How Unnaturally Natural

What could be more unnatural looking than this shot of an open cluster of stars, an emission nebula, a reflection nebula, and a dark nebula all interacting in the constellation Sagittarius.

"Whoa, back up a bit," you must be saying. "Emission nebula? What's that?"

In side of that picture of Trifid Nebula, there is a lot going on. This picture by the way was taken in the night sky over Abilene, Texas.

But to answer your question, we should look at each individual thing in this picture.

This is the Rosette Nebula in the constellation Monoceros (mo-nos-er-os). The nebula surrounds a young star cluster. This nebula is emitting its own light, due to the presence of ultraviolet radiation from the very hot young stars that make up the cluster. This radiation, although not visible to the eye, is strong enough to 'excite' the atoms in the interstellar dust and gas so that they 'jump' to different energy levels and emit their own form of radiation which can be seen in the nebula's light spectrum. It is not simply reflecting the light from the cluster.

But a reflection nebula does. Reflection nebulas reflect light from a nearby star. Many small carbon grains in the nebula reflect the light. The blue color typical of reflection nebula is caused by blue light being more efficiently scattered by the carbon dust than red light. The brightness of the nebula is determined by the size and density of the reflecting grains, and by the color and brightness of the neighboring star(s).

Dark nebula, also seen in that first picture. This is a good example of a dark nebula, which is one that is blocking the light from whatever is behind it (which could make a shape - in this case, a horsehead).
You will find these in an emission nebula, which as I should have mentioned is a cloud of a high temperature gas. The atoms that are in the cloud get energized by light from a close star. These types of nebulae are usually red because of the amount of hydrogen.

Pacman

Yes its true, I do like the idea of a telescope in space, cutting through all of the fuzziness of the night sky, out there in the cold darkness of space. When I post pictures of what the Hubble has done, I am ignoring what some folks are doing right in our own backyard.

If you think about it Junior, this is where you most likely will have your greatest moments starring at the sky. Although, you are on the verge of a time when you may be able to be a space tourist. Possibly even to the Moon.

This photo was done by a guy named Greg Morgan from Clovis, California. Officially called NGC 281 it is approximately 10,000 light-years away, give or take a few hundred light years in the constellation Cassiopeia. It is sometimes called the Pacman Nebula.

Hubble is still busy!

I caught a show on PBS the other night that was all about the Hubble repair. It was amazing how many tools they had to invent, how much training went into it (they actually practice in a shuttle sized pool) and how one mistake, like a lost screw would have made the mission all for nothing.



If you are interested - and I sure hope you are, you can watch the whole show here! Get some popcorn and a drink and settle back in your chair. This is amazing stuff!

Hubble Snaps some Cool Shots

Remember when I told you about the Hubble mission and the update it was receiving. I told you how this would be the last time - even though what these astronauts did will last the massive telescope a decade.

The first shots are up and posted. This is one of the Butterfly Nebula
It's colorful "wings" are actually cauldrons of heated gas ejected from a dying star that was once about five times the mass of the Sun. The star is now discharging a stream of ultraviolet radiation that makes the cast-off material glow.

This is Omega Centauri.

There are about 10 million stars here. Most of the stars seen here are white-yellow, similar to our Sun. The orange stars are further into their lifecycle, having become larger and cooler. They'll continue to cool and expand in size, eventually becoming red giants seen here as the bright red dots.

This is Stephan' Quintet. Don't be fooled into thinking that they are all right together. They're not.

The galaxy in the upper left is believed to actually be seven times closer to Earth than the rest of the group. The three other galaxies have distorted shapes, elongated spiral arms, and gaseous tails as evidence of their close proximity.

Here are the high resolution shots.

Saturn animation

It has been awhile since I posted here and I apologize for that. Life interrupts a good deal of my best intentions - as you will find out as you grow up and grow older Junior. I just hope that your interest in the night sky will not wane in the process. Building on what you know at age twelve is a lot easier than trying to build on your knowledge at age 52 - not impossible just harder.

Here is a link to a great Saturn animation I found that might interest you. It was compiled over a six year period.

Mars, finally

I will never stop marveling at what new technology can bring. For you, it is as natural as waking up. The latest comes from Google Earth, which your dad should download for you here.

Here is what it will shows of Mars. Yes, Mars!


And if the clouds ever clear, you need to check this out this weekend. And tell me about when I get here next week..

Tripping the Light Fantastic

As you look at those stars on the night sky, you should always keep in mind that what you are seeing is what happened a long time ago. For hundreds, if not thousands of years, geniuses such as Einstein and Isaac Newton and even further back to ancient Greeks and Persians wondered about light. For a really long time, it was believed that light could travel at any speed through space because, in those days, before telescopes, ancient stargazers believed that there was nothing to block the light. So they thought it could speed up and slow down.

