http://www.rfo.org

Spring 2015 Volume XVIII Number 2

July 11, SaturdayPublic Solar Observing 11 am – 3 pmPublic Observing Night 9 pm

Evening public viewing is $3 per adult, 18 years or older, plus $8 per car parking fee. Donations accepted. Dress for cold nights! For current observatory information call: (707) 833-6979.

Public Events at

(turn to CONTENT on Page 7)

RFO Classes (see Page 3)

Where I Am Perfectly Content by Carlos Anicetti

Night Sky Spring Series

July 7 & 14August 11 & 18Be sure to check out our new website at http://www.rfo.org for more interesting astronomical events and information.

April 14

June 13, SaturdayPublic Solar Observing 11 am – 3 pmPublic Observing Night 9 pm

May 16, SaturdayPublic Solar Observing 11 am – 3 pmPublic Observing Night 9 pm

June 9 & 16Night Sky Summer Series

April 25, SaturdayPublic Solar Observing 11 am – 3 pmPublic Observing Night 9 pm

May 12 & 19

June 20, SaturdayPublic Solar Observing 11 am – 3 pmPublic Observing Night 9 pm

Robert FergusonObservatory

July 18, SaturdayPublic Solar Observing 11 am – 3 pmPublic Observing Night 9 pm

As I finish my senior year in high school, I would like to share the personal essay that I submitted with my college ap-plications. The prompt was: Describe a place or environment where you are perfectly content. What do you do or experience there, and why is it mean-ingful to you? I would like to express my gratitude to everyone at the RFO for the opportunity to be part of this wonderful organization and for all of your support. I extend special thanks to my mentor Steve Smith and to the entire CCD team. The Observatory has played a key role in my finding my passion for astrophysics and being accepted by my first choice university, Princeton, for which I will always be grateful.

Although it was currently warm, this would change quickly enough. For that reason, my long brown coat — the one made of heavy wool, which goes down to my ankles — was spread out on the chair behind me, along with my woolen scarf and dark brown gloves. The sky was darkening, but it was still slightly too bright to start imaging. I could make out Arcturus and Spica without much difficulty, but other stars and their re-spective constellations were still washed out by the glow left by the setting sun. This was my 28th night observing this supernova, and experience told me that it would be at least thirty minutes before I could start imaging. I set the camera to its cooling cycle and went to get a cup of coffee. When I returned, I

could make out the brightest stars in Ursa Major, my target constellation. It was January, near the winter solstice, and I had plenty of darkness ahead for imaging. I chose Mizar as a guide star and checked the temperature of the telescope’s camera — -25° C, it would reach the required -30° C by the time my preparations were finished. The first cold wind of the night began to blow and I pulled on my coat, settling in for the next twelve hours. It was then that the feeling struck.

As always, I was excited to be stargaz-ing. However, this particular night came with an altogether different realization. The object of my research that night, SN2014J in M82, was a type Ia super-nova, and it would completely fade away by the next weekend. No matter what happens, no matter where I go in life or what I do, 28 observations of SN2014J from a young amateur astronomer in California will forever be in the data banks of the American Association of Variable Star Observers, there for any-one to analyze. I was contributing to the understanding of the universe.

I am a volunteer docent at the Robert Ferguson Observatory (RFO), a small all volunteer institution. There I operate a 14-inch computer guided CCD tele-scope and give presentations during public and private events. I am allowed

Focused

A quarterly newsletter published by:

The Valley of the Moon Observatory Association

P.O. Box 898Glen Ellen, CA 95442

707.833.6979www.rfo.org

Editor: D. Braud

Publisher: Robert Davis

Contributors: Robert Davis Loren Stokes Jack Welch Carlos Anicetti George Loyer

SubscriptionsFill out & mail form on back page or online at

www.rfo.org

AdvertisingContact the editor, D. Braud:

dbraud@rfo.org

Submission GuidelinesUnsolicited submissions are welcome and will be published at the discretion of the editorial

staff. Send submissions to the editor:dbraud@rfo.org

VMOA Mission StatementThe VMOA is a group of volunteer amateur and professional astronomers organized as a non-profit association to provide educa-

tional programs about science and astronomy for students and the public. To that end,

the VMOA operates the Robert Ferguson Observatory in Sugarloaf Ridge State Park in

association with California State Parks.

