The Monthly Newsletter of the Bays Mountain Astronomy Club...stars as Boötes and Virgo....

The Monthly Newsletter of the

BaysMountain AstronomyClub

Edited by Adam Thanz M o re o n t h i s i m a g e .

S e e F N 1

May 2017

Chapter 1

Looking Up

B r a n d o n S t ro u p e - B M A C C h a i r

M o re o n t h i s i m a g e .

S e e F N 2

Hello BMACers,

Welcome to the month of May. We are inching closer and closer to the summer season. Some of the days lately already feel like summer is in full swing. Some like that and some do not. One good thing about coming into this time of year is the awesome celestial objects in our sky. This best, in my opinion, would be the Summer Milky Way. If you are lucky enough to be in good, dark skies, the Milky Way is just spectacular this time of year. You can just get lost in the dense stellar dusk of our own beautiful galaxy. Another aspect of this time of year that some of you may look forward to is that this month marks the end of the school year. You know who you are! All kidding aside, congratulations on making it to the end whether you are a student or a teacher. I wish you luck on all your future endeavors.

For our meeting this month, we will once again welcome some of Tom Rutherford’s students. We always reserve the month of May for Tom to bring a few of his students to give their, in most cases, award winning presentations. Tom is a member of our Astronomy Club, the Bristol Astronomy Club, and a science teacher at Sullivan South High School in Kingsport. Every year, some of his

students are chosen to give their presentations at local and regional science fairs. Some even make it to the national level. One of the topics for the presentations this year will be on the rotational period of an asteroid, another will be on the effects of x-rays on seeds, one will be on a high-altitude balloon launch, and another will be on an exoplanet transit. I am really looking forward to these presentations. We seem to never be disappointed in any of the students’ presentations. Please come out and show your support for these young minds and their love for the sciences.

At our April meeting, we once again got to enjoy a planetarium show. Everyone saw a special showing of “Comets & Discovery” and got to enjoy an always fun, constellation tour. This was aimed to get everyone primed for the StarWatch viewings. I hope everyone was able to make it and had a good time. I, unfortunately, was unable to be there because I was out of town on a special trip that I will talk about a little later. Please read the short review by Adam following my article.

I do want to take a second and apologize to all the members for my absence for the past two months. The first month, I had to

Brandon Stroupe

Looking Up

Bays Mountain Astronomy Club Newsletter May 2017 3


S e e F N 3

4 Bays Mountain Astronomy Club Newsletter May 2017

Virgo

Image from Stellarium

attend an event for my employer and the second month was when I was out of town on a trip. I do promise to avoid missing any months that I possibly can. I hope that everyone understands.

Our constellation this month will be Virgo. Virgo is typically linked to Dike, the Greek goddess of justice, and Persephone, the daughter of Demeter, the harvest goddess. According to Greek mythology, the Earth experienced eternal spring until the god of the underworld abducted the spring maiden Persephone. Another myth identifies Virgo as Erigone, the daughter of Icarius of Athens. Icarius, who had been favored by Dionysus, was killed by his shepherds while they were intoxicated and Erigone hanged herself in grief. Dionysus placed the father and daughter in the stars as Boötes and Virgo. Interestingly, Virgo is the largest constellation of the Zodiac and the second-largest constellation overall, behind Hydra. Virgo is easily found through its brightest star, Spica. There is also an abundance of deep-sky objects in this constellation. Some of them include: M104 (also known as the Sombrero Galaxy), M49, M58, M59, M60, M61, M84, M86, M87, M89, and M90. All of these are galaxies, either elliptical or spiral. And if that wasn’t enough for this constellation, Virgo is also home to over 26 known exoplanets. This constellation really does have a lot going on. When you are out this month, be sure to give Virgo a few minutes of your time.

As I mentioned earlier, I was unable to attend last month’s meeting because I was on a special trip. The trip I was on was to an astrophotography and astronomy convention. The astrophotography convention was called NEAIC (Northeast Astro Imaging Conference) and the astronomy convention was called NEAF (Northeast Astronomy Forum). Some of you may have heard of them or may have even been to one or both. If you have not, I highly recommend taking the time to go one year. The events are held in Suffern, NY, just outside of New York City. They are both 2 day events. NEAIC has everything that an astro-imager dreams of. Presentations, workshops, vendors, and of course, door prizes. Best of all, you get to meet and talk to the authors of nearly every astro image you have drooled over in books and magazines. If you are not interested in astrophotography, NEAF would be the way to go. It is held in the gymnasium of the local college and it is massive. Probably close to every vendor and astronomy related company is set up there. You get to see new, upcoming products in the astronomy world, talk to the editors of astronomy magazines, listen to talks from some of the most notable people in the business, and of course, buy stuff. Trust me, there is plenty of stuff to buy. Seriously, you could easily go broke here… I will be happy to talk more about it if you would like. Just let me know. [Ed.: I think this would be a cool presentation by both Brandon and Dan…]

That will be it for this month. Just a reminder that the StarWatches ended in April. I would like to thank everyone that



A panorama of NEAF.

