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Messages posted by: wildcard
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Hi Dave,

Thanks for the post.

Sorry to hear things have become more of a physical challenge for you, but great to hear you are determined to solider on.

To help me appreciate the scenario, I gather you can't get up to the eyepiece any more and will be doing imaging through the same camera as well?

Does the scope happen to be permanently set up in an observatory?

I can then put the thinking cap on and see if we can suggest a solution, including possibly feeding back the az/alt to find the alignment stars.

A 16th April 2020 press release by the European Southern observatory (ESO) reports :-

ESO wrote:
Observations made with ESO’s Very Large Telescope (VLT) have revealed for the first time that a star orbiting the supermassive black hole at the centre of the Milky Way moves just as predicted by Einstein’s general theory of relativity. Its orbit is shaped like a rosette and not like an ellipse as predicted by Newton's theory of gravity. This long-sought-after result was made possible by increasingly precise measurements over nearly 30 years, which have enabled scientists to unlock the mysteries of the behemoth lurking at the heart of our galaxy.

“Einstein’s General Relativity predicts that bound orbits of one object around another are not closed, as in Newtonian Gravity, but precess forwards in the plane of motion. This famous effect — first seen in the orbit of the planet Mercury around the Sun — was the first evidence in favour of General Relativity. One hundred years later we have now detected the same effect in the motion of a star orbiting the compact radio source Sagittarius A* at the centre of the Milky Way. This observational breakthrough strengthens the evidence that Sagittarius A* must be a supermassive black hole of 4 million times the mass of the Sun,” says Reinhard Genzel, Director at the Max Planck Institute for Extraterrestrial Physics (MPE) in Garching, Germany and the architect of the 30-year-long programme that led to this result.

Located 26 000 light-years from the Sun, Sagittarius A* and the dense cluster of stars around it provide a unique laboratory for testing physics in an otherwise unexplored and extreme regime of gravity. One of these stars, S2, sweeps in towards the supermassive black hole to a closest distance less than 20 billion kilometres (one hundred and twenty times the distance between the Sun and Earth), making it one of the closest stars ever found in orbit around the massive giant. At its closest approach to the black hole, S2 is hurtling through space at almost three percent of the speed of light, completing an orbit once every 16 years. “After following the star in its orbit for over two and a half decades, our exquisite measurements robustly detect S2’s Schwarzschild precession in its path around Sagittarius A*,” says Stefan Gillessen of the MPE, who led the analysis of the measurements published today in the journal Astronomy & Astrophysics.

Most stars and planets have a non-circular orbit and therefore move closer to and further away from the object they are rotating around. S2’s orbit precesses, meaning that the location of its closest point to the supermassive black hole changes with each turn, such that the next orbit is rotated with regard to the previous one, creating a rosette shape. General Relativity provides a precise prediction of how much its orbit changes and the latest measurements from this research exactly match the theory. This effect, known as Schwarzschild precession, had never before been measured for a star around a supermassive black hole.

The study with ESO’s VLT also helps scientists learn more about the vicinity of the supermassive black hole at the centre of our galaxy. “Because the S2 measurements follow General Relativity so well, we can set stringent limits on how much invisible material, such as distributed dark matter or possible smaller black holes, is present around Sagittarius A*. This is of great interest for understanding the formation and evolution of supermassive black holes,” say Guy Perrin and Karine Perraut, the French lead scientists of the project.

This result is the culmination of 27 years of observations of the S2 star using, for the best part of this time, a fleet of instruments at ESO’s VLT, located in the Atacama Desert in Chile. The number of data points marking the star’s position and velocity attests to the thoroughness and accuracy of the new research: the team made over 330 measurements in total, using the GRAVITY, SINFONI and NACO instruments. Because S2 takes years to orbit the supermassive black hole, it was crucial to follow the star for close to three decades, to unravel the intricacies of its orbital movement.

The research was conducted by an international team led by Frank Eisenhauer of the MPE with collaborators from France, Portugal, Germany and ESO. The team make up the GRAVITY collaboration, named after the instrument they developed for the VLT Interferometer, which combines the light of all four 8-metre VLT telescopes into a super-telescope (with a resolution equivalent to that of a telescope 130 metres in diameter). The same team reported in 2018 another effect predicted by General Relativity: they saw the light received from S2 being stretched to longer wavelengths as the star passed close to Sagittarius A*. “Our previous result has shown that the light emitted from the star experiences General Relativity. Now we have shown that the star itself senses the effects of General Relativity,” says Paulo Garcia, a researcher at Portugal’s Centre for Astrophysics and Gravitation and one of the lead scientists of the GRAVITY project.

