Monday, March 13, 2017

Using SkyTools 4 to Image the new Fragment of Comet 73P

I took this series of twenty 40-second exposures on February 13 using iTelescope T30 in Australia. The exposures covered about 15 minutes in total. When made into a movie, they show the comet and its new fragment moving across the sky.  

Not a Fragment of his Imagination
On February 10th Thierry Noel circulated an image that revealed a new fragment ofcomet 73P, apparently trailing behind the main body of the comet. This new fragment was quickly confirmed and designated 73P-BT. 

I set about to observe it myself, with the idea in mind of checking for other possible fragments, and this is how the movie above came about. The seeing was poor that morning in Australia, there was moonlight, and the flat field went awry (I'm still looking into why), but the series of images served their purpose. As far as I can tell from the movie, there are no other new fragments nearby.  On the right is a stack of the same images in the movie, but with the stars trailed. 

How I Planned my Observation using SkyTools 4
When I first saw the post by Thierry Noel, I first did a quick check to see if there were known asteroids or comets shadowing 73P, perhaps posing as a fragment. This was a simple matter of opening the SkyTools Interactive Atlas, centering 73P, and setting the UT date to that of his image. As I suspected, there were no comets or minor planets near the position of the fragment. 

My next thought was to act quickly to confirm his observation. Through my subscription I have access to 20 different telescopes located around the planet. But this posed a problem that needed a quick solution: which of the 20 telescopes at my disposal was the best one to use? 

Using SkyTools 3 I could switch between different locations in the Nightly Planner, looking for the one that gave the best view. But I still needed to pick a telescope, and that would mean comparing fields of view, resolutions, and sensitivity. Once I picked a telescope, I'd still have to calculate the motion of the comets, in pixels, to determine the maximum exposure I could use before the comets began to trail. That is still quite a bit of work. Ah, but I have an advantage. I am currently the only person in the world with access to the nearly completed SkyTools 4, and it has an awesome new tool to help choose a suitable telescope quickly and easily:
Above is a screen capture from the Compare Imaging Systems tab of the SkyTools 4 Object Info, set for 73P on the Night of February 13/14. The first thing it does is to select the optimum image scale for each Imaging System (telescope+camera) by varying the available focal reducers/extenders and binning. Then it selects the most appropriate filter. Maximum observing times, image scales, and exposures are tabulated, and the list is sorted so that the best systems are put at the top. 
The columns are as follows:
  • Observing Timethe total time that the comet is observable from the location of the telescope. This is affected by the latitude of the telescope and how low to the eastern horizon the telescope can be used. T27 in Australia can observe the comet for 70 minutes, but T24 in California offers only 15.
  • Exposure TimeThis column displays the total exposure time required to reach the target Signal to Noise Ratio (SNR) which I had set to 80. It allows us to compare exposure times between systems. 
  • Scalea parameter that describes the quality of the image scale, from 0-100. Forty is considered good. As you can see, the comet has a poor scale on all of these systems, but some are better than others. Regardless, we aren't likely to detect features in the coma or determine if the new fragment is really a cluster of smaller ones.  
  • Sizethe size of the coma of the comet in pixels on the image. This is of course related to the Scale parameter. 
  • Resolutionthe expected resolution of the image in arc seconds. This considers the quality of the astronomical seeing (that I have selected elsewhere as excellent) and the airmass of the comet during the exposures.
  • Trail Timehow long you can expose before the comet starts to trail on the image, or if we are tracking the comet, this is how long until the stars begin to trail. 
  • Fltthe optimum filter to use. Once you have selected a system you can decide to explore the use of other filters as well, perhaps for a color LRGB image.
  • Focusthe selection of focal reducer/extender (not variable for these telescopes).
  • Binsthe optimum binning, selected as a compromise between image scale and exposure time.
The available observing time for T24 was too short, and T27 wasn't available. I ultimately chose T30 for my observation. For T30 the coma would cover 24 pixels and it could reach an SNR of 80 in 5 minutes, which seemed like a good combination.

Have a look at T07, which is located in Spain. This system would require much longer to reach the same SNR, likely because there is no Luminance filter available. With twenty telescopes, it is nice not to have to remember things like that.

I knew I wanted to make a movie, so I didn't want to track the comet and trail the stars. Instead I wanted to take a series of shorter exposures, limited by the time it would take for the comet to trail from its motion across the sky. So the next thing I did was to use the SkyTools 4 exposure calculator to make sure that the SNR I could expect in a 40-second exposure, on that morning, with T30, would be high enough, and it was. 