NEAF 2017 - All Photos by Brandon Stroupe


Hercules Telescopes


NASA


Sky-Watcher


Celestron


Space.com


Explora Dome


iOptron


TEC (notice their neighbor, the Antique Telescope Society)


Solar viewing


More solar viewing


The host site, Rockland Community College

took the time to come out and help with showing the public our wonderful night sky. We could not do this without you. The SunWatches will continue as usual. If you would like to volunteer to help with the SunWatches, please arrive a little before 3:00 p.m. to help with setup. The scopes are setup at the dam.

Also, as I am writing this, we are coming close to Astronomy Day. It is on April 29th this year. I hope that the day will turn out well and that we will be able to interact and show many people the wonders of our great Universe and the great science of astronomy. Until next month… Clear Skies.

April 2017 meeting review by Adam Thanz:

The April 7th meeting went well. We showed “Comets & Discovery” and followed that with a shared, “pass the pointer” activity in which we all pointed to different celestial objects in the planetarium theater using the Carl Zeiss ZKP-4 star projector. Many stars, constellations, asterisms, and deep sky objects were pointed. We even took a dip into the southern sky to enjoy some lesser-known objects to our members like the Southern Cross and the Magellanic Clouds!

Astronomy Day is on April 29, 2017. Displays with member interpretation will be held for the public 1-4:30 p.m. either just outside the Nature Center or in the main lobby depending on the weather. But, please show up by noon to help set up. Solar viewing is officially just the 3-3:30 p.m. time slot, but can be

longer based on member volunteerism. By 5 p.m., the displays will be packed up and we’ll all go out to dinner somewhere. Night observing will start at 8:30 p.m., but we’ll need to be back to set up by 7:30. If you would like to help, please do so! Come at noon to help set up and also see about planning on running a display with an astronomical topic of your choice.


Chapter 2

BMACNotes


S e e F N 4

BMAC Youtube!The BMAC has a YouTube channel. Click here to see what's on!

(https://www.youtube.com/channel/UCwIQM6nUs9qxJtDQe4AaAWQ)

There are now four entries in our channel. Check them out!

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Calhoun Stargaze 2017Come join regional amateur astronomers at the Calhoun County Dark Skies Park in West Virginia on Friday May 19th thru Sunday May 21st 2017 for a Starparty Convention.

Calhoun County Park, located just south of Grantsville WV, is one of the darkest spots in the Eastern U.S. Skies at Calhoun can easily reach 7th magnitude. The park is located a little NW of the center of West Virginia, and sits on a ridge with an elevation of around 1,100-ft.

Attendance for this year is limited to a total of 50 registrations, so please RSVP no later than Friday, May 5th! The cost of the two night camping event is only $30 USD per family, and includes dinner on Friday, three meals on Saturday, and a farewell

breakfast on Sunday. Major financial sponsorship has allowed for these greatly reduced fees.

https://www.eventbrite.com/e/calhoun-stargaze-2017-tickets-32357216305?ref=enivtefor001&invite=MTE4Nzg2NDMvdGhhbnpAa2luZ3Nwb3J0dG4uZ292LzA%3D&utm_source=eb_email&utm_medium=email&utm_campaign=inviteformalv2&utm_term=eventpage

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BMAC News



S e e F N 3

https://www.youtube.com/channel/UCwIQM6nUs9qxJtDQe4AaAWQ
















Chapter 3

Celestial Happenings

J a s o n D o r f m a n


S e e F N 5

Last month’s battle between winter and spring has finally ended and spring has emerged victorious! (Big surprise…) Temperatures have warmed a bit in April and with it we are seeing a few more showers. Hopefully, these April showers will mean more clear skies in May. Should you find yourself venturing outside on a clear night in May, there are a few planets to observe, some close pairings with the Moon, a comet and a weak meteor shower.

PlanetsMars continues to shine in the west as it comes to the end of its year-long appearance in our evening skies. By month’s end, the “Red Planet” will begin to get lost in the glow of the twilight sky. It is currently about magnitude 1.6 and will fade to magnitude 1.7 as the month progresses.

For May, Jupiter is still the dominant planet for evening observations. Look for it about 35˚ above the southeastern horizon an hour after sunset. At magnitude -2.4, Jupiter is the most brilliant point of light in the evening sky.

