From the Outreach Chair

Posted on March 4, 2018 by ST Editors

by Gene Allen

The Outreach Team was invited by a teacher at Stuart Country Day School to introduce star gazing to a class of 4th grade girls plus their parents and siblings. The original date was heavily clouded but the rain date of February 27 started out perfectly clear.

Being only two nights before Full Moon denied us most of the constellations and many of our favorite sights, but we started by showing a bit of lunar detail with the terminator not quite at the southeastern edge. The Pleiades were nicely visible even naked eye, but the nice Mizar-Alcor double was not. Orion was faint but we managed to show The Great Nebula in binoculars and resolve four stars of the Trapezium in a 10” Dobsonian.

An Astronomers Without Borders OneSky, a 5” Newtonian in a tabletop Dobsonian mount, saw First Light and represented itself very well as a $200 starter scope, though it needed a stool to be low enough for the girls.

High clouds encroached to end the program early but the originator declared it a great success.

Ted Frimet, John Giles, David Letcher, and myself participated tonight. Outreach events are entered into the website calendar for everyone to see. Any members who would like to join us for any event or join the Outreach Committee, please write to outreach@princetonastronomy.org.

Posted in March 2018, Sidereal Times | Tagged | Leave a comment

February 13, 2018 Meeting Minutes

Posted on March 4, 2018 by ST Editors

by Jim Poinsett, Secretary

Minutes of the February 2018 Meeting of the Amateur Astronomers Association of Princeton

  • The meeting was called to order at 7:30.
  • Director Rex explained the amendment to the constitution that was to be voted upon, adding outreach and observatory chairs to the board of directors.
  • Voting was conducted and the result was 46 yes and 0 no. The amendment passed.
  • A second vote was taken on the expenditure of up to $2000 for a new camera and accessories for the observatory. All members present voted yes.
  • There was discussion on the new camera. Three models were possibilities:
    • Atik Infinity
    • Starlight Xpress Ultrastar
    • Mallincam Star Vision
  • There are reviews on all three on the Cloudynights forum. All three will be good for public nights and member use.
  • Observatory –
    • Work continues on the focusing end of the HB refractor. It is anticipated it will be ready for the public season.
    • The observatory duty calendar will be out soon. (It is out now).
    • The columns that hold the roof when it is rolled back continue to degrade. Whether to repair or replace is the main question. Discussion will be continued at the next meeting and the board meeting.
  • Bill Murray discussed training keyholders on what to see in the sky this spring and what will be good to show the public. A date will be picked soon, probably in April.
  • There are several Planetarium/Observatory combination nights planned. The first two on the 11th and 18 of May and the second set on the 12th and 19th of October.
  • The planetarium is planning a special presentation on November 24th called “Choosing Your first Telescope”. They would like several members to show up and set theirs up in the lobby for people to see and ask questions about.
  • John Church announced that the HB equatorial head has been found. It is being refurbished and will be put back in use.
  • There was an outreach event at the Stuart Country Day School on Feb 27th. Check the calendar on our website for more Outreach opportunities.
  • The meeting was adjourned.
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if a tree falls in the forest

Posted on March 4, 2018 by ST Editors

and you’re on the wrong side of the park…

by Ted Frimet

An additional observers account of AAAP outreach at the Sacred Heart:

Materials brought to site included:

8” Meade SCT (15 year old scope, alt-az in equatorial mount equivalent install – pointed North, acquired from a Long Island outreach, refurbished, manual only mode. 25mm eyepiece with a passable diagonal).

6” Celestron (Newtownian, German equatorial mount, tripod legs collapsed to accommodate the viewers height, 20mm eyepiece)

15 x 70 Celestron binocular (strap intact for safety, I insist that only a parent or teacher is allowed to put the strap on the student.) small spotting scope – to hand to an observer in the event that binocular or mounted telescopes are not student accessible.

All the above are manual, & all were designated for hands on activity by the kids, or parents. I have done 10 or more outreach (literally just outside our observatory) sessions, last year, using some combination of the above.

Bringing that experience, here at Sacred Heart highlights a few iotas:

When the hands-on scope was set up and ready, almost immediately after announcing its availability, a line grew. This was after the public use of the existing telescopes on the field had already been established, and interest may have waxed and waned.

The “lead” 4th grade astronomer, after being briefed on her Meade 8” SCT telescope, set on teaching others, in line, how to operate in turn.

As the 8” SCT was getting its work-out, I brought out the 15 x 70 Celestron binoculars and handed them off to the first parent, that had none.

I later noted that a fellow astronomer was assisting in acquisition of a star using telrad, on the “hands-on” scope. I breathed a sigh of relief, that the telescope was not unattended, while I was completing a setup, a few feet away.

