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Space/Astronomy: Most Popular Articles

These articles are the most popular over the last month.
Did You Know There Are 7 Different Types of...
When we think of stars we usually imagine our Sun. But the simple fact is that the Universe is made up of many different types of stars. In fact looking into the heavens most stars look very different, and some aren't really stars at all. So here is a run down of the most common types of stars in the galaxy.
Lunar Eclipses
When the Sun, Earth and Moon are aligned, the Earth will cast a shadow on the Moon creating a phenomenon known as a lunar eclipse. These events have been the subject of mythology and lore, but are readily explained by science.
10 Brightest Stars in the Milky Way Galaxy
Stars are massive shining spheres of hot gas, the closest of which is our Sun. Stars are primarily made of hydrogen, smaller amounts of helium, and trace amounts of other elements. Even the most abundant of the other elements present in stars (oxygen, carbon, neon, and nitrogen) are only present in very small quantities. Those stars which you see with your naked eye in the night sky all belong to the Milky Way Galaxy, the huge system of stars that contains our solar system.
10 Incredible (and Strange!) Astronomy Facts
Even though man has studied the heavens for thousands of years, we still know very little about the Universe we live in. And as we continue to learn more, we are consistently amazed, and sometimes confused, by what we learn. Here is a collection of amazing, interesting, and strange facts about our Universe.
Astronomy 101: Introduction to the Basics
Astronomy 101 - This basic Astronomy course was designed for those who have an interest in but little education in astronomy. Learn the basics of astronomy here.
The Big Bang Theory Explained
It was only recently discoverd that the Universe even had a beginning. Now, scientists are trying to solve the mysteries of the early Universe. The leading theory to explain how the Universe came into existence is known as the Big Bang theory. However, there are still many things that the Big Bang theory struggles to explain.
How is "Uranus" Pronounced?
The planet Uranus is one of the most beautiful objects in the night sky, especially as viewed through a telescope. Discussion of this object is often met with snickers and laughter because of how it is pronounced. But do people pronounce it correctly, or should it be said a different way?
The Surprising Origin of the Phrase "Once in a...
We've all heard the phrase. Space/Astronomy.
Top 10 Largest Stars in the Universe
Stars are immense balls of glowing plasma. Our Sun provides all the light and heat necessary for life to exist on Earth. And while the Sun is large in comparison to Earth, it is absolutely dwarfed by some of the stars that exist outside of our solar system. Following is a list of the 10 largest stars known in our Universe.
6 Things to Know Before Buying a Telescope
So, you want to know how to buy a telescope. Being a knowledgeable consumer is key Before you go shopping, learn as much as you can about telescopes. We will try to help you get started here, with the six things you need to know about how to buy a telescope.
What Exactly Is a Moon?
What is a moon? It's a simple question that may, on the surface, have an obvious answer. One has to do little more than look up in the night sky on clear evenings to see an example of such an object. But when it comes to defining these magnificent objects, the answer may not be so clear.
10 Things Everyone Should Know About Earth
Earth, our home planet, is the only planet whose name is not derived from Greek/Roman mythology. In Roman Mythology, the goddess of the Earth was Tellus - the fertile soil, while the Greek goddes was Gaia, terra mater - Mother Earth. The name we use today, Earth, comes from Old English and Germanic.
Eclipses and Human History
A look at eclipses and how people have observed and used them throughout our history.
Early History of Astronomy: Ancient Astronomers...
Early History of Astronomy. The study of our Universe is not new, the history of astronomy shows it to be the oldest science. People have been looking up, trying to explain the universe for as long as there have been people. Here, in lesson 1, we look at the early history of astronomy. We’ll look at ancient astronomers and their contributions to the history of astronomy.
10 Surprising Facts You Should Know About the Sun
Our Sun has inspired mythology in almost all cultures, including ancient Egyptians, Aztecs, Native Americans, and Chinese. Our Sun is actually the closest star to Earth. The Sun is a massive shining sphere of hot gas. The connection and interaction between the Sun and the Earth drive the seasons, currents in the ocean, weather, and climate.
10 Things You Need to Know About Mars
Named for the Roman god of War, Mars probably got this name due to its red color. It is sometimes referred to as the Red Planet. The name of the month March derives from Mars.
