EXPLOSION IN SPACE — THE NOVA IN SAGITTARIUS by William J. Bechaver

This week, I was going to write about the asteroid belt, and the diversity of the many objects and bodies found in that mysterious region of space between Mars and Jupiter. But the asteroid belt will always be there. Suddenly, we were presented with an opportunity to view something so fleeting, and so rare.

Instead, we will focus our attention far beyond the reaches of our solar system this week, to a distant pair of stars that have always been so remote, and so small, that they have never been visible from earth. Until now.

They are in a region of the sky in the constellation Sagittarius, just below the lid of the teapot. “The Teapot” is an asterism within the constellation of Sagittarius. An asterism is a grouping of stars that resemble an object, or form an image of something that is familiar to us. The most famous asterism is The Big Dipper. Most think The Big Dipper is a constellation, but that supposition is incorrect. It is an asterism that lies within the constellation of The Great Bear, up near the north star. The handle of The Dipper is the tail of The Bear. Likewise, The Teapot is the body and outstretched arm of Sagittarius.

Right now, the distant stars below the lid are increasing in brightness, becoming visible from earth for the first time. The increase in brightness is due to a massive thermonuclear explosion on the surface of one of the stars. The resulting explosion is called a nova.

The nova is now visible with the naked eye, and scientists think it will continue to increase in brightness for some time. A nova is produced in binary star systems. A binary star is a pair of stars that revolve around each other. The smaller, dwarf star, begins to strip gases away from the larger companion star. These gases build up on the hot surface of the smaller star, until the buildup results in a nuclear explosion, which casts debris off into space, and increases the brightness of the star, until that star, previously so small and so distant, suddenly becomes visible from earth for the first time. The nova was only discovered last week, as the light from the explosion became apparent from earth. At that time, the explosion was expanding from the star at a rate of 6.2 million miles an hour! Before long, the explosion became visible to the naked eye.

image

Sagittarius lies within a region of space with which we have all become familiar as of late. It is just to the left, or east, of Scorpius. Three weeks ago, we focused on Saturn, which is in the upper part of Scorpius. Go outside this week, just after 5:00 a.m. Look in the southern sky for Saturn. Just below the bright planet is the brightest star in the arc of Scorpius, Antares. A little lower, and to the east, is The Teapot. It takes only a little imagination to pick out the form among the dimmer stars. It sits upright on the south-east horizon, The Milky Way forming the steam from the spout. Within the body of The Teapot, just below the lid, you will see a star, fainter than the others that form the pot. But if you watch it, over the course of days, it will increase in brightness. Then later, as the explosion dissipates in space, it will become red as the light from the explosion is disbursed. It is a star that has always been there, but has never been seen from earth, and in just a few weeks, it will once again fade into oblivion, as the distant sun fades back to its former magnitude.

Though scientists have not confirmed the distance to the star, it is thought to be at least thousands of light years away. So, the explosion you are witnessing today, as you look at the nova in The Teapot, actually occurred thousands of years ago. So distant are the stars we’re talking about, that it has taken the light from the explosion all those millennia to cross the intervening space, until we are finally seeing the result of the explosion now. Chances are, it exploded long before the time of Moses and The Pharaohs Of Egypt. In ancient times, a nova was seen as a terrible omen, a predictor and precursor of doom, as it was thought a new star was coming into the sky. We now know it is simply the brightening of a distant star that has been there all along.

Venus is ever growing nearer as it catches us in its orbit. Weekly, we are keeping track of its progress, as the distance to our sister planet decreases. Last week, it was 119.04 million miles distant. This week, the distance has decreased to 115.32 million miles. It has grown nearer in the past week by nearly 4 million miles!

Thanks for your interest in astronomy and our featured articles! If you have any article requests or questions, contact Spanish Peaks Amateur Cosmos Enthusiasts [SPACE] at spacescape@rocketmail.com for inquiries about scientific information.

William J. Bechaver is the Director of SPACE – Spanish Peaks Amateur Cosmos Enthusiasts [SPACE], the local Astronomical Society in Southern Colorado.

THE CHANGING PHASES OF VENUS by William J. Bechaver

There has been a lot of interest regarding the planet Venus, of late. Mostly because it is so prominent, and amazingly bright in our evening skies right now, it garners the attention of casual viewers and stargazers. How could it not. Weekly, the apparent distance between the planet and the setting sun is increasing, putting the glowing gem higher into the evening sky. From our point of view, it will continue to climb higher until early June, as it swings around in its orbit. Then, from that point, it will begin sinking lower in the sky, as it approaches Earth in its orbit.

