October 17, 2013

StarGeezer’s Sky-Lights (SM) for the week of October 13-20

Friday, October 15 Keen eyed observers keep your eyes peeled for a very subtle “penumbral” lunar eclipse Friday evening, October 18.

The penumbra is the outer ring of Earth’s shadow. Since Luna will be north of the ecliptic only 75% of its disc will immerse in Earth’s penumbral shadow. 

lunar-eclipse-3-nov-03-text.jpgImage left: I took this shot of a lunar eclipse several years ago. During that eclipse the Moon was south of the ecliptic. Notice the brightness at the Moon’s lower limb which is the edge of Earth’s shadow. This is opposite of the situation for Friday night’s eclipse. This time look for a delicate darkening in this same area of the Moon.

The Moon will be most deeply in the Earth’s outer shadow at 23:50 UT (7:50 PM EDT). As the Moon rises Friday evening it will be mid-eclipse for those in the eastern third of north and south America. Observers in Africa and Europe are ideally placed for this eclipse, however subtle it will be. Those in Asia will see just the first part of the eclipse as the Moon is setting Saturday morning.

Note that the Moon looks a little smaller because it will be just 6 days from apogee, furthest from Earth. Can you detect the very slight graying along the southeastern (bottom right) lunar limb?

In the southeastern U.S. be watching Friday evening as the Moon rises in the East just after sunset. For an excellent animation of the dynamics of this eclipse visit Larry Koehn’s excellent website  ShadowandSubstance.com.

For more detailed information visit the NASA Eclipse Website

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October 7, 2013

Radio Amateurs Say “Hi” to Juno Spacecraft Wednesday, October 9

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NASA’s Juno spacecraft will fly past Earth on October 9, 2013 to receive a gravity assist from our planet, putting it on course for Jupiter. To celebrate this event, the Juno mission is inviting amateur radio operators around the world to say “HI” to Juno in a coordinated Morse Code message. Juno’s radio & plasma wave experiment, called Waves, should be able to detect the message if enough people participate.

 Juno is going to Jupiter to study plasma/aurora/radio emissions at Jove. The Waves instrument aboard Juno was built at The University of Iowa Dept. of Physics and Astronomy in Van Allen Hall, for the study of radio and plasma waves at Jupiter. It is specifically targeted at the Jovian auroral region, and JPL hopes to fly directly through the auroral acceleration region where Jovian decametric signals are generated

During Wednesday’s fly by JPL is inviting radio amateur’s to partipate in a propagation experiment on 10 meters which will test the WAVES instrument. Click here for Say Hi to Juno

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September 28, 2013

StarGeezer’s Sky-Lights (SM) for the week of September 30-October 7

ISS will make visible passes over North America Tuesday and Thursday evenings

Tuesday October 8 The International Space Station will make a couple of very fine evening appearances over the midwest on Tuesday and Thursday evenings at approximately 8:20 pm EDT. Click Heavens-Above for sightings at your location

 Friday, October 4 New Moon and start of lunation 1123 at 8:33 pm (0:33 UT October 5). You won’t be able to see this but give a try at spotting the 46 hour old Moon Sunday evening and the quadruple conjunction (see below) Monday evening when Luna is 72 hours old on the “other side of dawn”

Saturday, October 5 The 22 hour old Moon will occult the first magnitude star Spica in constellation Virgo. This occultation will begin around 4pm Saturday afternoon. Unfortunately the 22 hour old crescent Moon will be invisible in the late afternoon sky east (left) of the Sun. There will be another occulation of Spica on November 29th and this one will be visible over much of north America. I am planning to observe this occulation. If you would care to join me me contact me here

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Monday, October 7 The Moon joins Venus, Saturn and Mercury for a beautiful grouping at dusk. Mercury will fall back past Saturn on October 30 and meet the ringed planet again November 26th in the pre-dawn sky. The sky map at left shows the view toward the southwestern horizon this evening around 7:20 pm local time

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September 26, 2013

Watch ISS and Cygnus flying in formation

If you enjoy observing orbiting spacecraft like ISS here’s a unique opportunity to watch an orbiting “convoy”. Orbital Sciences Corporation’s Antares-Cygnus cargo vehicle was launched on September 18. The original plan was for Cygnus to dock at ISS on Sunday morning, September 22nd

The rendezvous, capture and berthing of the Cygnus cargo vehicle was postponed early Sunday when a “data format discrepancy” between the ISS onboard navigation system and a similar system aboard Cygnus caused mission managers with Orbital and NASA to postpone the approach and capture of the vehicle

