This is the Saint Louis Science Center’s NIGHT SKY UPDATE for the week of Monday, May 20.  All times are given as local St. Louis time (Central Daylight Time).  For definitions of terminology used in the night sky update, click the highlighted text.

Information updated weekly or as needed.

Join us for our next star party, Friday, June 7, 2013 held in association with the St. Louis Astronomical Society. For details, see the information at the bottom of this page.

The Sun and the Moon

Sunrise is at 5:45 a.m. on Monday, May 20 and sunset is at 8:11 p.m. providing us with over 14 hours of daylight.  Even after sunset, the light from the Sun will still illuminate our sky for nearly two hours.  This period of time is called twilight, which ends around 10:00 p.m. this week.  For those with a sun dial, solar transit or local noon occurs around 12:58 p.m. this week.

Moonrise for Monday, May 20 is at 3:21 p.m. and moonset is at 3:09 a.m. on the following day.  On Monday, May 20 the Moon will be exhibiting a waxing gibbous phase with roughly 75% of the lunar disk illuminated.  Full moon occurs on Friday, May 24 at 11:26 p.m.  May’s full moon is called the Full Flower Moon.

International Space Station (ISS) Observing

ISS passes over St. Louis for the next two weeks starting Monday, May 20 are all early morning passes.  The best passes come on the mornings of May 21, 22 and 24. 

Catch ISS flying over St. Louis in the morning hours the week of Monday, May 20. 

Magnitude (Mag): The Measure of brightness for a celestial object.  The lower the value is, the brighter the object will be.

Altitude (Alt):  The angle of a celestial object measured upwards from the observer’s horizon.

Azimuth (Az):  The direction of a celestial object, measured clockwise from an observer’s location with north being 0°, east being 90°, south being 180° and west being 270°.

For information about ISS flyovers and other visible satellites, visit www.heavens-above.com

Detailed information regarding all unmanned exploration of our universe, missions past, present, and planned, can be found at Jet Propulsion Laboratories:

http://www.jpl.nasa.gov/

The Planets Visible Without A Telescope

Mercury

The elusive planet Mercury is once again with us in the early evening.  You only have a short time to catch this planet as it sets at 9:03 p.m.  Mercury will continue to climb higher in the western skies just after sunset until June 12 when it reaches maximum eastern elongation.  On the 24^th of May, Mercury and Venus will reach conjunction.  The two planets will be less than two degrees apart. 

Venus

The brightest planet in the sky is starting another evening apparition becoming visible about 20 minutes after sunset.  For the time being it may be difficult to spot since it will be low to the horizon and any trees or buildings west of you will likely obscure it from view.  As May progresses Venus will climb higher in the sky and will be joined by Jupiter and Mercury for a planetary conjunction at the end of the month.  Venus is currently seen in the constellation Taurus and will set by 9:14 p.m. 

Jupiter

The planet Jupiter will be visible shortly after sunset and sets around 9:47 p.m.  Grab a pair of binoculars and see how many of the Galilean moons you can see.  Depending on when you look you should be able to see all four; Io, Europa, Ganymede and Callisto.  As you watch them sketch their locations relative to Jupiter and you will be following in the footsteps of Galileo. 

Saturn

Look for the ringed planet shortly after sunset low in the southeast.  Currently Saturn is found in the constellation Virgo just to the east of the bright star Spica.  Saturn will set by 4:51 a.m. 

Planetary Conjunction: Mercury, Venus and Jupiter

If you have never seen a planetary conjunction now is your chance.  Starting on May 24^th Mercury and Venus will be seen close together in the sky.  Two days later on the May 26, Jupiter will join the others.  These three planets will be less than 2.5 degrees apart.  This will be your last chance to see three planets this close together until 2026.  The three planets will stay close together until June 7^th when they start to separate once again.  From May 24 – 29 these three planets will be in conjunction with each other on various days.  A conjunction occurs when two astronomical objects share the same right ascension.  Listed below are the dates of conjunctions associated with this grouping of three planets. 

May 24 – Mercury and Venus

May 26 – Mercury and Jupiter

May 28 – Venus and Jupiter

To learn more follow the link bellow.    

http://www.skyandtelescope.com/observing/highlights/The-May-June-2013-Planet-Dance-192020551.html

Constellation of the Month

Each month we will highlight one constellation and some of the objects that can be found within the boundaries of that constellation.  At the start of the month we will list only a few of these objects and each week we will add another to the list.  Some objects will be visible to the unaided eye and some may require a telescope.  Many of the objects listed will require a map of the sky to find or may require repeat observations to notice various properties.  Links to star charts and other information that will be useful in identifying the objects listed will be given at the end of each week’s section. 

