Tammy Plotner, Author at Universe Today

June 8, 2009December 24, 2015 by Tammy Plotner

IYA Live Telescope Library – Messier 7

Were you tuned in to Galactic TV last week? If not, you missed an opportunity to visit with Messier object. Although the Moon was shining bright, mighty M7 could still cut through and send us a starry view! If you didn’t get a chance to see it – no worries. We did a video recording for you and saved it. Just step inside the library to watch….

(The following information is a direct quote from Wikipedia.)

OBJECT INFORMATION: M 7 – SCORPIUS

Messier 7 or M7, also designated NGC 6475 and sometimes known as known as the Ptolemy Cluster, is an open cluster of stars in the constellation of Scorpius.

The cluster is easily detectable with the naked eye, close to the “stinger” of Scorpius. It has been known since antiquity; it was first recorded by the 1st century astronomer Ptolemy, who described it as a nebula in 130 AD. Giovanni Batista Hodierna observed it before 1654 and counted 30 stars in it. Charles Messier catalogued the cluster in 1764 and subsequently included it in his list of comet-like objects as ‘M7’.

Telescopic observations of the cluster reveal about 80 stars within a field of view of 1.3° across. At the cluster’s estimated distance of 800-1000 light years this corresponds to an actual diameter of 18-25 light years. The age of the cluster is around 220 million years while the brightest star is of magnitude 5.6.

As always, you can visit the remote telescope by clicking on the IYA “LIVE Remote Cam” Logo to your right. We’ll be broadcasting whenever skies are clear and dark in Central Victoria! Enjoy…

Many thanks to all the contributors at Wikipedia for all that you do!

June 5, 2009December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast: June 5-7, 2009

Greetings, fellow SkyWatchers! Are you ready for another great weekend of observing? If you’re thinking that it’s going to be boring because there’s Moon, then think again. If you were paying attention, you’d have noticed that Venus and Mars rose together this morning only about five degrees apart. Need more reasons to get out? Try 13 of them as you challenge yourself to see how many craterlets you can resolve in the mighty Clavius. Stars more to your liking? Then have a look at the Theta Virginis system or beautiful red Omega. Celebrate the Strawberry Moon, locate R Hydrae or just be on hand for an occultation event… It’s all part of the weekend scene! Grab your telescopes or binoculars and I’ll see you in the backyard.

Friday, June 5, 2009 – If you were up early this morning, did you see Venus and Mars no more than 30 minutes before dawn? The pair was very low – only about 20 degrees above the horizon -and about 5 degrees apart.

Now, let’s take a look at John Couch Adams, a discoverer of Neptune who was born on this date in 1819. Said he:

‘‘. . .the beginning of this week of investigating, as soon as possible after taking my degree, the irregularities in the motion of Uranus. . .in order to find out whether they may be attributed to the action of an undiscovered planet beyond it.’’

But that’s not all Adams contributed! He was the first to associate the Leonid meteor shower with the orbital path of a comet, and he also observed the Moon.

As we begin observing Selene this evening, let’s have a look at awesome crater Clavius. As a huge mountain-walled plain, Clavius will appear near the terminator tonight in the lunar Southern Hemisphere, rivaled only in sheer size by similarly structured Deslandres and Baily. Rising 1,646 meters above the surface, the interior wall slopes gently downward for a distance of almost 24 kilometers and spans 225 kilometers. Its crater-strewn walls are over 56 kilometers thick! Clavius is punctuated by many pockmarks and craters; the largest on the southeast wall is named Rutherford. Its twin, Porter, lies to the northeast. Long noted as a test of optics, Clavius crater can offer up to 13 such small craters on a steady night at high power. How many can you see?

If you want to continue tests of resolution, why not visit nearby Theta Virginis (RA 13 09 56 Dec -05 32 20)? It might be close to the Moon, but it’s 415 light-years away from Earth! The primary star is a white A-type subgiant, but it’s also a spectroscopic binary comprising two companions that orbit each other about every 14 years. In turn, this pair is orbited by a 9th magnitude F-type star that is a close 7.1’’ away from the primary. Look for the fourth member of the Theta Virginis system, well away at 70’’ but shining at a feeble magnitude 10.4.

Saturday, June 6, 2009 – Today is all about lunar history! We begin with the 1932 birth on this date of David Scott, the seventh person to walk on the Moon and the first to ride the Lunar Rover on the surface during the Apollo 15 mission. Sharing his birth date, but almost 500 years earlier, was the astronomer Regiomontanus (1436). Regiomontanus made observations of a comet, which were accurate enough to associate it with Comet Halley 210 years later, and his interest in the motion of the Moon led him to make the important observation that lunar distances could be used to determine longitude at sea! Let’s head to the Moon. . .

Although at first glance tonight crater Copernicus will try to steal the scene, head further south to capture another Lunar Club Challenge – Bullialdus. Even binoculars can make out this crater with ease near the center of Mare Nubium. If you’re scoping, power up – this one is fun! Very similar to Copernicus, note Bullialdus’ thick, terraced walls and central peak. If you examine the area around it carefully, you can note it is a much newer crater than shallow Lubiniezsky to its north and almost non-existent Kies to the south. On Bullialdus’ southern flank, it’s easy to make out itsA and B craters, as well as the interesting little Koenig to the southwest. Although it will be a bit overlit, if you head to the southeast shore of Mare Humorum, you can spot crater Regiomontanus as well. It’s just south of Purbach.