Discover the 10 Closest Stars to Earth
You can see thousands of stars when you look up at night. Here are the Top 10 Closest Stars to our solar system.
Should Pluto Be a Planet? Why the Debate...
In 2006 the International Astronomical Union stripped Pluto of its planet-hood, demoting it to dwarf planet status. But the debate has raged on ever since. So should Pluto be a planet, and in the end does it even matter?
Was the Apollo 13 Space Exploration Mission...
Apollo 13 was the 3rd scheduled lunar launch, carrying Jim Lovell, Fred Haize, & Jack Swigert to the moon. An explosion occurred, endangering the Apollo 13 Lunar Landing mission & astronauts Jim Lovell, Fred Haize, & Jack Swigert, the Apollo 13 space exploration mission became a race for survival. As NASA experts & contractors struggled to come up with solutions, the Apollo 13 astronauts; Jim Lovell, Fred Haize, & Jack Swigert; struggled to survive. The successful failure of space exploration.
Why Time Travel May Actually Be Possible
There have been times when I wish that I could revisit the past. Perhaps to undo a mistake, or to visit a hero of history. Time travel is an often used plot device in many science fiction works, but is there any science behind it? Is it possible to time travel into the past?
Solar System Tour - Visit Our Galactic...
Astronomy Solar System Tour, an Astronomy Guide to Space exploration close to home. Discover information on planets in our solar system. Find pictures of objects in our solar system. Learn more about our galactic neighborhood, our solar system.
Once Watery, Now an Icy Desert: Mars Has Changed!
The search for water and past oceans on Mars heats up with recent measurements of the Martian atmospheric water.
Everything You Need to Know About Venus, the...
Venus, the second planet from the Sun, is often referred to as Earth's Sister. While similar in size to Earth, the atmosphere is vastly different.
What Are Black Holes?
A favorite phenomenon of science fiction writers, black holes are real objects that play an important role in our Universe. Learn more about them here.
A New Look at Our Solar System
This isn't our parents' solar system anymore. In the last 50 years, our views of the Sun, planets, moons, rings, asteroids, and comets have changed with new discoveries.
An Introduction to the Pioneers and Branches of...
Astronomy, derived from the Greek words for star law, is the scientific study of all objects beyond our world, and the process by which we seek to understand the physical laws and origins of our universe.
Hanky-panky in Space?
One of the most popular questions fielded by astronauts posits the idea of sex in space. This article examines the physical issues around this touchy subject.
Constellations Pictures Gallery
Constellations information. Discover more about each of the 88 modern constellations. Find the names, information, and pictures of the 88 constellations.
Harvest Moon
September’s full moon, the Harvest Moon, has a special place in our agricultural history. Through most of the year, the moon rises each day about 50 minutes later than the day before. However, when the autumnal equinox approaches, the difference in rise times drops to about 25 to 30 minutes and even farther north, the difference is 10 to 15 minutes. As the Harvest Moon rises after sunset, this provides extra minutes of light each evening for farmers to work longer hours harvest their crops.
Why is Getting to Mars so Difficult?
In the late 1960's the United States proved to the world that it was possible to land humans on the Moon. Now, more than forty years later, the technology that took us to our nearest neighbor is quite antiquated. So with all our new advanced technology and innovation, why have we not ventured out beyond our Moon? How difficult is it really to send humans to Mars?
The Basics of Telescopes
Discover the basics of telescope astronomy with this guide. Telescopes come in three basic designs; Refractor, Reflector, and Catadioptric.
10 Things You May Not Know About Mercury
Named after the Roman god of commerce, travel and thievery, Mercury is the second smallest planet in the solar system, larger only than Pluto, the most distant planet in our solar system. If Earth were the size of a baseball, Mercury would be the size of a golf ball. Viewed from Mercury, the Sun would look almost three times as large as it does from Earth.
Basic Information about the Sun
The Sun provides energy for life to exist on Earth as well as the gravitational force to keep the planets in orbit. Here you will find basic information.
Does the Moon Rotate?
Does the Moon rotate? This question often confuses people, so let's take a look at what the Moon does.
What Kind of Telescope Should I Get?
The question is: What telescope should I buy for my friend/loved one/child/myself? Here are some thoughts about that, with some blunt advice on what NOT to do.
