True Pioneer Robot Headin’ to Taurus
 

       A calling card from Earth is silently heading to the bright, red star in our winter night sky, a true pioneer of mankind’s first steps into interplanetary exploration.

       Pioneer 10 was the first man-made object to pass through the asteroid belt, visit Jupiter and eventually leave the Solar System.

       Launched on March 3, 1972, the TRW-built spacecraft had its switch flipped off on March 31, 1997 when it was about 6 billion miles from Earth.  A few telemetry downloads were squeezed out of Pioneer 10 in 2002 when it was 7.5 billion miles from our Sun, simply a very bright star from that distance.

       Forty-three years after it was sent to the stars, Pioneer 10 is silent as it travels at 27,000 miles per hour in interstellar space.  It is headed toward Aldebaran in Taurus the Bull, the “V-shaped” constellation with the red star that is easy to see in our autumn to early spring night skies.

Today, Pioneer 10 is more than 10 billion miles from the Sun, whose light takes more than 15 hours to reach the spacecraft. Pioneer 10 will take 2 million years to reach Aldebaran, a bloated, red giant of a star, 68 Light Years away.

       But if along the way to Aldebaran aliens snag this strange contraption with the nine foot communications disk, they’ll learn a lot about earthlings.  Welded to the satellite frame is a special plaque that was a bit controversial in the early 1970s for graphically portraying a naked man and woman. 

       The brainchild of astronomer Carl Sagan, this 6x9 inch gold-ionized aluminum plaque was engraved with scientific notation and the image of a man, woman and the Pioneer 10 spacecraft behind them for scale. The outrage of the line drawing showing the man’s penis and woman’s breasts overshadowed the real reason—so aliens know what we look like, where we came from and what our world is made of. 

       The data was ingeniously etched with simple notation in scientific language. There is a chart of our Solar System and Pioneer 10’s left turn at Jupiter and out to interstellar space.

The plaque uses binary code of 0s and 1s for language, the universal hydrogen atom as a yardstick, and the position of 14 “pulsars” in the sky as a bulls-eye to our Sun. The pulsars are the radial lines with their coordinates in binary, the logic being any advanced aliens would know these sites of mega energy output. Pulsars are small neutron stars that emit high energy waves in beams, like a cosmic lighthouse.  

But it was the blatant display of human sex organs that got the ire of some public moral advocates.  Letters to the editors of newspapers who published the Pioneer plaque called it pornographic and obscene.  There was criticism by some religious groups for the lack of a reference to “God” among the clever scientific notation.

Pioneer was a series of NASA satellites that explored the Moon and Venus in the 1960s, each mission a new test for equipment and experiments.  When it was realized that the outer planets would be lined up for a “Grand Tour” by spacecraft in the 1970s, Pioneer 10 to Jupiter and Pioneer 11 to Jupiter and Saturn became the first to push the envelope.  Eventually, Voyager 1 would go to Jupiter and Saturn, and Voyager 2 would complete the “Grand Tour” to Uranus and Neptune in the 1980s.

       The Pioneer 10 was a true pioneer in many ways, including its design.  Because solar panels were no good so far away from the Sun, interplanetary spacecraft need a nuclear source of fuel. And because of radiation effecting scientific instruments, these “RTG” power sources are placed on long booms, away from the main core “bus” of a satellite.

       When launched by an Atlas-Centaur rocket, Pioneer 10 reached a then-high 31,000 mph.  The gravity of Jupiter and its moons changed the velocity of the spacecraft, but nothing in the void of space allows a resistance to the current speed of 26,000 mph. That’s 230 million miles a year.

        Pioneer 10’s sister craft, Pioneer 11, also has an identical etched plaque.  And on the Voyager 1 and 2 spacecrafts of the 1980s, an actual gold record, complete with a needle, were place aboard with images, music and important written words included to explain Earth, humans and our Solar System.

       Voyager 1 actually eclipsed the distance of Pioneer 10, though launched 5 years later in 1977. Voyager 1 is traveling at 10,000 mph faster and has hit 12 billion miles from the Sun—in the minus -200 F. degree void of interstellar space.

       These four stellar voyagers have all left the Solar System and are traveling to the stars. They will soon be joined by NASA’s New Horizon, headed to Pluto in July 2015, then beyond to other “dwarf planets” in the unexplored Kuiper Belt of small bodies circling the Solar System.  Aboard New Horizon are a few messages from its builders, as well as some ashes of 1930 Pluto discoverer Clyde Tombaugh.

 These five American spacecraft are headed to the stars, their design alone a testament to the intelligent creatures that sent them.   

       The message in a bottle that the famous Pioneer and Voyager contain may outlive the Earth itself. Image a civilization actually finding Pioneer 10 and realizing they are the ones who are not alone!  

       Spring Equinox a Welcome Change in Weather

       Spring will finally officially be sprung this Thursday, March 20th as our part of the Earth begins tilting toward our life-sustaining star.

       It’s easy to appreciate the change in seasons, but hard to understand why the weather changes from cold to hot to cold again. In fact, it’s just in the last 400 years that humans have figured out the rhythm of our seasons.