I’m sure many of you are just as excited as I am for the upcoming total solar eclipse. When this occurs, the Moon is casting its shadow onto the surface of Earth. There are some fascinating photos taken from ISS and other satellites during an eclipse that show the Moon’s shadow on the surface of Earth. Most of us, however, will never get the opportunity to venture in space and see this as its happening. But, we can see this occurring elsewhere in the Solar System. Jupiter, with its four Galilean moons and just a slight tilt of its axis, has total solar eclipses quite regularly. We see these events as shadow crossings on the surface of Jupiter. This month and next, there will be several twin shadow crossings that provide a more challenging observation of the “King of the Planets.” They will occur on:

May 11 at 9:59 p.m.

May 18 at 11:54 p.m.

May 26 at 1:47 a.m.

May 27 at 8:16 p.m.

Jason Dorfman

Celestial Happenings



S e e F N 3

The May 27 event involves Io and Ganymede, the largest moon of Jupiter. The remaining dates feature Io and Europa, the two Galilean moons closest to Jupiter. Look for dark spots on the cloudtops of the planet. The crossings are brief, lasting 6 to 35 minutes.

Saturn rises in the southeast just as Jupiter is crossing the meridian due south around 11:30 p.m. By month’s end, Saturn will rise two hours earlier. The ringed world is currently in retrograde. It is in Sagittarius and will trek westward into Ophiuchus just after mid-month. It is fairly bright at about magnitude +0.2 for the month. Also, the ring plane is still quite open to us at 26˚.

If you haven’t been keeping up with the Cassini mission at Saturn, the spacecraft is running low on fuel and has begun its grand finale. Starting in April and continuing to September, Cassini will be making its closest approaches to the planet with several flybys between the ring plane and the planet. This will provide the closest look at the inner rings and ultimately the atmosphere of Saturn. For the last couple of flybys, the craft will skim the cloud tops and end the mission by burning up as it enters the atmosphere. The mission team chose this end for Cassini to prevent possible contamination from the spacecraft with the moons of Saturn that may have favorable conditions for life, such as Enceladus. Come and see our “Appalachian Skies” program in

the planetarium during the months of May and June for a informative video about this from NASA.

This month, it may be worth getting up early for some morning observations to catch brilliant Venus. Venus reached its maximum illuminated extent on April 30th and is heading towards its greatest western elongation on June 3rd. The month opens with Venus at a very bright magnitude -4.7. It will dim slightly to -4.5 by month’s end. For telescope and binocular observers, there will be lots of visual changes to Venus’ appearance this month. On May 1, the disk of the planet spans about 38” of sky and shows 25% illumination. As the month ends, Venus will have moved away from Earth a bit, reducing the apparent diameter of the disk to 25” but increasing the illuminated area to almost half.

LunaIn the beginning of May, we find a crescent Moon in the evening sky reaching first quarter on May 3. Full Moon occurs on May 10. Be sure to look for it on May 7 when a gibbous Moon passes just 2˚ north of Jupiter and then on May 13 as it will be 3˚ north of Saturn.

Comet 41P/Tuttle-Giacobini-Kresak(T-G-K)If you didn’t find an opportunity to look for this comet, this may be the month to make that observation. The comet reached perihelion on April 12. Current observations have it at about magnitude 7, so definitely a binocular or telescope observation. Some predictions have it reaching mag 6 in early May, but it will



Comet 41P Tuttle-Giacobini-Kresak on April 2, 2017

The bright star is Thuban; FOV 1.65° x 2.48°; ISO1600, 30s, 130mm refractor, f.l. 819mm, f/6.3

The sky was poor with haze and humidity and the almost first-quarter Moon up. This forced me to a short exposure to keep the sky brightness down. You can see the green, hazy coma and a small nucleus. The night before was far better with very clear, dark skies and steady, but the comet was still difficult in

binoculars. A faint, green hazy patch with essentially no nucleus. No wonder we didn’t see it during StarWatch on April 1. Photo by Adam Thanz

most likely dim to mag 8 as we reach the end of the month. However, the reason to pay attention to this comet is for a possible outburst, which has occurred with it several times in the past. During the month, it will be moving southward through Hercules. [Ed.: The comet is greenish and has a very low surface brightness. It’s bolometric magnitude may be around 7, but the coma is probably mag. 10-11. As such, the coma is distended and is barely viewable with binoculars in a very dark sky. It is also very difficult with a telescope. I would recommend an RFT or spotter. See the photo in this issue.]

Eta Aquariids Meteor ShowerThis is not a strong shower for the Northern hemisphere with a medium rate of 10-30 per hour. The peak occurs on the night of May 6-7 when you may find some swift meteors with persistent trains, but few fireballs. Unfortunately, there is a waxing gibbous Moon at that time, so best observations may be in the pre-dawn hours around 4 a.m. once the Moon has set.

That’s all for this month. Clear Skies!