Top 7 Telescopes for Kids
Everyone has to start somewhere. Star your kids off right with quality telescopes at good prices. Check here for some great reflectors and refractors. Less expensive telescopes.
When Can We Expect to See Halley's Comet Next?
Comet Halley has stoked the interest of skywatchers for centuries as it returns to swoop around the Sun about every 76 years.
A Kids' Guide to the Sun and Planets
A collection of facts about the solar system for kids and students to learn and enjoy.
United States Astronomy Schools - Colleges and...
Guide to colleges and universities in the United States with astronomy degree programs. Learn where you can earn a degree in astronomy or physics with an astronomy track.
Challenger Explosion - A NASA Tragedy
When the Challenger explosion occurred, it shocked the nation, started a NASA investigation, and led to many changes in the shuttle program.
Is There a Dark Side of the Moon?
How many time have you used that phrase, dark side of the moon? At times, some people have been of the belief that one side of the moon was always dark, hence the phrase dark side of the moon. Is ther really a dark side of the moon? Read this article to learn the truth about the dark side of the moon.
How Did Neil Armstrong Become the First Man on...
It was July 20, 1969 when Neil Armstrong spoke what must be considered the most famous words of the 20th century,
What is a Planet?
What is a planet? It is one of the questions that I get most often in my astronomy class, and its a question that is at the source of great controversy. In 2006 the International Astronomical Union decided to answer that question and in doing so stripped Pluto of its planet-hood. The resulting fallout has caused rifts within the scientific community. All because of one, simple question: what is a planet?
Top 8 Telescopes Between 1000 and 5000 Dollars
If you have spent some time observing the sky with your naked eyes and a pair of binoculars, you may be ready to move on up to telescopes. As in most things in life, you typically get what you pay for. If you are looking for better telescopes to start out with, one which might carry you from a beginner to intermediate stargazer, check out these telescopes between $1000.00 and $5000.00.
10 Basic Facts About Uranus
Uranus is one of the most interesting objects in the night sky, and is absolutely beautiful to view through a telescope. Here we take a look at the top 10 most interesting facts about Uranus.
Sound in Space
Is there sound in space? It's a common question, and the answer is often misrepresented in film and television (though producers are getting better at dealing with this issue). Recently, the question has become even more cloudy with the release of CDs from NASA that contain tracks of the different sounds in space. How can this be?
Could a Gamma-ray Burst Destroy Life on Earth?
Gamma-ray Bursts (GRBs) are the most powerful events in the Universe. Despite being far, far away in distant galaxies, their radiation is detected - in significant quantities - here on Earth. This begs the question, could a GRB destroy life on Earth, particularly if it happened nearby?
What Are the 10 Closest Stars to Earth?
Naturally our Sun is the closest star to Earth. But beyond that most stars seem impossibly far away. But how close are our nearest neighbors. Here we take a look at the ten closest star systems to Earth.
What Happens to the Human Body in a Vacuum?
class="no-js" itemscope itemtype="http://schema.org/Article" > itemprop="description" >In the 1981 movie
Top 10 Quotes by Neil Armstrong, the First Man...
Neil Armstrong is unequivocally an American hero. His bravery and skill earned him the honor of the first human to ever set foot on the Moon. As a result Neil Armstrong has been looked to for insight into the human condition as well as commentary on the state of technology and space exploration. Here we look at the top ten Neil Armstrong quotes, to see how he has influenced our nation and world.
Can Women Get Pregnant in Outer Space?
If mankind is ever to conquer the cosmos it will be necessary for humans to procreate in outer space. But it turns out that this is currently easier said than done. There are significant barriers that stand in the way of women getting pregnant in space. The most immediate impact will be on any future plans to send astronauts to Mars for an extended stay.
Astronomy and Space FAQs
Browse these Frequently Asked Questions About Space & Astronomy. Learn the answers to Astronomy Questions & Space Questions This feature of our Basics Series; What You Need To Know About Space provides answers to astronomy questions and space questions. Discover the answers to some frequently asked questions about space.
Defining the Cosmological Constant
The Cosmological Constant was once thought to be a way around a difficult problem in cosmology. Then it was though to be a mistake. Now, a new version might help explain a mystery in astronomy.