With ESO’s upcoming Extremely Large Telescope, the team believes that they would be able to see much fainter stars orbiting even closer to the supermassive black hole. “If we are lucky, we might capture stars close enough that they actually feel the rotation, the spin, of the black hole,” says Andreas Eckart from Cologne University, another of the lead scientists of the project. This would mean astronomers would be able to measure the two quantities, spin and mass, that characterise Sagittarius A* and define space and time around it. “That would be again a completely different level of testing relativity," says Eckart.

Press release including artist impression here :-

JohntheLast wrote:That was the conclusion that I was coming too. Obvious, once you think about it. I didn't see any reference in the manual (but I may have missed it). If it's not there, perhaps a point should be made (even if obvious) that if you are using a Servocat you may have to disconnect the Serial 1 cable that goes to the Servocat and temporarily replace it with a direct connection to the PC.

BTW, you'll find an order in your stack for the serial cable.

Thanks again for the quick response and help. Your product has made the difference between being able to observe and just sit on the sidelines. I live in a very light polluted area and the ability to GOTO and Tour with the capability that you provide makes the difference between being a participant and being a by stander.

Your Argo Navis Serial Cable shipped by Economy Airmail earlier today.

Good to see you probably tumbled as to the requirement for a direct connection between the Argo Navis and PC when I mentioned
you explicitly need to use the Argo Navis Serial Cable which is different to the ServoCAT Cable.

You may not have been the first to try it via the ServoCAT but you are definitely the first I am aware of from a support perspective,
so it has provided me with another question to ask people and the prompt to add an additional line of text to the User Manual. smilie

Hopefully once your Serial Cable it will all go smoothly.

Thank you for the additional anecdote on how using your Argo Navis is a gamechanger under light-polluted skies. That's really wonderful to hear.

Clear skies!

JohntheLast wrote:This may be a stupid question but in the Servocat configuration the Serial 1 port on the argonavis is connected to the DSC port on the Servocat. The Servocat USB port is then connected to the USB port on the PC. That would tell me that there is no direct connection between the argonavis and the PC (although there may be an internal pass through on the Servocat).

For the upgrade process, does the argonavis Serial 1 port have to be directly connected to the PC (i.e. not go through the Servocat)?

There is never a stupid question here smilie

When you have that daisy chain of PC <-> ServoCAT <-> Argo Navis, there is no direct connection between the PC and the Argo Navis.
What happens is that the ServoCAT relays requests and responses onto and back from the Argo Navis. So for example, Argo Navis is
responsible for performing all the object offset and tracking rate calculations on behalf of the ServoCAT and that dialog takes place
just between the two of them. Now and then the PC might request where we are at in terms of RA/Dec coordinates and the ServoCAT
relays that request onto the Argo Navis and it then relays the response back to the PC.

For the upgrade process, the Argo Navis must be directly interfaced to the PC.

If the ServoCAT were to see the Argo Navis firmware data, it would not be able to make head or tail of it.

Hence you must use the Argo Navis to PC Serial Cable in conjunction with the USB Serial Adapter. The Argo Navis to ServoCAT cable is wired
completely differently.
JohntheLast wrote:Am I also interpreting the baud rates correctly.

The Baud rate for the Serial 1 to DSC interface on the Servocat should be 19200 and the USB/COM4 interface should be 38400?

When you power up the unit in normal mode, the serial port protocols and Baud rates are determined by whatever they are set to in the SETUP SERIIAL menu.

For interfacing to a ServoCAT the setting is BAUD=19200 STARTUP=servocat

If you wanted to run the check for the % prompt as detailed in the Establishing Communication section of the User Manual,
set the port being interfaced to the PC with a BAUD=38400 and STARTUP=navis.

Whenever you change the STARTUP command, press ENTER or EXIT to make the change and then power the unit OFF and ON to make the new STARTUP protocol to start.

When in BOOT LOADER mode, the settings in SETUP SERIAL are no longer applicable. The only serial port that is then operationally valid is SERIAL1.
It's Baud rate is fixed at 38400. This therefore is the Baud rate at which firmware upgrades take place.

