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Messages posted by: wildcard
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Hi Thad,

Thanks for the post.

Sounds like you are in the MODE ALIGN menu rather than MODE ALIGN STAR.

The MODE ALIGN STAR provides a convenient list of bright stars that you can scroll through with the dial.

The MODE ALIGN menu presents the last object you accessed either through MODE CATALOG, MODE IDENTIFY or MODE TOUR and like MODE ALIGN STAR, defaults to ACHERNAR (the
first bright star alphabetically in the catalog) when you power it on.

So if I were a betting man, odds are you might have been having a little 'finger problem'. smilie
We think in terms of an extended family of Argo Navis owners.

We were therefore deeply saddened to learn today of the passing of George Nikolidakis of Athens, Greece, in April this year.

George was only 59 and died after a battle with COVID-19.

President of the Hellenic Amateur Astronomical Union, I know he will be missed by his family and friends.

Our deepest condolences.

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place
Mount Kuring-Gai NSW 2080
Phone +61-2-9457-9049
Twenty years in the making, the Sloan Digital Sky Survey has released the largest 3D map of the Universe ever created, filling in the troublesome gap in the middle of 11 billion years.

Sloan Digital Sky Survey wrote:
The Sloan Digital Sky Survey (SDSS) released today a comprehensive analysis of the largest three-dimensional map of the Universe ever created, filling in the most significant gaps in our possible exploration of its history.

“We know both the ancient history of the Universe and its recent expansion history fairly well, but there’s a troublesome gap in the middle 11 billion years,” says cosmologist Kyle Dawson of the University of Utah, who leads the team announcing today’s results. “For five years, we have worked to fill in that gap, and we are using that information to provide some of the most substantial advances in cosmology in the last decade.”

The new results come from the extended Baryon Oscillation Spectroscopic Survey (eBOSS), an international collaboration of more than 100 astrophysicists that is one of the SDSS’s component surveys. At the heart of the new results are detailed measurements of more than two million galaxies and quasars covering 11 billion years of cosmic time.

We know what the Universe looked like in its infancy, thanks to the thousands of scientists from around the world who have measured the relative amounts of elements created soon after the Big Bang, and who have studied the Cosmic Microwave Background. We also know its expansion history over the last few billion years from galaxy maps and distance measurements, including those from previous phases of the SDSS.

“Taken together, detailed analyses of the eBOSS map and the earlier SDSS experiments have now provided the most accurate expansion history measurements over the widest-ever range of cosmic time,” says Will Percival of the University of Waterloo, eBOSS’s Survey Scientist. “These studies allow us to connect all these measurements into a complete story of the expansion of the Universe.”

Full press release here including images and four videos :-
Good to hear you were able to resolve it in the way you described.

In any case we would have helped you restore the correct date one way or the other, but if the ends justifies the means, your prescription was simple enough.

I must admit it still leaves me with a puzzle how it was stuck in that state. The code explicitly checks for the condition that if the year is less than 2000 at power on,
it sets the RTC date to JAN 1 2000 and reads it back to check that the change was made and reports an error it is not. You can leave to me as an exercise. smilie
Thanks for the post.

By way of background, there is an internal bit within the real-time clock (RTC) that determines what century it is set at.
If the coin cell becomes depleted, this bit can then go to zero which represents the last century.

However, each time it powers on, Argo Navis checks for this condition and sets the time to 1 Jan 2000 which includes setting the century bit to a 1.

Obviously it has not done this in this case.

To be honest, it is a strange condition and armed with a deep understanding of how all this works, one that would seem logically impossible,

However, we did have at least one report of it from a customer in December 2019 and they resolved it for themselves by upgrading the firmware,
the act of which in itself magically set things right. So it remained a mystery why it was not automatically being set at power-on otherwise.

If you have an Argo Navis serial cable and USB Adapter, you could try a couple of things.

Firstly, ensure the serial port you are connected to is running with a STARTUP command of 'navis' and a BAIUD rate of 38400.
Then start Argonaut and connect to the unit.

You should get a % prompt in the Argonaut terminal window when communication is established or if you press the PC enter key in the terminal window.

Then using the Argonaut Date/Time pulldown menu, select Set Date/Time. That will transmit the date/time from the PC to the unit and it might resolve it.

Failing that, use Argonaut and load Argo Navis version 3.0.4 firmware :-

That might also resolve it,

If it does not, email me at sales@wildcard-innovations.com.au and we can try and help resolve it. It certainly is unusual.

tomrgray wrote:Thanks for your suggestions. No joy on Serial 2, but have reconfigured serial 1 as you suggest and this appears to be working OK without usb cameras attached - I’ll test it tonight as clear skies. Does that mean there is a problem with Serial 2, dirty connection?