This month our constellation is Ursa Minor.  Also known as the Little Bear, this constellation can be found in the circumpolar sky.  The term circumpolar indicates that the stars which make up the constellation never really rise or set but rather circle around the North Star.  Due to its location in the circumpolar sky, Ursa Minor is visible all year long.  The name Ursa Minor comes from the ancient Greek interpretation of this star pattern.  The story involves a Nymph of the Moon goddess Artemis named Callisto.  She was wooed by Zeus and gave birth to a son named Arcas.  Fearing the anger of Artemis and his wife, Zeus turned Callisto into a bear.  One day her son was hunting and came across a great bear who unbeknownst to him was his mother.  As he knocked his arrow and took aim, Zeus intervened and turned Arcas into a bear.  Now a bear, Arcas recognized his mother and the two were then placed into the sky together safe from hunters and the ire of Hera.  This story led to the formation of Ursa Minor (Arcas) and Ursa Major (Callisto).

To find Ursa Minor locate the Big Dipper high in the northern skies.  Using the two stars at the end of the dipper’s bowl, trace a straight line above the bowl until you find Polaris.  This will be the brightest star in Ursa Minor.  Once you have found Polaris use the star chart linked below to find the rest of the stars of Ursa Minor. 

http://www.iau.org/static/public/constellations/gif/UMI.gif

Object of the week for April 29 is the Little Dipper.  Even though the Little Dipper is well known to most, it is not nearly as easy to find as most would think.  Frequently people think that the star cluster M45 (Pleiades) is the Little Dipper.  It does indeed look like a small spoon but it is never seen in the north.  The common method used to find the Little Dipper is to use the last two stars in the bowl of the Big Dipper.  Just like was mentioned above, follow a straight line above the Big Dipper’s bowl and this will take you to the North Star.  The North Star is the last star in the Little Dipper’s handle.

The little dipper also serves as a good lesson in light pollution.  In cities most of the stars in the Little Dipper are very difficult to see due to light pollution drowning out their light.  The more stars you can see in the Little Dipper, the better your viewing conditions will be.  It is also important to mention that if you leave North America, it is no longer called the Little Dipper.  Both the Big and Little Dippers are not constellations but rather are asterisms.  These are informal groupings of stars as opposed to the formal groupings we call constellations.

Lastly, the Little Dipper was chosen for our first object in May as it will serve as our reference point for the rest of the month.  Most of the objects we will cover in May are visible in just a pair of binoculars but they will be considerately more difficult to find.  It is important to have a strong reference point to base our explorations from.  

Object of the week for May 6 is an asterism called the Engagement Ring.  First off we should explain what an asterism is.  Asterisms are the informal patterns of stars as opposed to the constellations which are the formal groupings of stars astronomers use to organize the sky.  Both the Big and Little Dippers are asterisms.  The Engagement Ring asterism is found near the North Star.  To find the North Star follow the instructions above.  Once you have found the North Star grab a pair of binoculars and scan the area just below it and you will see a faint ring of 7^th to 8^th magnitude stars.  These stars make the ring’s band and the North Star represents the Diamond in the ring.  While you are looking at the North Star if available grab a telescope and try to split it into two stars.  Like most other stars, Polaris is a double star.  It will not be an easy split but it is doable in small telescopes at higher powers.

Object of the week for May 13 is a star called V UMi.  This star is a semi regular variable star that has a peak magnitude of 7.06 and minima of 8.7.  The cause of the brightness shift in this star is an internal pulsation that causes that star to flare in brightness roughly every 73 days.  Due to it being a semi regular variable, V UMi’s period of variability can change.  It is an M-class red giant star indicating that its internal pulsations cause the tenuous outer atmosphere of the star swell and becomes more luminous.

Since V UMi is a circumpolar star it can be monitored year round making it a great option for learning how to observe variable stars with longer periods of variability.  To find V UMi look for the star Eta Ursae Minoris.  This star is also called 21 UMi and is the bottom star on the inner edge of the Little Dipper’s bowl.  From here look about 4 degrees to the west and you will find V UMi.  To identify this star you will need to pay close attention to the fainter stars in the field of view.  To help with this there will be multiple links to maps that represent the star field around V UMi.  If you enjoy hunting down this variable star it is one of 153 variable stars on AAVSO’s list of binocular variables.  For those interested in finding more of these binocular variables the AAVSO list will also be posted.

http://www.iau.org/static/public/constellations/pdf/UMI.pdf

http://www.aavso.org/vsp/chart

http://www.aavso.org/aavso-binocular-program

Object for the week of May 20 is a concept more than an object.  We are all taught to find the North Star if we wanted to locate the direction north.  To do this you just follow the last two stars in the bowl of the Big Dipper above the bowl and you will find the North Star.  The star we call the North Star is Polaris and it is found at the end of the Little Dipper’s handle.  It may come as a surprise that this star will not always be the North Star nor has it always been.  Due to a motion called precession, the Earth’s poles change their orientation relative to the stars.  This motion can be perceived as a wobble much like a top when its axial rotation slows down.  The cause of precession is tidal forces induced by the Moon, Sun and to a lesser extent the other planets.  Earth takes roughly 26,000 years to make one precession cycle.