Did NASA Find the Missing Day from the Bible?
We've all received emails that make fantastic claims. Most of the time they are fantasy, or full of half-truths. One such email that has made the rounds claims that NASA discovered the missing day from the Bible. Is there any truth to the story, or is it a bunch of hogwash?
Matter-Antimatter Power on Star Trek
Aboard the famed Starship Enterprise from the television series Star Trek the propulsion systems are energized by a matter-antimatter power plant. Is such a thing even possible? Could we ever build such a device and use it to power starships?
Discover the Heliocentric Theory, or Sun-center...
Discover the Heliocentric theory and how Nicolaus Copernicus made it popular.
More Songs About Space from Pop Music
Top ten rock - pop songs with a space theme including lyrics. These rock - pop songs including lyrics are all dedicated to the space age. Page 2.
The Brightest Star in the Nighttime Sky
Sirius, also known as the Dog Star, is the brightest star in the sky. Learn more about it here.
Does Life Exist Elsewhere in Our Galaxy?
The search for life outside our tiny blue rock has consumed the imagination of man for decades. But now, with increasingly advanced technology we may finally be on the verge of discovering where else life may exist in our galaxy. The more we search, however, the more we realize that life may be rather precious after all.
Astronomy 101 - Modern Astronomy
Astronomy 101 - Modern Astronomy - Lesson 3: Astronomy Enters the Twentieth Century
What is the Doppler Effect?
The doppler effect is a phenomenon by which a source's radiation appears to be of higher (blueshifted) or lower (redshifted) energy than it really is. This is caused by the object's motion relative to the observer, and is an important tool in astronomy as we try to understand the Universe.
How Many Habitable Planets are in the Milky Way...
There are a vast number of stars in the Milky Way galaxy, and recent data suggests that many of them have planets orbiting around them. But how many of these would we expect to be fit for life, and how many of these will actually contain life? The answers are not so simple.
Red Supergiant Stars
The largest stars in the Universe are red supergiants. The creation and evolution of these behemoths is an active area of research among scientists. It is believed that high mass stars eventually evolve into supergiants once they leave the main sequence and that, eventually, they will brilliantly explode in a massive supernova.
You are Descended from Astronomers
An opinion piece about five of the many, many reasons humans study the sky.
Red Giant
Once stars like our Sun have exhausted the hydrogen fuel in their cores their cores will compress and heat up. This action causes the energy generated by the increasing temperature to expand the outer envelope of the star, creating a Red Giant.
Top 8 Telescopes Between 500 and 1000 Dollars
If you have spent some time observing the sky with your naked eyes and a pair of binoculars, you may be ready to move on up to telescopes. As in most things in life, you typically get what you pay for. If you are looking for better telescopes to start out with, one which might carry you from a beginner to intermediate stargazer, check out these beginner's telescopes ranging from $500 to $1000.
Have Aliens Walked Among Us?
For decades man has wondered if beings have another world have walked among us. Is it possible? Or is it simply science fiction? What about the evidence out there, is any of it credible. These are questions that we will explore.
Astronomy and Space Timeline
Astronomy and Space History Timeline. The history of astronomy and space exploration timeline.
Top 10 Astronomy and Space Weblogs (Blogs)
According to Sheila Ann Manuel Coggins, the About Guide to Weblogs, the definition of a Weblog or Blog
Free Sky Maps - Cities Around The World
You can view free sky maps as seen from various cities around the globe. Your Guide offers this online planetarium which gives you three ways to view the sky and produce free sky maps.
Meet a Nearby Sun-like Star
Epsilon Eridani is a nearby star that has long fascinated astronomers. Let's take a look at this star and its giant planet.
Blue Moon
Blue Moon. Once in a blue moon. You have probably heard this expression before. It usually means not very often. But, is there really such a thing as a blue moons? Well, yes, but it's probably not what you may think, and a blue moon is definitely not what it used to be.
Astronomy 101 - Astronomy History - Seeing Is...
