[astronews] IAAS Monthly Astronomy Newsletter

  • From: Burness Ansell <ki0ar@xxxxxxxxx>
  • To: Astronomy Newsletter <astronews@xxxxxxxxxxxxx>
  • Date: Thu, 31 Jul 2008 20:20:08 -0700 (PDT)

             IAAS Monthly Astronomy Newsletter
                        August 2008


The International Association for Astronomical Studies provides this newsletter 
as a service for interested persons in the Denver Metro area. The astronomical 
data presented here is not only useful in Colorado but in other parts of the 
world as well.


                   ***** ATTENTION *****
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continue to receive the newsletter as usual but the link 
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link to http://www.ki0ar.com/astro.html. Thank you for your continued support.


This newsletter is published on the World Wide Web at 
http://www.ki0ar.com/astro.html  - The Home of KI0AR - and is received 
nationally and internationally. A MS Word formatted downloadable version of the 
newsletter is at http://www.ki0ar.com/current_nl.doc .


An Open Invitation - For amateur radio and scanner enthusiasts, when in the 
Denver metro area, please join the Colorado Astronomy Net on the Rocky Mountain 
Radio League (http://rmrl.hamradios.com/ ) repeater on a frequency of 146.94 
MHz on Tuesday nights at 7 P.M. local time.


Special Notice to Denver, CO area residents and visitors to the area: The 
Plains Conservation Center in Aurora hosts Full Moon Walks every month weather 
permitting on or near the night of the full Moon. Visit 
http://www.plainsconservationcenter.org  for more information and directions.


Excerpts from JPL mission updates are provided as a public service as part of 
the JPL Solar System Ambassador / NASA Outreach program.


In This Newsletter...

* The Moon
* The Planets
* Astronomical Events
* Planetary/Lunar Exploration Missions
* Web Sites of Interest
* Acknowledgments and References
* Subscription Information


New Feature - The Month At-A-Glance at http://www.ki0ar.com/ataglance.html 
I've added a link to a calendar displaying the daily astronomical events. 
Comments appreciated.


The Moon

* New Moon on the 1st.
* 1st Quarter Moon on the 8th.
* Full Moon on the 16th.
* Last Quarter Moon on the 23rd.

* Apogee on the 10th, 251,380 mi. from Earth.
* Perigee on the 25th, 229,097 mi. from Earth.

Moon/Planet Pairs:
* The Moon passes 2 deg. south of Venus on the 2nd.
* The Moon passes 4 deg. south of Saturn on the 3rd.
* The Moon passes 4 deg. south of Mars on the 4th.
* Venus passes 1.1 deg. north of Regulus on the 5th.
* Mercury passes 1.1 deg. north of Regulus on the 10th.
* The Moon passes 0.4 deg. south of Antares on the 10th.
* The Moon passes 3 deg. south of Jupiter on the 13th.
* Mercury passes 0.7 deg. south of Saturn on the 15th.
* The Moon passes 0.8 deg. north of Neptune on the 16th.
* The Moon passes 4 deg. north of Uranus on the 18th.
* Mercury passes 1.2 deg. south of Venus on the 23rd.


The Planets & Dwarf Planets
Planetary Reports generated by "TheSky" software. 
(http://www.ki0ar.com/planrpts.html ) These reports provide predicted data for 
the planets for the first of each month for the current year. The rise and set 
times for the Sun and the Moon for each day of the month are also included in 
the reports.
(All times are local unless otherwise noted.)

* Planetary Highlights for August - Several planets, some comets, plenty of 
meteors and a couple of eclipses are in store for viewers of the heavens this 

* Mercury - Has returned to the evening sky this month. Mercury sets at 8:30 
p.m. on the 1st and about 8:23 p.m. by month's end. Look for Mercury low in the 
west soon after sunset after mid-month. Mercury is in the constellation of Leo 
shining at magnitude -0.5

* Venus - Can be found low in the west soon after sunset. Venus will be the 
brightest object in the sky shining at magnitude -3.8. Keep an eye on Venus 
during the first 2 weeks of August as Venus and Saturn close in on each other. 
Venus sets at 8:59 p.m. on the 1st and about 08:28 p.m. by month's end. Venus 
is in the constellation of Leo.