So what are some other stars that have been or will be North Stars?  Around the year 3000 CE, a star called Gamma Cephei will be closest to the north celestial pole.  In 14,000 years the bright star Vega will be closest to the north celestial pole.  In the past, a star in the constellation Draco, called Thuban, was the North Star.  Thuban was the North Star about 6000 years ago when the ancient Egyptians were building the great pyramids.  The ancient Egyptians developed complex cosmologies and even cultural traditions based on observing Thuban and other stars.  One common use was the telling of time.  Based on the position of the stars around the North Star, they knew the time of year.  They also recorded time with it.  Many of the funeral sarcophagi were adorned with star positions relative to their death.  Ancient Egyptian astronomy is quite fascinating and in part is still in use today.  Thanks to the ancient Egyptians we have a day divided into 24 hours. 

To Find Thuban and the other North Stars follow the links below.

Thuban

Gamma Cephei

Vega

NASA Mission of the Month

Each month we will be celebrating a NASA mission of the month.  This month’s mission is the historic Mercury Program.  The Mercury program ran from 1958 to 1963.  It was NASA’s first foray into manned space flight.  It entailed six manned missions and a number of other test flights that included sending a Rhesus Monkey and two Chimpanzees into space.  It was the program that proved we could put a human in space and have them orbit the Earth.  The Mercury missions were one person flights that launched aboard the Redstone and Atlas rockets.  To learn more about this historic program follow the link below.

http://www.nasa.gov/centers/kennedy/about/history/mercury7.html

50^th Anniversary of the James S. McDonnell Planetarium

2013 marks the 50^th anniversary of the James S. McDonnell Planetarium.  There are a number of events planned for the year that will celebrate the 50^th anniversary.  For more information about the planetarium and the 50^th anniversary, visit www.slsc.org

Our next Star Party will be held on Friday, June 7, 2013, from dusk until 10 p.m.
Weather permitting, the St. Louis Astronomical Society and the Science Center will set up a number of telescopes outdoors and be on-hand to answer your questions.  Telescope viewing begins at 8:00 p.m.  Regardless of the weather on May 3, join us indoors in our Planetarium Theater for “The Sky Tonight”.  Showtime is at 7 p.m. (Please note this time changed from 8:00 p.m.  to 7:00 p.m. due to Laserium shows starting a 8:30 p.m.)  

This free, indoor star program will introduce you to the current night sky, the planets, and the seasonal constellations. Doors open 15 minutes before show time. Shows begins at 8 p.m. Sorry, no late admissions due to safety issues in the darkened theater.

The St. Louis Astronomical Society hosts the monthly Star Parties at the Science Center which are held on the first Friday of each month. Our Monthly Star Parties are open to the public and free of charge.  For more information about the St. Louis Astronomical Society visit their website at www.slasonline.org

For some adults visiting as part of an adult group, exploring the Science Center amidst a sea of enthusiastic kids can be a bit overwhelming. Fortunately, we truly do having something for all ages to enjoy. Next time you load up the car for a trip to the Science Center with your more seasoned friends, consider checking out my top 5 recommendations for adults.

Inside the StarBay of the James S. McDonnell Planetarium

1)      Live Sky Tonight Show: Planetarium Shows make for a very memorable experience and Live Sky Tonight happens to be my favorite show and my favorite choice for adults! The show features what is currently visible in the night sky over St. Louis including constellations, planets, the current Moon phase and any other special astronomical events taking place. If you have never experienced a true dark sky, you MUST see this show. The “ahs” are audible when the show presenter transforms the dome from what would be visible from the city to what would be visible in a perfect dark night sky. Planetarium Shows are $5 for adults, $4 for seniors and FREE for Members.

2)      Life Science Lab Activity Benches: The activity benches in the Life Science Lab sounded like a great idea…for kids…when I first learned about them. You are required to don a lab coat, safety glasses and gloves in order to complete various experiments that range from DNA extraction to determining blood types. Fortunately, my colleagues urged me to check out the activity benches for myself and it turns out that I really enjoyed the experience! I was able to take part in experiments that I never even had the opportunity to do way back when in my school days. Still not sure about the Life Science Lab activity benches? There may be kids around, but you don’t have to share your bench with kids. No fear of interference here! The Life Science Lab is one of our FREE attractions.

Pictures don't even do the OMNIMAX Theater experience justice.