The laptop is an old Dell Latitude with Pentium M if you can still remember these. During lockdown I restored by original DEC Digital 386 25SL 2 Mb RAM and 40MB HDD and VGA display! I can still run my original Distant Suns from floppy disks...

Have a look inside the SERIAL 2 port under good light and magnification. Check that the contacts are clean and are all sitting in the same plane.

Also have a look inside the battery compartment and check if there has been any sign of a battery having leaked or vented in the past.

If you have a multimeter, put it in continuity mode or resistance measuring mode. Power the unit off. Use Appendix C of the User Manual to identify which is the SERIAL 1 GND contact.
Try and probe it and the GND contact of the External DC Power Port for low impedance. If there has ever been a short on the SERIAL 1 line, it may have blown the associated protective ferrite.
Hi Tom,

Thanks for the post and welcome to the forum.

The Argo Navis serial port communication is extremely robust and well tested, so it is most likely to be at the laptop end.

We've tested against Autostar extensively over the years but I just ran Austostar 3.18 on a Windows 2000 machine interfaced to an Argo Navis for half an hour and the connection didn't drop.

Make sure on the Autostar end in the communications dialog that you set parity to none and flow control to none.

I gather from your description the laptop has an in-built DB-9 COM port?

For the cameras drawing power from the USB ports, if the laptop manufacturer had complied with the USB specification, it should be able to
deliver sufficient power to them without interfering with the operation of anything else.

Given it is an older laptop though, is there any indication that is running out of grunt to process the data from the cameras and Autostar?
One test would be to disconnect the cameras and see if there is any improvement to the reliability of the serial comms.

Argo Navis serial ports 1 and 2 are independent and so another test would be to configure SERIAL 1 to run the 'meade' STARTUP command at 9600
and try swapping the cable to it.

Allen Grundmeier wrote:My name is Allen Grundmeier.

I just received my Argo Navis yesterday.
I'm taking it slow to make sure I don't assume that I know where I'm at in the set up process.

This is my question:

I've got a Win 10 computer. I'm trying to find the correct COM port as descriibed on pg (Com & LPT) ports as described on pg 169.

Allen Grundmeier
Robbinsdale, Minnesota

Hi Allen,

Welcome to the forum.

The Keypan USA-19HS comes with a CDROM with software on it. Be sure to install it first before plugging in the USB Serial Adapter for the first time.

The software on the CDROM includes the Window's device driver and a convenient utility called the Keyspan Serial Assistant.

On Windows 10, locate the "This PC" icon on the Deskop, right click on it and select Properties.

A dialog will open. On the left hand side of that dialog select "Device Manager".

Once the Device Manager dialog opens, follow the instructions in the Argo Navis Users Manual and drill down through the Ports (COM & LPT) hierarchy to determine the COM port
number Windows has assigned the Keypsan USB Serial Adapter and to change it to an unused port in the range 1 thru 4 if need be.

Alternatively, click on the Window's Start button on the lower left of the Desktop, left click on it and look for the Keyspan USB Serial Adapter folder.
Within it, select the Keyspan Serial Assistant. When the approval dialog open,s allow it to make changes to your computer. Select the Port Mappings tab and change the COM port that way.

Once you have assigned the USB Serial Adapter an port number of 1 thru 4, when you open the Argonaut software utility, select the corresponding number 1 thru 4 in the Port pulldown.
Then select Connection->Connect.

Hi Mikael,

Thanks for the post and the interesting question.

When the eyepiece is replaced by the much heavier camera, one of three things can happen.

1) The OTA drops in altitude but this drop is reflected by a corresponding change in the altitude encoder values.

2) The top end of the OTA "droops" in altitude as either the truss poles flex, the secondary cage shifts with respect the truss poles or the truss poles shift with respect the split blocks.

3) The camera itself shifts within the eyepiece holder.

I gather from your description you suspect the truss poles flex?

To eliminate 1) as the cause, dial up MODE ENCODER and whilst trying to accidentally nudge the OTA, note whether the altitude encoder values change when replacing the eyepiece with the camera.

Flexure of the truss poles as in 2) is a function of altitude with the maximum flexure occurring when the scope is pointed toward the horizon.
If the flexure is only small, that is within arc minutes, you might get away with a simple linear model.

One approach might be to create a simple TPAS model when the eyepiece is attached. Do a two-star alignment then sample say 6 stars using the SETUP MNT ERRORS functionality.
COMPUTE the model say using only the IE term and apply the model by selecting USE NOW.