* Earth - N/A.

* Mars - Is still visible in the evening sky after sunset. Mars sets at 9:56 
p.m. on the 1st and about 8:39 p.m. by month's end. Look for Mars a little bit 
higher than Saturn and Mercury. Mars is in the constellation of Virgo shining 
at magnitude 1.7.

* Jupiter - Is also visible in the evening sky for most of the night. Jupiter 
can be found in the southern sky after sunset. Jupiter sets at 4:03 a.m. on the 
1st and about 1:51 a.m. by month's end. Jupiter is in the constellation of 
Sagittarius shining at magnitude -2.6.

* Saturn - Is still visible in the early evening sky but just barely, not quite 
lost in the twilight glow during the first 2 weeks of August. Saturn sets 
around 9:33 p.m. on the 1st and about 7:40 p.m. by month's end. Saturn shines 
at magnitude 0.8 in the constellation of Leo.

* Uranus - Rises at 9:57 p.m. on the 1st and about 7:53 p.m. by month's end. 
Uranus is in the constellation of Aquarius shining at magnitude 5.7.

* Neptune - Is at opposition on the 15th. Neptune rises at 8:43 p.m. on the 1st 
and about 6:39 p.m. by month's end. Neptune is in the constellation of 
Capricornus shining at magnitude 7.8.

Dwarf Planets

* Ceres – Returns to the morning sky later in the month. Ceres rises at 3:22 
a.m. on the 1st and about 2:25 a.m. by month’s end. Ceres is in the 
constellation of Gemini shining at magnitude 8.8.

* Pluto - Sets at 3:16 a.m. on the 1st and about 1:13 a.m. by month's end. 
Pluto shines at magnitude 13.9 in the constellation of Sagittarius. As always, 
good luck at spotting this one, a large telescope and very dark skies will be 


Astronomical Events

Meteor Showers
* The Northern Delta Aquarids extends from July 16 to September 10. Maximum 
occurs on August 13. The hourly rates reach a high of 10.

* The Perseids meteor shower is generally visible between July 23 and August 
22. Maximum occurs during August 12/13. The hourly rate typically reaches 80, 
although some years have been as low as 4 and as high as 200. The meteors tend 
to be very fast, possess an average magnitude of 2.3 and leave persistent 

The 2008 Perseid Meteor Shower - 

* For more information about Meteor Showers, visit Gary Kronk's Meteor Showers 
Online web page at http://meteorshowersonline.com/ .

* Comet 6P/d'Arrest travels from the constellation of Aquila into the southern 
constellation of Microscopium. At 10th magnitude, you will need to view this 
comet under dark sky conditions. The best time this month is before August 6 or 
after August 23.

* Comet C/2007 W1 (Boattini) is slightly brighter than Comet d'Arrest but 
you'll have to wait until the pre-dawn hours to spot this comet traveling 
through the constellation of Aries the Ram.

* For information, orbital elements and ephemerides on observable comets visit 
the Observable Comets page from the Harvard-Smithsonian Center for Astrophysics 
(http://cfa-www.harvard.edu/iau/Ephemerides/Comets/index.html ).

* For more information about Comets, visit Gary Kronk's Cometography.com web 
page at http://cometography.com/ .

* A Solar eclipse occurs on the 1st over Asia with totality lasting about 2.5 
minutes. This eclipse begins in Northern Canada, crosses Greenland, Russia, 
Mongolia and China.
* A partial lunar eclipse occurs on the 16th, over Europe, Asia and Africa.

* Information on various occultations can be found at 
http://lunar-occultations.com/iota/iotandx.htm , the International Occultation 
Timing Association's (IOTA) web site.

Asteroids (From west to east)
* Parthenope is at opposition on the 6th in the constellation of Capricornus.
* Vesta is in the constellation of Cetus.
* Pallas is in the constellation of Eridanus.