3)      OMNIMAX® Theater: Our OMNIMAX Theater features a 5 story domed screen. If you have never taken in a beautiful IMAX® film in a domed theater, this recommendation will be well worth your time. The picture consumes the entire screen which appears to wrap around you. I haven’t seen a film come through the Science Center that I haven’t liked yet, so you are sure to enjoy whichever you choose! This summer we are screening Flight of the Butterflies, Air Racers and Mummies: Secrets of the Pharaohs. Tip: Try to sit closer to the back and toward the middle of the theater! OMNIMAX Shows are $9 for adults, $8 for seniors and FREE with vouchers for Members.

4)      Human Adventure: Human Adventure is one of those time-tested and proven attractions for us. The entire area is dedicated to your senses and memory and it is highly interactive. This is quite possibly the gallery most enjoyed by adult visitors (at least that is my opinion based on personal observations of the space). When the exhibits went away during the construction of Boeing Hall, there was an outpouring of visitors asking us to bring their beloved Human Adventure gallery back. And we did! Visitors continue to spend a lot of time in this area. Human Adventure is one of our FREE attractions.

Playing with liquid nitrogen during an Ira & Judy Gall Amazing Science Demonstration at CenterStage.

5)      Amazing Science Demonstrations: Ira & Judy Gall Amazing Science Demonstrations are live shows that take place at CenterStage. Science Center staff members mesmerize you with simple yet high impact science experiments that often involve fire, electricity and even liquid nitrogen. So…kiddos are usually in attendance at these demonstrations, but adults tend to enjoy them too and as an adult you will definitely walk away having learned something new. Tip: If being amongst the kids is too much to handle, you can take in a show from the overlook on the First Floor! Amazing Science Demonstrations are FREE for the public.

Still not comfortable with the idea of braving the Science Center amongst packs of rabid children? Try visiting the Science Center for special adult programming after hours! The atmosphere of the Science Center completely changes at night, so it will definitely be a new experience for you and your adult crew.

On the first Friday of every month we stay open late for an event called First Friday (…I know). The night usually entails programming that dives deeper into the science behind favorite science fiction topics. In addition to the special programming, nearly the entire Science Center is open, so you can explore our various attractions sans kids during our First Friday extended hours. In full disclosure, First Fridays are designed for adults, but families are welcome. You can expect the number of kids to be drastically reduced compared to daytime numbers. First Fridays are FREE and you can take advantage of special First Friday pricing for our paid venues.

If you are looking for no kids whatsoever, you may want to check out Cheap Date Night. Several times a year, we turn the James S. McDonnell Planetarium over for adults to rule the roost! A kid free experience is guaranteed at Cheap Date Night because you must be 21 or older to get in on the fun. Cheap Date Night usually consists of a special Live Sky Tonight show designed around a major astronomical event followed by a classic scifi movie. At our next Cheap Date Night on August 10th, we will simulate the Perseid Meteor Shower! Tip: Cheap Date Night’s sell out in advance! Purchase your tickets before the big day if you want to make sure you have a seat. Tickets are $10 in advance and $15 at the door.

I want to part with some final tips for you to make the most of your experience. Try visiting later in the day. Usually 2 p.m. or later is a safe bet for missing the high traffic “kid time.” If you are visiting in the morning, try perking up your outlook with a good strong latte from our café. Stroll by the Dana Brown Fossil Prep Lab to see if any of the workers or volunteers are preparing real dinosaur fossils. Discussing how they go about preparing the fossils can be fascinating! Also, check out the return of the LASERIUM® laser shows while we still have them during the 50^th anniversary year of the James S. McDonnell Planetarium. Finally, do consider joining us for our after hour events. The availability of alcohol is guaranteed for First Fridays and Cheap Date Nights, so make a deal with your designated driver in advance.

Don’t see your favorite activity listed here? Share your favorite Science Center must-dos for adults in the comment section below!

Written by Staci, Communication

Five Local Teachers Recognized For Excellence In Science and Mathematics Education

Joseph Bartin, 2013 Loeb Prize Winner

ST. LOUIS – Joseph Bartin, physics and astronomy teacher at Kirkwood High School, says he became a teacher 15 years ago because he wanted to do work that made a difference.  “I remain a teacher because I am inspired by the work, wonder and curiosity of the students with whom I spend my time.” 

That viewpoint is one of many reasons why Bartin won the 2013 Saint Louis Science Center and Carol B. and Jerome T. Loeb Prize for Excellence in Teaching Science & Mathematics. Bartin was selected from a field of five finalists and presented his award at an awards ceremony at the Saint Louis Science Center.

Loeb Prize Winners honored in 2013. Left: Carol Valenta, Chief Scientific Officer; Kristine Becker, Finalist; Karen Torretta, Finalist; Susan Doering, Runner-up; Erin King, Finalist; Joseph Bartin, Winner; Carol B. Loeb, Loeb Prize Donor

Susan Doering of St. Francis of Assisi School in Oakville was honored with a second place award. The other three finalists were Kristine Becker of Halls Ferry Elementary School, Erin King of McCluer North High School, and Karen Torretta of Oakville High School.  All five finalists received cash awards and were cheered on by their students at today’s ceremony.  As the winner, Bartin also received a complimentary trip to one of the Science Center’s 2013 Science Adventure Travel destinations.

