly as far the moon’s distance from Earth, yet on the other hand, these rings are only about one kilometer wide. You should be able to see Saturn’s rings fairly easily in July 2014, even with a modest telescope, as they are inclined at 21o from edge-on.
Saturn, the second-largest planet after Jupiter, has a diameter that’s a good 9 times greater than Earth’s. Like Jupiter, Saturn is a gas giant world, composed of mainly hydrogen and helium. Unlike the inner rocky planets – Mercury, Venus, Earth and Mars – Saturn and Jupiter have no solid surfaces on which to stand.
Antares is the brightest star in the constellation Scorpius the Scorpion. It is a red supergiant star. In fact, this star dwarfs the sun to almost nothingness. While the volume of the sun is approximately 1.3 million times that of our planet Earth, Antares has the volume of hundreds of millions of suns. If by some bit of magic Antares was suddenly substituted for our sun, the surface of the star would extend well past the orbit of Mars!
Antares is classified as an M1 supergiant star. The M1 designation says that Antares is reddish in color and cooler than many other stars. Its surface temperature of 3500 kelvins (about 5800 degrees F.) is in contrast to about 10,000 degrees F. for our sun.
Even though Antares’ surface temperature is relatively low, Antares’ tremendous surface area – the surface from which light can escape – makes this star very bright. In fact, Antares approaches 11,000 times the brilliance of our puny sun, a G2 star.
But that is just in visible light. When all wavelengths of electromagnetic radiation is considered, Antares pumps out more than 60,000 times the energy of our sun!
Bottom line: Look at the moon on July 8, 2014, and you will notice two objects on either side of it. One is the planet Saturn, and the other is the star Antares. Saturn is the jewel of our solar system, and Antares is a giant among stars. Read about them here.