But now we know differently. Space is not as empty as everyone once believed and the speed of light is one of those amazing things that stays the same, no matter what. This is a good thing if you think about it for a second. Because light can be counted on to behave the same near earth as it does billions of miles away, we can make predictions about what to expect.

Consider this image, done to simulate exactly how fast light travels from the Earth to the Moon. It takes 1.25555 seconds. The light from the sun takes eight minutes to get to us.

I remember you telling me what you learned when you did that project on Einstein a couple of years back. You told me that light traveled 186,242.4 miles a second. How fast is that? Suppose you were shine a light from Bend to New York on the other side of the United States. That beam of light would travel back and forth 60 times in a second.

This galaxy is the farthest light has traveled, measured by Hubble at 13 billion light years away. The universe was only a billion years old when this galaxy (on the right) began to send its light out, so long ago, the earth wasn't even here yet. Because that is so fast, it is almost impossible to imagine. Look at your Mom across the room. What you are seeing is not what you think. It actually happened 20 billionth of second ago. Now imagine that our Milky Way is 100,000 light years across. In terms of galaxies, that's not very large. But it does require a very large imagination to try and picture that king of event.

This is the closest galaxy to us at 42,000 light years away.

Never to be Seen Again

The last time I wrote, we were talking about the amazing things that the Hubble telescope had seen in its time in space. Often referred to as the people's telescope, the Space Shuttle not only successfully grabbed the telescope in space - with all kinds of really dangerous space junk floating around - but repaired it. When they were done, they simply released it. It will never be seen by humans again.

Here are the pictures of that mission.

A Fresh Look at Deep Space

This past week, the last space shuttle mission visited one of the most exciting accomplishments in modern science, the Hubble Telescope. Unlike the ground based telescope you use, this look into space does not have all of the interference of light (remember how I explained that light from the city takes some of what you are looking at and makes it harder to see) and the stuff floating around the upper atmosphere (the layers of air and gases that protect our planet from harmful rays from the sun). The views without these problems are simply awesome.

The mission these astronauts were given was basically a repair and replace job. There were several systems that had broken down over the years and need to be fixed. But even more importantly was the job of replacing the 16 year old camera.

Among the new camera’s features is the ability to record images in the normally invisible ultraviolet and near-infrared wavelength bands of the electromagnetic spectrum, as well as in visible light. The infrared capability extends Hubble’s reach into the past because the expansion of the universe stretches the wavelengths of light from distant galaxies to longer, redder wavelengths.

Light comes in waves, some you can see and others you cannot. This new camera can see what your eyes would not. Ultraviolet (UV) light has shorter wavelengths than visible light. Though these waves are invisible to the human eye, some insects, like bumblebees, can see them! So can Hubble. This is a look at how this telescope sees things in space differently than the human eye.

Scientists have divided the ultraviolet part of the spectrum into three regions: the near ultraviolet, the far ultraviolet, and the extreme ultraviolet. The three regions are distinguished by how energetic the ultraviolet radiation is, and by the "wavelength" of the ultraviolet light, which is related to energy.

The near ultraviolet, abbreviated NUV, is the light closest to optical or visible light. The extreme ultraviolet, abbreviated EUV, is the ultraviolet light closest to X-rays, and is the most energetic of the three types. The far ultraviolet, abbreviated FUV, lies between the near and extreme ultraviolet regions. It is the least explored of the three regions. FUV is what Hubble, with its new camera will be able to see.

Our Sun emits light at all the different wavelengths in electromagnetic spectrum, but it is ultraviolet waves that are responsible for causing our sunburns.

The telescope was named after Edwin Hubble, who took many photographs through 100 inch reflecting Hooker telescope, proving they was lots of stuff beyond our own galaxy, and determining the existence of several other galaxies such as our own milky way, which had until then been believed to be the universe.

Hubble had also devised a classification system for the various galaxies he observed, sorting them by content, distance, shape, and brightness; it was then he noticed redshifts in the emission of light from the galaxies. What he saw was that these galaxies were moving away from each other at a steady rate equal to the distance between them. From these observation, he was able to formulate Hubble's Law in 1929, helping astronomers determine the age of the universe, and proving that the universe was expanding.

Hubble once said: "Equipped with his five senses, man explores the universe around him and calls the adventure Science."


Below are pictures taken by this telescope.