It is at times like this, that learning functionality trumps true location of a star in a field.

We concur that it is acceptable for a fourth grader to learn how to move a fork mounted or equatorial scope, and not be too concerned with the accuracy of her stellar acquisition.

I continue to observe just how those faces light up, each time they find a star in a telrad center ring, and acquire a star in their eyepiece, of their own accord.

I heard the lead teacher, clearly, when she remarked about one or few stars, and Orion’s nebula. And this must have been concurrent with the various targets, preset by club astronomers, at their scopes.

The “ok to touch and move” display works well enough, when the observer is left to learn, at her own pace. Working independently, she now becomes free of any preconceived notion of what astronomy is. As no adult is choosing for her, I find our budding astronomer forming her own, lasting opinion, experientially.

By the time I had set up the 6” Newtonian reflector, the crowd had diminished. However, I had repossessed the binoculars in time to entertain two parents, and their two girls.

The girls were agape with wonder as they viewed the moon, and the parents had a good view, as well. And further had the opportunity to compare the views from a 6” Newtonian versus the “double” 70mm ocular.

I was surprised when one of the parents discussed the merits of the moons terminator line. And how the moon light interfered with stellar viewing.

A brief engagement in conversation revealed to them that I am from Bucks County.
And one Mom let me know that they were from Newtown, Pennsylvania.

Posted in March 2018, Sidereal Times | Tagged | Leave a comment

Hastings Byrne Refractor – Focuser Re-Fitment

Posted on March 4, 2018 by ST Editors

by Tom Swords

On one of the last public evenings in October in 2017, I was at the Observatory with Jen and Dave Skitt to observe some double stars after we had closed. Dave and I noted that the focuser on the Hasting Byrne refractor was loose in the optical tube. Upon tightening the screws as best we could, it was still not stable.

Now, I am a long focal length refractor fan and know for certain that a loose fitting focusing assembly cannot provide the stable optical-mechanical alignment that is necessary to set and hold accurate collimation. Collimation in a refractor is simply defined as coaxial alignment of all optical-mechanical assemblies and having co-planar alignment of the objective lens surfaces to the eyepiece. In essence: centered and square.

I mentioned to Dave that I would like to investigate and see about repairing this assembly. I contacted and met with John Church, the curator of the instrument. He showed me a mechanical drawing of the scope and gave me a detailed oral history and recounted work that had been done to it. With that information and some additional investigation, I developed and then presented my plan at the October AAAP board meeting to seek approval to proceed with a repair. Approval was granted and on Nov 20th I began.

To start, I installed a laser collimator and noted where the optical centerline (laser dot) landed on the objective lens. The dot was where my finger tip is placed in the picture below. Think of that spot as the center of field seen at the eyepiece. It is far from the ideal optical-mechanical center.
We also observed that the collimation was not aligned. There should be a single point of light.

The Work Begins
The first step was to check and square the rear of the optical tube assembly (OTA) where the focuser is mounted. Upon correcting that and re-mounting the focuser, installing the laser collimator indicated that we had brought the mechanical centerline to within .75 inches of center. Quite an improvement however, the focuser was still not mechanically stable and centered in the tube.



At my home shop, I disassembled the focuser, cleaned and lubricated the mechanism and replaced the rubber tension washers. The interior of the focuser tube was repainted in flat black. The patina of the focuser was left as is with the exception of the maker’s marks.


Next up was the most challenging part of this project. Properly fitting the focuser to the optical tube.

First, a bit of history is required. In 2002 the original focuser had mechanically failed and was replaced by the current focuser donated to AAAP from BD Instruments. It is a custom made Crayford style device weighing 12.5 lbs, constructed of brass, steel and aluminum. However, upon initial fitting in 2002, it was found that focus could not be reached. The OTA was shortened by 1 inch to achieve focus.

Also notable was that the original focuser mounted on the outside of the tube (i.e., the tube slipped inside the focuser). However, the shank of the replacement focuser mounts inside the tube, with machine screws drawing the tube tight to the shank.

The Hastings Byrne OTA is tapered along its length; its diameter is greater in front (at the lens cell) to less in back (at the focuser). When shortened, one inch of the original round section of the OTA supporting the focuser was removed. The result was that part of the new focuser shank was no longer securely in contact with the tube walls. That is why the focuser would become “loose” over time. This can be thought of as a round cylinder inserted into a cone that opens wider.

The OTA ID was measured to be .120” bigger than the shank of the focuser. In addition there was a soldered “lap seam” inside the tube. Unlike today’s seamless aluminum telescope tubes, telescopes constructed in the 1870’s were made in sections of steel or brass. The seams were then soldered with lead and the sections riveted together to form longer tubes.