The Loeb Prize, which rewards teachers who significantly enhance their students' performances in the areas of science and mathematics, was established in 1995 and endowed in 2002 by a generous gift from Carol B. and Jerome T. Loeb. It is one of the many ways in which the Loeb family and the Science Center demonstrate their commitment to advance public appreciation for teachers' efforts.

“Each year we interview so many exceptionally talented teachers and it is very difficult to choose only five finalists,” said Mrs. Loeb. ”I am grateful to have the opportunity to recognize these teachers for the work they do to transform students into leaders of tomorrow.”

The late Mr. Loeb worked for The May Department Stores Company, retiring as chairman of the board. He was chairman of the Science Center's Board of Commissioners and a member of the Board of Trustees. Mrs. Loeb, a math teacher for 50 years, currently serves on the Science Center's Board of Trustees.

“The Loeb Prize is a very significant way to honor some of the outstanding teachers in the region,” said Carol Valenta, Chief Scientific Officer for the Science Center. “Recognition of these teachers will go a long way in ensuring teachers are held in high regard in the St. Louis community.”

The teacher-student relationship is important to Bartin. Last summer, many of his students lost a close friend under tragic circumstances, so Bartin began the school year quietly, “letting them know that, before curriculum and class activities, I was there to help and support them.”  Bartin said he forged relationships with his students stronger than ever.  “I feel this year like we are sharing an experience, not simply interacting around a curriculum.”

The 2013 finalists for the Loeb Prize are:

• Winner: Joseph Bartin, Kirkwood High School
• Second Place: Susan Doering, St. Francis of Assisi School
• Finalist: Kristine Becker, Halls Ferry Elementary School
• Finalist: Erin King, McCluer North High School
• Finalist: Karen Torretta, Oakville High School

View the award ceremony program.

Written by Margie, Communications

Newswise — WASHINGTON – Fossil remains found by a George Washington University biologist in northwestern China have been identified as a new species of small theropod, or meat-eating, dinosaur.

The discovery was made by James Clark, the Ronald B. Weintraub Professor of Biology, in the Department of Biological Sciences of GW’s Columbian College of Arts and Sciences. Dr. Clark, along with his then doctoral student Jonah Choiniere and a team of international researchers, found the dinosaur specimen in a remote region of Xinjiang in China in 2006.

Fossil of Aorun zhaoi skull found in 2006 in Xinjiang, China. CREDIT: Journal of Systematic Palaeontology, May-2013

Fossil remains found by a George Washington University biologist in northwestern China have been identified as a new species of small theropod, or meat-eating, dinosaur. CREDIT: Journal of Systematic Palaeontology, May-2013

In a research paper published in the Journal of Systematic Palaeontology, Drs. Clark and Choiniere explain recovering the skull, mandible and partial skeleton of the dinosaur. The new theropod was an estimated 1 meter or just over 3 feet long and probably weighed about 3 pounds.

“All that was exposed on the surface was a bit of the leg,” said Dr. Clark. “We were pleasantly surprised to find a skull buried in the rock too.”

The dinosaur is named Aorun zhaoi, after the Dragon King in the Chinese epic tale Journey to the West. It wasn’t necessarily a small dinosaur species, though, because Aorun was still a youngster when it became a fossil.

“We were able to look at microscopic details of Aorun’s bones and they showed that the animal was less than a year old when it died on the banks of a stream,” said Dr. Choiniere.

Dr. Choiniere, now a senior researcher at the Evolutionary Studies Institute at the University of the Witwatersrand in Johannesburg, South Africa, was a doctoral student in Biological Studies at GW when the discovery was made. He was also a Kalbfleisch Fellow and Gerstner Scholar at the American Museum of Natural History.

Aorun lived more than 161 million years ago, in the earliest part of the Late Jurassic Period. Its small, numerous teeth suggest that it would have eaten prey like lizards and small relatives of today’s mammals and crocodilians.

This is the fifth new theropod discovered at the Wucaiwan locality by the team, co-led by Dr. Clark and Dr. Xu Xing of the Chinese Academy of Sciences.

This research was funded by the National Science Foundation Division of Earth Sciences and the Chinese National Natural Science Foundation.

