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Monday, June 17 2019 @ 10:01 pm EDT

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U. of A. Support of Nasa Hera Project

General NewsLocal journalists report that Derek Sears and his team at the University of Arkansas are among the leading contenders for the $450-mm NASA Hera project. This is a proposed mission to retrieve actual samples of an asteroid and return to Earth. I will contact Sears and find out if there is news that can be shared with the AOAS membership about this exciting mission. If they prevail in their bid, it appears that Fayetteville would become the brain-center for this major NASA project.
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AOAS to Seek Funding for Bifilar Micrometer

Chart RoomColeman Observatory would be a great place to begin a program dedicated to the study of binary stars, more popularly referred as "double stars". In order to perform proper measurements of binary star systems, a professional-quality bifilar micrometer would be required, just exactly the kind that is manufactured by Van Slyke Engineering (VSE). The cost will be between $2000 and $2500 for the micrometer we'd like to have, and I believe this should be our newest project to raise the funds needed for our own bifilar micrometer during 2006.

The VSE "NeedleEye" digital bifilar micrometer. Paul Van Slyke Engineering produces a limited number of high-quality, precision bifilar micrometers for sale to amateur astronomers and private observatories. The digital model shown here retails for $2450, but during the current sale, the price has been reduced to $1950. AOAS hopes to raise the funds needed to buy one of these professional-level instruments in 2006, to begin our own binary star program.
Binary, or double stars, are two or more stars which appear close to one another in our telescopes. Double stars can simply be two stars aligned such that they only "appear" to be a true pair, but in reality the two stars may be quite far apart with one star being much closer to us than the other. Such chance line-of-sight alignments of stars is not what a program of binary star study is about.

True binary stars are pairs of stars that share a common center of gravity, and are bound together by gravity throughout time, forever locked in a spiral dance whereby they actually orbit each other. The only accurate way to measure the masses of stars is by carefully measuring the changing positions of the two stars over long periods of time. Binary systems may complete each orbit in as few as 5 to 10 years, or they may take as long as 20 to 50 years to do so. Such measurements are made by using an instrument known as a bifilar micrometer.

A bifilar micrometer is an instrument which has an illuminated reticle etched into a glass as a "crosshair", with a second single-line reticle that can be moved, with exquisite precision, and be placed over the secondary star of a pair allowing for their separation to be recorded with extreme accuracy. The crosshair reticle can be rotated so that one of the illuminated lines might be oriented to celestial north. This thereby allows the angle of a binary pair to be determined as measured in a clockwise direction away from 0 degrees, which begins at true north. Such instruments are not a common item for sale to amateur astronomers, and those with the quality of workmanship desireable for high-quality measurements are not cheap. A very limited number of companies offer such instruments, and among the best in the world today, are those available from Van Slyke Engineering.

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Mars Night at Coleman Observatory Oct 29th

Coleman ObservatoryUPDATE: October 29th saw upwards of 85 visitors at Coleman Observatory to enjoy views of Mars. Telescopes of every type and from 5" diameter up to the 14" aperture of our primary instrument were used, and will again be in use for the next Mars Star Party on November 5th! Come to Coleman Observatory and join us before Mars begins to rapidly shrink in size after mid-November.

Mars marks its closest point to Earth since 2003 on Saturday, October 29th, at a distance of "merely" 43,000,000 miles away. Join members of AOAS at our Coleman Observatory located 8 mi. NW of Van Buren for the best views of the mythological Roman "God of War" until 2018!

AOAS member Jeff Treshnell captured this image of Mars through his telescope in 2003. This is very similar to what the view of Mars will look like through the telescopes at Coleman Observatory on the weekends of October 29th and November 5th. The public is invited to both events, and as always there are NO FEES to share the views of our universe with us. UPDATE: Visitors to Coleman Observatory on Oct 29th saw virtually the exact same view of Mars as is depicted here. If you missed it last Saturday, join us again THIS Saturday, Nov 5th.
It's a fact, Mars is as close to Earth as it'll be for the next 13 years on the 29th of October and the public is invited to come out and see it with us through our telescopes. The viewing begins at sunset that evening with brilliant Venus in the SW skies. Then we'll watch as Mars slowly creeps above the eastern horizon shortly after sunset. By 7:45, Mars will be high enough to view through most of the telescopes we have on site, but as the evening progresses and Mars continues rising, the views will just get better and better.