So I set about constructing a “shim” of mild steel that would be fitted on the focuser shank in order to make up for the space in the larger section of the tube. It also would require a gap to accommodate the lap seam inside the tube. It was constructed from 16ga mild steel that was rolled and then ground to a custom fit between the shank and the ID of the OTA. The final thickness of the shim was .055” and that provided a .010” clearance fit to the tube.


The OTA itself had burrs and dents that were removed along with some gentle expanding to remove the taper of the tube and provide a closer fit of the focuser shank.


After many hours of grinding, trial fittings and adjustments, the shim and focuser were installed on Feb 14th for final trials. The original 6-32 sized fasteners were used initially. The hose clamp, shown in the photo, holds the shim in alignment on the shank while the whole piece is being inserted into the tube. The optical train was then laser aligned to be within .250” of center and the OTA was re-collimated using a refractor collimation tool.


The First Trial
On Sunday Feb 18th, Jen, Dave, my wife (Karen) and I went to the observatory for the trial run.
We decided to use double stars for testing. Viewing began with a 17MM eyepiece @136X. We started in Orion and all of us immediately noted how considerably brighter the views were. Despite the variable viewing conditions doubles were split very cleanly.

The Trapezium in M42 was perfect and if viewing conditions were better we might have seen the E & F components. We viewed 4 stars in Sigma Ori.
Meissa @4.5” separation was very sharp and defined.

Still in Orion, Jen steered us to HD 33055, a Mag9 double @ 2.4” separation that was split perfectly.

We went to Cancer and checked Iota Cnc and Tegmine. Beautiful.

Last target was Algeiba in Leo. I decided to test at high power to see if we could observe an “airy ring”. A 8mm eyepiece for 289X was used.

We observed two perfect spheres with first diffraction rings on each! The rings would come and go, break and reform as the atmosphere played above us. The trial was a success!

The following week, the focuser was removed and the shank was drilled and tapped for larger
10-32 button head socket screws that provide increased torque for mechanical stability. It was reinstalled on Feb 26th. The mechanical alignment was adjusted to be within .125” of center. The OTA was then re-collimated. The finder scope and grab handle were re-installed. Although there is still some cosmetic finish work to be completed on the tube, the telescope is ready for service.

On Feb 27th, Jen, Dave and I did some observation along with re-calibration of the T Point table in TheSkyX. This was done so as to correct the pointing of the mount since the optical center of the telescope had moved with the improved optical-mechanical alignment. Although sky conditions were less than ideal, observation showed that collimation was correct.


I feel privileged to have worked on this historic instrument and would like to thank the AAAP board and John Church for allowing me to do so. It’s ready to observe more of the Heavens and better than ever for its 200 year anniversary in 2079!

Posted in March 2018, Sidereal Times | Tagged , | Leave a comment

Ice Cream Has No Bones

Posted on March 4, 2018 by ST Editors

Feynman was here.

by Ted Frimet

A pleasant lecture was had by all, at last Tuesday’s meeting in Princeton. Paul Halpern was informative, and entertaining as he discussed his book on Richard Feynman. And then I stepped into the trap I laid for myself. When Dr. Halpern was discussing Feynman’s thoughts on electrons moving forward, and backward in time, (evidently the math works, so I’ve been told) I asked a neophyte question if this was akin to quantum tunneling, with an electron paying the price of time, as it passes thru no space, at all. Our author was quick to point out that this theory of the realm of quantum theory was akin to the 1920’s time frame. After prodding him gently, as one would stir a Gridnard reaction into place, Paul helped me out by reminding all that the motions of this particular electron (or positron – depending on your time movement) was taking place in the 1950’s. Oh, Richard – we could have used a smoke and joke, here!

Time is relative. Questions and answer time, doubly so. And when the time came for Q&A, I too heard crickets. I bounded and twisted from my chair, knowing how the speaker felt, and at once queried you all – as if you had no question of your own to offer? And begged my way into asking of the good professor, “whatever happened to Ms. Bell?” You know the answer we got. And the floor was opened and I rejoiced in hearing and listening to all of you participate.

Feynman finally moved me. You see, I’ve been reading “New Quantum Universe” by Tony Hey, and Patrick Walters (which leaves out the math). You now have a clue as to where I am studying Quantum Physics (circa 1980). And although I had been taught, previously that Richard Feynman was difficult to learn from, I ushered into my living room, in the comfort of my own home, the YouTube channel that hosted his 1979 lecture from New Zealand. Auckland, I recall? And I learned that Richard is the man! Funny, bright, succinct, and yes, easy to understand. Why, I even drew reference from Feynman’s work. I compared it to a recent review I am working on. I am critiquing the graphic art in a 50 minute video discussing the underpinning of Snell’s Law. But you don’t want to hear of that until I finish the graphical critique. Stay tuned, because I’ll give a shout out to the author, here, in Sidereal Times, when the bun is out of the oven.