VMOA Board of Directors

President: Robert DavisVice President: Steve SmithTreasurer: Lesley GaudiosiSecretary: George LoyerMembers: Colleen Ferguson Mark Hillestad Dave Kensiski Larry McCune Greg Reynolds Bill Russell Gordon Spear

President’s Message

(turn to PRESIDENT on Page 6)

Page 2 Sp r ing 2015

By Robert Davis

My cousin has a place in the foothills just outside Nevada City. The western view stretches clear to the coastal mountains and the sunsets can be quite spectacular. When she described this place to me a few years ago I suggested it might be fun to pay her a visit some time and bring my telescope. As we talked more about it my thoughts went from showing my cousin some cool stuff in my telescope to providing her and her friends the RFO experience. It has become an annual event, more or less, and as I write this article, the last one was just a week ago.

Obviously I can’t provide the full experience of an observatory with three great telescopes and a team of really great docents but here is what I can do. I take a Friday off work and hit the road so that I reach Auburn at lunch time. I have lunch at Mel’s Diner (The Original Mel’s) and listen to classic oldies while I’m munching a burger and fries. I was in for a rude awakening this trip, for as I was listening to groups like The Drifters, The Four Tops, and Creedence Clearwater, out of nowhere I was hit with music from my high school years. It was ok when “the oldies” was the music my parents listened to as teens, but when did the music of my youth become old? But I digress.

When I finish lunch I call my cousin to let her know I’m on the final stretch and she comes out to greet me when I pull into her driveway. After some

refreshments and catching up she starts dinner and I start setting up. As more friends start showing up she wonders where everybody is going to park. It’s starting to feel more like RFO already. For the folks who arrive before sunset I have my Coronado PST so we can view the Sun. This last trip I added an extra bonus of playing my Great Highland Bagpipe as the Sun went down. The few that were there seemed to really enjoy that. Maybe I should start the tradition up at RFO but who would take my place if I couldn’t be there?

So we’ve got solar viewing and park-ing problems sorted out. Next we need to wait for the sky to get dark enough to do some deep space viewing, so I give them a presentation. I bring up a computer and a projector and I give them a show. We project onto a white sheet pinned to a barn door, so the image is smaller than the RFO classroom’s screen, but it is just as much fun to present and the much smaller group enjoys and appreciates it just as much as the large crowds on a public star party night.

As the skies get dark enough I start out with a sky tour. If we are lucky there is a planet or two (or three) to check out and then I move on to the deep space objects. We continue view-ing until the crowd starts to run out of steam. As people start to leave they say their goodbyes and I tend to get many “thank you so much for doing this” and “that was awesome” and the like. My favorites are, of course, the “Oh Wow!” and “This is the first time I’ve ever seen Saturn’s rings (or Jupiter’s moons) in a telescope”. Sharing the telescope is great fun but I’m so glad RFO has showed me the way to provide an even deeper and richer experience. Especially since it is only Friday night and I get to do it all again the next night for a new set of friends.

Now no way am I even hinting at the mere suggestion of even thinking about doing two public nights back to back at RFO. And I am exceedingly grateful

Spr ing 2015 Page 3RFO 2015 Class Schedule

By Robert Davis

Night Sky ClassesEach class includes a lecture on the constellations of the season, their history and mythology, and how to find objects within them. Learn the bright stars, deep-sky objects, and visiting planets of the night skies. After each presentation (sky conditions permitting), you will enjoy a review of the constellations in the actual night sky and learn how to find them for yourself. The constellations, and the objects within them, will be viewed through binoculars and telescopes, including the Observatory’s 24-inch reflecting telescope, until or beyond 10:30 pm (depending upon interest and enthusiasm).The continuing Spring Series classes will be held on Tuesday, April 14, and May 12 & 19 at 7:30 pm. The upcoming Summer Series classes will begin on Tuesday, June 9 at 8 pm.The Summer Series classes continue on June 16, July 7 & 14, and August 11 & 18Fee: $75 for 6-class series or $23 for a single classE-mail: nightsky@rfo.org to reserve a space in this popular classLook for more information about RFO’s Night Sky Classes online at http://www.rfo.org