Now let’s starhop four finger-widths northwest of Beta Virginis for another unusual star – Omega (RA 11 38 27 Dec +08 08 03). Classed as an M-type red giant, this 480 light-year-distant beauty is also an irregular variable that fluxes by about half a magnitude. Although you won’t notice much change in this 5th magnitude star, it has a very pretty red coloration and is worth the time to view.

Sunday, June 7, 2009 – Today we celebrate the birth of Bernard Burke, co-discoverer of radio waves emitted from Jupiter. Listening to Jupiter’s radio signals is a wonderful hobby that can be practiced by anyone with enough room to set up a dipole antenna. If you’d like more information—or want to hear a recording of Jupiter yourself—visit Radio JOVE on the web! Tonight is Full Strawberry Moon, a name used by every Algonquin tribe in North America because the short season for harvesting the tasty red fruit comes each year during the month of June!

Tonight let’s have a look at a tasty red star – R Hydrae (RA 13 29 42 Dec -23 16 52) located a fist-width south of Spica. R Hydrae was the third long-term variable star discovered and was credited to Maraldi in 1704. Although Hevelius observed it 42 years earlier, it wasn’t recognized as variable because its changes happen over more than a year. At maximum, R reaches near 4th magnitude, but drops well below naked-eye perception to magnitude 10. During Maraldi’s and Hevelius’s time, this incredible star took over 500 days to cycle, but it has speeded up to around 390 days in the present century.

Why such a wide range? Scientists aren’t really sure. R Hydrae is a pulsing M-type giant whose evolution may be progressing more rapidly than expected due to changes in structure. What we do know is that it’s around 325 light-years away and approaching us at 10 kilometers per second! To the telescope, R will have a pronounced red coloration, which deepens near minimum. Nearby is 12th magnitude visual companion star Ho 381, which was first measured for angle position and distance in 1891. Since then, no changes in separation have been noted, leading us to believe the pair may be a true binary.

Now watch as the Moon devours a red star! Brilliant Antares will be less than a half degree away from the limb for most observers and will be occulted for some lucky others! Be sure to check the IOTA website for exact times and locations and enjoy!

Until next week? Ask for the Moon, but keep on reach for the stars!

This week’s awesome images are (in order of appearance): Clavius (credit—Wes Higgins), Theta Virginis (credit—Palomar Observatory, courtesy of Caltech), Bullialdus (credit—Wes Higgins), Omega Virginis (credit—Palomar Observatory, courtesy of Caltech), Nearside of the Moon as imaged by Apollo 11 (credit—NASA) and R Hydrae (credit—Palomar Observatory, courtesy of Caltech). We thank you so much!

June 2, 2009December 24, 2015 by Tammy Plotner

Magic Bubble – NGC 7635 by JP Metsavainio

[/caption]

Away in the constellation of Cassiopeia some 7,100 light-years from Earth, a star 40 times more massive than our Sun is blowing a giant bubble of its own material into space. Inside its magic blue sphere, the gigantic star burns at blue flame intensity – rendering a 6 light year wide envelope of hot gas around it that’s expanding outward at a speed of 4 million miles per hour. Are you ready to open wide and step inside? Then welcome to a little dimensional magic….

As always, whenever we present a dimensional visualization it is done in two fashions. The first is called “Parallel Vision” and it is much like a magic eye puzzle. When you open the full size image and your eyes are the correct distance from the screen, the images will seem to merge and create a 3D effect. However, for some folks, this doesn’t work well – so Jukka has also created the “Cross Version”, where you simply cross your eyes and the images will merge, creating a central image which appears 3D. For some folks, this won’t work either… But I hope it does for you!

As the central star in NGC 7635 sheds its material, we can see it isn’t even and its appearance varies with the thickness of the surrounding gases. What appears to be cloud-like structures are very thick and illuminated by the star’s intense ultraviolet light. Believe it or not, it is here where the stellar “winds” blow the fastest and it won’t be long until these areas quickly erode. However, there is one feature that stands out more than any other – the “bubble-within-a-bubble”. What is it? It may be two distinct winds… Two distinct streamers of material colliding together.

“The bubble in NGC 7635 is the result of a fast stellar wind expanding into the interior of the larger H II region. However, the central star BD +60 2522 is appreciably offset (by about 1′) from the center of the bubble in the direction of the wall of the dense molecular cloud that defines this blister H II region.” says B.D. Moore (et al), “This offset is the result of evolution of the wind bubble into the density and pressure gradient established by the photoevaporative flow away from the cavity wall. The physical conditions around the bubble vary according to the medium into which the bubble is expanding. Away from the cavity wall the bubble is expanding into the low density interior of the H II region. Toward the wall, in the region of our images, the wind termination shock is very near the ionization front. The resulting physical structure, in which the photoevaporative flow away from the cloud wall is confined by the ram pressure of the wind.”