The reason for this is simple. Low on the horizon, we view objects through the thickest part of Earth's atmosphere. You are literally seeing every object near the horizon through a couple hundred miles of haze, water vapor, pollution, etc. The best views of a planet like Mars comes after it has risen at least 30 degrees or more above the horizon where the atmosphere is less than 40 miles thick.

Between there and the time when it reaches a point overhead known as the zenith, you'll see the most detail available through whatever size and type of telescope you're viewing with. The best views of Mars will be between around 9:00 p.m. and midnight. For any night owl visitors who stay even later, those great views will continue until as late as 3:00 a.m. when Mars once again begins to sink into the thicker parts of our atmosphere in the western sky.

Mars will be well placed for viewing from mid-October through late November. For this reason, AOAS and Coleman Observatory will host a second public night on November 5th, the Saturday after the 29th. This will give everyone ample opportunities to come and view Mars at its best during this apparition.

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Where No Spacecraft Has Gone Before

NASA Space Placeby Dr. Tony Phillips

Voyager 1, after 28 years of travel, has reached the heliosheath of our solar system. (Click image for larger view.)
In 1977, Voyager 1 left our planet. Its mission: to visit Jupiter and Saturn and to study their moons. The flybys were an enormous success. Voyager 1 discovered active volcanoes on Io, found evidence for submerged oceans on Europa, and photographed dark rings around Jupiter itself. Later, the spacecraft buzzed Saturn’s moon Titan—alerting astronomers that it was a very strange place indeed! —and flew behind Saturn’s rings, seeing what was hidden from Earth.

Beyond Saturn, Neptune and Uranus beckoned, but Voyager 1’s planet-tour ended there. Saturn’s gravity seized Voyager 1 and slingshot it into deep space. Voyager 1 was heading for the stars—just as NASA had planned.

Now, in 2005, the spacecraft is nine billion miles (96 astronomical units) from the Sun, and it has entered a strange region of space no ship has ever visited before.

"We call this region ‘the heliosheath.’ It’s where the solar wind piles up against the interstellar medium at the outer edge of our solar system," says Ed Stone, project scientist for the Voyager mission at the Jet Propulsion Laboratory.

Out in the Milky Way, where Voyager 1 is trying to go, the "empty space" between stars is not really empty. It’s filled with clouds of gas and dust. The wind from the Sun blows a gigantic bubble in this cloudy "interstellar medium." All nine planets from Mercury to Pluto fit comfortably inside. The heliosheath is, essentially, the bubble’s skin.

"The heliosheath is different from any other place we’ve been," says Stone. Near the Sun, the solar wind moves at a million miles per hour. At the heliosheath, the solar wind slows eventually to a dead stop. The slowing wind becomes denser, more turbulent, and its magnetic field—a remnant of the sun’s own magnetism—grows stronger.

So far from Earth, this turbulent magnetic gas is curiously important to human life. "The heliosheath is a shield against galactic cosmic rays," explains Stone. Subatomic particles blasted in our direction by distant supernovas and black holes are deflected by the heliosheath, protecting the inner solar system from much deadly radiation.

Voyager 1 is exploring this shield for the first time. "We’ll remain inside the heliosheath for 8 to 10 years," predicts Stone, "then we’ll break through, finally reaching interstellar space."

What’s out there? Stay tuned…

For more about the twin Voyager spacecraft, visit voyager.jpl.nasa.gov. Kids can learn about Voyager 1 and 2 and their grand tour of the outer planets at spaceplace.nasa.gov/en/kids/vgr_fact3.shtml.
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AOAS Member Mike Holloway Contributes to Deep Impact

Astro ImagingMike Holloway observes and images from his home observatory north of Van Buren, Arkansas. With his 4" Takahashi FSQ-106 refractor and an SBIG ST-2000 CCD camera piggybacked on a Meade fork mounted SCT, he regularly submits images that garner world recognition. One of his most impressive feats to date is to have his image of Deep Impact Comet 9P/Temple1 from July 29, 2005 shown on the Deep Impact website. He has actually made quite a number of submissions to the overall effort on Deep Impact.
Periodic Comet 9/P Temple 1 on July 29, 2005. The comet has settled back down from it's flare-up just before, during and immediately after the Impactor craft slammed into the leading edge of Temple 1 on the evening of July 3-4 just three weeks earlier. Mike tracked on the comet making the stars trail in this image which appears in the Deep Impact website.