To complete my planning I created a SkyTools 4 Imaging Project that defined what I wanted to do. Then I entered the project into the Scheduler for the night of the 13/14th and it generated a plan for ACP Planner, which is the control system used for the iTelescopes. The observing time was scheduled and the plan was uploaded to the telescope, and there you have it.

I can't wait to share SkyTools 4 with everyone. I believe it will revolutionize the way people plan their imaging, and not just for those who use remote telescopes. What if you only have one telescope? Well, consider this: the same calculations that made the imaging system comparison tool possible can be used to answer other interesting questions. For example, imagine you just bought an OIII filter and wanted to observe an emission nebula. Which ones should you try for? E.g. which nebulae are strong in the OIII and are suitable for your telescope and location?  SkyTools 4 has the answer to that question.

Wednesday, November 30, 2016

The SkyTools 4 Scheduler

Recently I needed to make a screen capture of the SkyTools 4 Scheduler tool, and thought I would share it with others as well.

Please keep in mind that this is my unfinished working version and that I didn't spend much time creating the example.

So what are we seeing? This is the SkyTools 4 Professional Edition in Imaging mode. When in imaging mode all tools are customized for imaging, from the planner, to the charts, to the Object Info. It is as if there are two separate versions of SkyTools, one for visual observing and one for imaging. In this way the tools can be specifically designed for visual observations or imaging, without attempting to do both simultaneously.

The Scheduler is used to generate a schedule for observations to be made on a given night. The result might be a schedule to be carried out manually, via Real Time, or it can be a formal plan to be used via a robotic telescope.

At the top of the dialog the iTelescope T21 imaging system has been selected. An Imaging System is more than just a telescope. At a minimum it consists of a telescope OTA + camera + mount.  But it also defines filters, acceptable exposure times, an optional fixed location, focal extenders/reducers, slew speeds, camera readout times, etc.

On the left are the imaging projects that have been created for this imaging system.  An Imaging Project defines how we want to observe each target. It is the heart of SkyTools 4 imaging.  I am not quite ready to show The Imaging Project dialog yet. An imaging project describes the filters to be used, what the exposure targets are for each filter, an observing priority, the positioning of the field of view, optional multiple fields of view to form a mosaic, binning, etc. The project is also used to track progress and to archive your observations.

The schedule is built on the right. It can be built automatically or one target at a time. Each observation includes a start time, filter, sub exposure time, and number of sub exposures. The schedule presented in the example is incomplete. Projects would normally be observed for longer periods of time, and normally there would be more of them to choose from, filling the time allowed.

Under the NightBar are two visual aids. The one directly below the NightBar indicates the quality of the imaging opportunity for the selected imaging project, in this case a project called P9 D. Green is the prime time to image it.  Below this is a visual depiction of the schedule. Green indicates observations, red indicates telescope slews. The spaces in between are where additional imaging projects can be scheduled.

The imaging system in this example is a remote robotic telescope that uses ACP planner for control. When you click Create Plan an ACP plan is generated from the schedule. This plan is uploaded and the observations are made accordingly. Time on this telescope is expensive, so normally we would build a plan for part of the night rather than for all of it, and every minute would be used.

Wednesday, July 15, 2015

All These Worlds are ours to Explore

Pluto is a World

Perhaps people should start thinking about Pluto as a world, rather than a planet. I think that’s what most people really mean anyhow. Our solar system is full of worlds—beautiful and strange places that Captain Kirk might want to beam down to. 

To the ancients a planet was a star in the sky that moved. There were five of these in all: Mercury, Venus, Mars, Jupiter and Saturn. They looked just like any other star, but they wandered around the sky as the days, weeks, and months passed. That alone was enough to make them special.

When, in the early 1600’s, Galileo turned his telescope on the sky, he discovered a sixth planet: the one beneath his feet. Galileo’s observations showed that the earth is not the center of the universe, but just another planet orbiting the sun.

In 1783 the astronomer William Herschel discovered Uranus. Although too faint to be seen by the eye alone, he knew immediately that it was no mere star, because it appeared as a small disk in his telescope. Sure enough, as the nights passed, it too wandered. This was the seventh planet.