What We Take for Granted

You have grown up with the internet, making this discussion of the night sky over Bend, your hometown possible from three hours drive away. And you are growing up in a time when what should seem fantastic, just because it was just a few short years ago for people like your Dad and even more so for me, seems almost ordinary.

Today, because I know your night sky will have one too many clouds in it, we will talk about a special space craft visiting place I know I'll never visit - but you might someday! Cassini spacecraft entered orbit around Saturn to begin the first in-depth, up-close study of the ringed planet and its domain (moons and rings and such). It has been in this orbit for over four years and now is doing some additional sightseeing.

This part of the extended mission called the Cassini Equinox Mission.

"We're looking at a string of remarkable discoveries -- about Saturn's magnificent rings, its amazing moons, its dynamic magnetosphere (how it acts like a giant magnet holding the rings and the moons where they are) and about Titan's surface and atmosphere," says Dr. Linda Spilker, deputy project scientist. Can you imagine a job where you get to do this everyday?

Dr Spilker went on to say, "Some of the mission highlights so far include discovering that Titan has Earth-like processes and that the small moon Enceladus (which Cassini flew past at only thirty miles from the surface)has a hot-spot at its southern pole, jets on the surface that spew out ice crystals and evidence of liquid water beneath its surface."

Cassini's observations of Saturn's largest moon, Titan, have given scientists a glimpse of what Earth might have been like before life evolved. They now believe Titan possesses many parallels to Earth, including lakes, rivers, channels, dunes, rain, snow, clouds, mountains and possibly volcanoes.

The spray of icy particles from the surface jets collectively forms a towering plume three times taller than the width of Enceladus. It is now thought that the plume feeds particles into Saturn's most expansive ring, the E ring. Already in the extended mission, the spacecraft has come as close as 25 kilometers (15 miles) from the moon's surface.

The extraordinary results from the Cassini spacecraft and the European Space Agency's Huygens probe, which plunged through Titan's dense, smoggy atmosphere to its surface, have generated hundreds of scientific articles and been the subject of special issues of the world’s most important scientific journals.

This picture of Saturn was taken on April 27, 2009 and received on Earth April 28th, 2009. The camera was pointing toward SATURN at approximately 987,316 kilometers away.

The first four years of the Cassini-Huygens saga brought a new dimension of understanding of the complex and diverse Saturn system. The two year Cassini Equinox Mission is expected to be just as exciting. During the extended mission the spacecraft will make 60 additional orbits of Saturn, including 26 flybys of Titan, seven of Enceladus, and one each of Dione, Rhea and Helene. Investigations of Saturn's rings, the planet itself and new places within Saturn's magnetosphere await.

Why is it called Cassini?

It could have been a star!

Few of us think of a planets as much more than rocks n space, round, with orbits around a sun. Jupiter, our largest planet needed just a little more mass to be a star. But what is mass?

Mass on earth is easy to figure out. Simply weigh it. Because gravity is even, when one thing weighs more, it has more mass. Size has nothing to do with it. If you blow up a balloon to be larger than your brother's head, Martin's head will still weigh more. So when we talk about Jupiter needing a little more mass, if it was eighty times more dense, it would have had enough of the stuff to make it a solar system.

At last count, Jupiter has 49 moons. Galileo, who discovered it using a primitive telescope thought the moons he saw were stars. (Here is a list of the names of Jupiter's moons) As cool as it looks, it would not be a very nice place to visit. The gravity would squash you. It is 20,000 times that of earth!

Made up of ammonia gas and beneath that hydrogen that, because of that gravity, has turned to liquid. And deep inside Jupiter, at the very center is a solid core. In fact, the core of Jupiter is one big, earth sized magnet.

One of its moons, Io, is the most volcanically active objects in our solar system. Ganymede is also the largest moon in our solar system.

I hope you get to see it.

Here are some other things you should be looking for on a clear night during the month of May.

The Story of the Constellations

I hope you are enjoying your spring break but like so many spring breaks in Oregon, the clouds are what you see when you look toward the night sky. But it won't last for long. So I thought I'd take a moment and talk about the constellations.

In my last post on the Big Dipper, part of Ursa Major or the Great Bear, I pointed out what to look for when you do get to see it.

There is a story for every constellation in the sky. Before we had access to all of the information we now get from television and computers, ancient people (much older than me) told stories, watched the skies for changes in the seasons and marked their lives with the passing of these star formations in the night sky.

Here are just a couple of reasons why these stars were so important. In ancient times, when the months were the annual calendar, people studied astronomy to help them know when to plant and when to harvest. They knew when the rivers were likely to overflow...the Egyptians noted that the cycles of the Dog Star, Sirius, coincided with the rise and fall of the Nile River. They could accurately predict the Nile floods using just the stars in the sky!