Astronomy 101 - Astronomy History - Seeing Is Believing - Lesson 2: History - A Renaissance in Science
NASA Acronyms - S Acronyms
NASA Acronyms and their meanings - S Acronyms. Did you ever wonder what those strange conglomerations of letters meant? Here's your chance to find out what those NASA acronyms stand for. From Standard Earth Observation Satellite to Support and Logistics Areas - Shuttle Landing Facility to Shuttle Imaging Microwave System.
Astronaut Costumes for Adults
Want an astronaut costume? From Halloween to costume parties to plays or skits, any time you need a costume, check out these space related costumes ideas for adults. From astronaut costumes to alien costumes ideas.
What are Rotation and Revolution?
Rotation and revolution are vital to the study of astronomy, as virtually all heavenly bodies undergo some rotational dynamics of some sort. But what are rotation and revolution exactly, and how are they different?
One of the theoretical consequences of general relativity is the existence of regions of space known as wormholes. While it is not completely understood how such places are created, there is currently no observational evidence to prove that they do, they could provide a means of traveling across the Universe nearly instantaneously. So what is this mysterious phenomenon and will we ever be able to harness their potential?
Exploring the Universe
Man has always been fascinated by the heavens. Even before man knew what was out there he has thought about walking among the stars. Science fiction has revolutionized the way that we think about space exploration. And now that science is beginning to make giant leaps forward, it may not be long before science fiction becomes a reality.
NASA Discovers a New Planet In Our Solar System
Literally Planet X, especially if you use Roman numerals. NASA scientists have discovered a 10th planet in our solar system. The planet, larger than Pluto, was discovered using the Samuel Oschin Telescope at Palomar Observatory near San Diego, Calif. The discovery was announced today by planetary scientist Dr. Mike Brown of the California Institute of Technology in Pasadena, Calif., whose research is partly funded by NASA.
Supernovae (plural form of supernova) are the most violent events in the Universe. The energy emitted during an event can outshine an entire galaxy of billions of stars. The result of a massive star dying, they are fascinating to study, and brilliant to behold.
Earth: Learn About our Place in the Solar System
Learn the basics about Earth -- our home planet and the only planet in the solar system known (so far) to support life.
How Are Astronomy, Astrophysics, and Astrology...
A comparison of the terms astronomy, astrophysics and astrology. Often confused, the differences and similarities are analyzed and discussed.
Check out astronomy and space-related magazines!
These magazines provide good sources of information about astronomy and stargazing, and most have online presences too.
Touring Mars with Curiosity
A look at the Mars Curiosity Rover's first Mars year on the surface of the Red Planet.
Will the U.S. Really Stop Sending People to...
It's been nearly 40 years since man last set foot on the Moon. Will man return? Will we venture onto more distant worlds? Well NASA has been commissioned with a new vision, and it is one that will take man to worlds beyond our own.
Peeking into the Core of the Milky Way Galaxy
Astronomers are using unique techniques to look at objects in the center of our Milky Way Galaxy in different wavelengths of light.
Constellations Pictures - Andromeda - Picture...
Andromeda, daughter of Cepheus and Cassiopeia. - Genitive: Andromedae Abbreviations: And, Andr Right Ascension, (h): 1 Declination, (deg): 40N
10 Interesting Facts About the Planet Venus
Venus is a planet that has fascinated people for centuries. Modern scientific studies show that it is not a habitable planet.
Neutron Stars
Supernovae are some of the most dynamic events in the Universe. They create such intense explosions that the light that they emit can outshine entire galaxies. But the compact objects that are left behind are also incredibly powerful as well.
Main Sequence Stars
Not all stars are the same; some are smaller, some are larger, some are red, some are blue. While these stars may be different in a variety of ways, they all spend most of their lives on what is known as the main sequence. Here, stars fuse hydrogen into helium to sustain themselves, but when that hydrogen runs out, these stars can lead vastly different lives.
The Science of Star Trek
One of the most popular science fiction series of all time is Star Trek. In it, future inhabitants of Earth take off on quests to the far reaches of the galaxy. Using advanced technologies like warp drive and artificial gravity, the occupants of the starship Enterprise explore strange new worlds. But is it all just science fiction, or is there some science fact in the mix?
Microwave Radiation
The microwave band is actually a subset of the broader radio band. But when the term
Were the Apollo Moon Landings a Hoax?