Observing LabsAn intensive telescope observing session after a brief presentation on the night’s theme. Handouts/Observing lists provided. Attendance limited to 6.Fee: $30. For reservations, email: nightsky@rfo.org The next scheduled Observing Lab, ‘Star Death: The End of Stellar Fusion’, is Saturday, September 12 at 7:00 pmLook for more information about RFO’s Observing labs online at http://www.rfo.org

Dwarf Planets, Minor Worlds, and Asteroids, Oh My!by George Loyer

Milestone Reached: Project 40

(turn to OH MY! on Page 7)(turn to MILESTONE on Page 5)

Project 40 is nearing completion as the team working on the new large telescope for the Robert Ferguson Observatory an-nounced that the mirror passed a star test. The visual check of the mirror’s figure by observing a star is the final step in the mirror fabrication after years of figuring and testing with the group’s Bath interferometer in Steve Follett’s shop. Team members reported round, out-of-focus star images (both in-side and outside of focus) and excellent views of Jupiter, its bands, and its pinpoint moons, even using an uncoated mirror.

Larry McCune has begun meetings with an engineer from JDSU to plan work and confirm schedules for getting the large mirror aluminized in the Santa Rosa JDSU mirror coating facility. Three years ago the VP of Research and Development at JDSU, Fred Van Milligen, reached out to the team after seeing a Press Democrat article on the project, and suggested that JDSU could coat the mirror at no cost to VMOA. He has signaled this may still be possible. Larry, along with Steve and Mark Hillistad, are working out the details with engineer Charles Kennemore. At this early point in the process, the schedule is fluid, but it is possible that the coating will be on the mirror by the end of June.

In the intervening time, the team has adopted a new optical design that makes the telescope shorter and still meets the requirement that most observers be able to look through the

On January 1st, 1801 an Italian monk by the name of Giuseppe Piazzi (1746-1846) discovered a new planet orbiting the Sun somewhere between Mars and Jupiter. He named it Ceres. By the end of 1851, 14 similar objects had been discovered and Ceres was reclassified as an asteroid. In 2006 it was given the title of Dwarf Planet. Maybe some Pluto fans will feel a little better knowing that their favorite once upon a time planet was not the first to be downgraded - if you see being reclassified as a Dwarf Planet as a downgrade, but that is a debate for another time. For now, NASA has placed a spacecraft in orbit around Ceres and that is a great accom-plishment. But in a similar fashion as Rosetta’s journey to 67P/Churyumov-Gerasimenko, I am just as impressed with Dawn’s journey to Ceres.

Ceres is the smallest of the known objects classified as dwarf planets but it is the most massive object in the asteroid belt. The second most massive object out there is Vesta. It was discovered by a German astronomer, Heinrich Wilhelm Olbers (1758-1840), on March 29, 1807. Vesta is classified as a Minor World, and no, I don’t know the difference between a Dwarf Planet and a Minor World. I’m sure there is a defini-tion, as well as a bad joke, out there somewhere but for now let’s get back to Dawn. Before its meet up with Ceres, Dawn was in orbit around Vesta and that is the amazing bit. Dawn