The Journal of Systematic Palaeontology is published on behalf of the National History Museum in London. The journal publishes papers which use systematics in ways that significantly advance the understanding of palaeogeography, palaeobiology, functional morphology, palaeoecology, biostratigraphy or phylogenetic relationships, as well as papers describing new or poorly understood fossil faunas and floras. The new paper can be accessed for a short time here:

The Columbian College
Established in 1821 in the heart of the nation’s capital, The George Washington University Columbian College of Arts and Sciences is the largest of GW’s academic units. It encompasses the School of Media and Public Affairs, the Trachtenberg School of Public Policy and Public Administration and more than 40 departments and programs for undergraduate, graduate and professional studies. The Columbian College provides the foundation for GW’s commitment to the liberal arts and a broad education for all students. An internationally recognized faculty and active partnerships with prestigious research institutions place Columbian College at the forefront in advancing policy, enhancing culture and transforming lives through research and discovery.

George Washington University
In the heart of the nation's capital with additional programs in Virginia, the George Washington University was created by an Act of Congress in 1821. Today, GW is the largest institution of higher education in the District of Columbia. The university offers comprehensive programs of undergraduate and graduate liberal arts study, as well as degree programs in medicine, public health, law, engineering, education, business and international affairs. Each year, GW enrolls a diverse population of undergraduate, graduate and professional students from all 50 states, the District of Columbia, and more than 130 countries.

View the original post.

We have another fun and exciting science experiment for any at-home scientist. It's chromatography! When you are finished you will have a fun art and science project.

First you'll need to take your scissors and trim down the coffee filter. You are also going to make a slit in the middle. Then you are going to decorate the filter with your marker. After that push the paper towel through. Finally place the coffee filter on the cup and watch!

What do you see?!

Try experimenting with this! What happens if you use a different color like purple? What happens if you use a different type like a wet erase marker? Does anything change?

Alright so what is happening? Chromatography is the science of seperating chemicals in a solvent. In this chromatography experiment the different colors are our chemicals and the water is our solvent.

Water molecules are actually very sticky and they like to stick together, scientist call this cohesion. They are also sticking to the paper towel, scientist call this adhesion. The sticky water molecules are travelling up the paper towel and spreading out through the coffee filter. Once it touches the marker the ink is spread out into all the different colors that make it up.

This is the Saint Louis Science Center’s NIGHT SKY UPDATE for the week of Monday, April 8.  All times are given as local St. Louis time (Central Daylight Time).  For definitions of terminology used in the night sky update, click the highlighted text.

Information updated weekly or as needed.

Join us for our next star party, Friday, May 3, 2013 held in association with the St. Louis Astronomical Society. For details, see the information at the bottom of this page.

The Sun and the Moon

Sunrise is at 6:35 a.m. on Monday, April 8 and sunset is at 7:31 p.m. providing us with nearly 13 hours of daylight.  Even after sunset, the light from the Sun will still illuminate our sky for roughly 1.5 hours.  This period of time is called twilight, which ends around 9:05 p.m. this week.  Solar transit or local noon occurs around 1:04 this week.

Moonrise for Monday, April 8 is at 5:24 a.m. and moonset is at 6:07 p.m.  On Monday, April 1 the Moon will be exhibiting a waning crescent phase with roughly 3% of the lunar disk illuminated.  New moon occurs on Wednesday, April 10.  

International Space Station (ISS) Observing

Visible passes of ISS over St. Louis for the next two weeks starting the week of Monday, April 8 are all evening passes.  For this two week period the best passes occur the evenings of April 8 and 10.  For more detailed information regarding these and other passes click the red links in the table.

Catch ISS flying over St. Louis in the morning hours during the week of Monday, April 8.

Magnitude (Mag): The Measure of brightness for a celestial object.  The lower the value is, the brighter the object will be.

Altitude (Alt):  The angle of a celestial object measured upwards from the observer’s horizon.

Azimuth (Az):  The direction of a celestial object, measured clockwise from an observer’s location with north being 0°, east being 90°, south being 180° and west being 270°.

For information about ISS flyovers and other visible satellites, visit www.heavens-above.com

Detailed information regarding all unmanned exploration of our universe, missions past, present, and planned, can be found at Jet Propulsion Laboratories:

http://www.jpl.nasa.gov/

The Planets Visible Without A Telescope

Jupiter

The planet Jupiter will be visible shortly after sunset and sets around 11:55 p.m.  Grab a pair of binoculars and see how many of the Galilean moons you can see.  Depending on when you look you should be able to see all four; Io, Europa, Ganymede and Callisto.  As you watch them sketch their locations relative to Jupiter and you will be following in the footsteps of Galileo.  While looking at Jupiter see if you can spot the stars Kappa and Upsilon Tauri just to the right of the planet.  Both of these stars are multiple star systems with Kappa being two stars and Upsilon being three.  Both systems are members of the V-shaped star cluster called the Hyades just below Jupiter.    

Saturn

Look for the ringed planet shortly after it rises around 9:06 p.m. this week.  Currently Saturn is found in the constellation Libra just to the west of the bright stars Zubeneschamali and Zubenalgenubi.  Opposition for Saturn occurs on April 28, 2013.  As we approach this date Saturn will continue to brighten and be seen early each night.  Once opposition occurs Saturn will be visible shortly after sunset.