Some of the Native American cultures here in North American had a different story. They noted that when the Big Dipper...they could see Ursa Major, the Great Bear...dipped low in the western sky, the leaves of the trees would turn red. Fall was here.

The story goes that three hunters were trailing the bear. The hunters were the three stars that we see as the handle of the Big Dipper. One of the hunters had shot the bear in the side, but the wound wasn't serious enough to stop the bear. The middle hunter carried a pot on his shoulder to cook the bear meat in, but the hunters never got close enough to kill the bear. He went crashing through the forests of the night, always managing to keep the same distance ahead of the three hunters. At the end of summer, the bear and the hunters grew tired, and they dipped lower and lower toward the horizon. When the bear got very close to the horizon, close enough for blood to drip from the wound in his side onto the trees, the people noticed that the leaves turned red. It was time to harvest and finish preparation for winter.

In ancient Greece, the people who lived there believed in a number of different gods that looked over them and, according to the stories, had regular lives with ups and downs, loves and fights, kids and occasionally, battles. The chief god was Zeus.

The story about the Big Dipper goes something like this: Zeus fell in love with Callisto, daughter of Lycaon and by her had a son, Arcas. In order to spare Callisto from the wrath of Hera (this was Zeus' wife - even the gods weren't perfect), Zeus changed her into a bear to hide her identity.

The Big Dipper

I had no idea how much time NCAA basketball would take to watch over the last four days - and how exhausting it was! But as I understand, the weather did not cooperate much for looking at the night sky over Bend.

Tonight promises to be different. Although I said we talk about Mars next, a constellation in tonight's sky might be worth catching. The Big Dipper is actually part of a larger constellation called Ursa Major. Sailors used the stars to guide their ships while ancient people - before the internet, before television, before written words, used these groups of stars in the night sky to tell stories.

The constellation Ursa Major contains the group of stars commonly called the Big Dipper. The handle of the Dipper is the Great Bear's tail and the Dipper's cup is the Bear's flank. The Big Dipper is not a constellation itself, but an asterism, which is a distinctive group of stars. Another famous asterism is the Little Dipper in the constellation Ursa Minor. More on Minor later on.

Can you find the North Star or Polaris?

First, you have to find the Big Dipper in the Northeast.

A Planetary Flyby

The morning sky this month is spectacular. And I know someone who is up that time on his way to school. And with the switch of daylight savings, it is still dark enough to see these events.

I've talked about Saturn (which you can still see in the evening sky looking east) and Venus (which you can still see looking west at about the same time). I mentioned that we probably wouldn't be here on earth if it were not for Jupiter blocking a lot of space junk that might get hurled into our blue planet.

And if you look southeast in the morning, you can see Jupiter. But here is something else exciting in that early sky: Mercury and Mars.

Mercury is in the southeast when Jupiter is at its brightest. Look just over the horizon and when you find Jupiter, look to the lower left and you should be able to see Mercury. At 51 million miles from Earth, it is the closest planet to the sun.

Even more fun, it is about to be orbited again by Messenger. On its 4.9 billion-mile journey to becoming the first spacecraft to orbit the planet Mercury, MESSENGER has flown by Earth once, Venus twice, and Mercury twice. Still to come is one more flyby of Mercury in late September 2009.

And even though Mercury is really close to the sun, it actually has water ice at the bottom of deep craters where the sun never shines. Mercury looks a lot like the moon but it has no moons of its own. It does have an atmosphere but because it is so close to the sun, the solar winds whip it out into space.

It would be hard to figure out what clothes to bring if you ever went there. The temperatures range from 450 degrees Celsius (840 degrees F) during the day as low as -170 degrees C (-275 degrees F) at night! Hotter than Venus and then colder than cold.

You have to look really close because the sun can be just bright enough to make it hard to see.

Tomorrow: Mars

Is Someone Looking at Us?

While the night sky over Bend is cloudy and there still isn't much to see, maybe we should talk for a minute about us.

There was time when we thought the Earth was the center of the universe. Nicolaus Copernicus's 1543 book, "On the Revolutions of the Heavenly Spheres", moved Earth from being the center of the Universe to just another planet orbiting the Sun. He was not popular because of this and told only a few people about what he thought. In fact, he was so sure that this idea was not going to get him any fans he decided to mention it - after he died.

If you fast forward to now, we know that we might not even be alone. Not only is the earth not the center of our solar system. but it isn't even near the center of our own galaxy, the Milky Way. We now know that the universe doesn't even have a center!

Science has determined that something like earth may exist in other places in the universe.