Mike loves comets! * That's what I said in the first article I wrote about him many months ago, and he hasn't slowed down one iota in his quest to image every available comet that swings around the Sun if at all possible, and there aren't very many that he misses. I just received this notice today about his image from July 29 appearing on the Deep Impact website and wanted to once again brag a little on the most successful astrophotographer in AOAS!

Observations of Temple 1 were made by amateur and professional astronomers from around the world during this historic first-of-its-kind mission from NASA. The Deep Impact website lists some impressive numbers of observers as well as their inclusion of Mike's image which they chose to use for a comparison to another set of four images. (To go directly to this page) Click here

I believe that Mike Holloway is in the process of making quite a name for himself in the world of astrophotography. I encourage everyone to leave a comment on Mike's achievements by clicking on "comment" at the bottom of this story. Whether you're an AOAS member, or a visitor from another country, please help us all show how much we respect Mike's work and how proud we are that he's one of our own! Make a comment now.

*Click on that first statement to see my first article on Mike.

"Comets on the Doorstep...." Here is another AOAS web story with more images and LOTS of links to Mike's and other comet watchers imaging handywork from around the world. ENJOY!
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Congratulations, It’s Twins!

Lunar & PlanetaryThe European Southern Observatory Very Large Telescope has discovered an asteroid with TWO orbiting moonlets, a first for any known asteroid. The Yepun instrument of the VLT facility made the historic find by utilizing the adaptive optics system instrument known as NACO. Results were published in the August 11 issue of the Journal Nature.

Discovered in 1866, asteroid 87 Sylvia, named for the mythological mother of the founders of Rome, now reveals her twin sons, Romulus and Remus.
As though they were technicians conducting an ultrasound examination of a fetus, a surprise awaited observers using the 8.2 meter Yepun telescope at the European Southern Observatory in Cerro Paranal, Chile. A team led by Franck Marchis of University of California Berkeley and co-discoverers Pascal Descamps, Daniel Hestroffer, and Jerome Berthier of the Observatoire de Paris, France, had been using the telescope to observe asteroid 87 Sylvia to check for moonlets circling about the main asteroid. Measurements had previously indicated that 87 Sylvia was an asteroid with one small companion in 2001 after work done by Mike Brown and Jean-Luc Margot at the Keck telescope in Hawaii.

Marchis and colleagues made 27 observations with the huge 8.2 meter Yepun telescope during a two-month period. On every image the known companion moonlet was seen allowing for that object's precise orbital elements to be determined, but 12 of those images revealed a separate, smaller companion orbiting closer in towards the main asteroid. What was once a single moonlet, is now twins.

The 87th asteroid discovery, 87 Sylvia has been determined to be a huge pile of rubble loosely joined together by a compilation of debris giving the overall appearance of a potato shaped asteroid. It would seem that at some time in Sylvia’s ancient past, something struck her with enough force to completely shatter her into a pile of debris, of which the attendant moonlets may simply be left-over material that didn't rejoin the main mass. This asteroid has a density estimated to be only 20% that of liquid water, and could be up to 60% empty space.
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Improbable Bulls-Eye

NASA Space Placeby Dr. Tony Phillips

Comet Tempel 1, as seen by the Deep Impact impactors camera. Three last-minute AutoNav-controlled impact correction maneuvers enabled the Impactor to hit the bulls-eye.
Picture this: Eighty-eight million miles from Earth, a robot spacecraft plunges into a billowing cloud almost as wide as the planet Jupiter. It looks around. Somewhere in there, among jets of gas and dust, is an icy nugget invisible to telescopes on Eartha 23,000 mph moving target.