In 1801, the Italian priest, mathematician and astronomer, Giuseppe Piazzi, discovered the eighth planet: Ceres. Yes, Ceres. Ceres was heralded as a major discovery, for it was found right where astronomers expected it to be, in the big gap between Mars and Jupiter. A year later another similar planet was discovered, named Pallas. Then came Juno, Vesta, and Astraea. If you had studied astronomy in the early 19th century you would have been taught of the 11 planets in our solar system. What an exciting time it must have been, with all these newly discovered planets. But there seemed something amiss with these new planets. Astronomers had expected one big planet in the gap between Mars and Jupiter, but they had found five. Based on how faint they were, these new planets also seemed to be quite small. There was some debate as to whether they were planets at all.

It all came to a head in 1846 when Neptune was discovered. Neptune was another major planet that was found way out beyond Uranus. In 1847, after nearly 50 years of being called planets, Ceres and its compadres were redesignated Asteroids. As many had come to realize, these asteroids were more akin to planet fragments than true planets. So once again there were only eight planets, and as the years passed many more asteroids were discovered. They number in the hundreds of thousands today.

Another fifty years passed. School children became used to the eight planets of the solar system. But astronomers wondered if there were yet more major planets to be discovered. They searched ever deeper into the outer reaches of the solar system, and as the 20th century dawned, Percival Lowell, a man who was flamboyant and wealthy, began a quest to discover what he called, “Planet X.” It took some thirty years, but eventually an astronomer named Clyde Tombaugh, who was employed to pursue Lowell’s dream, found a new wandering star. This was hailed as the first great new planet discovered in the 20th century. Pluto/Planet-X was expected to have a mass of ten Earths, and it was far beyond the region of the asteroids, so few questioned that it was a planet. But this turned out to be hubris. The calculations that had predicted planet X had been in error, and Pluto had been found quite by accident. By 1940, estimates put it at about the same mass of the earth. By the 1970’s, estimates of its mass had shrunk to 1/10 that of the earth.  Pluto was shrinking, if not in reality, at least in the estimation of those studying it. By 1980 it was a mere 2/1000th the mass of the earth. Pluto also has a weird orbit that brings it within the orbit of Neptune for part of the time, and is tilted by a whopping 17o. People started to realize that, like Ceres, Pluto may not be a proper planet, but there was no compelling reason to change its status.

At the dawn of the 21st century, an astronomer named Mike Brown realized that there were likely more objects like Pluto out there, and much like his predecessors, he set out to find one. He and his team eventually discovered many such bodies, including Quaoar, Sedna, Orcus, Haumea, Makemake, and Eris. Eris is big—about the same size as Pluto, but more massive. By 2006, astronomers realized that the Ceres saga was playing out all over again. Rather than call all of these new Pluto-like objects planets, it was decided by the International Astronomical Union to remove Pluto as a planet in much the same way that Ceres had been. In addition, a new class of objects was created, called Dwarf Planets. These objects include Pluto, Ceres, Eris, and a growing list of others in the outer solar system. 

Once again, there were eight planets.

If you look at the question of what constitutes a planet from an historical perspective, a case could be made for only the original five wanderers. Wandering star is, in fact, what the word planet means. Perhaps it all went wrong with Galileo, when people realized that they were living on a planet. After all, the earth is not a star that wanders in the sky. Or perhaps it went wrong when Uranus and Neptune were called planets. Even though they are both large and massive, they are too faint to be seen wandering with the eye alone. It certainly went terribly wrong with planet Ceres, which would have led us to hundreds of thousands of planets and counting. Alas, Pluto has suffered a similar fate. 

Something profound has happened since people first followed the paths in the sky of planets—these wandering stars. We have come to know them as places--places you could visit, with mountains and valleys. Science fiction has depicted them as places where you can land your ship and walk around. In fact these are all worlds to be explored. These worlds include not only Pluto, but Ceres, and Vesta, our Moon, and many of the moons of Jupiter, Saturn, Uranus and Neptune. Even Pluto’s moon, Charon, is a world waiting to be walked upon. All of these worlds are so much more than wandering stars in the sky; they are places for us to explore.

Perhaps we should start thinking about them as worlds rather than planets, and we can skip the scientific definition. After all, we all know a world when we see one.

