Astronomy News for the Month of August 2017

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For amateur radio operators and scanner enthusiasts, when in the Denver metro area, please join the Colorado Astronomy Net on the Rocky Mountain Radio League's 146.94 MHz and 449.825 MHz repeaters. The RMRL 146.94 repeater is also linked with the WB0WDF Cripple Creek 447.400 MHz repeater and Allstar nodes 28298, 28299 and 29436. We are also linked via Echolink, links are k0jsc-r and canoncty. More information on the WB0WDF repeater links and Allstar nodes and Echolinks can be found at The net meets on Tuesday nights at 7 P.M. Mountain Time (US).

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In this Newsletter...

Background screen credits: NGC5775
Imaged March 21/22, 2001
using the 16" Kitt Peak Visitors Center telescope
as part of the Kitt Peak Advanced Observing Program.

Total Solar Eclipse 2017
August 21, 2017
Links and Information

The Month At-A-Glance
A calendar displaying the daily astronomical events.

14 day moon

The Moon



Moon/Planet Pairs

For reference: The Full Moon subtends an angle of ~0.5°.

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The Planets & Dwarf Planets

Planetary Reports generated by "TheSky" software. 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 as well as meteor shower radiants are also included in the reports. These reports have been optimized for the Denver, Colorado location, however, the times will be approximate for other locations on Earth.

(All times are local unless otherwise noted.)

Planetary Highlights for August

Planets and Meteors and Eclipses! Oh My!

August 2017 is an exceptional month for viewing of all kinds. Start the month off by trying to spot Mercury after sunset during the first week of August. Then view Jupiter and Saturn in the early evenings, followed by Neptune and Uranus in late evening and after midnight. Venus shines brightly as the "morning" star.

One of the best meteor showers occurs this month as well. The Perseids spans a period of August 5th through the 19th, peaking on the morning of the 12th before sunrise. However, a waning gibbous Moon may interfere with many of the dimmer meteors.

The main event though occurs on the 21st. The "Eclipse Across America" occurs on this date when the shadow of the Moon eclipsing the Sun travels from Oregon to South Carolina.


Is stationary on the 12th. Mercury is in inferior conjunction with the Sun on the 26th. Mercury sets at 9:15 p.m. on the 1st and about 6:50 p.m. by month's end. Look for Mercury in the west about 30 minutes after sunset. Mercury will be best viewed during the first week of the month above the western horizon. After inferior conjunction, Mercury returns to the morning sky but will be lost in the morning twilight glow. Mercury is in the constellation of Leo this month shining at magnitude 0.4 on the 1st.


Rises at 3:02 a.m. on the 1st and about 3:49 a.m. by month's end. Look for Venus shining brightly in the early morning hours before sunrise. Venus moves from the constellation of Gemini into Cancer shining at magnitude -4.0.




Even though Mars has returned to the morning sky after reaching conjunction with the Sun last month, Mars still remains lost in the Sun's twilight glow and will return to view sometime in September. Mars moves from the constellation of Cancer into Leo.


Sets at 11:05 p.m. on the 1st and about 9:15 p.m. by month's end. By the time the Sun sets, Jupiter is high in the evening sky towards the west and will be the first object visible as the skies darken besides the Moon. Jupiter is in the constellation of Virgo shining at magnitude -1.8.


Sets at 2:29 a.m. on the 1st and about 12:25 a.m. by month's end. Saturn is easily spotted soon after sunset towards the south. Saturn is in the constellation of Ophiuchus shining at magnitude 0.3.


Is stationary on the 3rd. Uranus rises at 11:25 p.m. on the 1st and about 9:22 p.m. by month's end. Uranus is best viewed in the late evening and early morning skies before sunrise. Uranus is in the constellation of Pisces shining at magnitude 5.8.


Rises at 9:39 p.m. on the 1st and about 7:35 p.m. by month's end. Neptune is best viewed in the evening and early morning hours. Neptune is in the constellation of Aquarius shining at magnitude 7.8.

Dwarf Planets


Rises at 4:29 a.m. on the 1st and about 3:23 a.m. by month's end. Ceres is best viewed at least an hour or so before sunrise to the east. Ceres is in the constellation of Gemini shining at magnitude 8.8.


Rises at 6:44 p.m. on the 1st and about 4:41 p.m. by month's end. Pluto is visible all night long, but is best viewed when it is highest in the sky about 6 hours after it rises. Pluto is in the constellation of Sagittarius shining at magnitude 14.2.

As always, good luck at spotting Neptune, Ceres and Pluto, a large telescope and dark skies will be needed.

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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 trains.

    Unfortunately, a waning gibbous Moon will obscure all but the brightest meteors, but that's no reason to not enjoy the Perseids this year as you may still see between 15 and 30 meteors per hour despite the Moon's glow.