Chapter 4

TheQueenSpeaks

R o b i n B y r n e

One of my holiday gifts this past year was the book “The Copernicus Complex: Our Cosmic Significance in a Universe of Planets and Probabilities” by Caleb Scharf. Given our recent trip to Poland, seeing the name of Copernicus got me excited. Although the book turned out to have very little to do with Copernicus, it was still an enjoyable and thought-provoking read.

The premise of the book is to explore the question of whether we, humans on planet Earth, are “special” or not. Prior to Copernicus and the heliocentric model, people assumed we were special and that was evidenced by our location at the center of all creation. When planet Earth was delegated to just one of the planets orbiting the Sun, the pendulum shifted in the other direction, assuming that we are ordinary - a dime a dozen. Scharf explores a variety of avenues to see whether we are, indeed, special or ordinary.

He begins by exploring astronomical clues. We orbit a star that is often referred to as “average,” when, in fact, far more stars are smaller than the Sun than are larger. We reside in a Solar System with terrestrial planets close to the star, and jovian planets located at larger distances. When looking at the systems of

planets found so far, we do not resemble what we are finding. We are located at an ideal distance from our star for liquid water to be plentiful. We have sufficient atmosphere to maintain liquid water and life. We live in an era of the Universe when enough high mass stars have died to provide, in sufficient quantities, the elements necessary for life as we know it to exist. We reside in a galaxy located in a sparsely populated cluster of galaxies, with infrequent galactic collisions. Our galaxy has enough gas and dust to sustain star formation. In many ways, it appears as though, astronomically speaking, we lucked out.

Having a background in astrobiology, Scharf next explores the conditions necessary for life to exist and evolve. I’ll be honest, since biology is not my strong point, this section was tougher for me to go through. He looked at the initial chemistry needed to produce the building blocks for life, and found that the elements involved and the necessary reactions would be quite common. Exploring the kinds of conditions necessary for life to exist, he looked not just at the more typical kinds of life found on Earth, but also the extremophiles that reside in some of the harshest environments our planet can dish out. So, while life is very

Robin Byrne

Happy Birthday Elisabeth Hevelius



S e e F N 3


The cover for “The Copernicus Complex”

by Caleb Scharf

abundant on Earth, there is definitely a sampling bias. We live on a planet inhabited by life forms, so, of course, there will be lots of life here. Is life on Earth even representative of life that could evolve on other planets in different circumstances? There are many unknowns when we enter this realm.

Finally, Scharf invokes probability theory to explore the likelihood of various conditions, both astronomical and biological, to see whether we are unique or not. Without giving too much away, the final answer is both yes and no. In some ways we appear to be quite unique, while in others we are not. That may not be the most satisfying answer, but it is the most reasonable. There are aspects to where and when we live in the Universe that are quite common, while other parts are quite unusual. Having life may not be that unusual, but evolving to our level of intelligence and technology may end up being rare.

If you are interested in a book that explores these kinds of philosophical questions, while reviewing some of what we know about astronomy, biology, and statistics, “The Copernicus Complex” may just be the book for you.

Reference:

The Copernicus Complex: Our Cosmic Significance in a Universe of Planets and Probabilities” by Caleb Scharf; Scientific American; 201430 Bays Mountain Astronomy Club Newsletter May 2017

Chapter 5

Space Place


S e e F N 6

Later this year, an ambitious new Earth-monitoring satellite will launch into a polar orbit around our planet. The new satellite—called JPSS-1—is a collaboration between NASA and NOAA. It is part of a mission called the Joint Polar Satellite System, or JPSS.

At a destination altitude of only 824 km, it will complete an orbit around Earth in just 101 minutes, collecting extraordinarily high-resolution imagery of our surface, oceans and atmosphere. It will obtain full-planet coverage every 12 hours using five separate, independent instruments. This approach enables near-continuous monitoring of a huge variety of weather and climate phenomena.

JPSS-1 will improve the prediction of severe weather events and will help advance early warning systems. It will also be indispensable for long-term climate monitoring, as it will track global rainfall, drought conditions and ocean properties.

The five independent instruments on board are the main assets of this mission:

• The Cross-track Infrared Sounder (CrIS) will detail the atmosphere’s 3D structure, measuring water vapor and

temperature in over 1,000 infrared spectral channels. It will enable accurate weather forecasting up to seven days in advance of any major weather events.

• The Advanced Technology Microwave Sounder (ATMS) adds 22 microwave channels to CrIS’s measurements, improving temperature and moisture readings.

• Taking visible and infrared images of Earth’s surface at 750 meter resolution, the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument will enable monitoring of weather patterns, fires, sea temperatures, light pollution, and ocean color observations at unprecedented resolutions.