Wednesday, September 3, 2014

Dell Venue 8 Pro Review

Over the summer I purchased a Dell Venue 8 Pro tablet. This is a $200-$220 8-inch tablet that runs full Windows. It is small, thin, and lightweight. I carried it with me on my travels, including campouts, my family vacation and ultimately to the Oregon Star Party, where I used Powerpoint and ran a SkyTools demo on it. It runs SkyTools 3 quite well and, with ASCOM, it will control most any telescope. In fact, there was a gentleman at the OSP using one to drive his 40-inch Dob. He had it attached to the base of the telescope itself, and it was working quite well for him.

It is possible to connect to the telescope via a USB connection, but using a Bluetooth-to-serial adapter may be an even better option, assuming it works (I have not tried this personally).

As others have reported, the Windows touch interface allows SkyTools to work mostly as it would using a mouse (with a few exceptions, such as mousing-over objects on the screen). I must say it's pretty cool to have such easy access to SkyTools in the field.

On the downside, the screen is very small and the video driver does not currently allow you to enlarge the fonts by more than 25%. You need to look pretty closely at it in order to see what is going on, and those with failing vision may find it difficult. In that case, one may wish to go to the larger 11" version. It also can't handle a very heavy load, so it is best to keep your observing lists short, particularly with Real Time, which will keep things rolling along nicely.

It seems clear to me now that this is the future for SkyTools in the field. When it comes to supporting many different mounts, and advanced features, telescope control via ASCOM is difficult to beat, and it runs on Windows. Windows will continue to improve in terms of integrating the touch interface, and there are new processors on the horizon that will be smaller, more powerful, and run longer on a small battery. We may even see some of these things emerge in the coming months. For my part, I am working to make ST4 more compatible with the touch interface, without sacrificing any of the unique capabilities of the mouse.

Thursday, August 28, 2014

The Imaging Project and the Oregon Star Party

I was recently invited to be a speaker at the 2014 Oregon Star Party. The story of how this came about began last April. I was thinking about the new astro-imaging features that I was adding to SkyTools 4; things like support of image mosaics, generating scripts for automated telescopes, and some sort of image logging. I had in mind about a half-dozen separate features and I wasn't sure how to put them all together.

So there I was, idly pondering the differences between visual observing and imaging. Visual observing is relatively simple to plan: figure out when the best view is going to be and go look. Unless you are doing a detailed sketch, looking doesn't take all that long. But imaging can entail long exposures in multiple filters and even include different positions in the sky for a mosaic. Imaging an object is less like a casual rendezvous, and more like a project. That's when it occurred to me: visually we simply observe celestial objects, but when doing imaging, we should be observing projects.

This idea of an imaging project was like a revelation. I could see how all the imaging features that I wanted to add to SkyTools 4 could all come together. In fact, I could use this idea to create an observing system for imaging rather than simply present a set of disparate tools.

I was excited to say the least. Ideas that bring everything together don't come along every day. On that same day, I was contacted by Mark Martin of the Rose City Astronomers, asking if I would be interested in speaking at the Oregon Star Party. My first answer was that I didn't have anything to talk about, but when he persisted, my excitement about the imaging project idea got the better of me and I accepted his invitation to talk about it. After all, it was April and the OSP wasn't until late August. I had plenty of time to figure it all out.

First I had things I needed to finish that I didn't want to leave half done. Then summer came along and I found myself spending a week in Texas at a scout camp with my boys, and soon after there was a family vacation. Before I knew it, the OSP was only a month away and I had nothing. Absolutely nothing! Not only was there no code to demo, but I hadn't even figured out the details.

After the panic wore off a bit, I got down to work. I went at it for long hours, seven days a week. I also had to prepare a talk, so I combined my work on the overall software design with developing the notes for my presentation. Doing so was odd, but in fact it worked quite well. I chose one part of the new code to focus all my efforts on so I could demo it, redesigning and coming up with new ideas as I went along. In concert, I worked the ongoing story into my presentation. In the end the talk was probably a bit too ambitious, but overall it seemed to go ok.

I really enjoyed being at the Star Party and meeting lots of new people, although it was rather painful to be there under such beautiful dark skies without my telescope. Fortunately I did mooch some great views, including an unforgettable view of M51 in a 40-inch Dob.

Wednesday, October 31, 2012

SkyTools and Windows 8

I haven't posted here much recently, but that is likely to change in the coming months. So to start things off...

With the release of Windows 8 it is time to say a few things about the impact Windows 8 will have on SkyTools users, now and in the future.