The ship glides deeper into the cloud and jettisons its cargo, the "impactor." Bulls-eye! A blinding flash, a perfect strike.

As incredible as it sounds, this really happened on the 4th of July, 2005. Gliding through the vast atmosphere of Comet Tempel 1, NASAs Deep Impact spacecraft pinpointed the comets 3x7-mile wide nucleus and hit it with an 820-lb copper impactor. The resulting explosion gave scientists their first look beneath the crust of a comet.

Thats navigation.

Credit the JPL navigation team. By sending commands from Earth, they guided Deep Impact within sight of the comets core. But even greater precision would be needed to strike the comets spinning, oddly-shaped nucleus.

On July 3rd, a day before the strike, Deep Impact released the impactor. No dumb hunk of metal, the impactor was a spaceship in its own right, with its own camera, thrusters and computer brain. Most important of all, it had "AutoNav."

AutoNav, short for Autonomous Navigation, is a computer program full of artificial intelligence. It uses a camera to see and thrusters to steerno humans required. Keeping its "eye" on the target, AutoNav guided the impactor directly into the nucleus.

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Name a Star; Buy a Star.... Buyer Beware!

Myths & Legends
Can a STAR be Sold?
Can a STAR be Named?
Before you "buy a star" OR "name a star", understand what it is you're buying. Stars are not "named" or "sold" and the companies and/or individuals that advertise to an unsuspecting public that they can "buy" or "name" a star do so with the utmost incredulity.

The MOST outrageous thing I've ever seen in the hobby of amateur astronomy, is the buying or naming of stars for profit. There are places in the world, be they so-called "companies" or individuals, that will SELL anyone a star for a price. They know full well that they can't actually sell stars, and for an unsuspecting public that doesn't understand any better, it's caveat emptor....BUYER BEWARE!

Amateur astronomers around the world have encountered the problem involving the "sale" of stars. Stars are NOT sold, nor are they named for people or by people. The stars in the sky do carry one or more designations assigned by institutions that are recognized as having the ability to do this. Astronomers and astrophysicists establish the criteria for assigning different designations to stars through an organization known as the International Astronomical Union, and the entire world of professional Astronomy and Astrophysics accepts these legitimate designations.

Many of the brighter stars in the sky do have names. Accepted star names are either Greek, Arabic, or Latin in origin. Let's take for instance, the star Mizar in the constellation of Ursa Major. Mizar is the middle star in the handle of the Big Dipper, which is an asterism. An asterism is an easily identifiable group of stars which resemble something familiar. The seven stars of the Big Dipper are just the brightest of all the stars that comprise the complete constellation of Ursa Major, which depicts a large bear. Consider all the following things that involve the star Mizar and its many proper designations.

Mi 'zar is an Arabic word which translates to "girdle" as in the middle of the handle. Many stars in the night sky have Arabic names, and that's another complete story altogether. But Mizar has other official designations, such as Zeta Ursae Majoris (latinized version of its Bayer* designation), HIP 65378** (its designation in the Hipparchos catalog), and a few others. All these designations are different ways of referring to the exact same star, the star that resides at 13h 23' 55", by +54d 55' 31.5" on the celestial sphere. These coordinates may be considered extensions of map coordinates that depict latitude and longitude on a world map.
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Mars or Bust - Mars Reconnaissance Orbiter

Lunar & Planetary
An Atlas V rocket blasts off from Cape Canaveral Air Station at approximately 7:43 a.m. on August 12, 2005. Its payload is the Mars Reconnaissance Orbiter, and by November 2006, it will begin the most highly-detailed, in-depth study of Mars yet conceived.
Rising into the air in the morning sun, an Atlas V rocket lifts off for the Red Planet. In the nose cone, the largest spacecraft ever sent to Mars huddles under the shroud, wings folded, antennae tucked tightly away. It will arrive in March 2006, seven months from now, and then spend another six months gradually circularizing its orbit until its 25-month science mission can begin. That mission is a prestigious one, but it will continue to serve future missions to Mars by using its sophisticated high-speed communications system to relay data back-and-forth at more than 10 times the rate of any other communications system to date. Say hello to the fast-talking new kid in orbit, the Mars Reconnaissance Orbiter, or MRO.