Argonaut works with all versions of Windows including Windows 10.

The USB Serial Adapter we recommend is the Keyspan USA-19HS.

Some have success with adapters using the FTDI chipset but the correct driver is crucial.
Brand of USB Serial Adapter?

Had you successfully communicated with your Argo Navis using it before, or is this the first time you have used this combination?

Get some sleep and we are here to assist when the time comes. smilie
Are you using a USB and if so, what brand?

If you open the Device Manager and expand the Ports (COM & LPT) section, what COM port number has been assigned to that device?
Is it COM4? If you can make a screenshot, showing the ports that are enunciated in the Device Manager, it would be helpful.

Ignore cursors, blinking or otherwise.
Thanks for the post.

The Argo Navis User Manual is available here :-

It has a wonderfully written section starting on page 168 under the sub-heading "Establishing communication".
If you have not done so already, I recommend you work through it step by step, including examining the Windows
Device Manager to determine which COM port Windows actually assigned to your serial port or USB Serial adapter.
It also details, including with screenshots, of how to change the COM port assignment to be in the range 1 through 4 if need be.

It is important to keep in mind that just because Argonaut might allow you to connect to a COM port without complaint. it does not
necessarily mean that COM port exists. Likewise, if you see a flashing block cursor in the Argonaut terminal window area, it does not denote
a successful connection.

It is also important to ensure that you are using the proper Argo Navis to PC Serial Cable. Others might look like it, but can be wired
completely differently and therefore will not work.

I noted a similar question appeared on the Cloudy Nights forum today. Due to some of the fine print terms and conditions there, we
choose not to participate on that forum.

The best possible advice can either be provided by contacting us by email or phone directly or by asking a question here.

Do quantum chromodynamics (QCD) axions, first theorized in 1977, exist?

While the QCD axion has never been directly detected, theoreticians
behind a new study propose that it provides added fuel for
experimentalists to hunt down the elusive QCD particle.

They claim that if QCD exist, it would go a long way to explain many things
about the universe.

In a 10th March 2020 press release from the Institute of Advanced Studies
(IAS) in Princeton :-

Press Contact, Lee Sandberg, IAS wrote:
A new study, conducted to better understand the origin of the universe, has provided insight into some of the most enduring questions in fundamental physics: How can the Standard Model of particle physics be extended to explain the cosmological excess of matter over antimatter? What is dark matter? And what is the theoretical origin of an unexpected but observed symmetry in the force that binds protons and neutrons together?

In the paper “Axiogenesis,” scheduled to be published in Physical Review Letters on March 17, 2020, researchers Keisuke Harigaya, Member in the School of Natural Sciences at the Institute for Advanced Study, and Raymond T. Co of the University of Michigan, have presented a compelling case in which the quantum chromodynamics (QCD) axion, first theorized in 1977, provides several important answers to these questions.

“We revealed that the rotation of the QCD axion can account for the excess of matter found in the universe,” stated Harigaya. “We named this mechanism axiogenesis.”

Infinitesimally light, the QCD axion—at least one billion times lighter than a proton—is nearly ghost-like. Millions of these particles pass through ordinary matter every second without notice. However, the subatomic level interaction of the QCD axion can still leave detectable signals in experiments with unprecedented sensitivities. While the QCD axion has never been directly detected, this study provides added fuel for experimentalists to hunt down the elusive particle.

“The versatility of the QCD axion in solving the mysteries of fundamental physics is truly amazing,” stated Co. “We are thrilled about the unexplored theoretical possibilities that this new aspect of the QCD axion can bring. More importantly, experiments may soon tell us whether the mysteries of nature truly hint towards the QCD axion.”

Harigaya and Co have reasoned that the QCD axion is capable of filling three missing pieces of the physics jigsaw puzzle simultaneously. First, the QCD axion was originally proposed to explain the so-called strong CP problem—why the strong force, which binds protons and neutrons together, unexpectedly preserves a symmetry called the Charge Parity (CP) symmetry. The CP symmetry is inferred from the observation that a neutron does not react with an electric field despite its charged constituents. Second, the QCD axion was found to be a good candidate for dark matter, offering what could be a major breakthrough in understanding the composition of approximately 80 percent of the universe’s mass that has never been directly observed. In their work on the early universe, Harigaya and Co have determined that the QCD axion can also explain the matter-antimatter asymmetry problem.