    Meteor Shower Radiant Report

    For more information about Meteor Showers, visit Gary Kronk's Meteor Showers Online web page.

    Meteor Scatter (or Meteor burst communications) - "is a radio propagation mode that exploits the ionized trails of meteors during atmospheric entry to establish brief communications paths between radio stations up to 2,250 kilometres (1,400 mi) apart." Tune your shortwave or your HF amateur radio to 54.310 MHz SSB and see if you can hear any pings.

  • Comets

  • Comet PANSTARRS (C/2015 ER61) passes through the constellation of Taurus the Bull this month, shining diminutively around 9th magnitude. However, it should be fairly easy to spot, especially between August 14 through August 21 as Comet PANSTARRS passes within 1° of the Pleiades star cluster.

  • Comet Johnson (C/2015 V2) is passing from the constellation of Centaurus into Lupus shining around 8th magnitude. Comet Johnson is best viewed from southern latitudes.

  • Comet 71/P Clark passes through Scorpius shining around 10th magnitude. Again, southern observers may have a better chance to see this one.

  • For information, orbital elements and ephemerides on observable comets, visit the Observable Comets page from the Harvard-Smithsonian Center for Astrophysics.

    For more information about Comets, visit Gary Kronk's webpage.

  • Eclipses

    Solar Eclipses

  • Total Solar Eclipse occurs on the 21st. This eclipse passes across the entire continental United States, visible along a path from Oregon through South Carolina. Links and Information

    Lunar Eclipses

  • There is a partial Lunar Eclipse occurring on the 7th for observers in most of Europe, Africa, Asia and Australia.
  • Observational Opportunities

  • Enjoy Jupiter and Saturn in the evening.
  • Look for Venus in the morning skies before sunrise.
  • Try to spot Comets PANSTARRS, Johnson and Clark.
  • Try to catch some of the Perseids meteor activity all month.
  • Experience the Total Solar Eclipse on the morning of the 21st.

  • Asteroids

    (From west to east)
    • Hebe is in the constellation of Ophiuchus.
    • Julia is in the constellation of Pegusus just to the north of Neptune.
    • Iris is in the constellation of Aries just to the north of Uranus.
    • Pallas is in the constellation of Eridanus.

    • Information about the Minor Planets can be found at the Minor Planet Observer website.

    IOTA Logo

  • Information on various occultations can be found by clicking the IOTA logo.
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    Subscriber Gallery

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    Member Meteor Sightings

    This is a new section where I will post meteor, fireball, etc sightings that have been published on the American Meteor Society's web site. I want to make this an active section of the web pages and newsletter and would like to publish the links to member sightings. If you have any published sightings, please provide me with the links and I will post them here for all to enjoy.

    Event ID Date/Time Location Observer Link
    3587-2015 2015-11-22 17:38 MST CO Kevin S 3587aw
    3829-2015 2015-12-05 18:06 MST Highlands Ranch, CO Burness A 3829a
    3871-2015 2015-11-13 01:55 MST CO Charles N 3871a

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    Planetary/Lunar Exploration Missions

    (Excerpts from recent JPL mission updates)
    JPL Latest News
    The Latest from Space

    JPL Latest News

    Juno - July 12, 2017
    NASA's Juno Spacecraft Spots Jupiter's Great Red Spot

    Full Article & Images

    "Images of Jupiter's Great Red Spot reveal a tangle of dark, veinous clouds weaving their way through a massive crimson oval. The JunoCam imager aboard NASA's Juno mission snapped pics of the most iconic feature of the solar system's largest planetary inhabitant during its Monday (July 10) flyby. The images of the Great Red Spot were downlinked from the spacecraft's memory on Tuesday and placed on the mission's JunoCam website Wednesday morning."

    NASA's JunoCam website can be visited at:

    More information on the Juno mission is available at:

    The public can follow the mission on Facebook and Twitter at:

    Cassini - July 28, 2017
    Southern Auroras Over Saturn

    Full Article & Images

    "Cassini gazed toward high southern latitudes near Saturn's south pole to observe ghostly curtains of dancing light -- Saturn's southern auroras, or southern lights. These natural light displays at the planet's poles are created by charged particles raining down into the upper atmosphere, making gases there glow."

    Raw images are available at

    More information about Cassini is available at the following sites:

    Cassini Imaging Team - Archives from Dec. 2015 and earlier.

    New Horizons - July 19, 2017
    NASA's New Horizons Team Strikes Gold in Argentina

    Full Article & Images

    "A primitive solar system object that's more four billion miles (6.5 billion kilometers) away passed in front of a distant star as seen from Earth. Just before midnight Eastern Time Sunday (12:50 a.m. local time July 17), several telescopes deployed by the New Horizons team in a remote part of Argentina were in precisely the right place at the right time to catch its fleeting shadow -- an event that's known as an occultation."