2013 Year of the Comets?

In 2013 we may be treated to two spectacular comets.  These comets are called C/2011 L4 PANSTARRS and C/2012 S1 ISON.  Comets are named after whom or what discovers them and in both cases they were discovered by sky surveys.  The first comet we will see this year is C/2011 L4 PANSTARRS.  This comet is a long period comet with a near parabolic orbit that will likely not return to our skies for thousands to millions of years.  It reaches it closest point to the Earth (1.1 AU) on March 5, 2013 and its closest point to the Sun (0.3 AU, perihelion) March 10, 2013.  It will be visible throughout March and will be at its brightest on March 8-12.  Its greatest northern declination occurs on May 28, 2013 when it reaches a declination of +85.2 degrees.  Original predictions for peak brightness were -1 magnitude but have been downgraded 2 or 3 magnitude.  Even being a bit fainter then originally predicted, it should still be bright enough to be seen to the unaided eye.  

To find C/2011 L4 PANSTARRS, look low to the west starting 30 minutes after sunset on March 8.  Unfortunately it will be below 10 degrees up for the days it will be at its brightest.  If you have any trees or buildings west of your viewing location you will likely have issues finding the comet.  If this is the case look for a large parking lot near by that is open to the western skies.  Such places would be grocery stores, shopping malls, parks or anywhere with a large lot.  Be aware though that not all parks are open after sunset and some businesses may not want you on their lots.  If you plan to try and spot the comet with a telescope or plan to bring friends be sure to call ahead and check to make sure it is ok with the powers that be.  Links below have use articles or images pertaining to C/2011 L4 PANSTARRS.

http://www.skyandtelescope.com/observing/highlights/194257261.html

http://www.skyandtelescope.com/observing/highlights/185665152.html

http://spaceweather.com/

PANSTARRS Update Monday, March 18, 2013

So far Comet C/2011 L4 PANSTARRS has remained elusive to the unaided eye.  It is however easy to see through binoculars provided you know where to look.  Your best bet will be to go outside around 7:30 p.m. and locate west.  Start scanning the sky about 10 degrees north of west and 13 degrees above the horizon.  By 8:00 p.m. it will be roughly 7 degrees above the horizon.  You are looking for a bright coma with a distinct but short tail. 

http://www.skyandtelescope.com/observing/highlights/Spot-Comet-PanSTARRS-in-Twilight-196688441.html

PANSTARRS Update Monday, March 25, 2013

C/2011 L4 PANSTARRS remains a binocular object for northern hemisphere observers.  Recently it has been estimated to be at 1.8 magnitude but due to the twilight glare it remains undetectable to most naked-eye observers.  To find the comet you now need to scan the skies at an azimuth of about 283 degrees and about 12 degrees above the horizon at the end of civil twilight. 

http://www.skyandtelescope.com/observing/highlights/Spot-Comet-PanSTARRS...

PANSTARRS Update Monday, April 1, 2013

C/2011 L4 PANSTARRS has been climbing higher in the sky and now has an azimuth of roughly 290 degrees and an altitude of 25 degrees.  It has also begun to fade and is now a 3^rd magnitude object.  Start looking in the western skies about 30 minutes after sunset.

PANSTARRS Update Monday, April 8, 2013

C/2011 L4 PANSTARRS is still visible in the early evening skies about 30 minutes after sunset.  Looking to the northwest during dusk the comet is about 12 degrees above the horizon.  For those willing to get up before sunrise, the comet is now higher above the horizon at dawn than it is during dusk.  Around 6:00 a.m. look to the northeast about 20 degrees above the horizon.   Recent estimates for the comets brightness have it a 4^th magnitude. 

C/2012 S1 ISON

The second comet for this year comes much later in late November and December and is called C/2012 S1 ISON.  This comet is predicted to get as bright as the full moon if it survives its perihelion.  It is hard to not get our hopes up for predictions like this but comets are fickle things and do not always behave as predicted.  Also of interest is this comet might produce a meteor shower sometime in early 2014.  If this is the case it should be a spectacular shower that could even turn into a meteor storm.  Stay tuned for more information on this comet as we get closer to the end of the year.        

Constellation of the Month

Each month we will highlight one constellation and some of the objects that can be found within the boundaries of that constellation.  At the start of the month we will list only a few of these objects and each week we will add another to the list.  Some objects will be visible to the unaided eye and some may require a telescope.  Many of the objects listed will require a map of the sky to find or may require repeat observations to notice various properties.  Links to star charts and other information that will be useful in identifying the objects listed will be given at the end of each week’s section. 

