May 2003

• Upcoming Explorations
  
  
• Planetary Update
  
  
• Constellation of the Month
  
  
• The Moon
  

Upcoming Explorations

This is an exciting time for space exploration! Some spacecraft are already on their way, with plenty more about to be launched. We will have unprecedented views of Mars, Jupiter, Saturn, Pluto, and beyond!! Below are a couple projects I think are of interest -- some already on their intrepid journeys, and a couple coming up soon.

The first of the United States' contribution to the FIVE missions to land on Mars will be launched on June 6th, 2003 (as of this writing, that is only 32 days away!).

The U.S. is launching two Mars Exploration Rovers in June. The European Space Agency will be sending a lander called Beagle, and an orbiter called Mars Express. Japan is sending an orbiter called Nozomi (that one has been on its way for a while...).

Why is Mars such a popular target? At the end of August, Mars will be closer to the Earth than it has been for a little over 60,000 years! This is the moment for humanity to blast off to Mars. We still do not have the technology to successfully send humans to Mars, and safely bring them back. A trip to the Moon and back is an extremely difficult endeavor, and that takes little more than a week to get there and back. A ONE-WAY trip to Mars is about 7 MONTHS.

The Mars Exploration Rovers, to be launched next month will provide us an incredible wealth of information about the surface and geological history of Mars.

The Rovers will have a stereoscopic ultra-high resolution camera, taking the highest quality 3-D pictures of the surface of Mars we have ever seen! There will also be a thermal spectrometer camera on board, which will be able to detect organic molecules, as well as many other types. It can help us to determine whether life ever existed on Mars, and, if so, the best places to look for it. There is also an X-Ray camera on board, which will take a variety of readings which will complement the readings taken by the thermal spectrometer.

Since Mars is so iron-rich, taken readings using a magnet is quite useful. There is a magnetic spectrometer on board, as well, which will use the iron content to help us determine the composition of many of the rocks. As we study the rocks, there is also a tiny drill/grinder on board which can cut a shallow hole in a rock, and, using a microscope camera, be able to take pictures of the inside of the rocks. We will be able to analyze the geological history of Mars, and perhaps find evidence of a fossil record!

More information on the mission and the equipment on board...

Galileo to Impact Jupiter.

The Galileo spacecraft has been a sturdy traveler, with unprecedented longevity! Launched in October, 1989, the primary mission was supposed to last until December, 1997. It was to launch a probe into Jupiter's atmosphere, and study the giant planet and some of its moons.

The only real problem Galileo faced was that its large antenna did not deploy. It was folded up like an umbrella, and upon arrival at Jupiter, it was stuck closed -- a position it remains in today. There is a smaller antenna, which is sufficient to send information back to Earth, and that has been the source of data we have received from the intrepid traveler.

In 1997, with plenty of fuel, and equipment still operational, NASA decided to extend the Galileo mission. The Galileo mission has provided a wealth of information about Jupiter, but also got some tremendous pictures and information about some asteroids on the way. It has also given us evidence of subsurface liquid water on three of Jupiter's largest moons (Europa, Callisto, and Ganymede). The extended mission has given us more information about the fine rings of Jupiter, so thin that they are invisible from Earth, and got a look at a small moon, Amalthea -- one of the closest to Jupiter. (By the way, recent observations of Jupiter continue to reveal new moons. The count of Jupiter's moons now stands at 60!)

Galileo's fuel is running low. We will not be able to continue to control the trajectory of it and to point its antenna in useful directions. There are concerns about Galileo making an impact on one of the giant moons of Jupiter. Europa, the moon which appears to have the most plentiful amount of liquid water, has raised concerns among scientists. If there is a bunch of water on Europa, could there be life? If so, would an impact disrupt the life there? In order to avoid this possibility, the final trajectory change to Galileo put it on an unalterable collision course with Jupiter.

The Galileo mission will end when the spacecraft impacts Jupiter on September 21, 2003.

Learn more about the mission!

Cassini to Saturn.

There's a mission currently underway on its way to the next planet out -- Saturn!

The rocket carrying Cassini was launched back in October of 1997; it will reach its destination in the beginning of July of next year.

Saturn has always been a mysterious object to view, it having the only planetary rings visible with a backyard telescope. That telescope should also be able to spot Saturn's largest moon: Titan. The body of Saturn, its rings, and Titan make up the majority of the Cassini mission.