    New Horizons gallery

    Find New Horizons in the iTunes App Store here.

    For more information on the New Horizons mission - the first mission to the ninth planet - visit the New Horizons home page.

    Dawn - May 16, 2017
    Movie Shows Ceres at Opposition from Sun

    Full Article & Images

    "NASA's Dawn spacecraft successfully observed Ceres at opposition on April 29, taking images from a position exactly between the sun and Ceres' surface. Mission specialists had carefully maneuvered Dawn into a special orbit so that the spacecraft could view Occator Crater, which contains the brightest area of Ceres, from this new perspective.

    A new movie shows these opposition images, with contrast enhanced to highlight brightness differences. The bright spots of Occator stand out particularly well on an otherwise relatively bland surface. Dawn took these images from an altitude of about 12,000 miles (20,000 kilometers)." A gallery of images can be found online.

    For more information on the Dawn mission, visit the Dawn home page.


    The MESSENGER mission is officially ended but there is a lot to learn about the planet closest to our Sun. Visit the new, updated MESSENGER website:

    for resources, to learn, and to explore.

    (Click Link above for Full Article & Images)


    "After more than 10 years in operation, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft impacted the surface of Mercury on April 30, 2015, at a speed of more than 3.91 kilometers per second (8,750 miles per hour), marking the end of operations for the hugely successful Mercury orbiter. At the MESSENGER Nears End of Operations media and public event, scientists and engineers discussed the mission's accomplishments, providing the top 10 scientific discoveries, as well as the technological innovations that grew out of the mission."

    The MESSENGER app is available for download from iTunes.

    For more information on the MESSENGER mission, visit the MESSENGER home page.

    Past, Present, Future and Proposed JPL Missions -

    Visit JPL's mission pages for current status.

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    Mars Missions

    Be A Martian

    Mars website mobile version is here!

    Mars on the Go! NASA Be A Martian Mobile App
    If you want the latest news as it happens, try our Be A Martian app.
    Download on Mobile Devices
    Android | iPhone | Windows Phone

    JMARS is an acronym that stands for Java Mission-planning and Analysis for Remote Sensing. It is a geospatial information system (GIS) developed by ASU's Mars Space Flight Facility to provide mission planning and data-analysis tools to NASA's orbiters, instrument team members, students of all ages, and the general public.

    Laboratory for Atmospheric and Space Physics

    "The Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder (CU) began in 1948, a decade before NASA. We are the world's only research institute to have sent instruments to all eight planets and Pluto. LASP is an affiliate of CU-Boulder AeroSpace Ventures, a collaboration among aerospace-related departments, institutes, centers, government labs, and industry partners."

    MAVEN - June 16, 2017
    1,000 Days in Orbit: MAVEN's Top 10 Discoveries at Mars

    Full Article & Images

    "On June 17, the MAVEN mission will celebrate 1,000 Earth days in orbit around the Red Planet. Since its launch in November 2013 and its orbit insertion in September 2014, MAVEN has been exploring the upper atmosphere of Mars. MAVEN is bringing insight to how the sun stripped Mars of most of its atmosphere, turning a planet once possibly habitable to microbial life into a barren desert world."

    Visit LASP and MAVEN for more information.

    Mars Science Laboratory - Curiosity - July 14, 2017
    Sol 1756: Closing time

    Full Article & Images

    "Today marked the last chance for us to reliably command Curiosity before she, and Mars, disappear behind the Sun for about three weeks. This made today's planning feel as if the Sun were setting on our normally active rover activities, akin to this Martian sunset image from 2015. MAHLI, APXS and ChemCam were already stored safely for the upcoming conjunction nap, leaving Mastcam and MARDI to collect a few last bits of science data for the GEO group. Mastcam acquired mosaics of the "Vera Rubin Ridge" above and in front of the rover, and of the workspace in front of the rover. Both mosaics not only inform us about the rocks around us, they will be used to plan activities right after we return from conjunction. Mastcam and MARDI will acquire images on sols 1757 and 1758 to look for wind-induced changes in the sands around the rover. These change detection images complement similar change detection images acquired at previous sand stops, revealing the dynamic nature of Mars. After imaging on Sol 1758, Mastcam will home her focus mechanisms and settle in for a well-deserved break."

    To follow the Mars Curiosity rover and NASA on Foursquare, visit: and

    For information about NASA's partnership with Foursquare, visit:

      Mars Rover Landing - Free for the Xbox 360 (requires Kinect)

      Visit the Mars Science Laboratory page.

