Planets Align for the 4th of July

Jul 02, 2008
Planets Align for the 4th of July
Fireworks over Jodrell Bank, England, on the 2008 summer solstice. Photo credit: Andrew Greenwood.

News Flash: On 4th of July weekend, NASA forecasts lights in the sky. No, not those lights. Look beyond the fireworks. Almost halfway up the western sky, just above the twilight glow of sunset, a trio of worlds is gathering: Saturn, Mars and the crescent Moon.

The show gets going on Friday, July 4th. Red Mars and ringed Saturn converge just to the left of the bright star Regulus. The three lights make a pretty 1st-magnitude line in the heavens: sky map.

But that is just the beginning. On Saturday, July 5th, with weekend fireworks at fever pitch, a lovely crescent Moon joins the show. Saturn, Mars, and the Moon trace an even brighter line than the night before: sky map.

Scan a small telescope along the line. You'll see Saturn's rings, the little red disk of Mars, a grand sweep of lunar mountains and craters, and just maybe—flash!—a manmade incendiary. How often do you see fireworks through a telescope?

This is, however, more than just a flashy gathering of planets—it is also a gathering of spaceships and robots.

Each of the three worlds is orbited or inhabited by probes from Earth. Saturn has the Cassini spacecraft, studying the gas giant's storms, moons and rings. The Moon has two probes in orbit: Kaguya from Japan and Chang'e-1 from China. The pair, operating independently, are mapping the Moon and scanning for resources in advance of future human landings. NASA's Lunar Reconnaissance Orbiter will join them later this year.

Mars has more probes than the others combined. Three active satellites orbit the red planet: Europe's Mars Express and NASA's Mars Odyssey and Mars Reconnaissance Orbiter. The three not only study Mars with their own instruments, but also form a satellite network in support of NASA's Mars rovers Spirit and Opportunity and Mars lander Phoenix.

None of these mechanical specks are visible in a backyard telescope, but they are there, heralds of a growing human presence in the solar system. Tell that to your buddy at the fireworks show!

During the short night of July 5th, the Moon glides past Mars and Saturn so that nightfall on Sunday, July 6th, brings a different arrangement—a scalene triangle. The triad is easy to find in the hours after sunset. Look west and let the Moon be your guide: sky map.

In the nights that follow, the Moon exits stage left, leaving the others behind. Don't stop watching, though. Saturn and Mars are converging for their closest encounter of the next 14 years. After nightfall on Thursday, July 10th, the two planets will be just ¾ of a degree apart, snug enough to fit behind the tip of your pinky finger held at arm's length: sky map.

Now that's spectacular—no fireworks required.

Source: Science@NASA, Dr. Tony Phillips

Explore further: Full lunar eclipse delights Americas, first of year

add to favorites email to friend print save as pdf

Related Stories

Curiosity's first photo of home planet Earth from Mars

Feb 07, 2014

18 months into her mission to discover a habitable zone on the Red Planet, NASA's Curiosity rover has at last looked back to the inhabited zone of all humanity and snapped her 1st image of all 7 Billion Earthlings ...

In the eye of the beholder

Jan 24, 2014

Astrobiologists are developing 'intelligent' instruments that could help future robotic explorers make their own decisions about where and how to collect data. Although focused on Mars exploration for the ...

Recommended for you

Vegetables on Mars within ten years?

16 hours ago

The soil on Mars may be suitable for cultivating food crops – this is the prognosis of a study by plant ecologist Wieger Wamelink of Wageningen UR. This would prove highly practical if we ever decide to ...

NASA Cassini images may reveal birth of a Saturn moon

17 hours ago

(Phys.org) —NASA's Cassini spacecraft has documented the formation of a small icy object within the rings of Saturn that may be a new moon, and may also provide clues to the formation of the planet's known ...

Meteorite studies suggest hidden water on Mars

17 hours ago

Geochemical calculations by researchers at Tokyo Institute of Technology to determine how the water content of Mars has changed over the past 4.5 billion years suggest as yet unidentified reservoirs of water ...

User comments : 0

More news stories

Astronomers: 'Tilt-a-worlds' could harbor life

A fluctuating tilt in a planet's orbit does not preclude the possibility of life, according to new research by astronomers at the University of Washington, Utah's Weber State University and NASA. In fact, ...

NASA Cassini images may reveal birth of a Saturn moon

(Phys.org) —NASA's Cassini spacecraft has documented the formation of a small icy object within the rings of Saturn that may be a new moon, and may also provide clues to the formation of the planet's known ...

Vegetables on Mars within ten years?

The soil on Mars may be suitable for cultivating food crops – this is the prognosis of a study by plant ecologist Wieger Wamelink of Wageningen UR. This would prove highly practical if we ever decide to ...

Low Vitamin D may not be a culprit in menopause symptoms

A new study from the Women's Health Initiative (WHI) shows no significant connection between vitamin D levels and menopause symptoms. The study was published online today in Menopause, the journal of The North American Menopa ...