The main component of the spacecraft, the Cassini orbiter, has an extensive array of cameras and equipment. It will be studying the magnetic fields of Saturn, as well as the turbulent atmosphere (we've seen evidence that wind near the equator of Saturn has exceeded 1000 miles per hour!). It will study the composition of Saturn, and be able to 'see' charged gas particles, radio waves, and the composition of dust particles around Saturn using special cameras that record wavelengths of light outside of the range of human eyes.

Cassini carries a probe, built by the European Space Agency, called Huygens. It is named after Christian Huygens, the astronomer who discovered Saturn's largest moon Titan. It is aptly named, since the Huygens probe will detach from Cassini in December of 2004, and head towards Titan. After a three-week cruise to the giant moon (it is truly a giant moon; bigger than two of the planets: Mercury and Pluto!), it will descend to the surface, using a collection of parachutes to slow its descent. In January 2005, it will hold the record of landing on the furthest object from Earth!

Titan has been of great interest to space scientists since the Voyager spacecraft took readings of its thick atmosphere back in the 1980's. It has an atmosphere thicker than Earth's, consisting mainly of Nitrogen and Methane, and it is a close approximation of what scientists believe the early Earth atmosphere was like, billions of years ago. Studying Titan is like studying an ancient living fossil of the Earth!

Next year will certainly bring us exciting news from the giant, ringed planet and its grand moon, Titan.

More information on the Cassini/Huygens mission...

AND, if you would like to build your own model of the spacecraft, you can download some plans and directions for free!

Stardust to Rendezvous With a Comet.

The spacecraft called Stardust has a mission unlike any other before; it will rendezvous with a comet, collect matter from the head of the comet, and return it to Earth!

Stardust was launched in February of 1999, and it will fly near the nucleus, the main body, of the comet called "Wild-2" in January of 2004. In January 2006, it will return to Earth with matter from the body of a comet. This will be the first time matter has been returned to Earth from beyond the Earth-Moon system.

Stardust will use a substance called aerogel to 'catch' particles from comet. The aerogel is one of the lightest substances known, and the particles will become lodged in the aerogel without being damaged, safely returning them to Earth for study.

Scientists are very interested in comets since they contain large portion of frozen water, as well as complex molecules. Many scientists believe that most of the water we have here on Earth was deposited as the Earth was bombarded with comets from the early days of the Solar System, and that many of the molecules required for life to form may have been deposited by comets, as well.

More on Stardust and its mission...

New Horizons to Pluto.

The mysterious, lonely little rock way out there in our Solar System, Pluto, will soon get a visitor! NASA has recently found money to fund the New Horizons spacecraft -- a spacecraft with the longest trip ever planned. New Horizons will actually be a pair of spacecraft, launching in 2006, and arriving near Pluto in 2015 and 2016.

Pluto has always been a curiosity. It spends much of its time in a part of space called the "Kuiper Belt", a large disk of objects at the outer edges of the Solar System. It's a bunch of matter that is just beyond the sweeping impact of the realm of the gas giants. Jupiter, Saturn, Uranus, and Neptune have captured as moons, or swallowed up completely, most of the matter beyond the asteroid belt -- but out past Neptune there are is another collection of rocky and icy matter that orbits the sun in huge sweeping orbits, and which never coalesced into anything of planetary size.

New Horizons will study Pluto, believed to be one of the largest Kuiper Belt objects, and its moon, called Charon. Charon and Pluto are often considered to be a sort of 'double planet'. They have the closet ratio of size when compared to any other planet and moon pair -- Charon is about half the size of Pluto. Also, when we look at The Moon from Earth, we always see only one side of it. What that means is, if you were standing on the moon looking at Earth, it would ALWAYS be in the same spot in the sky. Pluto and Charon take that to the next extreme: Pluto has one side that always faces Charon, and Charon has one side that always faces Pluto, as if they were tethered together by a giant cable. So, from Pluto, Charon stays in the exact same spot in the sky, and from Charon, Pluto never appears to move, either. It's a system unlike any other in the Solar System.

New Horizons will then go on to peer at other Kuiper Belt objects, studying their composition and formation -- and possibly giving us clues as to the origin of our Solar System.

To learn more about this marathon trek to the edge of the Solar System...

Planetary Update

We still have some great planets in view... and a great show approaching!