When you replace the eyepiece with the camera, using the SET ERROR VALUES, IN USE NOW submenu, you could try changing the INDEX ERROR EL (ID) value to shift the apparent
pointing position in altitude. Perhaps with some trial and error you could ascertain a typical offset.

This approach might also work for 3).

One could also create a more dynamic offset, that is one that is a function of altitude, by creating a model that uses IE, ECEC and ECES, but finding suitable values would be more challenging.

I've never tried this, but the TPAS model and tweaking IE would be my first experiment if it were me. One assumes the shift is systematic rather than a sudden random shift.
I would be interested to hear how you get on.
erick wrote:Just catching up with the posts on this site. Wow Gary! What an experience. Congratulations. Eric

Thanks Eric,

As far as observing locations go, it is absolutely amazing.
Hi Didier,

The ServoCAT definitely won't respond to Meade protocol commands.

You can fill the Argo Navis FROM PLANETARIUM catalog entry either by connecting to the Argo Navis directly using the Meade LX200 protocol
or via the ServoCAT by a program with a servocat driver.

However, to initiate a GOTO from the planetarium, that can only be done by using a program with a servocat driver.

Otherwise if you use the approach where you directly interface to the Argo Navis using the meade protocol, you will need to press the GoTo button on the ServoCAT handpad.
Hi Dave,

One strategy is once you do perform an alignment is to then simply keep the unit powered on.
We have users with fixed observatories that leave their units powered on for days at a time.

Argo Navis allows you to align on any object at any time. You are not restricted to those in the MODE ALIGN STAR list, which is simply a list of convenient bright stars.

You can use the last object you selected in MODE CATALOG, MODE IDENTIFY or MODE TOUR in conjunction with MODE ALIGN (as opposed to MODE ALIGN STAR) to perform an alignment.

This includes a pseudo object whose J2000.0 RA/Dec co-ordinates you have downloaded into the FROM PLANETARIUM entry.

There are several ways to fill the FROM PLANETARIUM entry but for example, if you happened to be running the navis STARTUP command on one of the serial ports
and sent the command :-

fp `STAR1|12:34:56|+12:34|STAR|1.0|MY PLATE SOLVE STAR`

it would fill the FROM PLANETARIUM object with those RA/Dec co-ordinates and if you were then to EXIT out of MODE CATALOG and dial up MODE ALIGN, you could align on it.
Bonjour Didier,

The quick response is that in order to perform GoTo's you will need to interface KStars to the ServoCAT rather than to the Argo Navis.
However, I don't recollect if there is an INDI driver for the ServoCAT using "servocat" protocol and I would need to check.

What happens is that the ServoCAT relays requests for positions and tracking information to the Argo Navis from the PC.
May 29, 2020

Suraiya Farukhi, Ph.D., Universities Space Research Association wrote:
A Steaming Cauldron Follows the Dinosaurs’ Demise

Houston, TX and Columbia, MD—May 29, 2020. A new study reveals the Chicxulub impact crater may have harbored a vast and long-lived hydrothermal system after the catastrophic impact event linked to the extinction of dinosaurs 66 million years ago.

The Chicxulub impact crater, roughly 180 kilometers in diameter, is the best preserved large impact structure on Earth and a target for exploration of several impact-related phenomena. In 2016, a research team supported by the International Ocean Discovery Program and International Continental Scientific Drilling Program drilled into the crater, reaching a depth of 1,335 meters (> 1 kilometer) below the modern-day sea floor. The team recovered rock core samples which can be used to study the thermal and chemical modification of Earth’s crust caused by the impact. The core samples show the crater hosted an extensive hydrothermal system that chemically and mineralogically modified more than 100,000 cubic kilometers of Earth’s crust.

The lead author, Universities Space Research Association’s David Kring at the Lunar and Planetary Institute (LPI), explains,“Imagine an undersea Yellowstone Caldera, but one that is several times larger and produced by the staggering impact event that resulted in the extinction of the dinosaurs.”

The team found evidence that subsurface rivers of water were heated and driven upwards towards the boundary between the floor of the impact crater and the bottom of the Yucatán sea. The hot water streamed around the edges of an approximate 3-kilometer thick pool of impact-generated magma, percolated through fractured rock, and rose to the seafloor where it vented into the sea. The hot water system was particularly intense in an uplifted range of mountains on the seafloor that form a 90 kilometer-diameter ring around the center of the crater. The rock core recovered from that peak ring is cross-cut by fossil hydrothermal conduits that are lined with multi-colored minerals, some, appropriately enough, a fiery red-orange color. Nearly two dozen minerals precipitated from the fluids as they coursed through the rock, replacing the rock’s original minerals.