       Seasons happen only because the Earth is a little whacked over on its side.  Instead of spinning like a toy top straight up and down, Earth is tilted 23.5 degrees with a little wobble.  Something whacked us good in the early days of our Solar System, maybe ripping the Moon out of our sides.  And it’s the Moon’s gravity that keeps us tilted the way we are, otherwise, we’d keep wobbling all over the place! We do wobble a little, completing a circle every 26,000 years—and changing North Pole stars in the process.    

       The physics of the seasons is this:  in the Summer our Northern Hemisphere is tilted toward the Sun, and in the Winter we are tilted away.  Sunlight is hotter when striking a surface more direct than at an angle.  Just feel the sun rays on your skin at 10 am, than again at 1 pm.  The higher the Sun angle, the hotter, like around mid-day. 

       That’s what’s happening this week, as Earth reaches a point in its orbit when the angle is between Winter and Summer.  Called the equinoxes, the Spring and Autumn events welcome an equal day and night, with daylight getting longer as the Sun’s arc climbs higher northward. 

       At the Vernal Equinox, the Sun crosses the imaginary line of the ecliptic from the south side to the north, and the Sun is directly overhead at noon. At precisely 12:57 pm DST, the Sun is directly overhead at the Earth's equator. The Sun's daily arch will continue northward, reaching its farthest point north around June 21, the Summer Solstice. The farthest point southward of the Sun's arch against the celestial sphere is the Winter Solstice, around Dec. 21^st.  In between are the Spring and Autumn equinoxes. On Earth, the point where the Sun reaches these points are called the Tropic of Cancer and Tropic of Capricorn—each 23.5 degrees from the equator.

       So, during Winter, our hemisphere is tilted away from the Sun, the indirect rays not being very warm.  But as we move in our orbit and begin to nod toward the Sun, we warm up.  Keep in mind that the Southern Hemisphere experiences just the opposite seasons—so our Vernal Equinox is the first day of Autumn “Down Under” in Australia.

       People find it hard to believe that the Earth is actually farther away from the Sun in the summer, and closer to the Sun in the winter.

       That’s because we live with a Northern Hemisphere bias. The Earth will be farthest from the Sun, called aphelion, on July 3 at 94.5 million miles.  We’re closest to the Sun, perihelion, in the first week of January at around 91.3 million miles. 

Now, a few facts about our Sun, after all, it’s the star of this Vernal Equinox show!

       Just an average star in many ways, our Sun is 865,370 miles across and is basically 99 per cent hydrogen. The Sun is so huge that is contains 99.86 per cent of everything in our Solar System.  Incredibly, all the eight planets, all their moons, tens of thousands of asteroids and millions of comets make up just 0.14 per cent of the mass in our star family!

       So, how hot is the Sun?  The surface temperature is around 10,000 degrees F.  But the center, where nuclear fission splits hydrogen atoms into stellar energy, the temperatures must approach 50 million degrees F. 

       The surface we see of the Sun, the photosphere, is granular like boiling oatmeal.  Electromagnetic storms create the dark and cooler sunspots, and flames of hydrogen lick off the surface, taking three days to reach Earth.  These solar gases are magnetically drawn to the magnetic poles of planets Earth, Jupiter and Saturn and create glowing crowns of aurora.

Sun in Hydrogen Light by Solar Dynamics Observatory

       The Sun rotates once every 33 days with some variances at different latitudes.  Like all stars, it emits many dangerous wavelengths of energy like ultraviolet and x-rays, most are blocked out by our atmosphere.  But some of the UV rays sneak through; toasting gently our skin if exposed too long.

       Nothing travels faster than light, and those sunrays leave the surface of our favorite star at 186,000 miles a second, or about 670 million miles in an hour. Traveling the 93 million miles from the Sun’s surface to Earth takes more than 9 minutes. So when you’re laying on the beach soaking up the Sun, you are looking back in time at our star. 

       Want to see the Sun close up? It is being watched every minute of every day by four powerful space satellites and several major solar observatories on Earth.  Check out the World Wide Web for the McMath-Pierce Solar Telescope at Kitt Peak in Arizona and Big Bear Solar Observatory in California.

In outer space are observatories in a permanent orbit a million miles ahead of the Earth and a million miles behind us at the “Lagrangian Points”. The two unique satellites revealing each side of the Sun are simply called Stereo A and Stereo B. The die-hard sun watcher is the orbiting Solar Heliospheric Observatory (SOHO), which began working in 1996 on a two-year mission that has lasted more than 18 years.

But the real workhorse watching the Sun is the Solar Dynamic Observatory, costing $2 billion and providing the most detailed look at the Sun with its special instruments.  All these great solar observatories have websites devoted to their images, and many are pictures of beauty as well as scientific data. Another great website to daily follow the Sun is Space Weather, which monitors the solar activity in layman’s terms.

       Enjoy our favorite star as it climbs higher in the sky each day, bringing Spring warmth and new vegetative growth to our Northern Hemisphere. And don’t forget to lather up with the sunscreen!