But, are we not seeing the proverbial forest because we’re too busy looking at the trees? “BD +60 is the ionizing star of NGC 7635, the so-called “Bubble Nebula”. NGC 7635 lies at the edge of a low-density clumpy molecular cloud and the nebula can be interpreted as a wind-blown bubble created by the interaction of the stellar wind of BD +60 with the ambient interstellar medium. While many investigations have focused on the nebula, little attention has been paid to the star itself.” says G. Rauw (et al), “Considerable progress in our understanding of the stellar winds of early-type stars has been achieved through extensive monitoring of their spectroscopic variability and the discovery that some of the cyclical variations could be related to a rotational modulation of the stellar wind. Since rotation is believed to shape the winds of Oef stars, these objects appear a priori as good candidates to search for a rotational wind modulation.”

Throughout their long term observing campaign, the group found strong profile variability on time scales of 2–3 days, variability on time scales of a few hours that might be related to non-radial pulsations, and even tentatively propose that the beating of several non-radial pulsation modes triggers transient large-scale density perturbations in a confined stellar wind that produce the 2–3 day time scale variability. “While this scenario could easily account for the lack of a single stable period (through the effect of the propagation velocity of the perturbation and the interplay of various clocks: pulsations, rotation…), it seems more difficult to explain the changing pattern of the TVS. For instance, if a density wave moves around the star, why would it not affect the absorption and the emission components in a similar manner?” says Rauw, “One possibility could be that the density perturbation affects the absorption column only as long as it remains close to the stellar surface whilst the impact on the emission lines would be larger when the perturbation has moved outwards, but this is admittedly still rather speculative.”

Just how common is it for a huge star to form a bubble around itself? “Massive stars evolve across the HR diagram, losing mass along the way and forming a variety of ring nebulae. During the main sequence stage, the fast stellar wind sweeps up the ambient interstellar medium to form an interstellar bubble. After a massive star evolves into a red giant or a luminous blue variable, it loses mass copiously to form a circumstellar nebula. As it evolves further into a WR star, the fast WR wind sweeps up the previous mass loss and forms a circumstellar bubble. Observations of ring nebulae around massive stars not only are fascinating, but also are useful in providing templates to diagnose the progenitors of supernovae from their circumstellar nebulae.” says You-Hua Chu of the University of Illinois Astronomy Department, “The fast stellar wind of a main sequence O star sweeps up the ambient interstellar medium (ISM) to form an interstellar bubble, which consists of a dense shell of interstellar material. Intuitively, we would expect around most O stars an interstellar bubble similar to the Bubble Nebula (NGC 7635) to be visible; however, hardly any O stars in HII regions have ring nebulae, suggesting that these interstellar bubbles are rare.”

Like a child chewing gum, the bubble will continue to expand. And what comes after the bubble? Why, the “bang” of course. And when it comes to a star going bang, than can only mean a supernova. “By pursuing the calculation through the various stages of massive star evolution, using a realistic mass loss history as input, we simulate the creation and evolution of a wind-blown bubble around the star up to the time of the supernova explosion.” says A. J. van Marle (et al), “The outflowing matter encounters an inner shock, where its velocity is reduced to nearly zero. The kinetic energy of the wind becomes thermal energy. This interaction creates a “hot bubble” of nearly stationary, hot gas. The thermal pressure of the hot bubble drives a shell into the surrounding interstellar medium. Here it is assumed, that the pressure driven shell will be restrained only by the ram pressure created by its own velocity and the density of the surrounding medium. This assumption is correct if we consider the surrounding medium to be cold. However, if we take photo-ionization into account the situation becomes rather more complicated. First of all, the photoionized gas will have a much higher pressure than the cold ISM. Therefore, the HII region will expand, driving a shell into the ISM. Second, the hot-bubble created by the stellar wind will now expand into a hot HII region, which means that the thermal pressure restraining the shell, will no longer be negligible compared to the ram pressure. A wind-blown bubble expanding into a compact HII region can be observed in NGC 7635.”

So how do we know when the final moments have come? “As the star ages, it becomes a red supergiant with a dense and slow wind. The number of ionizing photons drops. Therefore, the HII region disappears. Owing to the low density, recombination will take a long time, but radiative cooling will cause a decrease in thermal pressure. The hot wind-bubble, which keeps its high pressure, expands into the surrounding gas, creating a new shell. A third shell appears close to the star, as the drop in ram pressure from the RSG wind causes the wind bubble to expand inward, sweeping up the wind material.” say van Marle, “The presence of an expanding HII region changes the density structure of the nebula during the main sequence. Our main goal at this time is to simulate the circumstellar environment of stars between 25 M and 40 M at the time of the supernova explosion.”

Magic bubbles? Just stay out of the way when they pop!

Many thanks to JP Metsavainio of Northern Galactic for his magical personal image and allowing us this incredible look at distant beauty!

May 29, 2009December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast – May 29-31, 2009

Greetings, fellow SkyWatchers! Have you been watching the lovely crescent Moon as it climbs higher each night? What a beauty! With warmer nights in the northern hemisphere and cooler evenings bringing clear, deep views to the south – why not spend some time stargazing? We’ve got some great lunar features lined up for you to help you along with your lunar club challenges – as well as a bright galaxy and an interesting variable star. Time to dust off your optics and head out into the night…

Friday, May 29, 2009 – Today we begin with the 1794 birth on this date of Johann Heinrich von Madler who, along with Wilhelm Beer, published the most complete map up to that time of the Moon, Mappa Selenographia. How fitting, then, that we should visit the Moon tonight! We’re going in search of another Lunar Club Challenge that will prove difficult because you’ll be working without a map.