    Mars Exploration Rover Mission (Spirit and Opportunity) - July 24, 2017

    SPIRIT UPDATE: Spirit Remains Silent at Troy - sols 2621-2627, May 18-24, 2011:

    "More than 1,300 commands were radiated to Spirit as part of the recovery effort in an attempt to elicit a response from the rover. No communication has been received from Spirit since Sol 2210 (March 22, 2010). The project concluded the Spirit recovery efforts on May 25, 2011. The remaining, pre-sequenced ultra-high frequency (UHF) relay passes scheduled for Spirit on board the Odyssey orbiter will complete on June 8, 2011.

    Total odometry is unchanged at 7,730.50 meters (4.80 miles)."

    OPPORTUNITY UPDATE: Opportunity Enters Automode During Solar Conjunction Pause in Commanding - sols 4793 - 4799, July 18, 2017 - July 24, 2017:

    "Opportunity is in Perseverance Valley on the west rim of Endeavour Crater and the mission is now in its solar conjunction communications blackout period. The position of Mars as viewed from Earth will remain very close to the sun until early August. In this geometry, the solar corona degrades radio communications between the two planets and restricts spacecraft communication.

    In advance of solar conjunction, we prepared two weeks of command sequences and stored them on Opportunity to keep the rover busy during the communication blackout. Although we are now in a moratorium on sending commands, we did receive a tiny amount of relayed Opportunity data on Sol 4797. Those limited data indicated that Opportunity is in automode, a state where no master sequence is running and the rover keeps itself safe while waiting further communication from ground control. We suspect that a warm reset of the rover's computer occurred during the Sol 4795 morning X-band communication session, halting the stored master sequence of commands.

    The vehicle is power positive, thermally stable and will continue to honor the scheduled X-band and UHF relay communication passes through the remainder of solar conjunction. As the rover is expected to remain safe and solar corona effects will all but prevent any confident commanding until after conjunction, the project's position is to let the rover remain in automode for the remainder of conjunction. Full investigation of the cause will have to wait until we can resume commanding of the rover.

    As of Sol 4793 (July 18, 2017), the solar array energy production was 332 watt-hours, with an atmospheric opacity (Tau) of 0.774 and a solar array dust factor of 0.534.

    Total odometry remains at 27.95 miles (44.97 kilometers)."

    Landing sites

    Visit the Mars Exploration Rover page.

    Mars Reconnaissance Orbiter Mission - July 14, 2017
    For Moratorium on Sending Commands to Mars, Blame the Sun

    Full Article & Image

    "This month, movements of the planets will put Mars almost directly behind the sun, from Earth's perspective, causing curtailed communications between Earth and Mars.

    NASA will refrain from sending commands to America's three Mars orbiters and two Mars rovers during the period from July 22 to Aug. 1.

    "Out of caution, we won't talk to our Mars assets during that period because we expect significant degradation in the communication link, and we don't want to take a chance that one of our spacecraft would act on a corrupted command," said Chad Edwards, manager of the Mars Relay Network Office at NASA's Jet Propulsion Laboratory, Pasadena, California."

    All of the HiRISE images are archived here.

    More information about the MRO mission is available online.

    Mars Odyssey Orbiter - January 04, 2017
    NASA Mars Odyssey Orbiter Resumes Full Operations

    Full Article and Images

    UPDATED Jan. 4, 2017, at 2 p.m. PST
    NASA's Mars Odyssey spacecraft has resumed full service following recovery after entering a safe standby mode on Dec. 26, 2016.

    The orbiter resumed communication relay assistance to Mars rovers on Dec. 30, 2016. Science observations of Mars by instruments on Odyssey resumed on Jan. 3, 2017, with its Thermal Emission Imaging System, and on the next day with its High Energy Neutral Spectrometer and the Neutron Spectrometer."

    Video - What might it look like if you were walking around on Mars?

    See the Mars As Art Gallery

    Daily Mars Odyssey THEMIS Images
    Can be found at the Thermal Emission Imaging System (THEMIS) website.

    The Odyssey data are available through a new online access system established by the Planetary Data System.

    Visit the Mars Odyssey Mission page.

    Journey to Mars - September 02, 2016
    InSight - Revealing the Heart of Mars
    NASA Approves 2018 Launch of Mars InSight Mission

    "InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) is a NASA Discovery Program mission that will place a single geophysical lander on Mars to study its deep interior.

    NASA is moving forward with a spring 2018 launch of its InSight mission to study the deep interior of Mars, following final approval this week by the agency's Science Mission Directorate."

    Learn more about the InSight Mission.

    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 and the Mars Exploration page.

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    Astronomy Links and Other Space News

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

    Green Laser

    Colorado Astronomy Links

    Radio Astronomy Links

    Other Astronomy Links

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    Astronomical Lexicon

    Definitions of astronomical terms. Many of the astronomical terms used in this newsletter are defined here.

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    UT Logo

    Read the Universe Today Newsletter by clicking on the logo.

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    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, and other astronomical sources that I have stashed on my bookshelves.

    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!

    More Acknowledgements and References

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