I am writing this second essay, because I wanted to relay to you what I’ve learned, recently. That Buddhists teach that once the mountains are mountains. And then you realize they aren’t. And then, they resolve to be mountains, once again. Boy, I really butchered that thought. Feynman helped me re-engage our reality of light. That is, when light “hits” matter, it causes the electron quantum state to either excite, or cascade into a lower level (basically). And in doing so, emits a photon of its own. Sometimes two or more. Depends on your physics. This photon, may in its terminus, reach your eyes.

So my mountain, as I explain it to you, may be lit by suns afar. However I never get to see the reflected light. It is in fact, re-radiated by the electrons of that matter, itself. As Amateur Astronomers, you get this immediately, as we turn our attention to White Dwarfs emitting non-visible Ultra Violet energy, being absorbed by a non-visible veil of a Nebula to be re-radiated by a now – visible Nebula. Ah, essays of old come to roost once again. However, when you look at the paint on the walls, it just doesn’t seem that the wall color isn’t reflected. At least, at first, until you grasp at the electrons doing the physics provide you with the privilege of seeing the wall color. Illusion of light prevails. Things are quite what they seem. And we rely on our brains to fill in the missing pieces, and help us maintain our sanity, less we stop to ponder the true nature of matter and energy.

I laughed out loud when Richard Feynman talked about a physicist that might not accept the light coming from their meal, when presented with a real steak on a plate. Poorly paraphrased here, he mused to the audience that those scientists that would refute the light, would end up being very hungry physicists. I suspect they would be selected out of the gene pool, for sure.

I have to stop now, and eat dinner. And do so before the cat photons eat the chicken tenders.

Posted in March 2018, Sidereal Times | Tagged , | Leave a comment

Poohs’ Hunney Pot

Posted on March 4, 2018 by ST Editors

asteroid velocity reprise

by Ted Frimet

I attended a presentation on asteroid occultation and IOTA, hosted at Montclair State University, by NJAG member Albert Carcich. I found Alberts lecture and slide presentation on measuring asteroid size and shape to be very appealing, and an deceptively easy topic to grasp. A thought quickly developed. Could I use the results of one chord, instead of many, to rough estimate an asteroid diameter? Probably not, I’ve been told. Of course, you would have to be at midline, during measurement and lucky. And lacking the negative reports of the “shadow boundaries” during an an asteroid eclipsing a star, the results would be sketchy at best. In fact, I have been told that it is inherently flawed. I agree. Not knowing my head from my tail, I reached out, once more.

I reached out to IOTA membership, and they were very helpful. I was hopeful that knowing how to calculate an asteroid Vt, that the occultation shadow velocity would prove out a ratio, that might divulge its hidden metrics. Either there were no takers, or my education was so lacking that I failed to materialize the math. Probably the latter. As such, I am vying to move forward. I have attempted purchases on the cheap, used copies of: The “Explanatory Supplement to the Astronomical Almanac” by J. Meeus and “Textbook on Spherical Astronomy” by R.M. Green. And Astronomical Tables of the Sun, Moon, and Planets, by J. Meeus. Regretfully, I am unable to locate a copy of the Supplement to the Astronomical Almanac, at a low enough cost. However the Tables, and Textbook should confound and confuse me for a least a few months to come! UACNJ member, Kris Kootale, will set aside another tome, for me to borrow – Meeus’ Astronomical Algorithms, next time we meet on observers duty for 2018 at Jenny Jump.

I will have a tool at my disposal. It is the Occult program. Since the many supported algorithms are very complex, they do not lend themselves to easily being implemented by hand. Certainly not by me! Using Occult, however, I will have a proven staple to compare any results I obtain, otherwise. I should be downloading and fidgeting with software, before any of my books arrive from the U.K., or elsewhere.

There is NOVAS code, available on the Navy’s MIL website for occultation study. However it has been decades since I’ve used Fortran, and I don’t think it a good idea to reverse engineer any C programs. There is, as good fortune even smiles on us all from time to time – a Github site where the code sits ready for compilation. Here, too, I will take a pass, having decided on taking the longer road to knowledge. I am as foolish in my math pursuits, as I am at the eyepiece of a telescope. Perhaps, during my travels I will write snippets of Visual Basic code in .NET with a fully functioning interface. I own that skill. That might even help the next traveler on their way. The next IOTA meeting, in Suffern – NY, is a full week before NEAF. I plan to attend both.