Page 4 Sp r ing 2015

Watching the 2015 Spring Skyby Jack Welch

I’ve written a lot about Jupiter in the last two newsletters since it was at both opposition and equinox this winter, giving us a season of mutual satellite events in addition to all of its usual delights. Jupiter completes its current display this spring, also ending these mutual satellite events for another 6 years by the end of June. (Details on those and more can be found using the “What’s Up in the Night Sky” link on the RFO website.) Dominant in the evening sky all spring in Leo, Jupiter ends retrograde motion on 4/8 and will approach Venus in the west during late June, the two coming VERY close to each other on the evening of 6/30. Especially interesting is that the disk size of Venus, in crescent phase, will be almost identical to that of Jupiter that evening (both 32”). And Jupiter will treat us to one more double shadow transit on the evening of 6/3. Start observing by 9:30pm in twilight when Io and its shadow will already be in transit. Ganymede’s shadow starts to transit at 9:58. Io’s transit ends at 10:05 and its shadow transit ends at 11:13. Ganymede’s shadow will still be in transit when Jupiter sets at about 12:30am. Apart from these special events, the moon will be near Jupiter around 3am on 3/30, around 11pm on 5/23 and around 10pm on 6/20.

Meanwhile, Saturn, in Libra, follows Jupiter by about 6 sky hours, rising around midnight in late March. It will be rising before 9pm when it reaches opposition on 5/22. (The disk size will be 19”, the rings 42” across and with a tilt of 24.4°.) So all spring and early summer are great for Saturn observing. The moon is near Saturn around 5am on 4/8, 4am on 5/5, 9pm on 6/1 and 10pm on 6/28.

Venus reigns as “Evening Star” all spring reaching greatest elongation east on 6/6. When we see Venus or Mercury in the evening sky, they are trailing the earth but catching up with us on their faster “inside track” orbits. They start in gibbous phase, wane to quarter phase around greatest elongation, and then finish up their evening apparitions in crescent phase. You can observe this change in Venus this spring and notice how its disk size increases as it gets nearer to us and the phase decreases. Binocular observers may be able to detect hints of Venus in crescent phase during late June and July. As mentioned above, Jupiter comes very close to Venus on 6/30. The crescent moon joins Venus on the evenings of 3/22, 4.21, 5/21 and 6/19.

Mercury provides its best evening apparition of 2015 from 4/22 to 5/18, reaching a maximum altitude 45 minutes after sunset of 11° on 5/5. Greatest elongation east is on 5/6. Observing the phase changes of Mercury is more challenging, given its small size and low altitude (and thus greater distortions from looking through earth’s atmosphere), but is possible. On 4/22, itself, Mercury will provide a last chance to glimpse Mars. Start looking for Mercury 35 to 40 minutes

after sunset (about 8:30pm near RFO), and about 5° above the horizon 20° north of due west. Mercury will be quite bright but use binoculars to help in the twilight glow. Mars will be about 1° to the south (left) of Mercury and slightly lower and binoculars will be essential to spot the 2 magnitudes dimmer red Mars. The pair should be viewable for at least 15 minutes if you have an unobstructed horizon. After this, Mars will not be visible again until it rises in the predawn twilight late this summer.

In addition to the Moon and planet pairings mentioned above, the moon is in a series of close encounters with the bright red star Aldebaran in Taurus. These produce lunar occultations of Aldebaran for people who are at the right places at the right time. That won’t happen for us until December. But we can catch the moon very near Aldebaran around 11:30pm on 3/24 and again during the daylight around 10am on 4/21. Use binoculars to enjoy these close encounters. (For safety, stand in an area shaded from the sun for the daylight event.) Those up early that morning can catch the pair in the predawn sky.

There will be a total lunar eclipse on the morning of 4/4. Officially beginning at 2:02am, darkening won’t be obvious until around 2:40 or so. The moon enters earth’s umbra at 3:16, with totality being very brief: from 4:58 to 5:02. In other words, this very nearly a partial eclipse. This means that the “Japanese Lantern” illusion just before and after totality should be long lasting, with just a bit more than 4 minutes between the two events. Twilight begins at 5:20, and the moon exits the umbra at 6:44, just minutes before sunrise and moonset!