Jupiter is One Crazy Planet

“Now that she’s back in the atmosphere

With drops of Jupiter in her hair,

hey, hey, hey.”   

              Train  “Drops of Jupiter”

No way would any girl want drops of Jupiter in her hair! 

The super-cold hydrogen clouds would freeze her, or the liquid metallic hydrogen surrounding its core mantle would melt her.

But it’s okay to mesmerize her with the sights of Jupiter…just look up at the bright planet Jupiter directly overhead at dark.  The king of the planets is wandering through Gemini Twins, and will be with us through the Spring of 2014.

Jupiter from the Hubble Space Telescope

With any telescope, the giant planet can be seen as a flattened disk with four, star-like moons surrounding it. Two dark bands and grey polar caps are easy to see, and with a serious backyard telescope the detail is amazing.

Jupiter has three times the mass of all the other planets combined—yet it is 1,000 times smaller than the Sun. To put the gigantic size in another way, every planet, moon and asteroid in the Solar System can comfortably fit inside the globe.

There is probably no solid surface to Jupiter.  Most of the 88,800-mile diameter globe is filled with an exotic mixture of – 100 degrees F. cold liquid hydrogen and helium. 

Deep inside the gravity pressure cooker of Jupiter, there may be an Earth-size rocky or liquid core of metallic hydrogen spinning many times a minute.  This creates an electric dynamo, making Jupiter emit more radiation than it receives from the Sun.

One of the many amazing discoveries by NASA’s Galileo spacecraft from 1995-2003 was the intense radiation belts around Jupiter that electrify the surrounding space to a million degrees hot! 

If we could see this electromagnetic system around the “star” Jupiter when looking up tonight, it would be a circle as big as our Full Moon! The NASA spacecraft Juno is headed to Jupiter to study this incredible, high-energy environment.

      The high-altitude hydrogen clouds we see in a telescope are only 5,000 miles thick at the most, just a fraction of the planet’s 44,432-mile radius.

      These cloud tops are an incredibly cold -230 degrees below zero.  And Jupiter has a thin, ropy ring girdling its equator like a hoola-hoop—first discovered by the 1970s Voyager space craft that NASA sent whizzing by. 

      The official moon count is reaching 70 as small, asteroid-like ones are added by advanced research. 

      The Jovian moons we see in a telescope are the same one’s discovered by Galileo in 1610.  Callisto and Ganymede are icy moons larger than the planet Mercury. 

IO, EUROPA, GANYMEDE & CALLISTO

      Two moons, Io and Europa are active worlds in their own right. Both are about the size of Earth’s own Moon.  Io has at least 30 volcanoes spewing sulfuric material into the inner space of Jupiter. Europa is a prime sign for extraterrestrial life in our Solar System.  Europa’s icy surface is fractured with signs of the liquid water heated underneath the alien surface features. Planetary scientists have lobbied NASA for years to provide funds to send a spacecraft to Europa and probe beneath the ice for life.  

The other moons of Jupiter range in size from 1,000 miles to 10 miles in diameter, many with irregular shapes and different compositions.  Some can be seen in serious backyard telescopes. 

Through even the cheapest backyard telescopes, you can watch the four Galilean moons move from side to side of the planet. The moons pass in front of or go behind planet and disappear for a while.  Sometimes all four moons are one side. This Jovian celestial ballet is predictable for centuries in advance.

Though huge in size, Jupiter’s clouds roar around the globe once every 10 hours on the average.  The rotation is so quick it flattens the planet! And inside the clouds are giant cyclones, like the huge Great Red Spot, three times the size of Earth and visible for more than 300 years.  There are intense electrical storms, and incredible aurora at both magnetic poles.   

THE GREAT RED SPOT

Jupiter is located next to the asteroid belt and its immense gravitational influence actually sucks in passing comets and errant asteroids.

That means that Jupiter is taking hits for the inner planets of the Solar System, our Earth included.  Once a rare event to record, amateur astronomers are now recording two or three hits on Jupiter each year with their automated backyard telescopes and digital video cameras.

Just look around the solid bodies of the Solar System and one sees the damage done by violent impacts that mostly occurred in the first quarter of our 4 billion year existence. 

Our Moon alone has more than 100,000 visible impacts, and the planet Mercury is also densely covered with craters.  Natural erosion on Venus and our Earth has wiped away all but the most recent impacts.  On Mars, its less dynamic atmosphere has allowed many crater impacts to still be visible.

      Just like the dramatic impact scars caused by the 1994 comet collision, something struck Jupiter's backside July 19^th causing a supersonic reaction with the atmosphere that created an energy explosion equivalent to dozens of atomic bombs. 

      Yes, if that cosmic debris had impacted Earth, there would be a global catastrophe no matter whether it hit the land or ocean.

      And right at this moment, there are 1,067 Near Earth Asteroids (NEAR) in orbit about the Sun that could smack into us.  They are being monitored by NASA...we hope!  You can check them out at www.spaceweather.com.

      And you can check out all the amazing spacecraft photos and latest news about Jupiter on many websites, including NASA and Jet Propulsion Lab.