Last AAAP meeting I reached out to membership, voicing my concerns on the CLEA software model, Astrometry of Asteroids. Member Matthew Rapp’s suggestion was fully grounded when he recommended using the sample files to learn from. Being Mac based, and confusing the install with previous software that was buggy, I had my concerns. I was happy to find out that I didn’t need to create a Virtual Machine to install Astrometry. My current installation of Bootcamp, running Windows 10, was more than sufficient. I did, however find it necessary to move forward with the more advanced Astrometry toolkit, which provided me with access to star catalogues not found in the student version.

And now a pause for errata on last months essay, “How to Haul Tail”. I have since revisited the FITS files. I have taken notice that there are two places for observation times and dates in the FITS file format. Please take note that using either FITS header field results in same outcome of 2,208 elapsed seconds.

For asteroid Griqua image 0: First occurrence of the FITS field for date time group:
DATE-OBS= ‘2017-12-27T01:30:21’ /YYYY-MM-DDThh:mm:ss observation start, UT

Second occurrence of the FITS field for date time group:
DATE = ‘2017-12-27′ / Date at start of exposure, UT
TIME-OBS= ’01:30:06.154’ / Time at start of observation, UT

For asteroid Griqua image 7:
First occurrence of the FITS field for date time group:
DATE-OBS= ‘2017-12-27T02:07:06’ /YYYY-MM-DDThh:mm:ss observation start, UT

Second occurrence of the FITS field for date time group:
DATE = ‘2017-12-27′ / Date at start of exposure, UT
TIME-OBS= ’02:06:53.926’ / Time at start of observation, UT

Onwards! I wanted to refine my hunt for asteroids, by learning how to extrapolate their locations in an astrophotography image. Using the Skynet image frame center as the target “home” position was sufficient. The Skynet observers user interface easily communicated that information to me. I have noticed some drift, as the asteroid falls out of the field of view, during some endeavors. I decided that if I was going to continue to calculate and refine asteroid metrics, I was in need of a more precise measurement method. Using the Astrometry program, I can now select navigational, also known as, reference stars. The program effortlessly interpolates the asteroid location, in RA and DEC. It appears to be highly precise, and a decent tool for this student of Amateur Astronomy.

The same can be accomplished in Afterglow software, provided for in the Skynet interface. This post processing tool provides a window into the associated Digital Sloan Survey (DSS) images. You can select any point, on a corresponding frame and read off the correct RA/DEC coordinate. However, there is presently no way to overlay the asteroid image onto a DSS, as they are in two different non-corresponding proportions. You could “point and guess”, however I wanted something a bit more precise. Enter Toolkit for Astrometry.

There are a couple of user interface “traps” in the Astrometry tool kit, however none of them are fatal. For instance, the interface may ask you to load a CD – as I have neither the CD and my Mac Book Pro doesn’t sport a CD ROM interface. I successfully click “no”, and flawlessly move on with the program. A sensitive area to some, however to me was just a passing inconvenience, is that some message boxes will populate with invisible content. I found a quick solution by employing two monitors. After moving the message box to the second, auxiliary monitor, the box properly populated, and I was able to click away my response. I subscribe the error not to the program, but to how it interfaces with my systems graphics card, and subsequent operating system. The interface issue lay with a “screen refresh” routine. Otherwise, please know that the program is intuitive, and easy to use.

Just like my first night out at Jenny Jump, versus skies that were not as dark, it is easy to get lost among the stars. My astrophotography of 1362 Griqua, being limited to 4 second exposures, would only express the brightest objects in frame. And using Astrometry, I would be bombarded by stars of 20th magnitude or more. What to do? Skynet to the rescue! Using the astrometric tools afforded by Afterglow, I selected the navigational stars that would help me in my asteroid hunt.

Deploying Astrometry. Shown below are the reference star results for magnitude = 22 or brighter. This is followed by the magnitude data for Griqua FITS 000, and FITS 007 at 4 seconds exposure. Note that Afterglow photometry, by itself, does not provide RA and DEC.




I then applied a magnitude limit of 16 to the Astrometry initialization file. And proceeded to select three or more reference stars. Below is the result for Griqua FITS 000, followed by FITS 007. Immediately below the reference star images you will find JPEGs from Skynet for comparison.




The Griqua asteroid, in both Skynet images appears to hold steadfast in center of frame.
This becomes an ideal test to recalculate and refine tangential velocity, using Astrometry coordinates.