Relax! This will be much easier than you think. Starting at Mare Crisium, move along the terminator to the north following the chain of craters until you identify a featureless oval that looks similar to Plato seen on a curve. This is Endymion, and if you can’t spot it tonight don’t worry. We’ll look in the days ahead at some features that will point you to it!

Since tonight will be our last chance to galaxy hunt for a while, let’s take a look at one of the brightest members of the Virgo Cluster – M49 (RA 12 29 46 Dec +07 59 59). Located about 8 degrees northwest of Delta Virginis, and almost directly between a pair of 6th magnitude stars, the giant elliptical M49 holds the distinction of being the first galaxy in the Virgo Cluster to be discovered – and just the second beyond our local group.

At magnitude 8.5, this type E4 galaxy will appear as an evenly illuminated egg shape in almost all scopes, and as a faint patch in binoculars. Although a possible supernova event occurred in 1969, don’t confuse the foreground star noted by Herschel with something new! Most telescopes won’t be able to pick this region apart – especially with the Moon so near – but there are also many fainter companions near M49, including NGC 4470. A sharp-eyed observer named Halton Arp noticed them and listed them as ‘‘Peculiar Galaxy 134 ’’ – one with ‘‘fragments’’!

Saturday, May 30, 2009 – Today we begin with the 1423 birth of Georg von Peuerbachon this date, a follower of Ptolemy’s astronomy. Georg calculated eclipses; observed Halley’s Comet before it was so named; and created astronomical instruments. Following Georg nearly half a millennium later was Hannes Alfven, born in 1908. Alfven’s life work was plasma and its electric and magnetic forces. Lastly, we have Aleksei Arkhipovich Leonov, who was born in 1934. Leonov was the first man to climb out of a spacecraft (the Voskhod II ) and into space. He was the first true ‘‘astrophotographer’’ as he filmed for 10 minutes while orbiting!

Tonight let’s take our own journey to the Moon and look at a beautiful series of craters – Fabricius, Metius, and Rheita.

Bordered on the south by shallow Jannsen, Lunar Club Challenge Fabricius is a 78-kilometer diameter crater highlighted by two small interior mountain ranges. To its northeast is Metius, which is slightly larger, with a diameter of 88 kilometers. Look carefully at the two. Metius has much steeper walls, while Fabricius shows differing levels and heights. Metius’s smooth floor also contains a very prominent B crater on the inside of its southeast crater wall. Further northeast is the lovely Rheita Valley, which stretches almost 500 kilometers and appears more like a series of confluent craters than a fault line. The 70-kilometer diameter crater Rheita is far younger than this formation
because it intrudes upon it. Look for a bright point inside the crater, its central peak.

While the Moon is still west, let’s have a look at telescopic star W Virginis located about 3.5 degrees southwest of Zeta (RA 13 26 02 Dec -03 22 43). This 11,000 light-year-distant Cepheid-type variable is, oddly enough, a Population II lying outside the galactic plane. This expanding and contracting star goes through its changes in a little over 17 days and will vary between 8th and 9th magnitude. Although it is undeniably a Cepheid, it breaks the rules by being both out of place in the cosmic scheme and displaying abnormal spectral qualities!

Sunday, May 31, 2009 – Today we begin with noting the 1872 birth on this date of Charles Greeley Abbot, who may very well have been the first astronomer to suspect that the radiation from the Sun might vary over time, and thus it was technically a variable star. When Abbot became the director of the Smithsonian Astrophysical Observatory (SAO), the SAO established a network of solar radiation observatories around the world. After many decades of study, a connection was made between solar variations and weather on Earth.

Tonight the Moon will be our companion. Now well risen above atmospheric disturbance, this would be a great time to have a look for several Lunar Club Challenges you might have missed. Most prominent of all will be two craters to the north named Atlas and Hercules. The easternmost Atlas was named for the mythical figure who bore the weight of the world on his shoulders. The crater spans 87 kilometers and contains a vivid Y-shaped rima in the interior basin. Western Hercules is considerably smaller at 69 kilometers in diameter and shows a deep interior crater, called G. Power up, and look for the tiny E crater, which marks the southern crater rim. North of both is another unusual feature that many observers miss. It is a much more eroded and far older crater showing only a basic outline; this crater is known as Atlas E.

Since we’re here, let’s take a crater walk and see how many features we can identify. . . Good luck and clear skies!

Atlas region: (1) Mare Humboldtianum, (2) Endymion, (3) Atlas, (4) Hercules, (5) Chevalier, (6) Shuckburgh, (7) Hooke, (8) Cepheus, (9) Franklin, (10) Berzelius, (11) Maury, (12) Lacus Somniorum, (13) Daniel, (14) Grove, (15) Williams, (16) Mason, (17) Plana, (18) Burg, (19) Lacus Mortis, (20) Baily, (21) Atlas E, (22) Keldysh, (23) Mare Frigoris, (24) Democritus, (25) Gartner, (26) Schwabe, (27) Thales, (28) Strabo, (29) de la Rue, and (30) Hayn.