Its been a busy week at ISS. The Expedition 38 crew launched from Baikonour aboard Soyuz TMA-10 and docked at ISS Wednesday, September 25. With the crew rotation and docking pending NASA prudently decided to park Cygnus in an orbit trailing ISS and postpone the docking until after Expedition 38’s arrival at the orbiting outpost

As of Thursday afternoon, September 26, Orbital’s website says that Cygnus is following ISS at a distance of about 1490 miles but will be gradually closing on the station in anticipation of a possible rendezvous, capture and berthing Sunday morning, September 29

This affords alert observers an opportunity to watch for Cygnus following ISS during visible passes until the spacecraft are mated

I’ve checked Heavens-Above for upcoming visible passes at my location in southern Indiana. There aren’t any “good” ones until Monday morning but there will be low, visible, morning passes daily

They are: Friday 27 Sep 6:13-6:16 AM peaks 13 degrees NNW-NE and Saturday 28 Sep, 7:00-7:06 AM peaks 35 degrees NW-E (this will be the best pass prior to Sunday) Check visible passes for your location

I have seen ISS and Space Shuttles and ISS and a Russian Progress cargo vehicle flying in formation and it is a spectacular sight. If Cygnus is following station at 1500 miles I calculate it will trail ISS by about 5 minutes

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August 16, 2013

Update on Nova Dephini 2013

Update! As of Friday morning, August 16. Observers are reporting Nova Delphini 2013 at magnitude 4.4

The nova is still brightening at a steady pace. It may become brighter yet

Nova Dephini 2013  is bright enough to be seen with binoculars under bright urban skies and naked eye in rural areas under dark skies

Here is an excellent finder chart from Sky and Telescope.  Also, see the finder I prepared in the post below this one

This is a 10 degree wide magnitude comparison chart from AAVSO

Here is the discovery announcement from the IAU Bureau of Astronomical Telegrams

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August 15, 2013

Nova discovered near Delphinus

A magnitude 6.3 nova was discovered by Koichi Itagaki of Yamagata, Japan August 14. The nova is located between constellation Delphinus and Sagitta at RA 20h 23′ 31″, Dec +20 46′. At magnitude 6.3 this object may just be visible to keen eyed naked eye observers under pristine dark skies

Reports I have seen indicate this nova is an easy target with binoculars or small telescope. Itagaki reportedly first imaged the nova with a 7 inch reflector and later confirmed the sighting with a 23 inch reflector and CCD imaging. Delphinus is ideally positioned high in the evening sky just north of Altair, the western most star in the Summer Triangle

This area of the sky is high overhead near zenith at 10 pm local time

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Star hop from the “nose” of Delphinus to star 29 Vulpecula, then on to magnitude 5.7 HIP100754 (marked “57″ in the map diagram) and then southeast to the nova. Chart prepared with Starry Night Pro. Click map to enlarge

The nova is currently designated PNVJ20233073+2046041, let’s hope that it’s soon changed to Nova Delphini 2013!

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Reversed black on white chart which may make it easier for you to locate the nova. Created with Chris Marriott’s SkyMap

For more information visit American Association of Visible Star Observers

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August 10, 2013

StarGeezer’s Sky-Lights (SM) for the week of August 11-17

The StarGeezer’s “Sky-Lights” (SM) for the week of August 11-17, 2013

Here is my selected list of special astronomical highlights which will be visible to the backyard astronomer and historic milestones in astronomy and spaceflight this week

The Perseid meteor shower will be the premiere observing activity this week. Do your meteor observing in the pre-dawn hours Monday and Tuesday mornings. Observers in central South America will be treated to a beautiful occultation of a double star in the constellation Libra Tuesday evening

Monday and Tuesday, August 12-13

The Perseid meteor shower peaks Sunday and Monday nights. The peak activity is expected to happen around 19 hours universal time (3 pm EDT) Monday which is good news for observers in Asia

11400meteorshower.jpgObservers in the Americas should plan to watch the Perseids in the pre-dawn hours Monday and Tuesday mornings

Situate yourself in a hammock, lawn chair or on a blanket away from the glare of outdoor lighting. Position yourself to view the darkest part of the sky which is usually directly overhead. The Perseid’s “radiant”, the point at which they appear to originate from will rise in the northeast around 11 pm local time. Focus your view about 45 degrees off the radiant point, which will generally be to the southeast or southwest. This will be an excellent year for observing the Perseids. The Moon will not be a factor as it will set around 11 pm local time. Glare from light pollution will be the major factor in the number of meteors visible.