Here are the Astrometry coordinates as reported for:
    Griqua (0) =
    RA = 0h 27m 52.99s Dec = -24° 59′ 22.5”

    Original Griqua (0) observers data from Skynet:
    RA/Dec: 00:27:52.198 | -24:59:39.468

    and Astrometry, this time, for Griqua (7) =
    RA = 0h 27m 55.43s Dec = -24° 58′ 51.8”

    Original Griqua (7) observers data from Skynet:
    RA/Dec: 00:27:54.559 | -24:59:11.705

Below is the sample astrometric solution for Griqua (0).

    2018/02/17 4:26:17 PM
    Image 1 – Astrometric Solution

    Image File Name: GRIQUA_2335994_LUM_000S.FIT
    Object: Griqua 1362
    Observation Date: 2017 December 27, UT: 01:30:21
    

Target Object:
    x = 515.4494, RA = 0h 27m 52.99s
    y = 510.9753, Dec = -24° 59′ 22.5″
    m = 15.07 (No Filter)

Estimated errors cannot be calculated!
    N(=3) is minimum for selected solution type.
Estimated Error in Magnitude (Sigma): 0.03(3)

    Field Center:
    x = 512.0000, RA = 0h 27m 53.13s
    y = 512.0000, Dec = -24° 59′ 23.1″

    Plate Constants for Linear Solution:
    Scale = 0.5865 “/pixel, Field Wd. = 10.01′, Ht. = 10.01′ Notes:

    (X = a*x + b*y + c)
    a = 2.8460361E-06, b = -6.0589289E-09, c = -1.5222572E-03

    (Y = d*x + e*y + f)
    d = -9.6308291E-09, e = -2.8407851E-06, f = 1.5439454E-03

(1) Star not used in astrometric solution.
(2) Star not used in magnitude solution.
(3) Magnitudes are unreliable due to errors in reference star magnitudes and passband differences.

Using last months essay, “How to Haul Tail”, I have followed the same procedure to calculate the tangential velocity of asteroid 1362 Griqua. However, this month, we substitute the Astrometric’s solution for the asteroid coordinates:

    Griqua observation 0 – DEC
    24 degrees 59 minutes 22.5 arc seconds
    (24 x 3600) + (59 x 60) + 22.5 = 89962.5

    Griqua observation 7 – DEC
    24 degrees 58 minutes 51.8 arc seconds
    (24 x 3600) + (58 x 60) + 51.8 = 89931.8

    Griqua observation 0 – RA
    0 hours 27 minutes 52.99 seconds
    (0 x 3600) + (27 x 60) + 52.99 = 1672.99

    Griqua observation 7 – RA
    0 hours 27 minutes 55.43 seconds
    (0 x 3600) + (27 x 60) + 55.43 = 1675.43

    DEC difference = 30.7 arc seconds
    RA difference = 2.44 seconds

I am keeping the time difference, from the already published essay, which was 2207.772.

I found an additional math error that I overlooked in the FITS file format, today. Without passing judgment on the essay precision – I calculated for both, and found a 3 second difference.

After “rounding” the angular velocity the answer ended up the same, as 0.021
    2.44 x 15 x cosine (-25) = 33.171
    sq root of ( ( 33.171 * 33.171) + ( 30.7 * 30.7 ) )
    sq root of (1100.32 + 942.99)
    sq root of (2042.81)
    =45.198

    45.198 / 2207.772 = 0.021 (angular velocity)
    Tangential Velocity = (Angular Velocity x Distance) / 206265
    Vt = (0.021 x 287306800) / 206265
    Vt = (6033442.8) / 206265
    = 29.25 km/s

I have calculated that using Astrometry reference stars, and interpolated coordinates, 1362 Griqua, is moving at a higher measured velocity of 29.25 km/s versus last months calculation (using Skynet data) at 26.5 km/s.

Using an online calculator, we arrive at a solution that results in a 10 percent difference. I am inclined to believe that this is a sufficient precision shift. I will be dipping my hand in the Astrometric’s hunney pot, from time to time, now. Which will make future amateur asteroids analysis a sweeter preoccupation.

Posted in March 2018, Sidereal Times | Tagged , | Leave a comment

Falcon Heavy

Posted on March 4, 2018 by ST Editors

by Prasad Ganti

SpaceX added another feather to its cap by launching the Falcon Heavy rocket with a much heavier payload than any other rocket before. Its maiden flight has garnered success. This flight makes it the heaviest launcher in the market and makes Elon Musk of SpaceX a highly accomplished entrepreneur. In addition to building electric cars and solar panels, he is building rockets and also launching satellites to provide internet connections all over the world. He gains my utmost respect.

Much has been written about the launch. Just thought of adding my two cents. Two factors about this launch capture my imagination. Firstly, the price of the launch is very cheap, about a quarter of the next most powerful rocket, the Delta IV Heavy, which is produced by joint venture between Lockheed Martin and Boeing. And Falcon Heavy can launch twice the payload as Delta IV.