Over the last several decades the Moon landings of the late 60s and early 70s have garnered much scrutiny. Some have argued that it would have been physically and technologically impossible to land men on the Moon and return them home. Was it all a hoax? I'll discuss the claims of the conspiracy theorists and let you determine for your self if man really landed on the Moon. Did you think of an issue I didn't address? Send me an email and I will be sure to add it.
Is There Such a Thing as a Planet Sound?
: Is There Such a Thing as a Planet Sound? You can go on eBay right now (NASA has stopped producing copies
Supermassive Black Holes
Supermassive black holes are some of the most powerful objects in the Universe. These incredible objects hold entire galaxies together and are capable of releasing incredible amounts of energy. Their formation is still a mystery. And some believe they may hold the key to exotic subjects of science fiction like interstellar travel and, possibly, time travel.
Earth Pictures - Full Earth
View of the Earth as seen by the Apollo 17 crew traveling toward the Moon. This translunar coast photograph extends from the Mediterranean Sea area to the Antarctica South polar ice cap. This is the first time the Apollo trajectory made it possible to photograph the South polar ice cap. Note the heavy cloud cover in the Southern Hemisphere. Almost the entire coastline of Africa is clearly visible. . Page 12.
The Southern Hemisphere Sky Boasts a Bright...
Canopus is the second-brightest star in our sky and the brightest in the constellation Carina. If you live far enough south, you can see it along with Sirius.
The Untold Story of the Teacher Who Died on the...
On January 28, 1986, the world lost one of its greatest resources, Christa McAuliffe, the space shuttle Challenger astronaut teacher.
Astronomy Science Fair Projects Ideas
Astronomy Science Fair Projects Ideas. Take a look at these astronomy science fair projects ideas to see if they can help you come up with your own plan.
Space Shuttle Challenger Disaster - A NASA...
The Space Shuttle Challenger disaster, a NASA tragedy. When the space shuttle Challenger exploded killing all aboard, it shocked the nation, started a NASA investigation, and led to many changes in the space shuttle program. Page 2.
The Milky Way Galaxy
Our little corner of the cosmic neighborhood: The Milky Way Galaxy. Our understanding of our home is evolved over time, and is just now really coming into focus. So what is the Milky Way Galaxy and what do we really know about it?
11 Things About Jupiter You Probably Didn&rsquo...
Jupiter, the king of the planets, is the largest and heaviest of the planets in our solar system. Perhaps best known for the giant red storm on the surface, Jupiter has many features that may surprise people. So check out our list of the most interesting facts about Jupiter.
Space Firsts - Basics
Space Firsts - Space Basics - Firsts In Space exploration - Space Firsts - Basics Series; What You Need To Know About Space. Discover who did what and when in these space firsts. From the first Earthling in space to the first man on the moon.
The Origin of Our Solar System
There have been no shortage of theories as to how our solar system formed. But it is now believed that the solar system formed from the collapse of a giant solar nebula some 4.5 billion years ago.
Full Moon Names
Learn more about the full moon names that people have used throughout the year.
Stargazing Takes You "Out There"!
Some musings about astronomy as a science and as a pastime, for people who are interested in any aspect of stargazing: from casual observing to serious scholars.
What do you NEED To Do Astronomy
Let's muse about the things you need to go stargazing. It might be less than you think, and when it comes time to buy something, you'll have some information to help you decide.
Meet the Star Closest to the Sun and Earth
Come learn about Proxima Centauri, the closest star to our Sun at the present time.
Star Names - How Did Stars Get Their Names?
Star names can sometimes sound cryptic, or at the very least - unusual. While other times star names can sound familiar. Stars get their names through several different means, but often names arise out of traditional conventions from ancient cultures. Called proper names (sometimes also known as traditional, popular or common names), this is how many stars have gotten their names over the centuries.
Safely Viewing Solar Eclipses
Your eyes are very important and are also very vulnerable. We've always been told that looking directly at the sun is unsafe. So is looking at the sun during most eclipses. It is only safe to do so during the few brief seconds or minutes of a total solar eclipse. Partial eclipses, annular eclipses and the partial phase of a total aclipse are never safe to vew directly without taking precautions. Failure to use appropriate filtration may result in permanent eye damage or blindness!