Until next week? Ask for the Moon, but keep on reaching for the stars!

This week’s awesome images are Johann Heinrich von Madler (historical image), M49 (credit—Palomar Observatory, courtesy of Caltech), Aleksey Arkhipovich Leonov (archival image), Fabricius, Metius, and Rheita (credit—Alan Chu), Charles Greeley Abbot (historical image) and Atlas region (credit—Greg Konkel, annotations by Tammy Plotner). We thank you!

May 28, 2009December 24, 2015 by Tammy Plotner

Kid’s Astronomy: Of Kings and Queens and Royal Things…

The month of May is a fine time for flowers and colors – and even getting married! There once was an old tradition where children took ribbons and ‘danced around the Maypole’ in circles, weaving patterns around a central focal point. Before the month is over, why not celebrate the flowers and the dance of the stars around the northern pole as well? Let’s take another look at a constellation that’s becoming very visible at this time of year as we visit “Kings and Queens and Royal Things”…

Right now, as evening begins, the constellation of Cepheus is directly below Polaris for the northern hemisphere. As the sky darkens, this collection of five moderately bright stars will slowly turn counter-clockwise around Polaris… moving first seeming eastward, only to rise high above the pole star during the late hours of the night and begin moving towards the west as the Sun rises. While you are looking for a place where you can see the northern horizon well, listen to the wind and you’ll hear the voice of of the night. It has a story for you…

“As legend tells it, there once was a king of ancient Aethiopia named Cepheus – whose Queen was the beautiful Cassiopeia. They had many children together and one of Cassiopeia’s favorite places was the royal garden. Now, Cepheus loved to please his wife, so in this garden he contructed her a temple with a pointed roof where she and the children could spend their days among the many flowers. Cassiopeia’s favorite bloom was the iris, and to this day you can still find the “Iris Nebula”, (NGC 7023) blooming nearby.”

“Over the years Cepheus and Cassiopeia had many children together and take their place among the stars. When their strong sons would go out hunting, Cassiopeia was said to have lighted a candle in the window the the garden temple to lead them home on a dark night. To this very day, its deep red glow can be seen as Mu Cephi, Herschel’s Garnet Star.”

Time passed and Cassiopeia gave birth to a daughter – Andromeda. So beautiful was the baby girl, that Cassiopeia would sit in her chair under a palm tree on the west side of the garden temple where she could show her daughter’s loveliness to the gods. Zeus thought Andromeda was beautiful as well, and so he bestowed upon her the “Little Cloud” we now know as the Andromeda Galaxy.

However, Cassiopeia was far too proud of her daughter and she boasted once too often on her good looks – proclaiming her to be even more beautiful than Zeus’ wife, Hera. This did not sit well with the Queen of the gods, so she demanded that Andromeda be sacrificed to Cetus, the Sea Monster – or marry her monster son, Calibos.

In order to save her daughter, Cassiopeia called upon one of Zeus’ mortal sons, Perseus to save her… But first Perseus had to win his winged horse, Pegasus, and defeat the Medusa. In order to gain his opportunity, Perseus had to answer a riddle. What is joined together but has no end?”

The answer was the double pearl ring worn by Calibos, and when Pereus retrieved the ring, the gods put it up in the sky where it remains as the fine double star cluster, NGC 869 and 884. Perseus then flew away on Pegasus to defeat the Medusa, and the gods placed her head in the sky. To this day, you can still see her eye – Algol – changing brightness rapidly and waiting to turn unwary watchers, and Sea Monsters into stone.”

So go out, before the Moon captures the sky in the nights to come and hides the faint stars. Are there any iris in bloom where you are? Can you find the Royal House of Cepheus? Watch as the night moves and see how it turns around the pole star, just like children dancing around a maypole. Did you know that for each night that passes, our sky progress by six minutes? For example, when you locate Cepheus, make note of the time you first spotted it and its position. Now, look again an hour later. This is where you will find Cepheus 10 days from now at the time you first located it! Check Cepheus’ position 3 hours later and this is where it will appear a month from now at your initial time.

Isn’t SkyWatching wonderful?!

Many thanks to Torsten Bronger for the Cepheus constellation map, Uranometria historical Cepheus image, the “Iris Nebula” courtesy of Kent Wood, the “Garnet Star” courtesy of Francesco Malafarina, Cassiopeia courtesy of the University of Florida, M31 courtesy of Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF and the “Double Cluster” courtesy of N.A.Sharp/NOAO/AURA/NSF. We thank you!

May 22, 2009October 17, 2017 by Tammy Plotner

Kid’s Astronomy – Draco: Enter The Dragon

Kids of all ages! With no Moon around to light up the weekend skies, isn’t it time to spend an evening outside an enjoy the stars? With Spring in the air in the northern hemisphere, the nights are much warmer and a welcome time to observe the glittering jewels that turn around Polaris, the “North Star”. This time we’re off on an adventure to help you identify the eight largest constellation in the night – Draco the Dragon…

As the skies get dark tonight, go out and do some stargazing. One of the brightest you will see will be almost overhead – the planet Saturn. Do you recognize the “Big Dipper” – Ursa Major – to the north? Good! Connect the dots of the two stars on the front of the dipper and they will point the way to Polaris. Once you have this star in site, you are ready to find the Draco constellation. It’s a long, glittering chain of faint stars that curls around between Ursa Major and Polaris on the east side. Watch as the night goes on and the Dragon climbs higher. By midnight its stars will have curled over the top of Polaris!