Here's why. We are located in a solar system and that system is in a galaxy. In order for a planet like ours to exist somewhere else, folks believe that we would need to be in a galactic habitable zone or GHZ. The Hubble Telescope has looked at 69 different galaxies within 30 million light years of where you are standing and do you know what they found? No galaxy is the same as another.

Looking even deeper into these galaxies (which can be made up of millions of solar systems (planets circling a star like our sun) we now know that planets have to be just the right distance from their sun to be worth living on.

Not only are we looking for water - which we think is the only way life could exist - but we are also looking for a moon around those planets. The moon pulls and tugs a planet and if we didn't have ours, we would be tilting in all sorts of directions. Sometimes the north pole would be tilted towards the sun; other times it would not. This would cause the temperature to change a lot. It might be hot in the summer and cold in the winter but without a steady tilt (the kind the moon gives us has been steady for billions of years), we wouldn't be able to survive the harshness.

Having a good position around the sun and a moon to make earth worth living on, it is possible that the sky might have as many as one million earths. Science figures that this is only about 10% (one in ten) of all of the planets in the universe. Once again, this is only a guess but a pretty good one.


Believe it or not, if it wasn't for earthquakes, we probably wouldn't be here. If it wasn't for Jupiter blocking large objects from banging into us, we wouldn't be here.

So the chances that someone may be looking for us the way we are looking for them is pretty good. As you look to the sky, somewhere, someone just like you might be looking back. Be sure to wave!

Don't say goodbye to Venus

It has been an incredible year to see the closet planet to the earth. Venus has been the showstopper in the evening sky all winter. But believe me, you wouldn't want to live there.

For one, it is hot. The nasty atmosphere is mostly carbon dioxide and it traps all of the heat from the sun (it is only 67 million miles away). While there are super-sized, hurricane force winds in the upper part of the sky on Venus, the surface has none. And if it did, because of how thick it is, a small breeze would knock you on your butt.

Of course you would have to survive the pressure first. Imagine being the guy on the bottom of a big pile-on. Hard to breath, weight crushing you and you can't move. That is what a vacation on Venus would be like. And the darned planet spins in the wrong direction with the sun rising in west, not the east.

The planet not only spins backwards, it takes 243 days for one day on Venus. If you were reading this on Venus, a couple of Earth days might have already passed. In fact, on Venus, one school day would last almost four months.

So it is much more fun to watch than to visit. Every day in March, Venus drops closer to the western horizon after sunset. But as it disappears from the evening sky, it enters the morning sky. It dims a bit toward the end of the month but brightens again as it assumes the title of Morning Star in April.

Looking Through the Clouds

I see the weather in Bend hasn't improved much since I last posted. Clouds can be a real problem when trying to look at the night sky. Even on a good day, the city of Bend makes it tough to see a lot of what is happening in your area.

The lights from the city are called ambient (am be ent). The sky, no matter how dark is not as dark as it could be because of these lights from buildings and street lamps. Did you know, that no matter where you go in the lower 48 states of America you can only see about two thousand stars. The darkest place (Death Valley) is impacted by the lights of a city hundreds of miles away (Las Vegas).

So when the clouds are out, they act as a reflector for those lights making seeing the sky even harder. Not impossible, just more difficult.

If you have a moment check this video out on what to expect when those clouds clear enough to get another look at what is happening above your head.

Saturn's March show

Note from Papa to Andre: This is a way to give you all of the information any young skywatcher should need to understand what he sees in the night sky. I'll include a weather forecast with each post, some directions and some background on the subject.

Last week, I sent your Mom an email about looking for Saturn in the early evening sky to the east of you. In it I told you about the first astronomer to see the rings around the planet. Only his telescope was so primitive - he made it himself even grinding the glass lens - that his view of the distant planet (746 million miles from earth) was rather crude.

It was so crude that Galileo assumed they were jug handles. In fact, this picture was taken using a replica of what Galileo saw. We now know that they are rings. It was two years before he was able to find the planet again and he was astonished that the rings had disappeared. Do you know why?

The next time Galileo was able to see the planet the tilt, or angle the planet was pointed at the astronomer had changed and the rings where nothing more than a straight line across the planet.

It is too bad that the weather in Bend will not be good for looking at this event but you might be able to catch it in the morning on the western horizon - perhaps underneath the clouds or in between snow showers.

Here is some other stuff about Saturn that you may not have known. It has sixty moons and is really cold. Try and imagine 170 degrees below zero cold! It also takes twenty nine and half years to get around the sun. If you were born on Saturn, you would only be a couple of months old!

Next up: some stuff you can look forward to when the clouds go away.