The Biography of Nicolaus Copernicus
Disputer of the Ptolemaic System. Creator of the Copernican System. Read the biography of Nicolaus Copernicus.
Dwarf Planets
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Volcanic Venus Surprises Scientists
Recent studies of the surface of Venus have revealed volcanic hotspots, proving that the planet is still active inside.
Time Travel
Nearly all of us have wished, at one time or another, that we could travel through time. Whether it is to correct a mistake in the past, or to fast-forward to a much anticipated future event, the lure of time travel is unmistakable. But what does science say about time travel? Come along as we see whether it is possible to travel into the future.
Ptolemy Biography
Ptolemy (aka Claudius Ptolemaeus, Ptolomaeus, Klaudios Ptolemaios, Ptolemeus) lived in Alexandria, Egypt. We know very little of Ptolemy's life, including his birth and death dates. He was an astronomer, mathematician and geographer. Ptolemy created the Ptolemaic System - Earth Centered Universe.
Pluto Picture - Pluto in True Color
Pluto is mostly brown. This picture captures the true colors of Pluto as well as the highest surface resolution so far recovered. No spacecraft has yet visited this most distant planet in our Solar System. The above map was created by tracking brightness changes from Earth of Pluto during times when it was being partially eclipsed by its moon Charon. The map therefore shows the hemisphere of Pluto that faces Charon. Page 8.
Blue Supergiants
When massive stars leave the main sequence they usually become red supergiants. However, they will tend to oscillate between various other supergiant stages, including becoming a blue supergiant. In this phase the star is smaller, yet hotter than the other supergiants.
The Top 10 Most Massive Stars
The Milky Way Galaxy is filled with hundreds of billions of stars. And the Milky Way is only one of billions of galaxies. Some of these stars are only a fraction of the Sun's mass, while others are equivalent to hundreds of Suns. So what are the 10 most massive stars in the Universe?
The Planet Uranus
The planet Uranus is the seventh planet from the Sun, and while it does have some commonalities with its neighbor Neptune, it is also very unique in many ways. This large, gaseous, somewhat icy and undeniably beautiful planet has been acknowledged for millennia, but was curiously re-discovered in 1781 by Sir William Herschel.
Visit Neptune: The Most Distant Planet
Neptune is one of the most interesting objects in our solar system . It shares similarities with its
What is Matter?
Matter is all around us, it is the physical material of the Universe. But there is more to matter than just mass.
All About the Moon
Man has wondered about the Moon since the dawn of reason. But it has only been in the last several decades that we have come to truly understand the Moon's nature and beginnings. Come and explore the most interesting facts about the Moon.
Should We Return to the Moon?
It has been over 37 years since man has set foot on the Moon. Recently NASA began making preparations for our return. But is this a good idea? Is it worth risking human life for such a dangerous undertaking?
Constellations Pictures - Antlia - Picture of...
The Water Pump - Genitive: Antliae Abbreviations: Ant, Antl Right Ascension, (h): 10 Declination, (deg): 35S . Page 2.
White Dwarfs
Stars evolve along different paths dictated by their mass. Stars like our Sun will eventually leave behind a stellar remnant known as a white dwarf. But what are these objects?
Top 3 Telescopes Over \$10,000.00
Are you ready to move on up to a better telescope? As in most things in life, you typically get what you pay for. Do you want to become a serious amateur or even a professional? Check out these telescopes over $10000.00. With these telescopes, portability is definitely less of a factor. In fact, if you have plans to build your own observatory, here's the place to start.
Top Toy Planetariums
You'll have a stellar time learning about our solar system and the stars with these home planetariums. All you need is a dark room and an imaginations (and batteries of course). Help your kids begin their journey into astronomy with some great educational toys.
Top 10 Astronomy Books for Adults
Check out these top astronomy books for adults. Find astronomy books to complete your knowledge and library. From the basics through telescopes, these astronomy books will give you the insight you need.
Meet Mae Jemison: Doctor, Astronaut, Star Trek...
Dr. Mae Jemison was the first African-American female astronaut in Space. Read her brief biography.
The Sun's Hot Little Mystery
A look at how tiny flares on the Sun may be heating its outer atmosphere.
Does the U.S. Military Have a Secret Space...
The speculation of several television series, the concept of a secret military shuttle program is intriguing for sure. But is there any truth to it?