* Information about the Minor Planets can be found at 
http://www.minorplanetobserver.com  the Minor Planet Observer web site.


Planetary/Lunar Exploration Missions
(Excerpts from recent mission updates)

* Cassini - July 30, 2008
NASA Confirms Liquid Lake on Saturn Moon

"PASADENA, Calif. -- NASA scientists have concluded that at least one of the 
large lakes observed on Saturn's moon Titan contains liquid hydrocarbons, and 
have positively identified the presence of ethane. This makes Titan the only 
body in our solar system beyond Earth known to have liquid on its surface. 

Scientists made the discovery using data from an instrument aboard the Cassini 
spacecraft. The instrument identified chemically different materials based on 
the way they absorb and reflect infrared light. Before Cassini, scientists 
thought Titan would have global oceans of methane, ethane and other light 
hydrocarbons. More than 40 close flybys of Titan by Cassini show no such global 
oceans exist, but hundreds of dark, lake-like features are present. Until now, 
it was not known whether these features were liquid or simply dark, solid 

"This is the first observation that really pins down that Titan has a surface 
lake filled with liquid," said Bob Brown of the University of Arizona, Tucson. 
Brown is the team leader of Cassini's visual and mapping instrument. The 
results will be published in the July 31 issue of the journal Nature."

Cassini Imaging Team's website - http://ciclops.org .

For the latest mission status reports, visit 
http://saturn.jpl.nasa.gov/home/index.cfm .  The speed and location of the 
spacecraft can be viewed on the "Present Position" web page.
(http://saturn.jpl.nasa.gov/operations/present-position.cfm )

* New Horizons - July 29, 2008
The PI's Perspective: Journeying Beyond Saturn

"As avid followers of New Horizons know, our spacecraft has been mostly 
hibernating since February, and will continue to so do until Sept. 2, when we 
will wake it to begin its second annual checkout. Many of you will also recall 
that New Horizons passed the orbit of Saturn in early June. New Horizons is the 
first spacecraft to venture this far (a billion kilometers from the Sun!) since 
the last of the Voyagers accomplished the same milestone in the summer of 1981. 
We are now nearly 96 million kilometers (60 million miles) beyond Saturn, and 
will cross the orbit of Uranus – about 2 billion kilometers from the Sun – in 
March 2011."

New Horizons gallery http://pluto.jhuapl.edu/gallery/sciencePhotos/ .

For more information on the New Horizons mission - the first mission to the 
ninth planet - visit the New Horizons home page: http://pluto.jhuapl.edu/ .

* Dawn - No new news since December 18, 2007
NASA's Dawn Spacecraft Begins Interplanetary Cruise Phase

"NASA's Dawn spacecraft has successfully completed the initial checkout phase 
of the mission and begun its interplanetary cruise phase, which is highlighted 
by nearly continuous thrusting of its ion propulsion system. Dawn is on an 
8-year, 3-billion mile journey to asteroid Vesta and dwarf planet Ceres."

For more information on the Dawn mission, visit the Dawn home page: 
http://www.nasa.gov/mission_pages/dawn/main/index.html .

* MESSENGER - July 3, 2008
MESSENGER Settles Old Debates and Makes New Discoveries at Mercury

"Scientists have argued about the origins of Mercury’s smooth plains and the 
source of its magnetic field for over 30 years. Now, analyses of data from the 
January 2008 flyby of the planet by the MESSENGER spacecraft have shown that 
volcanoes were involved in plains formation and suggest that its magnetic field 
is actively produced in the planet’s core and is not a frozen relic. Scientists 
additionally took their first look at the chemical composition the planet’s 
surface material. The tiny craft probed the composition of Mercury’s thin 
atmosphere, sampled charged particles (ions) near the planet, and demonstrated 
new links between both sets of observations and materials on Mercury’s surface. 
The results are reported in a series of 11 papers published in a special 
section of the July 4 issue of Science magazine."

For more information on the MESSENGER mission, visit the MESSENGER home page: 
http://messenger.jhuapl.edu/ .