• The Ozone Mapping and Profiler Suite (OMPS) will measure how ozone concentration varies with altitude and in time over every location on Earth’s surface. This can help us understand how UV light penetrates the various layers of Earth’s atmosphere.

• The Clouds and the Earth’s Radiant System (CERES) instrument will quantify the effect of clouds on Earth’s energy balance, measuring solar reflectance and Earth’s radiance. It

Ethan Siegel

NOAA’s Joint Polar Satellite System (JPSS) to Monitor Earth as Never Before



S e e F N 3



S e e F N 8

will greatly reduce one of the largest sources of uncertainty in climate modeling.

The information from this satellite will be important for emergency responders, airline pilots, cargo ships, farmers and coastal residents, and many others. Long and short term weather monitoring will be greatly enhanced by JPSS-1 and the rest of the upcoming satellites in the JPSS system.

Want to teach kids about polar and geostationary orbits? Go to the NASA Space Place: https://spaceplace.nasa.gov/geo-orbits/

This article is provided by NASA Space Place. With articles, activities, crafts, games, and lesson plans, NASA Space Place encourages everyone to get excited about science and technology. Visit spaceplace.nasa.gov to explore space and Earth science!

Caption: Ball and Raytheon technicians integrate the VIIRS Optical and Electrical Modules onto the JPSS-1 spacecraft in 2015. The spacecraft will be ready for launch later this year. Image Credit: Ball Aerospace & Technologies Corp.


https://spaceplace.nasa.gov/geo-orbits/

https://spaceplace.nasa.gov/geo-orbits/

Chapter 6

BMAC

Calendar

and more


S e e F N 7

BMAC Calendar and more



S e e F N 3

Date Time Location Notes

B M A C M e e t i n g sB M A C M e e t i n g sB M A C M e e t i n g sB M A C M e e t i n g s

Friday, May 5, 2017 7 p.m. Nature CenterDiscovery Theater

Program: Some of the astronomy students at Sullivan South High School will join their educator, Tom Rutherford, and speak about their continuing astronomy research. Topics include the rotational period of an asteroid, the

effects of x-rays on seeds, a high-altitude balloon launch, and an exoplanet transit.; Free.

Friday, June 2, 2017 7 p.m. Nature CenterDiscovery Theater Program: Topic TBA; Free.

Friday, August 4, 2017 7 p.m. Nature CenterDiscovery Theater Program: Topic TBA; Free.

S u n W a t c hS u n W a t c hS u n W a t c hS u n W a t c h

Every Saturday & SundayMarch - October

3-3:30 p.m. if clear At the dam View the Sun safely with a white-light view if clear.; Free.

S t a r W a t c hS t a r W a t c hS t a r W a t c hS t a r W a t c h

Mar. 4, 11, 2017 7:00 p.m.

Observatory View the night sky with large telescopes. If poor weather, an alternate live tour of the night sky will be held in the planetarium theater.; Free.Mar. 18, 25, 2017 8:00 p.m. Observatory View the night sky with large telescopes. If poor weather, an alternate live tour of the night sky will be held in the planetarium theater.; Free.

Apr. 1, 8, 15, 22, 29, 2017 8:30 p.m.

Observatory View the night sky with large telescopes. If poor weather, an alternate live tour of the night sky will be held in the planetarium theater.; Free.

S p e c i a l E v e n t sS p e c i a l E v e n t sS p e c i a l E v e n t sS p e c i a l E v e n t s

Saturday, April 29, 20171-4:30 p.m.

8:30-10 p.m.

Nature Center& Observatory

Annual Astronomy Day - Displays et al. on the walkway leading to the Nature Center, 1-4:30 p.m.; Solar viewing 3-4 p.m. at the dam; Night viewing 8:30-10 p.m. at the observatory. All non-planetarium astronomy activities are

free.

July ?, 2017 6 p.m. ? Annual club picnic. BMACers and their families are most welcome to enjoy the evening along with a potluck dinner. Please bring a dish to share. You’ll need to bring your own chair and telescope to share the night sky.

Bays Mountain Astronomy Club853 Bays Mountain Park Road

Kingsport, TN 376501 (423) 229-9447

www.baysmountain.com

[email protected]

Annual Dues:

Dues are supplemented by the Bays Mountain Park Association and volunteerism by the club. As such, our dues can be kept at a very low cost.

$16 /person/year

$6 /additional family member

Note: if you are a Park Association member (which incurs an additional fee), then a 50% reduction in BMAC dues are applied.

The club’s website can be found here:

www.baysmountain.com/astronomy/astronomy-club/

Regular Contributors:

Brandon Stroupe

Brandon is the current chair of the club. He is a photographer for his home business,

Broader Horizons Photography and an avid astrophotographer. He has been a member

since 2007.

Robin Byrne

Robin has been writing the science history column since 1992 and was chair in 1997.