The Astronomer with the Brass Nose
Tycho Brahe was the Danish Father of Modern Astronomy. His work inspired new generations of observers to learn more about the cosmos.
Finding the Fascinating Dwarf Planet
The Texas-sized asteroid Ceres, about 930 kilometers (580 miles) across, was the first asteroid ever detected. Learn more about its discovery.
Moon Pictures Gallery
The Moon is the only natural satellite of the planet Earth. It was known as Luna to the Romans, Selene and Artemis to the Greeks, and many other names in other languages.
Earth Pictures Gallery
Discover Earth Pictures and images in this Earth Pictures Gallery. These Earth pictures are awe inspiring and tell a story about our home planet, Earth.
Who Really Invented the Telescope? (Hint: It...
So, who did invent the telescope? Learn this and other space and astronomy-related frequently asked questions here.
luminosity brightness light electromagnetic...
When we see stars in the night sky we are observing the radiation that escaped from their surface hundreds, thousands and perhaps millions of years ago. In order for us to be able to see such distant objects, these stars must emit massive amounts of energy. The measurement of this energy release is the luminosity.
Saturn - Ringed Planet - 6th From Sun
Saturn - Pictures and Astronomy Facts - Solar System Planetary Astronomical Data and Images of Saturn. Saturn. Astronomy Guide to Space exploration close to home. Information on our solar system. Saturn planetary data and graphics.
Moon Phases - Yearly Moon Phases Through 2025
Moon Phases From New Moons to Full Moons - Yearly Moon Phases Through 2025 Below are the moon phases
Earth Pictures - Earth Globe
Earth Globe 11/20/1998 . Space / Astronomy. Page 17.
Learn about Mars!
Mars Information. Astronomy Guide to Space exploration close to home. Information on planets in our solar system. Information on Mars, the red planet.
Composition of the Universe
One of the major revelations of the last quarter century is that there seems to be more that we don't see, than what we do. We throw around words like Dark Energy and Dark Matter, but what are these things and what role do they play in the composition of the Universe?
Remembering Ronald E. McNair
Biography of Ronald E. McNair (Ph.D.) - NASA Astronaut (Deceased). Space Shuttle Challenger STS-51L Mission Specialist Ronald E. McNair
Is Dark Matter Real?
We thought that we were so close. Einstein's theories of relativity gave us a framework to explain the motion and dynamics of the Universe on a large scale. But as we sought to apply his equations to the motion of galaxies we found that the equations didn't match the data. So either relativity theory is wrong, or some other mysterious forces are at play. But which is it?
The Straight Scoop on Star Brightnesses
Magnitudes -- measures of brightness -- help us understand how bright things are that we see in the sky.
How Do We Stop Asteroids from Destroying Earth?
The threat of a large asteroid or comet colliding with Earth is very real. How will we stop the destruction of Earth? Is there a plan to combat the, potentially, greatest threat to life on Earth?
Mars Astronomy Pictures Gallery
Named for the Roman god of War, Mars probably got this name due to its red color. It is sometimes referred to as the Red Planet. The name of the month March derives from Mars. Known since prehistoric times, Mars is still a favorite of choice for human exploration. The density of Mars is about 30 percent less than that of Earth (3.94 g/cm3 vs. 5.52 g/cm3).
Meet an Early Greek Astronomer
Early Greek astronomers such as Aristarchus began humanity's attempts to learn more about the cosmos and our place in it.
Top 8 Nonfiction Space Books Guide
These Nonfiction Space Books make for great reading for anyone interested in Space Exploration, NASA, and the history of the Space Age. Discover what it's like to be an astronaut. Follow the adventures of astronauts and engineers from the space race through modern space exploration and in the future, possibly to the stars. Follow as the astronauts guide us into space.
Earth Pictures - First View of Earth from Moon
The world's first view of Earth taken by a spacecraft from the vicinity of the Moon. - The photo was transmitted to Earth by the United States Lunar Orbiter I and received at the NASA tracking station at Robledo De Chavela near Madrid, Spain. This crescent of the Earth was photographed August 23, 1966 at 16:35 GMT when the spacecraft was on its 16th orbit and just about to pass behind the Moon. . Page 13.

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