Listen… Do you hear a voice on the wind? I think it has a story for you…

“What “knight’s” tale would not be complete without a battle with a dragon? Almost every ancient culture has a dragon in its myths! These huge serpents were believed to have a body like a huge lizard, or a snake with two pairs of lizard-type legs, and able to emit fire from their mouths. Even our English word, dragon, comes from the Greek word “drakon” meaning huge serpent! Perhaps the largest of all known dragons is portrayed in stars… the constellation of Draco.”

“Finding Draco isn’t easy, but begin before dark and look to the north. As the stars come out one by one, look for a long ribbon of faint stars which encircles Polaris – the “North Star”. If you have a telescope, you can take a look into the eye of the Dragon! NGC 6543, is one of the brightest planetary nebula in the sky and you can find its small, blue green disc even with binoculars.”

“But, do dragons really breathe fire? No, but the constellation of Draco is host to six different meteor showers. The best of all occurs around the middle of September every year, so be sure to watch. Perhaps it is the Japanese dragon “Ryu” and he will grant your wish!”

Images that accompany this article are: Historical Draco Figure from Uranometria, Draco Map Created by Torsten Bronger, Dragon Eggs Screensaver, and Animation by Michelet B. We thank you!

May 22, 2009December 24, 2015 by Tammy Plotner

Weekend SkyWatcher’s Forecast – May 22-24, 2009

Greetings, fellow SkyWatchers! Are you ready for a dark sky observing weekend? Then let’s take a ride with Wild’s Triplets, join Markarian’s Chain gang and hang out with the night Owls. Are you ready? Then grab your telescopes and binoculars and I’ll see you in the backyard….

Friday, May 22, 2009 – Let’s begin the day by honoring the 1920 birth on this date of Thomas Gold, an astronomer known for proposing the ‘‘steady-state’’ theory of the universe; for explaining pulsars; and for giving the magnetosphere its name. Gold was also an auditory research genius. In his interview with D.T. Kemp he stated:

‘‘I’m a compulsive thinker, I never turn my brain off, I’ve never in my life complained of being bored because I’m constantly thinking about some problem, mostly physics I suppose. A problem is always on my mind – evidently even in my sleep because I often wake up with a solution clearly spread out.’’

For the large telescope and seasoned observer, the challenge for this evening will be 5.5 degrees south of Beta Virginis, and one half degree west (RA 11 46 45 Dec -03 50 53). Classified as Arp 248, and more commonly known as ’’Wild’s Triplet,’’ these three very small interacting galaxies are a real treat! Best with around a 9-mm eyepiece, use wide aversion, and try to keep the star just north of the trio at the edge of the field to cut glare. Be sure to mark your Arp Galaxy challenge list!

Saturday, May 23, 2009 – Tonight let’s hop to far northern skies for a look at two gems. Start with Beta Ursae Majoris – the southwestern star of the Big Dipper – and begin scanning about a finger-width southeast for M108 (RA 11 11 31 Dec +55 40 31). At magnitude 10, you’ll appreciate this splendid edge-on galaxy! Discovered by Pierre Mechain on February 19, 1781, and later verified by Charles Messier, it didn’t formally enter the Messier’s catalog until 1953 at the hand Owen Gingerich. Despite its low surface brightness, M108 can be spotted by mid-aperture telescopes, and larger scopes will make out irregular patches of detail.

Now, hop on less than a finger-width further southeast (RA 11 14 47 Dec +55 01 08) where you’ll spot M97, the ‘‘Owl Nebula.’’ Discovered by Pierre Mechain 3 days earlier than M108, the Owl is often thought of as one of the most difficult of the Messier studies to detect from urban locations… and it may require a light pollution filter to help bring it to life. About the apparent size of Jupiter, the Owl gets its name from the vague gray-greenness of its light, and the two curious eye-like voids visible through larger scopes. Scientists believe the voids are the result of a line-of-sight phenomenon, where the lowest-density poles lie at an oblique angle from our vantage point. The structure of M97 and its fluorescence are associated with a high surface temperature central star in the last stages of life. Can you spot the faint 16th magnitude dying star at its heart?

Sunday, May 24, 2009 – Tonight is the New Moon and time to tour the galaxy fields of Virgo. For large telescopes, this is the ‘‘field of dreams’’… Start four finger-widths east-southeast of Beta Leonis for part of ‘‘ Markarian’s Chain ’’ and discover M84 and M86 (RA 12 25 03 Dec +12 53 13)! Good binoculars and small telescopes reveal the matched ellipticals of M84/86, while mid-sized telescopes will note that western M84 is slightly brighter and smaller. Larger scopes see these two galaxies literally ‘‘leap’’ out of the eyepiece at even modest magnifications!