She is an Associate Professor of Astronomy & Physics at Northeast State

Community College (NSCC).

Jason Dorfman

Jason works as a planetarium creative and technical genius at Bays Mountain Park.

He has been a member since 2006.

Adam Thanz

Adam has been the Editor for all but a number of months since 1992. He is the

Planetarium Director at Bays Mountain Park as well as an astronomy adjunct for

NSCC.


http://www.baysmountain.com

http://www.baysmountain.com

mailto:[email protected]?subject=

mailto:[email protected]?subject=

http://www.baysmountain.com/astronomy/astronomy-club/

http://www.baysmountain.com/astronomy/astronomy-club/

Footnotes:1. The Rite of SpringOf the countless equinoxes Saturn has seen since the birth of the solar system, this one, captured here in a mosaic of light and dark, is the first witnessed up close by an emissary from Earth … none other than our faithful robotic explorer, Cassini.Seen from our planet, the view of Saturn’s rings during equinox is extremely foreshortened and limited. But in orbit around Saturn, Cassini had no such problems. From 20 degrees above the ring plane, Cassini’s wide angle camera shot 75 exposures in succession for this mosaic showing Saturn, its rings, and a few of its moons a day and a half after exact Saturn equinox, when the sun’s disk was exactly overhead at the planet’s equator.The novel illumination geometry that accompanies equinox lowers the sun’s angle to the ring plane, significantly darkens the rings, and causes out-of-plane structures to look anomalously bright and to cast shadows across the rings. These scenes are possible only during the few months before and after Saturn’s equinox which occurs only once in about 15 Earth years. Before and after equinox, Cassini’s cameras have spotted not only the predictable shadows of some of Saturn’s moons (see PIA11657), but also the shadows of newly revealed vertical structures in the rings themselves (see PIA11665).Also at equinox, the shadows of the planet’s expansive rings are compressed into a single, narrow band cast onto the planet as seen in this mosaic. (For an earlier view of the rings’ wide shadows draped high on the northern hemisphere, see PIA09793.)The images comprising the mosaic, taken over about eight hours, were extensively processed before being joined together. First, each was re-projected into the same viewing geometry and then digitally processed to make the image “joints” seamless and to remove lens flares, radially extended bright artifacts resulting from light being scattered within the camera optics.At this time so close to equinox, illumination of the rings by sunlight reflected off the planet vastly dominates any meager sunlight falling on the rings. Hence, the half of the rings on the left illuminated by planetshine is, before processing, much brighter than the half of the rings on the right. On the right, it is only the vertically extended parts of the rings that catch any substantial sunlight.With no enhancement, the rings would be essentially invisible in this mosaic. To improve their visibility, the dark (right) half of the rings has been brightened relative to the brighter (left) half by a factor of three, and then the whole ring system has been brightened by a factor of 20 relative to the planet. So the dark half of the rings is 60 times brighter, and the bright half 20 times brighter, than they would have appeared if the entire system, planet included, could have been captured in a single image.The moon Janus (179 kilometers, 111 miles across) is on the lower left of this image. Epimetheus (113 kilometers, 70 miles across) appears near the middle bottom. Pandora (81 kilometers, 50

miles across) orbits outside the rings on the right of the image. The small moon Atlas (30 kilometers, 19 miles across) orbits inside the thin F ring on the right of the image. The brightnesses of all the moons, relative to the planet, have been enhanced between 30 and 60 times to make them more easily visible. Other bright specks are background stars. Spokes -- ghostly radial markings on the B ring -- are visible on the right of the image.This view looks toward the northern side of the rings from about 20 degrees above the ring plane.The images were taken on Aug. 12, 2009, beginning about 1.25 days after exact equinox, using the red, green and blue spectral filters of the wide angle camera and were combined to create this natural color view. The images were obtained at a distance of approximately 847,000 kilometers (526,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 74 degrees. Image scale is 50 kilometers (31 miles) per pixel.The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.Image Credit: NASA/JPL/Space Science Institute

2. Duke on the Craters EdgeAstronaut Charles M. Duke Jr., Lunar Module pilot of the Apollo 16 mission, is photographed collecting lunar samples at Station no. 1 during the first Apollo 16 extravehicular activity at the Descartes landing site. This picture, looking eastward, was taken by Astronaut John W. Young, commander. Duke is standing at the rim of Plum crater, which is 40 meters in diameter and 10 meters deep. The parked Lunar Roving Vehicle can be seen in the left background.Image AS16-114-18423Creator/Photographer: NASA John W. Young