Venus is nearer the sun than are we, and therefore travels in its orbit at a greater speed. Furthermore, it being nearer, its orbit is a shorter distance than is ours. Right now, the two planets are in a race around the sun. Venus is in the rear, but gaining quickly. In June, it will make the final turn, and come down the homestretch. That’s when it will appear furthest from the sun. It has been slowly climbing in the evening sky for a couple of months already, and will not reach maximum elevation until June. But from that point, as it approaches, and eventually overtakes us, in its orbit, it will descend more quickly, rushing toward us. It will makes its closest approach in mid-August, when it will pass directly between the Sun and Earth.

image

Currently, Venus is a fair distance from us. That’s what makes its brilliant appearance in the evening sky so impressive. Right now, it is 119 million miles away from us, much further away than is the sun. It will continue to increase in brightness slightly, until June. But from then on, the magnitude of Venus will not continue to increase, even though it is coming much nearer to us. Venus, being nearer the sun, goes through phases, much like our moon does. Right now, we are seeing the sunlight reflected off more than half of the sunlit side. When it makes its swing around the far side of its orbit, we will see the sun reflected off only half of the planet. We will be seeing equal parts of the day-side and night-side of the planet. But as it comes closer to us, the further side of Venus is facing the sun, so we will see less and less of the sunlit side. When it is at its closest approach, it will appear much larger in a telescope, but we will see much less of the bright side of the planet. It will appear as a tiny crescent, larger, yet not as bright, because we are then looking mostly at the dark, night-side of the planet. That is why Venus is not always at its brightest when it is closest. In fact, when it makes its closest approach, we can not see it at all. We are then looking only at the dark side of the planet, as the far side is lit by the sun. Further, it is completely lost in the glare from the sun. So in August, when it is only 27 million miles away, our closest approach this year, we won’t be able to see Venus at all. From now until June it will make its greatest appearance, growing slightly brighter, and ever climbing into darker skies, away from the setting sun. By June, it will remain in the sky a full three and a half hours after sunset. It is truly a glorious sight to behold.

Since we had a nice grouping last month, let us see where the players in our conjunction lie a month later. On the evening of Saturday 21 March, go out after sunset. The moon will appear very close to the fading planet Mars. As Venus has continued to climb, Mars has appeared to sink closer to the sun. Mars is further from the sun than are we, so just as Venus is catching us in its orbit, and climbing higher into the sky, the Earth is outrunning Mars around the sun, leaving it far behind, on the far side of the sun. To witness just how far Mars has sunk, and Venus has climbed, the following evening, Sunday 22 March, the moon will be near brilliant Venus, for another impressive pairing, both brilliant, while leaving the diminished Mars far below, and far behind.

Venus is ever growing nearer as it catches us in its orbit. Weekly, we will keep track of its progress, as the distance to our sister planet decreases. Last week, it was at 123,760,000 miles away from us. This week, the distance is just 119,040,000. In only a week, it has gained on us by nearly 5 million miles!

Thanks for your interest in astronomy and our featured articles! If you have any article requests or questions, contact Spanish Peaks Amateur Cosmos Enthusiasts [SPACE] at spacescape@rocketmail.com for inquiries about scientific information.

William J. Bechaver is the Director of SPACE – Spanish Peaks Amateur Cosmos Enthusiasts [SPACE].

PLANETS – FROM GIANTS TO DWARVES — EXPLORING CERES by William J. Bechaver

Many of us think of astronomy as an observational science. We go outside and look up at the full moon, or even a “super moon”, or find Orion’s belt, or The Big Dipper, or thanks to the World Journal Astronomer, find Saturn and wonder why it’s so bright when it’s so distant. But in actuality, what we see is only a very small part of astronomy, and sometimes the most interesting thing is what we can’t see.

But first, let us continue our lunar tour through the night sky, as we follow the moon as it encounters the objects in our solar system. We are nearing the end of our tour this week, and none of it will be as spectacular as the first weeks. The moon has actually passed the brighter of the planets now, having a beautiful encounter with Venus and Mars, then a near-grouping with Jupiter, and another with Saturn. Now what we’re left with are minor and distant planets that are difficult to see, and almost impossible to find. Furthermore, we’re left with encounters in the early morning hours, when getting up early for something that’s not immediately apparent makes planetary astronomy seem a little arduous, and that’s why we’ll use the moon as our guide, and learn about some of the things we can’t see.