Secondly, SpaceX has componentized their launchers. Falcon Heavy uses the same booster as the Falcon 9. It has 3 of the Falcon 9 boosters strapped together. Each booster with 9 Merlin engines. The engines and the Falcon 9 booster become like Lego blocks which can be used to put together different structures in future. The Big F rocket which is part of Musk’s dream of colonizing Mars will use the same Lego blocks to build a bigger structure. No prizes for guessing what the F means!

A major reason for the cheap cost of launches is SpaceX’s ability to reuse the first stage boosters. In fact, 2 of the 3 boosters on this launch, flew previously. And 2 of the 3 boosters from the current launch came back a few minutes after the launch and landed softly in the proximity of the launch pad to be refurbished and reused for future launches. The rocket’s central booster was supposed to come back and land on a ship out at the sea but there was some hiccup in this landing. The second stage of the Falcon containing Musk’s Telsa car was shot into the space. It is circling the Sun between Earth and Mars. Likely to be there for the next few million years or so. Regardless, it was a major success for SpaceX.

Another major factor is that SpaceX has mostly used commercially available off the self-components to reduce costs. Rather than getting them custom built. There is an old story where NASA is reported to have spent a million dollars getting a ball point pen to work in space. Russians had a simpler solution. They used a pencil instead! SpaceX has lot of such cost saving ideas built in.

Of late, private space ventures have proved to be efficient-validating NASA’s mantra of faster, cheaper, and better. NASA itself is working on its Space Launch System (SLS) for a heavy launcher. SLS is using RS-25 engines developed in the space shuttle years. Granted they are updated with more thrust. It is designed to preserve existing space-industry jobs as much as it is to fly cargo into the orbit. Its maiden voyage is not expected until 2020. Do we really need NASA to be in the business of building launchers ? I don’t think so.

Should we depend only on SpaceX ? No, but there are other companies which are coming up to speed. Blue Origin from Amazon’s Jeff Bezos is an example. Orbital Sciences’ Antares rocket is another example. There are other countries doing the launches for lower costs. India’s PSLV (Polar Satellite Launch Vehicle) and GSLV (Geo Stationery Launch Vehicle) launchers cost less and are scaling up in terms of the weight of the payload.

Regardless, NASA is not the only game in the town. In fact, it is no longer the stronger competitor it once was. It should do what it does best. Doing Research and Development. Developing future road maps. And planning space missions. And let the nuts and bolts be done by the better suited private companies.

Posted in March 2018, Sidereal Times | Tagged , | Leave a comment

Snippets

Posted on March 4, 2018 by ST Editors

compiled by Arlene & David Kaplan

Artwork credit: ESA

Artwork credit: ESA

Design call for ‘solar sentinel’ mission
UK scientists and engineers will play a leading role in developing a satellite that can warn if Earth is about to be hit by damaging solar storms.
The European Space Agency has requested studies be undertaken to design the mission that would launch in the 2020s…more

Artwork credit: NASA

Artwork credit: NASA

‘Serious gap’ in cosmic expansion rate hints at new physics
A mathematical discrepancy in the expansion rate of the Universe is now “pretty serious”, and could point the way to a major discovery in physics, says a Nobel laureate. The most recent results suggest the inconsistency is not going away. Prof Adam Riess told BBC News that ..more

Dust entering our atmosphere -BBC

Dust entering our atmosphere -BBC

Is dust the source of life on Earth?
Philip Pullman fans will be familiar with the fictionalised idea of dust. But a new University of Edinburgh study suggests it might really be the source of life on earth.
Fast flowing streams of interplanetary dust are continually entering our planet’s atmosphere, travelling at up to 70 km per second…more

Hubble watched the neutron star merger light fade away = BBC

Hubble watched the neutron star merger light fade away -BBC

Gravitational waves: So many new toys to unwrap
Whenever there’s a big science discovery, it’s always nice to get a historical perspective. And so here goes with the remarkable observation of gravitational waves emanating from the merger of two dead stars, or neutron stars, some 130 million light-years from Earth…more

Artwork credit:BBC

Artwork credit:BBC

‘Oumuamua: ‘space cigar’s’ tumble hints at violent past
The space interloper ‘Oumuamua is spinning chaotically and will carry on doing so for more than a billion years.
“At some point or another it’s been in a collision,” says Dr. Wes Fraser from Queen’s University…more

Credit: Getty Images

Credit: Getty Images

Crypto-currency craze ‘hinders search for alien life’
Scientists listening out for broadcasts by extra-terrestrials are struggling to get the computer hardware they need, thanks to the crypto-currency mining craze, a radio-astronomer has said…more