Saturn is still available at peak tilt for viewing its rings, but is only out for a couple of hours after the sun goes down. Look in the Western sky for one of the brighter points of light. It's still at about zero magnitude, so it's out right as dusk is ending. Soon Saturn will be leaving us for a while, so definitely use this month to check out this glorious planet -- it's the spring of a lifetime to see Saturn.

Jupiter is out for a little longer; from sunset until past midnight for most of this month. It is still the brightest object in the nighttime sky, apart from the moon. As Jupiter and Saturn are slightly lower in the sky, it is sometimes easier to track them with a telescope. Jupiter has been up near the zenith during what I find are the peak viewing hours, and sometimes it's hard to use a telescope pointed right to the peak of the sky. So, even though they are not in the sky for as long, Jupiter and Saturn are at a better part of the sky for viewing.

As Jupiter sets, our master of this summer, Mars, makes its appearance. It will be out during the morning hours all month, becoming 70 percent brighter, as it slowly moves to its closest rendezvous with Earth in over 60,000 years. Over the next two months it will get even brighter; in August it will exceed the glare that Jupiter has shed! By the end of May, a decent backyard telescope should be able to pick out a few variations of dark and light colors on Mars' surface.

Now that Saturn has given us peak viewing, it is stepping aside for what will be a glorious showing of Mars.

Constellation of the Month

Behind the Big Dipper is a giant of the Spring and Summer sky, though for some reason he’s not mentioned very much... it is The Herdsman: Boötes!

Attached to the newsletter is a layout of the stars. It contains one of the brightest stars in the spring sky -- Arcturus. If you know the Big Dipper, it is easy to find -- follow the curve of its handle away from the bowl of the dipper, a little more than a Big Dipper's length across the sky. There you will find the bright glittering Arcturus. Arcturus is in the evening sky, rising in the East, right in the early spring. Many cultures have used it as a marker as to when to begin planting.

Boötes

Boötes is usually referred as the man who keeps the Great and Little Bears in their place in the Northern part of the sky. "Arcturus" actually means "Bear Watcher" in Greek. "Arktos" is the Greek word for bear -- we can trace back the word "Arctic" to this root; the Northern part of the globe is literally the "land of the bears" -- a reference to Ursa Major and Ursa Minor, the Great and Little Bear constellations.

This month, Boötes is right in the East, laying flat against the horizon, basically as the attached picture shows. He is called The Herdsman, and a link to a picture showing the image we imagine is included below. I usually think of it more as a necktie, with the collar on the left side of the image, and the bottom of the tie on the right.

As we look at historical documents and artifacts, the earliest references to a pattern of stars in the sky making a picture relate to Arcturus and the other stars in Boötes. Some historians and astronomers consider Boötes the FIRST constellation. Since it has been around so long, and referred to in so many cultures, there are MANY stories involving him. Instead of trying to pick the best one, I will let you look through them all...

Check out a picture of Boötes, as well as a bunch of information and myths surrounding this very historical constellation.

The Moon

We have something to talk about this month -- a Lunar Eclipse!

This can only happen during a Full Moon, so it must happen near May 16. It will actually start to happen for us around 10:00 pm (EST) on the night of May 15. It should look a copper color during the eclipse, which will last about 3 hours.

We haven't had a full lunar eclipse since 2000; it's been a long wait for eclipse watchers. We won't have to wait quite so long for the next one, however -- it will occur in November of this year.

As the Moon goes around the Earth, and as the Earth goes around the Sun, sometimes we line up just right. If they line up on order of Sun, Moon, Earth, the Moon casts its shadow on the Earth, and from our point of view, the sun is blocked out and we have ourselves a Solar Eclipse. When the arrangement is Sun, Earth, Moon, as it will be on the night of May 15th into the early morning of the 16th, we see the Earth's shadow cast onto the Moon, which is what we refer to as a Lunar Eclipse.

The Moon's orbit is slightly tilted as compared to the plane of our Solar System, since the Earth is tilted on its axis. If the Earth were not tilted at all -- if we spun perfectly upright, like a top -- EVERY Full Moon would be a Lunar Eclipse, and EVERY New Moon would be a Solar Eclipse. Since the Earth-Moon system is tilted, eclipses only happen when the Moon crosses the plane of the Solar System at just the right time. AND, since it might not line up EXACTLY, that is why we sometimes get PARTIAL eclipses.

The phases for this month:

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