As matter and antimatter particles interact, they are mutually annihilated. In the first fraction of a second following the Big Bang, matter and antimatter existed in equal amounts. This symmetry prevented the predominance of one type of matter over the other. Today, the universe is filled with matter, indicating that this symmetry must have been broken. Harigaya and Co cite the QCD axion as the culprit. Kinetic energy, resulting from the motion of the QCD axion, produced additional baryons or ordinary matter. This slight tipping of the scale in favor of matter would have had a pronounced cascade effect, paving the way for the universe as it is known today.

Greater understanding of the newly discovered dynamics of the QCD axion could potentially change the expansion history of the universe and thus inform the study of gravitational waves. Future work on this topic could also provide further insight into other enduring questions of fundamental physics, such as the origin of the tiny neutrino mass.

“Since theoretical and experimental particle physicists, astrophysicists, and cosmologists began studying the QCD axion, great progress has been made. We hope that our work further advances these interdisciplinary research efforts,” added Harigaya.

Press release here :-

Pre-print of paper "Axiogenesis" by Raymond T. Co and Keisuke Harigaya
here :-
Astronomers studying the Ophiuchus galaxy cluster, about 390 million
light-years away, have come to the realization that a cavity within
the cluster's plasma which had been detected previously with X-ray telescopes
betrays the radio fossil record of what they describe as the largest
known explosion in the Universe since the Big Bang.

The discovery was made using four telescopes; NASA’s Chandra X-ray
Observatory, ESA’s XMM-Newton, the Murchison Widefield Array (MWA) in
Western Australia and the Giant Metrewave Radio Telescope (GMRT) in India.

Press release here including images :-

The finding has been reported in a paper entitled ‘‘Discovery of a giant
radio fossil in the Ophiuchus Galaxy Cluster’, published in The Astrophysical
Journal on February 28th, 2020.

A copy can be found here at arXiv :-
Idy Golfman wrote:Did the 3.04 update and now no more H stating object is below horizon. Must be something I did wrong, no?


Hi Idy,


In order to compute where the local horizon is, you need to have set a local time zone and local time in SETUP DATE/TIME.
Keep in mind that time zones west of Greenwich, for example in the Americas, have negative time zones.
You also need to have an approximate latitude and longitude set in SETUP LOCATION.

After an alignment, when attempting to guide to an object below the horizon, the H annunciator should appear.

As the vented alkaline battery material is quite corrosive, it is important to clean it up as quickly as possible.

A little vinegar or lemon juice on a cotton bud can help neutralise the material.

We recommend to then additionally clean it with a cotton bud soaked with a good electrical spray such as CRC-226.

We also recommend you unfasten the screws holding the back shell of the enclosure on and check if any material has reached the circuit board.
Clean it in a similar way.

The white specks on the connectors are also indicative of a battery having leaked or vented. Again, use the same technique to clean them.

As all battery manufacturers recommend, remove alkaline batteries from equipment when it won't be used for an extended period of time.

Last week I returned from a two-week observing trip on the side of Mauna Kea on the Big Island of Hawai'i.

The trip was kindly organised by Dave Kriege of Obsession Telescopes who visits the island annually and keeps an Argo Navis equipped 22" Obsession UC stored there at a house of a Keck Observatory worker.

Our primary observing spot was at 9,200' (2,804 m) point on Mauna Kea. At that altitude, you are typically above the cloud tops but just below the point where altitude sickness becomes a potential issue for most individuals.

Night time temperatures typically hovered just above the freezing point but the freezer suit and woollen gloves I packed for the trip made observing comfortable.
I must admit if felt weird pack cold weather gear for a trip to Hawaii. smilie

Suffice to say the skies at that altitude on an island in the mid-Pacific whose relatively low population and enviable outdoor lighting ordinances are to die for. They are dark and transparent and the airglow
which is typically visible at the best dark sky locations at lower altitudes elsewhere on Earth is minimal.

The quality of the skies was first evidenced by the immediately apparent zodiacal light that extended up from the western horizon to perhaps 60 degrees elevation or more.
Caused by sunlight reflecting of particles of dust and ice in the solar system, as one of my observing colleagues said, if you didn't know better you would think there is a floodlit football stadium down there.