3. The Cat's Eye Nebula, one of the first planetary nebulae discovered, also has one of the most complex forms known to this kind of nebula. Eleven rings, or shells, of gas make up the Cat's Eye.Credit: NASA, ESA, HEIC, and The Hubble Heritage Team (STScI/AURA)Acknowledgment: R. Corradi (Isaac Newton Group of Telescopes, Spain) and Z. Tsvetanov (NASA)

4. Jupiter & Ganymede

Section 3

Footnotes



S e e F N 3

http://saturn.jpl.nasa.gov

http://saturn.jpl.nasa.gov

http://ciclops.org

http://ciclops.org

NASA's Hubble Space Telescope has caught Jupiter's moon Ganymede playing a game of "peek-a-boo." In this crisp Hubble image, Ganymede is shown just before it ducks behind the giant planet.Ganymede completes an orbit around Jupiter every seven days. Because Ganymede's orbit is tilted nearly edge-on to Earth, it routinely can be seen passing in front of and disappearing behind its giant host, only to reemerge later.Composed of rock and ice, Ganymede is the largest moon in our solar system. It is even larger than the planet Mercury. But Ganymede looks like a dirty snowball next to Jupiter, the largest planet in our solar system. Jupiter is so big that only part of its Southern Hemisphere can be seen in this image.Hubble's view is so sharp that astronomers can see features on Ganymede's surface, most notably the white impact crater, Tros, and its system of rays, bright streaks of material blasted from the crater. Tros and its ray system are roughly the width of Arizona.The image also shows Jupiter's Great Red Spot, the large eye-shaped feature at upper left. A storm the size of two Earths, the Great Red Spot has been raging for more than 300 years. Hubble's sharp view of the gas giant planet also reveals the texture of the clouds in the Jovian atmosphere as well as various other storms and vortices.Astronomers use these images to study Jupiter's upper atmosphere. As Ganymede passes behind the giant planet, it reflects sunlight, which then passes through Jupiter's atmosphere. Imprinted on that light is information about the gas giant's atmosphere, which yields clues about the properties of Jupiter's high-altitude haze above the cloud tops.This color image was made from three images taken on April 9, 2007, with the Wide Field Planetary Camera 2 in red, green, and blue filters. The image shows Jupiter and Ganymede in close to natural colors.Credit: NASA, ESA, and E. Karkoschka (University of Arizona)

5. 47 TucanaeIn the first attempt to systematically search for "extrasolar" planets far beyond our local stellar neighborhood, astronomers probed the heart of a distant globular star cluster and were surprised to come up with a score of "zero".To the fascination and puzzlement of planet-searching astronomers, the results offer a sobering counterpoint to the flurry of planet discoveries announced over the previous months."This could be the first tantalizing evidence that conditions for planet formation and evolution may be fundamentally different elsewhere in the galaxy," says Mario Livio of the Space Telescope Science Institute (STScI) in Baltimore, MD.The bold and innovative observation pushed NASA Hubble Space Telescope's capabilities to its limits, simultaneously scanning for small changes in the light from 35,000 stars in the globular star cluster 47 Tucanae, located 15,000 light-years (4 kiloparsecs) away in the southern constellation Tucana.Hubble researchers caution that the finding must be tempered by the fact that some astronomers always considered the ancient globular cluster an unlikely abode for planets for a variety of reasons. Specifically, the cluster has a deficiency of heavier elements that may be needed for building planets. If this is the case, then planets may have formed later in the universe's evolution, when stars were richer in heavier elements. Correspondingly, life as we know it may have appeared later rather than sooner in the universe.Another caveat is that Hubble searched for a specific type of planet called a "hot Jupiter," which is considered an oddball among some planet experts. The results do not rule out the possibility that 47 Tucanae could contain normal solar systems like ours, which Hubble could not have detected.