* Pack Your Backpack
Calling all explorers! Tour JPL with our new Virtual Field Trip site. Stops 
include Mission Control and the Rover Lab. Your guided tour starts when you 
select a "face" that will be yours throughout the visit. Cool space images and 
souvenirs are all included in your visit.
+ http://virtualfieldtrip.jpl.nasa.gov/ 
* Past, Present, Future and Proposed JPL Missions - 
http://www.jpl.nasa.gov/missions .

* For special JPL programs and presentations in your area visit the JPL Solar 
System Ambassador web site at http://www2.jpl.nasa.gov/ambassador/index.html .

Mars Missions

* Mars Odyssey Orbiter - No new news since March 20, 2008
NASA Mission Finds New Clues to Guide Search for Life on Mars

"PASADENA, Calif. - NASA's Mars Odyssey orbiter has found evidence of salt 
deposits. These deposits point to places where water once was abundant and 
where evidence might exist of possible Martian life from the Red Planet's past.

A team led by Mikki Osterloo of the University of Hawaii, Honolulu, found 
approximately 200 places on southern Mars that show spectral characteristics 
consistent with chloride minerals. Chloride is part of many types of salt, such 
as sodium chloride or table salt. The sites range from about a square kilometer 
(0.4 square mile) to 25 times that size."

"A simulated fly-through using the newly assembled imagery is available online 
at http://www.nasa.gov/mission_pages/mars/missions/odyssey/20060313.html .

The fly-through plus tools for wandering across and zooming into the large 
image are at http://themis.asu.edu/ ."

Thermal Emission Imaging System (THEMIS) web site: (http://themis.asu.edu/ )

July 21-25, 2008

* THEMIS ART #94 (Released 21 July 2008)

* THEMIS ART #95 (Released 22 July 2008)

* THEMIS ART #96 (Released 23 July 2008)

* THEMIS ART #97 (Released 24 July 2008)

* THEMIS ART #98 (Released 25 July 2008)

All of the THEMIS images are archived here:

The Odyssey data are available through a new online access system established 
by the Planetary Data System at: http://starbrite.jpl.nasa.gov/pds/ 

Visit the Mars Odyssey Mission page at 
http://mars.jpl.nasa.gov/odyssey/index.html .

* Mars Exploration Rover Mission (Spirit and Opportunity) -
July 4, 2008

Spirit Status: Biding Time - sol 1594-1600, June 27-July 03, 2008

"Spirit continues to ride out the Martian winter by doing minimal activities to 
conserve power. The rover conducts very light science activities every three to 
four Martian days, or sols, and relays data to NASA's Odyssey orbiter for 
transmission to Earth every 4 sols. The rest of the time, Spirit mostly sleeps.

As it has been some time since Spirit's operators were able to synchronize the 
spacecraft clock to Earth time, they wished to determine how far the spacecraft 
clock had drifted (how much it had changed over time). Synchronization of the 
clock is a process that requires a power-intensive, two-way, X-band 
communications link. When the power situation allowed it, they decided to 
perform an X-band "beep" (a five-minute, low-gain communication session) to 
estimate the amount of drift. The transmission of plans to do so on sol 1594 
(June 27, 2008) were not detected by the ground station. Engineers hoped to 
make another attempt on sol 1604 (July 7, 2008).

Spirit is healthy and all subsystems were performing as expected as of the 
Odyssey downlink on sol 1598 (July 1, 2008). Solar-array energy has been steady 
within the range of 225 watt-hours to 230 watt-hours (100 watt-hours is the 
amount of energy needed to light a 100-watt bulb for one hour)."

Opportunity Status: Rover Takes Photos of Scenic View - sol 1574-1580, June 
28-July 04, 2008

"Opportunity has completed work on the stand-off portion of the full-color 
panorama of the layered cliff known as "Cape Verde." It may take a couple of 
weeks for the entire panorama to arrive on Earth, depending on the volume of 
data the rover is able to transmit during communications links.

Next, Opportunity will move closer to Cape Verde to take a high-resolution 
image of a smaller area in front of the rover.