For those wishing to view very thin crescent moons after sunset, we have three opportunities: a 2.6% crescent 7° high 11° north of west 40 minutes after sunset (or at 8:30pm near RFO) on 4/19; a 5.1% crescent about 42 minutes after sunset (or at 9:00pm near RFO) on 5/19; and a 3.0% crescent 5° high 17° north of west about 24 minutes after sunset (or at 9:00pm near RFO) on 6/17.

There will be easily observed bright star occultations this spring: lambda Geminorum on 3/28(a.m.); alpha Cancri (Acubens) on 3/30(a.m.); 75 Leonis on 4/2(a.m.); and 79 Leonis on 5/26(p.m.). Details of these events are available on the RFO website.

Finally, conditions are favorable this year for viewing the Lyrid Meteor Shower. While the peak is predicted to be around 4pm on 4/22 for our area, we can still expect to see about 10 meteors per hour or so after about 12:30am on 4/23. It would also be worth watching for Lyrids after 11:30pm on 4/21.

Spring officially ends with the Summer Solstice at 9:38am PDT on June 21 this year.

Spr ing 2015 Page 5

eyepiece with no ladder. The new design is a folded Newtonian that has gained favor in amateur circles as promoted by Mel Bartels from the Oregon family of telescope makers. The telescope design now comes with a flat secondary, instead of the original convex hyperboloid, and the focal ratio will be F/3.6. With such a short focal length, the secondary mirror is quite large - sixteen inches in diam-eter. It is tilted at about 15 to 20 degrees from the optical axis to bring the light path outside of the tube assembly to a diagonal and eyepiece holder at about five feet off the observatory floor when the telescope is pointed towards the zenith.

A short focal ratio like this means that the viewer would normally see an aberration called “coma” that is present with a parabolic reflector, even when

(MILESTONE from Page 3)

it is perfect. Off axis images (stars at the edge of the field) would look like little comets, hence the name of the aberration. A company called Paracorr has come up with a standard coma-corrector lens assembly for just this kind of optical arrangement, and Starlight Instruments has paired it with one of their FeatherTouch focusers so that a visual observer will first rough focus the center of the field, and then use the fine focus adjustment to eliminate any coma for the edge star images. All of this will be on the back of a 3-inch diagonal mirror, the third mirror in this folded design, that will make

(turn to MILESTONE on Page 7)

Page 6 Sp r ing 2015

A Larger Earth, a Smaller SunBy Loren Stokes

We like to think that our Earth and Sun provide a near-ideal place for life to flourish. After all, life has been on Earth for over 3 billion years. However, the best days on Earth may be behind us. I am not talking of any human-caused climate change. Rather, given the nature of our Earth and Sun, it is doubtful there will be life here a billion years in the future. This puts a limit, albeit a large one, on how far life can evolve on Earth. After all, it took 4.5 billion years to get to where we are today. That makes another billion years (or less) seem like not so much time.

Let’s look at Earth’s shortcomings. Earth’s molten iron core is cooling, and as it does several bad things will happen. In the far future, the molten core will solidify, leaving our planet without a magnetic field. Our atmosphere will be damaged by the Sun’s solar wind. Energetic charged particles from solar flares will reign down on Earth’s surface. However, long before this happens, in around a billion years Earth’s internal heat will drop to the point where plate tectonics will stop. All the surface plates will lock together. This has two dramatic consequences.

First, the Earth’s natural cycling of carbon dioxide from the atmosphere, to rock, and back to the atmosphere will stop. Today, our atmospheric carbon dioxide warms Earth’s surface enough for liquid water to be present. Over time, carbon dioxide and rainwater react with rock to form carbonates. Eventually, these rocks are subducted under a plate, heat up, and release their carbon dioxide back to the atmosphere from volcanoes. We would eventually lose most of our atmospheric carbon dioxide if it were not for volcanoes replenishing it. Of course, volcanic eruptions are not constant over time. Over the history of the Earth, the atmospheric carbon dioxide concentration has varied widely, from much less than today (snowball Earth) to many times that of today (tropical polar regions with no ice sheets).