Let us begin with the Ides Of March. Fortunately, the sun rises later this week, thanks to Daylight Saving Time, so many of us will be up already. On Sunday 15 March, go outside about an hour before sunrise, or at about six o’clock. The moon will be nearly two days past its last quarter phase. When you find the moon, to its lower right, is the planet Pluto. Pluto is the most distant visible object in the solar system, but you will need binoculars to spot it. And even so, it is so small and rocky, it is unremarkable in every way at this distance. It doesn’t give us the blue or green hue that we get from the distant gas giants Uranus and Neptune. It will look about as the moons of Jupiter appear in a telescope. Pluto was discovered only 85 years ago, and only due to its slow motion against the background of stars, not by any other discernable planetary trait. So that is our encounter with Pluto.

The next morning, if you go out and find the moon, it will be diminishing into a finer crescent. To the right of the moon, and just as unremarkable as Pluto, is the planet Ceres. If you’ve never heard of it until this moment, you are not alone. Ceres, like Pluto, is a minor planet in our solar system, but much nearer than is Pluto. It lies between the orbits of Mars and Jupiter, in the area we were always taught is The Asteroid Belt. Ceres is the largest object in The Asteroid Belt, and the only dwarf planet in the inner solar system. It was the first “asteroid” discovered way back in 1801, so we’ve known about it for a lot longer than we’ve known about Pluto, yet it has never gotten the respect and recognition it deserves, until now. It is much smaller than Pluto, only a little more than a third as big. And Pluto is only about two-thirds the size of Earth’s moon. So we’re talking about some very small planets, at very great distances. But now, we’re learning more about Ceres than ever before. Just last Friday, the Dawn Spacecraft entered into orbit around Ceres to photograph it, and send back scientific data about the planet in more detail than ever before. This is the first time we’ve ever encountered it so closely.

We were always taught that there are nine planets in the solar system. This all changed back in 2006, when the designation of more minor planets was changed. They termed these larger minor planets Dwarf Planets. All of a sudden, Pluto was demoted, and we were back to having eight planets in the solar system, after eighty years of learning otherwise. But it still remains, after all the debate, that Pluto is a planet. As Professor Fran Bagenal points out, Pluto may now be considered a Dwarf Planet, but dwarf people are still people, so Pluto is still a planet. But considering that, the population of Dwarf Planets has increased. Right now, the scientific community recognizes five dwarf planets in our solar system, including Pluto and Ceres. So, technically, the population of our solar system has grown, not shrunk, from nine planets, to thirteen, including the dwarves. So, there are four giant planets, and five dwarf planets, and we average rocky planets here in the inner solar system, are all of a sudden outsized and outnumbered.

Eris is the most massive of the dwarf planets. It is about the size of Pluto, but is far more distant. It is nearly three times more distant from the sun than is Pluto. It takes the light of the sun 5 hours to reach Pluto and 13 hours 30 minutes to reach Eris. Since it has taken us 9 years to reach Pluto using our latest and fastest technology in space travel, it would take us nearly 25 years to reach Eris. If we had a probe ready to launch tomorrow, it would not arrive at Eris until the year 2040. We will explorer other dwarf planets, and more distant objects in the near future, as we learn more about Ceres with the arrival of Dawn now, and more about Pluto this summer, with the arrival of New Horizons. We’ll delve into them in more detail then.

But, let us not forget to finish up our tour of the major planets in our solar system. If you go out on the early morning of Wednesday 18 March, and look toward the east, you will be able to spot the tiny crescent of the moon. Just below it, about half way to the horizon, you may be able to spot the faint speck of light that is Mercury. Though much nearer to us, it will be as difficult to spot as Pluto. We very recently watched it in the evening sky near Venus, but since early January, it has swung all the way around the sun, and is in the morning sky. Right next to Mercury, up to the left, is the planet Neptune. Once again, you won’t be able to see it with a naked eye, and in the morning twilight, it will be really hard to spot. The following morning, the moon will be even nearer the two planets. It would be a conjunction to rival last month’s gathering of Venus, Mars, and the Moon. But with the moon being a fine crescent, less than a day away from becoming new, and Mercury so faint, and Neptune invisible without a telescope at that stage, it will be impossible to view. You will be doing well if you can spot the moon at that phase. And, as the moon joins the sun to begin its next cycle, that concludes our month-long tour through the solar system objects, gracefully led by the moon. Like all tours, that has just opened the door to many objects we will have to return to, and explorer in greater detail.