Meteor observer Paul Jones, observing in north Florida reported hourly rates of 18 and 23 on August 8/9. Observer Paul Martsching in Ames, Ia observed 6, 6 and 9 meteors per hour August 7/8

Robert Lunsford of the International Meteor Organization offers this forecast for the 2013 Perseids:

The Perseids (PER) reach maximum activity on August 12 from a radiant located at 03:12 (048) +58. This position lies where the borders of Perseus, Cassiopeia, and Camelopardlis meet. The nearest star of note would be third magnitude Gamma Persei, which lies four degrees south of the radiant. The radiant is best placed during the last hour before the start of morning twilight when it lies highest in a dark sky. Predawn rates this weekend would be near forty as seen from mid-northern latitudes and ten as seen from south tropical latitudes. Activity from this source is not visible south of 40 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift

Here is an excellent guide to Advanced Meteor Observing from Sky and Telescope magazine and a rather crazy take on meteor showers from XKCD.com

Tuesday, August 13

The Moon is at First Quarter. This evening the Moon occults the double star Alpha Librae, Zubenelgenubi, for observers in central South America at approximately 0 hours universal time (8 pm EDT)

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If you’re somewhere other than central South America use the Moon to locate the fine double star which will be above right of the Moon. Can you separate the two stars naked eye? Binoculars or a small telescope will resolve the pair. Chart shows view to the southwest Tuesday evening at 9 pm local time. Click to enlarge

Read details here from the International Occultation Timing Association

Wednesday, August 14

The faint glow of the Milky Way arches high across the evening sky at this time of year

Look to the southeast below and left of the Moon this evening and try to spot the “teapot” shape of constellation Sagittarius

Your view will be toward the center of our galaxy and the faint glow of the Milky Way will rise from the “spout” of the teapot up through Cygnus, the “northern cross” and on toward the “W” shape of Cassopeia high to the northeast

Thursday, August 15

The magnitude zero star Vega is directly overhead, zenith, at 9pm this week

Vega is the western-most member of the “Summer Triangle” of stars followed by Deneb and Altair

In the movie “Contact” Vega was the star Jodie Foster “teleported” to. Compare the brightness or magnitude of the trio.

Altair is the nearest of the three at 16.7 light years away and  brightest at magnitude 0.7. Vega is the second brightest of the trio at magnitude 0.3 and 25 light years distant.  Deneb shines a magnitude 1.3 but is much further away at an estimated distance of 1500 to 2500 light years. Compare the magnitude of the trio and consider that Deneb is estimated to be 60,000 time brighter than our Sun and remember that the photons of light which strike your eye tonight left the star around the year 500 B.C.

Friday, August 16

Look for the “Cat’s Eyes” the close naked eye double star at the tail of Scorpius tonight around 9:30 pm. See below

Coming attractions:

The Chinese Tiangong-1 space station will make a visible pass over the midwest Monday morning, August 19 at 09:53 UT (5:53 am EDT) peaking 72 degrees off the southeastern horizon. The station’s track will rise from the southwest and track to the north-northeast

The International Space Station will make a nearly overhead pass Friday evening, August 23 rising from the northwest at 01:42 UT (9:42 pm EDT) and cruising to the southeast. ISS’ track on this pass will peak at 87 degrees, nearly directly overhead

The visible spacecraft pass timings mentioned above are based on an observing location at Louisville, KY. For locations anywhere in the world click Heavens-Above
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Of special note: Scorpius, the scorpion, is one of the zodiacal constellations that is most easily recognized and spectacular. Visible along the southern horizon late evenings in July and mid evening in August the Scorpion is one of the most spectacular constellations. Locate red giant Antares to start your tour of the constellation of the Scorpion

Then find the “head” of the Scorpion a north-south trio of stars, Beta, Delta and Pi Scorpii a curved line of stars above and right of Antares. Scorpius’ body stretches down to the left toward the horizon and the stinger arcs back up to the left to star Lambda Scorpii, Shaula. Upsilan (Lesath) and Lambda Scorpii together are known as the “Cat’s Eyes” and are spectacular in binoculars or a telescope. Messier object M4 is a large globular cluster near the heart of the Scorpion. Scorpius is a truly spectacular constellation of the Summer sky and now is the time to enjoy its majesty