Second, no plate tectonics mean an end to new mountain building. Over time, all the mountains and high plateaus will erode from rain and wind. Given enough time, there will be little land mass left. We will truly have a water planet.

Let’s look at the Sun’s shortcomings. It is about halfway through its 10 billion year lifetime. But long before it becomes a red giant, the Sun will become too hot for life on Earth. A star the size of the Sun increases its energy output by 10% every billion years as it consumes the limited amount of hydrogen in its core. In less than a billion years, Earth’s oceans will evaporate. The water vapor in the upper atmosphere will be broken up by the Sun’s ultraviolet light. We will become a desert planet like Mars.

The timing is unclear – whether Earth becomes a water planet or a frozen planet before a desert planet.

Now consider a super-Earth, one with twice Earth’s mass and arranged similar to our Earth with a molten iron core, solid hot mantle and crust with oceans. The diameter of this super-Earth would be 25% greater than Earth. The surface area would be 56% (1.25-squared) greater than that of Earth. The mass (1.25-cubed) would be twice that of Earth. But because the surface is 1.25 times further from the planet’s center, gravity’s inverse square law (1.25-squared) means our weight would be only 25% greater than that on Earth. Mountains would not be as high as on Earth, animals would be shorter and stockier, but life might not be very different on a super-Earth. With a larger molten core, the super-Earth would sustain a magnetic field and plate tectonics for perhaps several billion years longer than Earth can.

Next, consider this super-Earth orbiting a red dwarf star smaller and cooler than our Sun. Such a star has a near-constant energy output for tens of billions of years. The super-Earth would have to orbit the red dwarf much closer than we orbit our Sun for liquid water to be on its surface. Yet as the red dwarf’s mass is much less than our Sun’s, the orbital period may not be much different than our year. Throw in an axial tilt and the super-Earth would have seasons. This super-Earth, red dwarf system could support life much longer than our Earth-Sun system, perhaps billions of years longer. Perhaps life could evolve wildly beyond our imagination.

Exoplanet hunters are looking for such super-Earth, red dwarf systems. It is actually easier to find these than a system more like our own. Using the radial velocity detection method, the super-Earth would cause the small red dwarf to wobble much more than our Earth-Sun system. Using the transit detection method, a super-Earth transiting a red dwarf would block a larger fraction of the starlight than Earth transiting the Sun. Super-Earth, red dwarf systems should be good candidates to detect life, especially intelligent life.Reference: “Better Than Earth”, Rene Heller, Scientific American, January 2015.

that I don’t have to do everything for a public star party by myself. Putting together one of these weekend star parties at my cousin’s is a fair amount of work. Putting on a public star party, as well as hosting private events, Night Sky classes, and Observing Labs, is also a fair amount of work. Having been a part of the RFO family for 13 years now, I think it is safe to say that the volunteers that make it all happen week after week, month after month, for year after year share the same basic feelings I have when I’m driving home from my cousin’s on Sunday: “Man I’m glad I took Monday off to recuperate.” Or probably more to the point: “That was a great time. I can’t wait to do it again.”

(PRESIDENT from Page 2)

Spr ing 2015 Page 7

(OH MY! from Page 3)

(CONTENT from Page 1)

(MILESTONE from Page 5)

to use the observatory on my own to do astrophotography and photometry. My most recent and proudest accomplish-ment has been the successful imaging of light curves for 3 exoplanet transits. I have volunteered over 1000 hours at the RFO and have learned a tremendous amount of astronomy. I have gained experience teaching, operating telescopes and learning multiple software systems. I have experienced many frustrations and successes. But most importantly, I have learned that this is a field of inquiry that I love and wish to pursue as my career.