During the past week, engineers characterized the performance of the rover's 
rock abrasion tool along the z-axis by comparing voltage and the speed of the 
actuator at different temperatures. In the event that the z-axis encoder lines 
break, as have the encoder lines for the rotate and revolve axes, this 
characterization will be essential in developing a functional strategy for 
operating the rock abrasion tool with full, open-loop control. The z-axis 
encoder is responsible for moving the cutting head outward into the rock.

Next week's plans call for Opportunity to bump forward to a point only a few 
meters away from the cliff face to take high-resolution images. If possible, 
Opportunity will also conduct scientific studies of an outcrop target called 
"Nevada" (so named because of a rock next to it which has a shape reminiscent 
of the outline of the state of Nevada) using instruments on the robotic arm.

Opportunity is healthy and all subsystems are performing as expected. Energy is 
around 376 watt-hours (100 watt-hours is the amount of energy required to light 
a 100-watt bulb for one hour). As of Sol 1578 (July 2, 2008), Tau (a measure of 
darkness due to atmospheric dust) was at 0.413 and the dust factor (a measure 
of the proportion of sunlight penetrating dust on the solar arrays) was at 

Landing sites link - http://marsoweb.nas.nasa.gov/landingsites/ 
Visit the Mars Exploration Rover page at
 http://marsrovers.jpl.nasa.gov/home/index.html .

* Mars Reconnaissance Orbiter Mission - July 16, 2008
NASA Spacecraft Shows Diverse, Wet Environments on Ancient Mars

"WASHINGTON -- Two studies based on data from NASA's Mars Reconnaissance 
Orbiter have revealed that the Red Planet once hosted vast lakes, flowing 
rivers and a variety of other wet environments that had the potential to 
support life. 

One study, published in the July 17 issue of Nature, shows that vast regions of 
the ancient highlands of Mars, which cover about half the planet, contain clay 
minerals, which can form only in the presence of water. Volcanic lavas buried 
the clay-rich regions during subsequent, drier periods of the planet's history, 
but impact craters later exposed them at thousands of locations across Mars. 
The data for the study derives from images taken by the Compact Reconnaissance 
Imaging Spectrometer for Mars, or CRISM, and other instruments on the orbiter. 

"The big surprise from these new results is how pervasive and long-lasting 
Mars' water was, and how diverse the wet environments were," said Scott 
Murchie, CRISM principal investigator at the Johns Hopkins University Applied 
Physics Laboratory in Laurel, Md."

July 30, 2008

* Layers Exposed Near the Mouth of Ladon Valles

* Stair-Stepped Mounds in Meridiani Planum 

* Dunes and Polygons 

* The Head of Athabasca Valles

All of the HiRISE images are archived here:

More information about the MRO mission is available online at 
http://www.nasa.gov/mro .

* Phoenix Mars Lander Mission - July 31, 2008
NASA Spacecraft Confirms Martian Water, Mission Extended

"TUCSON, Ariz. -- Laboratory tests aboard NASA's Phoenix Mars Lander have 
identified water in a soil sample. The lander's robotic arm delivered the 
sample Wednesday to an instrument that identifies vapors produced by the 
heating of samples. 

"We have water," said William Boynton of the University of Arizona, lead 
scientist for the Thermal and Evolved-Gas Analyzer, or TEGA. "We've seen 
evidence for this water ice before in observations by the Mars Odyssey orbiter 
and in disappearing chunks observed by Phoenix last month, but this is the 
first time Martian water has been touched and tasted." 

With enticing results so far and the spacecraft in good shape, NASA also 
announced operational funding for the mission will extend through Sept. 30. The 
original prime mission of three months ends in late August. The mission 
extension adds five weeks to the 90 days of the prime mission. 

"Phoenix is healthy and the projections for solar power look good, so we want 
to take full advantage of having this resource in one of the most interesting 
locations on Mars," said Michael Meyer, chief scientist for the Mars 
Exploration Program at NASA Headquarters in Washington."

Visit the Phoenix Mars Lander Mission pages at 
http://www.nasa.gov/mission_pages/phoenix/main/index.html .