This month our constellation is Cancer the Crab.  Cancer is one of the 12 zodiacal constellations meaning that Sun, Moon and planets can be found in Caner from time to time.  It is located in the spring seasonal sky between the constellations of Gemini and Leo.  Cancer is significantly fainter then its neighbors and may be difficult to spot in light polluted conditions.   To locate Cancer either find Gemini to the upper left of Orion or Leo just below the Big Dipper’s bowl.  Cancer is west of Leo and east of Gemini.  The brightest stars in Caner form a faint upside down Y-shape.  The brightest stars are Acubens, Altarf, Asellus Borealis, Asellus Australis, ζ Cnc, ι Cnc and 55 Cnc.

http://iau.org/static/public/constellations/pdf/CNC.pdf

In Greek mythology, Cancer was the giant crab that nipped at the feet of Hercules as he battled Hydra.  In ancient Egypt, Cancer was seen as the lowly scarab which was the representation of the dawn Sun-God Khephri.  It was also a symbol of fertility.

The object for the week of April 1 is Cancer’s brightest and most well known deep sky object known as M44.  Also known as the Beehive cluster or the Praesepe Cluster, M44 is an open cluster containing 350 stars shining with a combined magnitude of 3.7.  At this magnitude, M44 is visible to the unaided eye as a faint patch of nebulous light using averted vision.  Through binoculars you can easily count over 40 stars and with a large telescope roughly 200 can be seen.  The stars in this cluster are approximately 730 million years old and are 577 light years away.   

To find M44 look for the star Asellus Australlis at the branch of the upside down Y-shape described above.  From that star look approximately two degrees to the north and west and you will find M44.

http://iau.org/static/public/constellations/pdf/CNC.pdf

http://messier.seds.org/m/m044.html

The object for the week of April 8 is the open star cluster M67.  Discovered in the late 1700’s, this cluster stands as one of the oldest open clusters in the Milky Way.  Previous open clusters discussed in the Night Sky Update have been hundreds of million years old whereas M67 has been estimated to be 3.2 to 4 billion years old.  Open clusters normally do not last this long due to gravitational encounters that strip members from the cluster as it moves through the Milky Way.  M67 is also relatively close at a distance of 2,700 light years making it an ideal target to study the evolution of stars.  Being so close to us, our view of M67 is mostly unobstructed by the clouds of soot and dust that permeate the Milky Way.  So the light we see from these stars has gone through very little change or filtering as it travels to us.  In M67 there are nearly 200 white dwarfs, main sequence stars of all types and a number of aging giant stars.  With this spread scientists have clear views of nearly all types of stars in various evolutionary stages. 

To find M67 look for the upside down Y-shape of Cancer.  The bottom left star of the Y-shape is Acubens.  From there look about 1.5 degrees to the west and you will find M67.  With an apparent magnitude of 6.1, M67 is an easy target for binoculars.  City lights will make things much more difficult but it should be visible.  Through a telescope stars in M67 can be resolved with a faint patch of nebulous light in the background.    

http://iau.org/static/public/constellations/pdf/CNC.pdf

http://messier.seds.org/m/m067.html

NASA Mission of the Month

Each month we will be celebrating a NASA mission of the month.  This month’s mission is the Hubble Space Telescope.  This telescope is named after the famous astronomer Edwin Hubble who showed us that the universe was huge and was expanding at exceeding rates.  This discovery revolutionized astronomy.  Much like the astronomer, the telescope continues to push our understanding of the universe and allows astronomers to see some of the most distant objects ever observed.  The Hubble Space Telescope has been in space now for over 20 years and has made over 1 million observations.  It continues to shed light on the universe and its origin.  To learn more about the Hubble Space Telescope visit

http://hubblesite.org/

50^th Anniversary of the James S. McDonnell Planetarium

2013 marks the 50^th anniversary of the James S. McDonnell Planetarium.  There are a number of events planned for the year that will celebrate the 50^th anniversary.  For more information about the planetarium and the 50^th anniversary, visit www.slsc.org

Our next Star Party will be held on Friday, May 3, 2013, from dusk until 10 p.m.
Weather permitting, the St. Louis Astronomical Society and the Science Center will set up a number of telescopes outdoors and be on-hand to answer your questions.  Telescope viewing begins at 8:00 p.m.  Regardless of the weather on May 3, join us indoors in our Planetarium Theater for “The Sky Tonight”.  Showtime is at 8 p.m.

This free, indoor star program will introduce you to the current night sky, the planets, and the seasonal constellations. Doors open 15 minutes before show time. Shows begins at 8 p.m. Sorry, no late admissions due to safety issues in the darkened theater.

The St. Louis Astronomical Society hosts the monthly Star Parties at the Science Center which are held on the first Friday of each month. Our Monthly Star Parties are open to the public and free of charge.  For more information about the St. Louis Astronomical Society visit their website at www.slasonline.org