Many people say that they feel most alive when amidst nature, isolated from technology and the modern world. This is only partially true for me. Although the objects I study are the epitome of separation from daily life, I thrive amongst technology and scientific investigation. When I am in the observatory, immersed by LED lights and multiple computers, gazing at the immensity of our universe, I feel like I am part of an endeavor larger than myself, contributing to human understanding of our place in the universe and how it works. And that, to me, is the ultimate experience.

is the first NASA mission to orbit more than one object. The Voyagers visited multiply objects but they were flyby missions. Dawn is the first to be placed in orbit around one object, break out of that orbit and go into orbit around a different object.

The technology that made this possible is the ion drive propulsion system. In terms of terrestrial speeds, if you were to put an ion drive in your car you could accelerate from 0 to 60 mph in about 4 days. I don’t think we will be seeing an ion driven Ferrari any time soon but for cruising around the solar system the ion drive is hard to beat. The ion drive was tested by NASA back in 1998 with the Deep Space 1 mission to visit Comet Borrelly, and it is a classic example of New-ton’s second law in action. The idea is to ionize a xenon gas particle with a positive charge and accelerate it out the back of the drive system by means of a negatively charged plate. So even though the particle is extremely small it gets to be moving very fast. The action of accelerating that particle out the backend of the spacecraft causes an opposite reaction that pushes the spacecraft forward. You can experience what that amount of thrust would feel like for yourself by holding a single sheet of notebook paper in your hand. Now you are probably thinking that is next to nothing and you would be correct. The trick of the ion drive is that it throws xenon ions out by the billions and each of those next to nothing reactions add up to keep the ship moving.

Of course, getting from zero-to-sixty in four days is not going to get you off the surface of the earth. We still need good ol’ chemical burning rocket engines to get into space but once we are out there and don’t have to deal with air friction and so much gravity, ion engines are a much more efficient

means of getting around. The Delta II rocket that launched Dawn burned through tons of fuel in just a few minutes. To reach a successful conclusion, the Dawn mission planners estimated that the engines would need enough fuel to burn for over 2,000 days so it left the launch pad with 937 pounds (425 kilograms) of propellant and I’m guessing that includes a pretty good amount of reserve. The ion drive burns through about 10 ounces (3.25 milligrams) of fuel per 24 hours of burn. Maybe we will see an ion driven Toyota someday.

So why visit Vesta and Ceres in the first place. Because we can. That is a bit of a flippant answer but in some ways it is true. At least in the sense of visiting both with one mission. Radioisotope chronology from meteorites believed to have originated from Vesta suggest that it formed fairly early in the history of the solar system. There is no strong evidence that we hold any meteorites from Ceres (after a close up examina-tion of Ceres we may find that we do) but it is believed that Ceres also formed early on. These two may hold some vital clues to the formation of our solar system. Before Dawn paid it a visit Vesta was not much more than a few modest images taken by Hubble. Now we have beautiful images that show signs of geological processes that suggest Vesta has a core, mantle and crust. In other words, it looks like a little planet that was trying to happen.

So Dawn is the first spacecraft to orbit more than one object and the first to orbit a dwarf planet and we will no doubt learn some interesting things. Of course, if you’ve been following the approach to Ceres you know about the bright spots. As Dawn approached Ceres it discovered two very bright spots in an impact basin. Many theories are being tossed around as to what they are but Dawn has not been close enough to get high enough resolution images to draw any conclusions. Currently Dawn is on the night side of Ceres and getting ever closer to the surface in its orbit. It will be coming out of darkness in mid-April at which time we will probably discover that these are just a couple of highly reflective craters like Aristarchus on the Moon and not two big bright observatory domes after all. But stay tuned…

it easier for visitors to look through the telescope.Once the mirror is aluminized, it will go through a series

of tests meant to validate that all of the drive electronics and controls are working correctly and will be usable by our vol-unteers once it is installed at RFO. Then the team will work with the VMOA Board to choose a time when the existing 24-inch reflector that was loaned to us by Board Member Bill Russell and which has given such great service to our visitors will be retired. The new telescope will be installed and final testing done before training begins for the docent team and it is officially opened to the public.

This project has gone through many milestones, but it’s fair to say that this milestone of a successful star test has been the MOST anticipated one of all!

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