It needed a heavy-lift rocket to get off the Earth and send it some 70 million miles towards the planet Mars. As the hours passed on launch day, big grins pervaded the control room as item after item on the checklist were crossed-off satisfactorily. So far, so good. MRO is now in the "cruise" phase of its mission.

It's dimensions are impressive standing 21 feet tall with a 10 foot-diameter communications antenna.
Aerobraking will take MRO skimming just above the thickest part of Mars' atmosphere numerous times, each pass slowly refining the shape and altitude of its orbit until it becomes nearly circularized by September 2006.
When its solar panels are fully extended they will be 45 feet wide from tip-to-tip. The entire craft weighs a little over 4,800 lbs, and nearly half of that weight at launch will be the fuel needed for use in the 20 on-board thrusters that will control it while in orbit. MRO was built by Lockheed Martin Space Systems in Denver, CO.

This mission to Mars will seek to establish the following goals. 1) Characterize the present climate of Mars. How exactly does the climate change from season-to-season and from year-to-year. 2) Characterize Mars atmosphere and monitor its weather. 3) Investigate complex terrain on Mars and identify water-related landforms. 4) Search for sites showing stratigraphic or compositional evidence of water or hydrothermal activity. 5) Probe beneath the surface for evidence of subsurface layering, water and ice, and profile the internal structure of the polar ice caps. 6) Identify and characterize sites with the highest potential for future landings on the surface to include sites from where sample return missions might land. 7) Relay scientific information to Earth from current and future Mars surface missions.

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Newest Weather Sentry Takes Up Watch

NASA Space Placeby Patrick L. Barry

NOAA-18, the newest in a long line of weather and environmental satellites, launched May 20, 2005.
Today, we've become accustomed to seeing images of the Earth's swirling atmosphere from space every night on the evening news. Before 1960, no one had ever seen such images. The first-ever weather satellite was launched that year, kicking off a long line of weather satellites that have kept a continuous watch on our planet's fickle atmosphere45 years and counting! The high-quality, extended weather forecasts that these satellites make possible have become an indispensable part of our modern society, helping commercial aircraft, recreational boaters, and even military operations avoid unnecessary risk from hazardous weather. But satellites don't last forever. Parts wear out, radiation takes its toll, and atmospheric drag slowly pulls the satellite out of orbit. Many weather satellites have a design life of only 2 years, though often they can last 5 or 10 years, or more. A steady schedule of new satellite launches is needed to keep the weather report on the news each night. In May 2005, NASA successfully launched the latest in this long line of weather satellites. Dubbed NOAA-N at launch and renamed NOAA-18 once it reached orbit, this satellite will take over for the older satellite NOAA-16, which was launched in September 2000. NOAA always keeps at least two satellites in low-Earth orbit, circling the poles 14 times each day, explains Wilfred E. Mazur, Polar Satellite Acquisition Manager, NOAA/NESDIS. As Earth rotates, these satellites end up covering Earths entire surface each day. In fact, with two satellites in orbit, NOAA covers each spot on the Earth four times each day, twice during the day and twice at night, Mazur says.

By orbiting close to Earth (NOAA-18 is only 870 km above the ground), these low-Earth orbit satellites provide a detailed view of the weather. The other type of weather satellite, geosynchronous, orbits much farther out at 35,786 km. At that altitude, geosynchronous satellites can keep a constant watch on whole continents, but without the kind of detail that NOAA-18 can provide. In particular, low-Earth orbiting satellites have the ability to use microwave radiometers to measure temperature and moisture in the atmospheretwo key measurements used for weather prediction that, for technical reasons, cannot be sensed by distant geosynchronous satellites. With NOAA-18 successfully placed in orbit, the 45-year legacy of high-tech weather forecasts that we're accustomed to will go on.

Find out more about NOAA-18 and the history of polar-orbiting weather satellites at http://goespoes.gsfc.nasa.gov/poes. For kids and anyone else curious about the concept, the difference between polar and geosynchronous orbits is explained at http://spaceplace.nasa.gov/en/kids/goes/goes_poes_orbits.shtml .

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

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