But even if that's the case, the "null" result implies there is still something fundamentally different between the way planets are made in our own neighborhood and how they are made in the cluster.Hubble couldn't directly view the planets, but instead employed a powerful search technique where the telescope measures the slight dimming of a star due to the passage of a planet in front of it, an event called a transit. The planet would have to be a bit larger than Jupiter to block enough light — about one percent — to be measurable by Hubble; Earth-like planets are too small.However, an outside observer would have to watch our Sun for as long as 12 years before ever having a chance of seeing Jupiter briefly transit the Sun's face. The Hubble observation was capable of only catching those planetary transits that happen every few days. This would happen if the planet were in an orbit less than 1/20 Earth's distance from the Sun, placing it even closer to the star than the scorched planet Mercury — hence the name "hot Jupiter."Why expect to find such a weird planet in the first place?Based on radial-velocity surveys from ground-based telescopes, which measure the slight wobble in a star due to the small tug of an unseen companion, astronomers have found nine hot Jupiters in our local stellar neighborhood. Statistically this means one percent of all stars should have such planets. It's estimated that the orbits of 10 percent of these planets are tilted edge-on to Earth and so transit the face of their star.In 1999, the first observation of a transiting planet was made by ground-based telescopes. The planet, with a 3.5-day period, had previously been detected by radial-velocity surveys, but this was a unique, independent confirmation. In a separate program to study a planet in these revealing circumstances, Ron Gilliland (STScI) and lead investigator Tim Brown (National Center for Atmospheric Research, Boulder, CO) demonstrated Hubble's exquisite ability to do precise photometry — the measurement of brightness and brightness changes in a star's light — by also looking at the planet. The Hubble data were so good they could look for evidence of rings or Earth-sized moons, if they existed.But to discover new planets by transits, Gilliland had to crowd a lot of stars into Hubble's narrow field of view. The ideal target was the magnificent southern globular star cluster 47 Tucanae, one of the closest clusters to Earth. Within a single Hubble picture Gilliland could observe 35,000 stars at once. Like making a time-lapse movie, he had to take sequential snapshots of the cluster, looking for a telltale dimming of a star and recording any light curve that would be the true signature of a planet.Based on statistics from a sampling of planets in our local stellar neighborhood, Gilliland and his co-investigators reasoned that 1 out of 1,000 stars in the globular cluster should have planets that transit once every few days. They predicted that Hubble should discover 17 hot Jupiter-class planets.To catch a planet in a several-day orbit, Gilliland had Hubble's "eagle eye" trained on the cluster for eight consecutive days. The result was the most data-intensive observation ever done by Hubble. STScI archived over 1,300 exposures during the observation. Gilliland and Brown sifted through the results and came up with 100 variable stars, some of them eclipsing binaries where the companion is a star and not a planet. But none of them had the characteristic light curve that would be the signature of an extrasolar planet.There are a variety of reasons the globular cluster environment may inhibit planet formation. 47 Tucanae is old and so is deficient in the heavier elements, which were formed later in the universe through the nucleosynthesis of heavier elements in the cores of first-generation stars. Planet surveys show that within 100 light-years of the Sun, heavy-element-rich stars are far more likely to harbor a hot Jupiter than heavy-element-poor stars. However, this is a chicken and egg puzzle because some theoreticians say that the heavy-element composition of a star may be enhanced after if it makes Jupiter-like planets and then swallows them as the planet orbit spirals into the star.


The stars are so tightly compacted in the core of the cluster – being separated by 1/100th the distance between our Sun and the next nearest star — that gravitational tidal effects may strip nascent planets from their parent stars. Also, the high stellar density could disturb the subsequent migration of the planet inward, which parks the hot Jupiters close to the star.Another possibility is that a torrent of ultraviolet light from the earliest and biggest stars, which formed in the cluster billions of years ago may have boiled away fragile embryonic dust disks out of which planets would have formed.These results will be published in The Astrophysical Journal Letters in December. Follow-up observations are needed to determine whether it is the initial conditions associated with planet birth or subsequent influences on evolution in this heavy-element-poor, crowded environment that led to an absence of planets.Credits for Hubble image: NASA and Ron Gilliland (Space Telescope Science Institute)

6. Space Place is a fantastic source of scientific educational materials for children of all ages. Visit them at:http://spaceplace.nasa.gov

7. NGC 3982Though the universe is chock full of spiral-shaped galaxies, no two look exactly the same. This face-on spiral galaxy, called NGC 3982, is striking for its rich tapestry of star birth, along with its winding arms. The arms are lined with pink star-forming regions of glowing hydrogen, newborn blue star clusters, and obscuring dust lanes that provide the raw material for future generations of stars. The bright nucleus is home to an older population of stars, which grow ever more densely packed toward the center.NGC 3982 is located about 68 million light-years away in the constellation Ursa Major. The galaxy spans about 30,000 light-years, one-third of the size of our Milky Way galaxy. This color image is composed of exposures taken by the Hubble Space Telescope's Wide Field Planetary Camera 2 (WFPC2), the Advanced Camera for Surveys (ACS), and the Wide Field Camera 3 (WFC3). The observations were taken between March 2000 and August 2009. The rich color range comes from the fact that the galaxy was photographed invisible and near-infrared light. Also used was a filter that isolates hydrogen emission that emanates from bright star-forming regions dotting the spiral arms.Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)Acknowledgment: A. Riess (STScI)

8. Ball and Raytheon technicians integrate the VIIRS Optical and Electrical Modules onto the JPSS-1 spacecraft in 2015. The spacecraft will be ready for launch later this year. Image Credit: Ball Aerospace & Technologies Corp.


The Monthly Newsletter of the Bays Mountain Astronomy Club...stars as Boötes and Virgo....

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Transcript of The Monthly Newsletter of the Bays Mountain Astronomy Club...stars as Boötes and Virgo....