Galaxy NGC 613 -NYT

Galaxy NGC 613 -NYT

He Took a Picture of a Supernova While Setting Up His New Camera
On Sept. 20, 2016, Victor Buso, an amateur astronomer in Rosario, Argentina, was checking out the new camera on his telescope by taking pictures of a nearby spiral galaxy when a star within it went off in a supernova explosion…more

Superionic water: solid or liquid? -NYT

Superionic water: solid or liquid? -NYT

New Form of Water, Both Liquid and Solid, Is ‘Really Strange’
Long theorized to be found in the mantles of Uranus and Neptune, the confirmation of the existence of superionic ice could lead to the development of new materials…more

Posted in March 2018, Sidereal Times | Tagged , | Leave a comment

From the Director

Posted on February 2, 2018 by ST Editors

Rex

 

 

 

by Rex Parker, Director

Two proposals for vote at Feb 13 meeting. Last year we didn’t hold the Feb meeting because it would be on Valentine’s Day! This time around you have no such excuse (!) so we hope to see you at Peyton Hall on Feb 13. You are needed to vote on 2 proposals: (1) Amendment to the Constitution and By-Laws; (2) Expenditure authorization for a new astro video camera.

Amendment to Constitution and By-Laws. The amendment proposal is aimed at improving the organizational structure of AAAP by raising Observatory Chair and Outreach Coordinator to Board-level positions. We believe the prestige and recognition of the roles and the effectiveness of the positions would be enhanced by making them Board-level positions. They would be elected by the membership each year as are the other officers (Director, Assistant Director, Treasurer, Secretary, and Program Chair), comprising a 7 member Board of Trustees. Further rationale for this amendment is discussed in last month’s Sidereal times. The relevant sections are Constitution article 3, and By-Laws section 1. The current version is at this link, http://www.princetonastronomy.org/club_by_laws.html.

The proposed amendment also makes an additional change in the By-laws, Section 6.D.a (Finance). This would increase automatic expenditure authorization up to $500 (formerly $200) for astronomy equipment or observatory improvements at the discretion of the Officers. This is based on practicality for operating the Observatory.

Adoption of the Amendment requires a majority vote of the total membership, as provided in Article V of the Constitution.

Expenditure authorization: $2000 for astro video camera. This proposal is aimed at upgrading equipment and technology to improve observing capability for members and public outreach at the Observatory and in the field. The proposal is for $2000 from the treasury to be used to acquire a color CCD video camera and accessories for electronic assisted astronomy (EAA). To defray the cost, last month we sold some older unused astronomy equipment on Astromart, adding over $2000 to the treasury.

This Expenditure proposal must be approved by a majority of the votes cast at the meeting and not less than 30% of the paid membership, as provided in By-Laws section 6.D.c.

The club began its exploration of EAA a few years ago with the Mallincam video setup at the Observatory – with great success. More recently, EAA sessions by members at Starquest in October and at the Observatory in December demonstrated the improved sensitivity and very fast download rates of the latest generation of astro video cameras. Several models are eyepiece sized with low power requirements allowing field use with only a laptop-PC for power supply. Software has been developed allowing near-real-time color display of images on the laptop. Examples include cameras using the Sony EXview HAD CCD sensors such as the Sony ICX825. A short list of recommended cameras will be discussed at the Feb meeting.

Posted in February 2018, Sidereal Times | Tagged , | Leave a comment

From the Program Chair

Posted on February 2, 2018 by ST Editors

By Ira Polans

The February meeting will be held on the 13th at 7:30PM in Peyton Hall on the Princeton University campus.

The talk is by Paul Halpern on his book “The Quantum Labyrinth: How Richard Feynman and John Wheeler Revolutionized Time and Reality”.

From black holes and wormholes to gravitational waves and the participatory universe, this talk will show how the work of American physicists Richard Feynman and John Wheeler, who first worked together at Princeton in the early 1940s and had strikingly distinct personalities, had a major impact on contemporary science.

During the break there will be a book signing.

Prior to the meeting there will be a meet-the-speaker dinner at 6PM at Winberie’s in Palmer Square in Princeton. If you’re interested in attending please contact program@princetonastronomy.org no later than Noon on February 13.

We are still looking for volunteers to give a 10 minute talk on an astronomy related topic at a future meeting. If you’re interested in giving one in February or at a later meeting please contact me at program@princetonastronomy.org.

If you have suggestions for speakers please send them to the same email address. Please provide the speaker’s name, topic, and affiliation. Thanks!

We look forward to seeing you at the February meeting and the dinner!

Posted in February 2018, Sidereal Times | Tagged , , | Leave a comment