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: Manchester scientists boost NASA's missions to Mars

add to favorites email to friend print save as pdf

Related Stories

Mars, too, has macroweather

Nov 13, 2014

Weather, which changes day-to-day due to constant fluctuations in the atmosphere, and climate, which varies over decades, are familiar. More recently, a third regime, called "macroweather," has been used ...

A close-up with a comet

Nov 11, 2014

Even as Tom Economou approached retirement age in 1994, he began planning an instrument for the European Space Agency's Rosetta mission to a comet. He still remembers the reaction of Riccardo Levi-Setti, ...

Life can survive on much less water than you might think

Nov 04, 2014

"Follow the water" has long been the mantra of our scientific search for alien life in the Solar System and beyond. We continue seeking conditions where water can remain liquid either on a world's surface ...

The formation and development of desert dunes on Titan

Oct 23, 2014

Combining climate models and observations of the surface of Titan from the Cassini probe, a team from the AIM Astrophysics Laboratory (CNRS / CEA / Paris Diderot University) , in collaboration with researchers ...

Recommended for you

Bad weather delays Japan asteroid probe lift off

3 hours ago

Bad weather will delay the launch of a Japanese space probe on a six-year mission to mine a distant asteroid, just weeks after a European spacecraft's historic landing on a comet captivated the world.

Manchester scientists boost NASA's missions to Mars

11 hours ago

Computer Scientists from The University of Manchester have boosted NASA space missions by pioneering a global project to develop programs that efficiently test and control NASA spacecraft.

ESA image: The gold standard

12 hours ago

The Eutelsat-9B satellite with its EDRS-A payload is shown in the anechoic test chamber of Airbus Defence and Space in Toulouse, France, having completed its final antenna pattern tests today.

Frost-covered chaos on Mars

12 hours ago

Thanks to a break in the dusty 'weather' over the giant Hellas Basin at the beginning of this year, ESA's Mars Express was able to look down into the seven kilometre-deep basin and onto the frosty surface ...

Rosetta's comet: In the shadow of the coma

19 hours ago

This NAVCAM mosaic comprises four individual images taken on 20 November from a distance of 30.8 km from the centre of Comet 67P/C-G. The image resolution is 2.6 m/pixel, so each original 1024 x 1024 pixel ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.