The peak ring of the crater is composed of fractured granite-like rocks that were uplifted from a depth of approximately 10 kilometers by the impact. Those rocks are covered by porous and permeable impact debris. Both rock units are affected by the hydrothermal system. “Hot-fluid alteration was most vigorous in the permeable impact debris, but garnet crystals, indicating high temperatures, were found at different levels throughout the core,” explains former LPI Postdoctoral Researcher Martin Schmieder who recently assumed a new post at Neu-Ulm University in Germany.

Minerals identified in the new rock core indicate the hydrothermal system was initially very hot with temperatures of 300 to 400 °C. Such high temperatures indicate the system would have taken a long time to cool. The team determined the cooling time using a geomagnetic polarity clock. "Our results indicate that tiny magnetic minerals were created in the Chicxulub crater due to chemical reactions produced by a long-lived hydrothermal system. These minerals appear to have recorded changes in the Earth's magnetic field as they formed. Their magnetic memories suggest that hydrothermal activity within the crater persisted for at least 150,000 years," says co-author Sonia Tikoo from Stanford University.

Further evidence for the hydrothermal system’s longevity comes from an anomalously high concentration of manganese in seafloor sediments, the result of seafloor venting. Co-author Axel Wittmann from Arizona State University explains, “Similar to mid-ocean ridges, venting from marine impact craters generates hydrothermal plumes that contain dissolved and slowly oxidizing manganese, which compared to background concentrations produced enrichments up to ten-fold in post-impact sediments over 2.1 million years at Chicxulub.”

Although the expedition only tapped the hydrothermal system in one location, Kring says,“The results suggest there was an approximately 300 kilometer-long string of hot water vents on the peak ring and additional vents scattered across the crater floor as impact melt cooled. Importantly, such hydrothermal systems may have provided habitats for microbial life.” Yellowstone’s volcanic hydrothermal systems are rich with microbial organisms and imply impact-generated hot water systems have the same biologic potential. Kring concludes, “Our study of the expedition’s rock core from a potential deep Earth habitat provides additional evidence for the impact-origin of life hypothesis. Life may have evolved in an impact crater.”

The extent and longevity of the Chicxulub hydrothermal system suggest that impact-generated systems early in Earth history may have provided niches for life. Thousands of these types of systems were produced during a period of impact bombardment more than 3.8 billion years ago. As each system cooled, it would have provided an environment rich in materials suitable for thermophilic and hyperthermophilic organisms.

Full story, including graphics, here :-

Full paper, "Probing the hydrothermal system of the Chicxulub impact crater" by Kring et. al. :-

Abstract, Kring et. al. wrote:

The ~180-km-diameter Chicxulub peak-ring crater and ~240-km multiring basin, produced by the impact that terminated the Cretaceous, is the largest remaining intact impact basin on Earth. International Ocean Discovery Program (IODP) and International Continental Scientific Drilling Program (ICDP) Expedition 364 drilled to a depth of 1335 m below the sea floor into the peak ring, providing a unique opportunity to study the thermal and chemical modification of Earth’s crust caused by the impact. The recovered core shows the crater hosted a spatially extensive hydrothermal system that chemically and mineralogically modified ~1.4 × 10**5 km**3 of Earth’s crust, a volume more than nine times that of the Yellowstone Caldera system. Initially, high temperatures of 300° to 400°C and an independent geomagnetic polarity clock indicate the hydrothermal system was long lived, in excess of 10**6 years.
May 29, 2020

Chandra X-ray Observatory wrote:
Astronomers have caught a black hole hurling hot material into space at close to the speed of light. This flare-up was captured in a new movie from NASA's Chandra X-ray Observatory.

The black hole and its companion star make up a system called MAXI J1820+070, located in our Galaxy about 10,000 light years from Earth. The black hole in MAXI J1820+070 has a mass about eight times that of the Sun, identifying it as a so-called stellar-mass black hole, formed by the destruction of a massive star. (This is in contrast to supermassive black holes that contain millions or billions of times the Sun's mass.)

The companion star orbiting the black hole has about half the mass of the Sun. The black hole's strong gravity pulls material away from the companion star into an X-ray emitting disk surrounding the black hole.

While some of the hot gas in the disk will cross the "event horizon" (the point of no return) and fall into the black hole, some of it is instead blasted away from the black hole in a pair of short beams of material, or jets. These jets are pointed in opposite directions, launched from outside the event horizon along magnetic field lines. The new footage of this black hole's behavior is based on four observations obtained with Chandra in November 2018 and February, May, and June of 2019, and reported in a paper led by Mathilde Espinasse of the Université de Paris.

Full story, images here :-

Paper at arXiv "Relativistic X-ray jets from the black hole X-ray binary MAXI J1820+070" by Espinasse et. al. :-
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