In large telescopes, the bright galactic forms of M84/86 can be held with direct vision, while aversion welcomes many other mysterious strangers into view. Forming an easy triangle with the two Messiers, and located about 200 south, is 11th magnitude NGC4388, a classic edge-on spiral. Dim NGC4387 (magnitude 12) appears in the center of a triangle as a small face-on spiral with a noticeable dust lane. In large scopes, the central structure forms a curved ‘‘bar’’ of light, and the dust lane cleanly separates the central bulge of the core. East of M86 are two brighter NGC galaxies – 4435 and 4438.

In an average telescope, NGC 4435 has a simple star-like core and wispy round body structure, while NGC 4438 is a dim elliptical. The beauty of the pair is their proximity to each other! At times, a conspicuous wisp of galactic material can be seen stretching back toward the nearby (brighter) galaxy pair M84/86. Happy hunting!

Until next week? “Keep on rockin’ in the free world…”

This week’s awesome images are (in order of appearance): Thomas Gold (historical image), Arp 248: Wild’s Triplet (credit—Adam Block/NOAO/AURA/NSF), M108 and M97 (credit—Palomar Observatory, courtesy of Caltech) and Wide-field image of the Virgo galaxy cluster with M84/86 region to the upper right (credit—NOAO/AURA/NSF). We thank you so much!

May 21, 2009December 24, 2015 by Tammy Plotner

IYA Live Telescope Today: M104, NGC 6231, NGC 55 and Comet C/2009 G1 (STEREO)

Were you tuned in to Galactic TV today? If not, you missed a real treat. The southern skies were exceptionally clear and dark. And you know what happens when you’re photon-deprived, don’t you? Darn right… We played all night. If you didn’t get a chance to see the action, don’t despair. Believe it or not, we really and truly care about giving you an opportunity to see through the eyepiece, too… That’s why we took videos of all of tonight’s objects to share. Why not step inside and have a look at the mysterious Sombrero Galaxy, beautiful open cluster NGC 6231, huge barred irregular galaxy NGC 55 and a surprise treat… Comet C/2009 G1 (STEREO)!

I couldn’t wait to get upstairs to my office today and for the skies to get dark in Central Victoria. I had a feeling that the IYA Live Telescope was going to be doing some great things and I wasn’t disappointed. First object up? M104… the Sombrero Galaxy…

The Sombrero Galaxy (also known as M104 or NGC 4594) is an unbarred spiral galaxy in the constellation Virgo. It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its inclined disk. The dark dust lane and the bulge give this galaxy the appearance of a sombrero. The galaxy has an apparent magnitude of +9.0, making it easily visible with amateur telescopes. The large bulge, the central supermassive black hole, and the dust lane all attract the attention of professional astronomers.

Sure, the Sombrero is cool and I loved every second of it. But… About the time I had my coffee finished, I had Uranometria open and digging for some southern studies. Chances are I’ll never be well enough, nor rich enough, to visit ‘down under’ so I really want to see some of these clusters with my own eyes. I want to sketch them… Log them… Look up their RA and Dec. I want to call them my own… I want to beg Bert (our intrepid volunteer at Southern Galactic Telescope Hosting who stays up all night just to aim this scope for us for free cuz’ he’s cool… ) to move that scope!

Next up? NGC 6231….

NGC 6231 is an open cluster located near Zeta Scorpii. Zeta1 and Zeta2 Scorpii are members of this star cluster. This cluster is estimated about 3.2 million years old, and is approaching the Solar System at 22 km/s. Very young stars including it, belong to the Scorpius OB association. Zeta1 Scorpii (spectral type O8 and magnitude 4.71.[1]) is hottest star in it. It was discovered by Giovanni Batista Hodierna before 1654. Hodierna listed it as Luminosae[2] in his catalogue of deep sky observations. This catalogue was included in his book De Admirandis Coeli Characteribuse published in 1654 at Palermo. It was independently observed by other astronomers after Hodierna.

Aaaaaaah…. What a beauty! Totally satisfied, I put my sketches away in my desk, logged my information and settled into work. Why be a scope hog? I logged off to give others some free air space and next thing you know? Well, Bert is tugging on my virtual sleeve and telling me to look again. Holy cow… Check this out! He’s got NGC 55 in!!

NGC 55 is a barred irregular galaxy located about 7 million light-years away in the constellation Sculptor. NGC 55 and the spiral galaxy NGC 300 have traditionally been identified as members of the Sculptor Group, a nearby group of galaxies in the constellation of the same name. However, recent distance measurements indicate that the two galaxies actually lie in the foreground. It is likely that NGC 55 and NGC 300 form a gravitationally bound pair.

Well, I didn’t think anything could top that. I watched fascinated as the pencil slim galaxy filled the whole screen and the nucleus would scream in and out. I couldn’t believe how huge it was! Structure… my word… We’ve got structure coming out of an edge-on galaxy in a little bitty scope set on the edge of the world. So, I start digging around for my pencils and paper again. More sketches? Yeah. More sketches.

Then Bert really lays one on me. He’s going to try for something even I wouldn’t dream our little IYA scope could pick up. He asks me for some information and brother? I’m on it. I guarantee you within 180 seconds we both had the epoch and charts ready and I even had the coordinates. The instant message said he had to stop for a few minutes to dark adapt and we were going for it… Could it be? Could it happen? Yeah. It did.