William J. Bechaver is the Director of SPACE – Spanish Peaks Amateur Cosmos Enthusiasts [SPACE].

image
Ceres – taken last week by the Dawn Spacecraft, shows two mysterious bright objects in one of the craters on the dwarf planet. It is believed to most likely be ice.

THE RINGS OF SATURN AND SAVING DAYLIGHT by William J. Bechaver

This week, let us continue our voyage across the heavens with the moon. In the past couple of weeks, we’ve visited Venus and Mars, Uranus, and this past week, Jupiter. This week, the moon will have a pretty close encounter with Saturn. During the late night hours of Wednesday 11 March, go outside and look east for the rising moon. The waning gibbous moon, just shy of the third-quarter phase, will actually rise just after midnight, so technically on the morning of March 12. Just two degrees to the left of the moon, the distinct glow of Saturn will be easily discernable. Since we visited it late last year, Saturn has continued to rise from the early morning sun, higher into the dark night sky. It has also continued to increase in brightness. In a couple of months, Saturn will be at its brightest for us, and be making an impressive show as we make our closest approach for the year, and pass the giant planet in its orbit.
image

There are two reasons Saturn is increasing in brightness. Saturn is one of those amazing objects in our solar system that can appear brighter, even when it’s further away. That is due to the fact that the planet Saturn is surrounded by an intricate system of dense rings, as we all know. But the position of those rings changes from our point of view, as the planet Saturn goes through a cycle of seasons, much as our own. Sometimes, we view those rings edge-on, more like they appear in Image 2, provided by The Hubble Space Telescope. It is at those times, that Saturn can appear less bright in the sky, even if it is at its closest approach to our planet. Right now, the reverse is true. Even though Saturn is a good distance removed from our planet, the rings appear like in Image 1. The surface of the rings, therefore, reflect more light to earth, which causes it to appear very brilliant in the night sky. As we approach Saturn for the next couple of months, the rings will continue to be tilted toward our field of view, making it one of the brightest views we will have of the planet. Saturn is actually a huge gas giant planet, second in size in the solar system only to mighty Jupiter. It is much more distant than Jupiter in its orbit, but when you take its ring system into account, it is almost as large, from ring tip to ring tip, as Jupiter’s diameter in a telescope. In actuality, it is much larger in diameter than is Jupiter, when you measure the diameter of the ring system. The rings of Saturn are more than twice the size of Jupiter, and are mostly composed of water ice, making them extremely reflective, like snow in space. So extensive is the ring system of Saturn, that it would take 22 planet Earths to span from one end of Saturn’s rings to the other! We are much nearer Jupiter right now, but as our distance from Jupiter increases, and we begin to catch up with Saturn in its orbit, Saturn will brighten substantially in the next couple of months, as Jupiter will dim. We are all on the same side of the solar system right now, so the change won’t be very drastic, but come summer time, Saturn will be an impressive sight, providing nice warm-weather views in a telescope.

Here’s an observation of note. On Saturday 7 March, the sun will set at precisely 6 o’clock for us. The following night, 8 March, it will set an entire hour later, not until 7 o’clock. This is no natural phenomena, but is caused by man, as Daylight Savings Time begins on Saturday night, so don’t forget to spring your clocks forward. It will remain dark outside an hour later in the morning, possibly making it more convenient for some early morning hour viewing that we have in store for next week.

William J. Bechaver is the Director of SPACE – Spanish Peaks Amateur Cosmos Enthusiasts [SPACE].

End Of Posting

Test

Thanks for your interest in astronomy and our featured articles! If you have any article requests or questions, contact Spanish Peaks Amateur Cosmos Enthusiasts [SPACE] at spacescape@rocketmail.com for inquiries about scientific information, or follow us on Twitter @ColoSpacEScapE for current updates or additional viewing opportunities.

William J. Bechaver is the Director of SPACE – Spanish Peaks Amateur Cosmos Enthusiasts, the premier Astronomical Society in Southern Colorado.

Test

This will be fun? I’m thinking.