A couple of Sky Quality Meters gave SQM readings around the 22.18 on each night.

The summit itself where the observatories are is at 13,800' (4,205m) and it is recommend that visitors to the summit first acclimatise at the 9.200' point first for half an hour to an hour before proceeding.
At 13,800' the atmospheric pressure is 40 percent less than at sea level and Acute Mountain Sickness (AMS) is common. One survey revealed that some 69% of workers at the top of Mauna Kea
have experienced AMS at some point. AMS can be serious, including life-threatening conditions pulmonary edema (fluid in the lungs) and cerebral edema (fluid on the brain).
Thankfully a well-graded gravel road allows for anyone who experiences AMS to be rapidly evacuated to below 10,000' where recovery is typically quick.

We were lucky to be given a VIP daytime tour of the Keck I observatory and our visit corresponded to a beautiful day at the peak.
The first thing that strikes you when you get out of the car is the definite diminished amount of air to breathe. You have to take things easy. It had been snowing up there and stooping over and throwing a couple of snowballs
would leave one feeling as if you had just run up several flights of stairs.

The observatory has O2 blood monitors and a check of our party gave us all the reassurance we were within normal levels. Emergency oxygen is available on site.

We were also afforded a VIP tour of the Keck mirror lab at the observatory headquarters in Waimea. There we were able to witness the multiyear painstaking refurbishment of the 72 mirror segments that constitute the two 10m mirrors on Keck I and Keck II.
Each mirror is equipped with multiple levers and actuators. One set positions each of the segments into its appropriate position to form a parabola. A second corrects for small imperfections within an individual segment. A third can distort the mirror by
microns thousands of times per second as part of the laser artifical star driven adaptive optics system.

One of the most remarkable attributes of our 9,200' observing point was the rapidity by which would get access it. During the day, we stayed at a beautiful rental house at 1000' altitude where the T-shirt and shorts temperature
both day and night was always perfect. It was only a 15 minute drive from there to the beach. Yet we could drive from the house to the 9,200' observing point via a high-speed highway and road in under 45 minutes.

In fact the road up is reputed to have one of the most rapid rises in the shortest amount of time for any road in the world.

Those wimps who climb Everest only have to climb 12,000 feet to get from Base Camp to the summit. On the Big Island you could ascend or descend through 13,800' in under a couple of hours including time
to acclimatise.

With our observing site at +12 North and with two of us having come from Sydney and five from the continental United States, the Aussies of course tended to want to seek out northern targets, particularly large
galaxies and the Americans southern targets. Thankfully there was plenty of time over our two week stay to do both.

Once Crux had risen, it was possible to see both it and Polaris at the same time.

Even familiar targets such as the Trio in Leo took on a new, fabulous appearance, Each galaxy so fantastically bright and extended.

On one occasion we observed until dawn which gave us the opportunity to witness a beautiful, dramatic and memorable sunrise ascend up through the clouds below us.

On another night we had the opportunity to observe with local astronomy club members at a 6000' location. Several of the club members worked at the Keck and it gave us a wonderful opportunity to chat to them about
work there and life on the Big Island.

We also took a road trip to the top of Mauna Loa which is home to the Mauna Loa Observatory (MLO), which is the premier atmospheric research facility that has been continuously monitoring and collecting data related to atmospheric change since the 1950's.
This is the base station from which the Earth's ever-increasing CO2 levels are measured and depicted in the now famous Keeling Curve.
The one-lane, winding and undulating road to the summit of Mauna Loa goes through one of the most incredible landscapes on Earth, passing through vast solidified lava fields.


Hi Mike,

Apologies for the delay in my response whilst I've been away on an observing trip to Mauna Kea.

Attached is an unofficial and unsupported version of the User Manual Edition 11 in epub format for reading on a smartphone.

The document was converted using Cailbre and the formatting is not good but hopefully it will suffice for your purposes.

Hi Brooks,

Thanks for the post.

I had replied to your direct email via a cell phone whilst I was on an observing trip to Mauna Kea but I will also follow-up here for completeness.

The job of the lithium coin cell is to provide power to the time of day clock in the absence of any other power source.

It does not supply power to the non-volatile memory where the SETUPS are stored and that memory will retain its contents even when no power source exists.

We recommend you power the unit OFF when replacing the coin cell.
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