The sky map above left, prepared using Stellarium, demonstrates the view to the south horizon this week at 10:45 pm local time. Click any map image to enlarge

Share your observing notes or contact me with questions here

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June 24, 2013

How to spot Tiangong-1 The Chinese space station

The International Space Station will be “invisible” here in the midwest for the next couple of weeks. The station will make some pre-dawn appearances the week of July 15 with an excellent pass the morning of July 17th

There is, however, another “space station” for you to observe, the Chinese “Tiangong-1″ which is much smaller than ISS, actually about the size of Skylab or the Russian Mir. As I write this Monday evening, June 24, a crew of 3 is aboard Tiangong, two men and a woman. This is the fifth Chinese crew to reach orbit. This mission to Tiangong launched June 11 and is expected to de-orbit on Wednesday, June 26

Tiangong 1 will make visible morning passes during the coming week, the best of which will be Saturday morning, June 29 at 5:38 EDT (9:38 UT)

Other favorable passes here in the midwest will happen the mornings of July 1 and 2 as follows:

29 Jun 0.9 05:38:47 11° SW 05:41:21 61° SSE 05:44:07 10° ENE Visible

01 Jul 0.8 04:41:41 54° S 04:41:54 56° SSE 04:44:39 10° ENE Visible

02 Jul 1.0 04:58:25 27° W 04:59:42 63° NNW 05:02:28 10° ENE Visible

Data above indicates date, visible magnitude, time, bearing and elevation for the object
Tiangong-1 is much smaller and less bright than ISS. I have observed it once and it appears to be about the size and magnitude of a Russian Soyuz or Progress. For specific timings of orbital passes at your location click the Heavens Above link to the right

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June 21, 2013

When The Moon Hits Your Eye Like a Big Pizza Pie

full-harvest-moon.jpgSorry, it’s not “Amore”, but it will be the biggest, closest full Moon of 2013 

We’ll celebrate the Summer solstice with shortest nights and “biggest” Moon of the year this weekend

Take a gander at Luna on Saturday night or, better yet, just before dawn Sunday morning. This weekend’s full “Rose” Moon is superlative for several reasons. It will be the “largest” full Moon of the year because this lunar cycle’s perigee (closest to Earth) will be the nearest of the year. The moment of perigee happens at 11 hours UT (7 am EDT Sunday morning) just 33 minutes before the moment of full Moon at 11:33 UT (7:33 EDT) the closest coincidence of perigee and full Moon for the year

This full Moon will also be the lowest, furthest south, of the year. Can you figure out why the Moon is so low in the sky this month?

Quickstudy Quiz: Answer the question below and win a Quickstudy Laminated Stargazing guide from Barcharts.com

Q. Sidewalk Astronomer John Dobson once asked me “Why is the Moon nine times brighter at “full” phase than at first or last quarter?

The first email message to correctly answer John’s question about the brightness of the full Moon will win the laminated fold out 6 page Stargazing Quickstudy guide

 ”Know it Now, Use it Always with QuickStudy Laminated Reference Guide!”

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June 14, 2013

Watch the “Sunset Duo”, Mercury and Venus

Thursday evening, June 13th, the skies over southern Indiana were clear and crisp so I decided to get out and take a look at the “Sunset trio” of planets

Actually, the trio is now a duo as Jupiter will be at conjunction, on the far side of the Sun, June 19th, leaving Venus and Mercury to entertain skygazers at sunset

I ventured out on my deck around 9:15 pm and spotted sparkling Venus easily in the waning twilight

I have a “high” western horizon on my property, a tall tree line, so viewing things low in the west is nearly impossible

As the evening was crisp and cloudless I decided to jump in my truck and head to the nearby spot where I observe low western apparitions like this

The twilight had dimmed just enough at 9:45 pm, local time, 35 minutes after sunset for me to be able to spot the very dim Mercury

I found Mercury with binoculars about 4 degrees above left of sparkling Venus

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Chart to the left, prepared using Your Sky, shows Mercury and Venus positions on Sunday, June 16. Click to enlarge

Again, you will need a low, clear horizon to the west/northwest. Venus was only 6 degrees above my horizon at 9:45 pm

Mercury reached eastern elongation Wednesday, June 12. The most interesting exercise over the next few evenings will be watching as Mercury falls back toward the horizon. Tuesday through Thursday, June 18-20, Mercury will appear to drift past Venus. On Wednesday and Thursday the two planets will appear less than two degrees apart

Enjoy the view from night to night

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