* Mars Missions Status - New Mars missions are being planned to include several 
new rover and sample collection missions. Check out the Mars Missions web page: 
http://mars.jpl.nasa.gov/missions/  and the Mars Exploration page: 


Links and Other Space News
(If you have a link you would like to recommend to our readers, please feel 
free to submit it.)


* "TheSky" Software - http://www.bisque.com 

* A Short Guide to Celestial Navigation - http://www.celnav.de/ 

* Astrogirl Homepage - http://www.astrogirl.org 

* Astronomical Lexicon - http://www.ki0ar.com/astrolex.html 
Many of the astronomical terms used in this newsletter are defined here.

* Astronomy Picture of the Day - http://antwrp.gsfc.nasa.gov/apod/astropix.html 

* Celestron Telescopes - http://www.celestron.com/c2/index.php - New beta 

* Cloudbait Observatory, Guffey Colorado - http://www.cloudbait.com   - Submit 
your fireball reports here. Interesting, knowledgeable site.

* The Constellations and Their Stars - 
Good site for finding out more about the 88 constellations and their associated 

* Denver Astronomical Society - http://www.denverastrosociety.org 

* Distant Suns - http://www.distantsuns.com/ 
Desktop Astronomy package for PCs.

* Eric's Black Sun Eclipse website -

* Groovy Adventures - http://www.groovyadventures.com 
Unique adventures and vacations including astronomy related vacations.

* JPL Solar System Ambassador Program -

* JPL Solar System - http://www.jpl.nasa.gov/solar_system/ 

* Meade Advanced Products Users Group - http://www.mapug-astronomy.net/  - 
Mapug-Astronomy Topical Archive & information resource, containing a massive 
335 page archive of discussions about Meade equipment, and much more: 
observatories, observing lists, permanent piers, equatorial wedges, remote 
operations, software, eyepieces, etc.

* My Stars Live - http://www.mystarslive.com/ 
Interactive Star Chart

* NASA Science News - http://science.nasa.gov/ 

* Northern Colorado Astronomical Society - http://ncastro.org/ 

* Sangre Stargazers - http://sangrestargazers.skymtn.com/  - New astronomy club 
in the Wet Mountain Valley of Custer County (about 45 miles due west of Pueblo, 

* Sky and Space - http://www.skyandspace.com.au/public/home.ehtml 
Astronomy from Down Under - The Southern Hemisphere's first astronomy and space 

* Skywatch Sightings from NASA - 
This site gives you the best times to watch the ISS pass over or near your 

* Southern Colorado Astronomical Society - http://www.scasastronomy.info/

* Space.com - http://space.com 
Interesting space and astronomy articles.

* Space.com - Sky Watch Calendar -

* Spaceflight Now - http://spaceflightnow.com/ 

* "SpaceRef.com" - http://www.spaceref.com/  - SpaceRef's 21 news and reference 
web sites are designed to allow both the novice and specialist alike to explore 
outer space and Earth observation.
This site includes links to planetary updates such as Mercury Today, Venus 
Today, Earth Today, Moon Today, Mars Today, Jupiter Today, Saturn Today, Pluto 
Today, etc.

* Universe Today - http://www.universetoday.com 


Acknowledgments and References

Much of the information in this newsletter is from "Astronomy Magazine" 
(Kalmbach Publishing), JPL mission status reports, the Internet, "Meteor 
Showers - A Descriptive Catalog" by Gary W. Kronk, Sky & Telescope web pages 
(S&T), and other astronomical sources that I have stashed on my book shelves.

The author will accept any suggestions, constructive criticisms, and 
corrections. Please feel free to send me any new links or articles to share as 
well. I will try to accommodate any reasonable requests. Please feel free to 
send questions, comments, criticisms, or donations to the email address listed 
below. Enjoy!


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Keep looking UP!
73 from KI0AR

Created by Burness F. Ansell, III

COO, Director of Aerospace Technologies, IAAS
JPL Solar System Ambassador, Colorado
Last modified: July 31, 2008

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