Our final target for the day was Comet C/2009 G1 (STEREO). At magnitude 10.2 (RA 0h 37m 26s Dec 37°36’6″) we weren’t going to set any records for showing it bright and beautiful – but considering we’re running with an 80mm scope, we aren’t doing too bad! It’s faint, but it’s darn near center and if you’re good at the eyepiece? You can’t miss it.

Have a look…

Comet C/2009 G1 was discovered by Jiangao Ruan of China who found the 10th magnitude fuzz ball on images taken by the SECCHI HI-1B instrument onboard one of the STEREO spacecraft. Since the comet was discovered in spacecraft data it was naturally named after the spacecraft – and thus the name STEREO. Pretty cool considering the data is public domain and the person who caught it out was an amateur watching what was going on! Congratulations to Jiangao on his 19th find from SOHO and STEREO data in less than a year!

So, while Bert filmed the video for you to try and capture the movement of the comet, I called every comet watcher I knew on the telephone and we were all glued to our monitor screen sketching this comet and comparing star charts and logging the stars for our records. Once crazy? Always crazy. I guess even having a Comet Hunter’s Gold Medal hasn’t stopped the fever! (Hopefully those of you who are also working on your AL comet studies will take the clues I’ve left you and do the same!)

Well, I hope you had as much fun viewing the videos as we did taking them for you! As always, check the IYA Live Telescope for broadcasts whenever you get a chance. We’re working on picking up other observatories around the world and maybe before the end of the year we’ll even be running something 24/7! (yeah, rite… like there’s somewhere in the world that’s not cloudy all the time?)

Italicized information is a direct quotation from Wikipedia and we appreciate it!

May 20, 2009December 24, 2015 by Tammy Plotner

IYA Live Telescope Today: Jupiter and Neptune Conjunction – M19

Hey, hey! We’re baaaack… Due to some technical difficulties, our eye on the southern sky has been down for a short time, but I’m happy to report that we’re back up and running again. If you missed our broadcast yesterday and today, have no fear. We recorded the Jupiter and Neptune conjunction for you and captured Messier 19 today, too! Come on… You know you want to look!

Even though it only looks like two dots hanging out on a black background, it’s knowing what those two dots are that counts. In order to get them both in the same frame, we used minimal magnification. Jupiter is the brightest and will appear at the bottom of the frame, while Neptune is fainter and at the top of the frame.

Ready for the next? Then step up to the eyepiece and view Messier Object 19….

(The following is a cut and paste from Wikipedia)

Messier 19 or M19 (also designated NGC 6273) is a globular cluster in the constellation Ophiuchus.

It was discovered by Charles Messier in 1764 and added to his catalogue of comet-like objects that same year.

M19 is the most oblate of the known globular clusters. It is at a distance of about 28,000 light-years from the Solar System, and is quite near to the Galactic Center, at only about 5,200 light-years away.

As always, you can visit the remote telescope by clicking on the IYA “LIVE Remote Cam” Logo to your right. Just remember if you get an error message, that means it is either daylight or cloudy… Or the scope or broadcasting system is dead and so are the volunteers running it. We’ll be broadcasting whenever skies are clear and dark in Central Victoria! Enjoy…

Factual information is copied from Wikipedia. Thank you so much!

May 20, 2009December 24, 2015 by Tammy Plotner

Flying Saucers? The Fun Is For Real…

On a recent trip to Canada in the great province of Ontario, I found a quiet corner on Lundy’s Lane. I had been enjoying the scenic beauty of Niagara Falls and to break away for the tourist aspect seemed like a welcome respite. How could someone who lives, eats and breathes space 24/7 pass up an opportunity to visit a place like this? The answer was… I couldn’t.

For any one old enough to remember and still too young to resist, the retro-styling and drive-in atmosphere of this super clean diner was enough to make you smile the moment you stopped in the parking lot. Glittering multi-colored lights and a welcoming glow was all I needed to take a chance. Once inside I was transported back to all of my childhood fantasies, and despite having a well stocked refreshment area – all you really wanted was a cold soda or a milk shake. Why spoil the fun?

When the menu came, my grin got even wider. There’s nothing that delights me more than a sense of humor… and to combine it with good food makes the experience even more extraordinary. Needless to say, I didn’t just stop by this place on a whim. I’d researched my restaurants in advance and every sample around the family table proved to be just as tasty and well prepared as the reviews promised. The “Jupiter Burgers” were absolutely among the finest I’ve ever eaten and the clam chowder didn’t come out of can, my friends. Even though the hour was late, I had a delightful time talking to the “natives” who were patient with my questions and seemed to enjoy the company as much as we enjoyed theirs!

Right down to the little stuffed aliens…

So what’s a less than serious piece about finding a flying saucer restaurant doing in a serious astronomical webpage like Universe Today? It’s to remind you to take a chance on what you love. If you love astronomy and having dinner in a restaurant shaped like a flying saucer looks like fun? Do it! You may end up in some remote corner of Iowa having the worst cup of coffee you’ve ever tasted… Or you might end up in a quiet corner of Niagara Falls surrounded by your laughing family enjoying diner food at it’s best.

Because the fun is what’s for real…

Thanks to Richard Weiss for the additional image!