First and foremost: SkyTools 3 will continue to work on the Windows 8 desktop just as it has with Windows 7. We have found no compatibility issues. If you are still running ASCOM 5, I do recommend upgrading to ASCOM 6 prior to upgrading to Windows 8.

Windows 8 and the Future
Windows 8 brings some major changes. A lot of confusing things have been written and said about them. The difficult thing to grasp about Windows 8 is that it is at once a bold new operating system, and at the same time the old Windows 7 we are familiar with. This is important to keep in mind when you hear or read broad sweeping statements about it.

Imagine if Microsoft released a whole new version of Windows with only one change: a redesign of the Start button. For most current desktop/laptop users this is all the upgrade to Windows 8 will initially represent. The Win 7 Start button opens a menu that lists all of your programs and is used to start them. In Windows 8 the Start menu has been turned into a full-screen with icons that you use to start programs. Once a traditional Windows program is started you go right back to the desktop. What startles people is that they are greeted by this new Start screen when the computer is booted rather than the familiar desktop. By doing this it literally throws the new Windows features "in your face." But rest assured, the Windows desktop is still there.

In addition to replacing the Start menu, the new screen also launches a new kind of Windows program. These programs are optimized for the touch screen, although a mouse will still work fine, and are meant to be used full screen, like a game, the SkyTools Interactive Atlas, or the "apps" that we have become used to on phones and tablets. The point of all this? It enables tablets and other touch devices to run Windows 8.

Microsoft has made new versions of most of their software, such as Office, Mail, etc, that work with the new interface. Many other developers are in the process of creating similar programs. This leaves developers such as myself with a quandary. Some say that this new "Modern UI" interface is the future and the old Windows desktop will ultimately be replaced, in the same way that DOS was replaced by Windows itself. But I'm a little skeptical about that. It may be that the new interface will not be powerful enough for certain types of applications--those driven by the precision that only a mouse can provide.

An example of what I'm talking about is the way that SkyTools identifies objects as the cursor passes over them. This obviously isn't possible without a mouse. On the other hand, a touch-based Nightly Planner would provide a natural jumping off point for opening charts, logs, and other SkyTools functions. It would also provide a great way to control a telescope in the field.

At the moment the way forward for SkyTools is not yet completely clear. Will it continue to be a desktop program or be ported to the new interface? I can say this for the near term: there will be "companion apps" for SkyTools that use the new interface for use in the field on tablets and other touch devices. But only time will tell if the entire program will eventually be ported to the new interface.

New Windows 8 Hardware and SkyTools
If you are purchasing a new Windows 8 tablet, it is important to be aware that there are two "flavors" and what the differences are. The less expensive "Windows RT" tablets only run programs written for the new interface. They will not run SkyTools 3! These tablets will eventually run the SkyTools "companion apps" which will be available for the next full version of SkyTools.

The more expensive tablets/convertibles will offer the full version of Windows that desktop users have. These will run SkyTools 3 on the traditional desktop.

Should You Upgrade?
Some people are going to hate Windows 8. There is no question about that. I think it comes down to how you approach change. An example of something that is bound to drive old timers like me nuts is the way the Esc key doesn't back out of the new-style programs as we might expect it to. Instead, we are going to have to accept that the "Start/Windows" key (which I personally have ignored for years) is going to become our new friend. Still, I did eventually get used to it (after a few hours spent cursing). There are also times when using the new interface that you will think, "I could have done that with a lot fewer movements and clicks!" But I have found that in most of these cases there are ultimately better ways to do the task, such as a keyboard shortcut. It is often my natural desire to do things the way I'm used to doing them that is the cause of most of the trouble.

Some have claimed that Windows 8 will have big problems like Vista did, and it is popular to claim that they won't have things ironed out until Windows 9. The reality is a bit more subtle than that. On the desktop things are pretty solid, although there are some weird issues that crop up. One of my computers didn't shut down properly using the Windows 8 preview version (there was an easy work around) and sometimes system error messages appear on the desktop where you can't see them. But in general I don't believe that upgrading a desktop/laptop to Windows 8 will cause people anywhere near the problems they had with Vista. This is primarily due to the fact that for most users it's really still Windows 7 under the hood. When Vista appeared I counseled people not to upgrade their existing XP machines, but I see little reason not to upgrade to Windows 8, particularly when it can be easily done as a download for $40.

On the other hand, the picture may not be so rosy for the new Windows RT tablets. This is where most of the new aspects of Windows are concentrated and it has had the least testing on this hardware, so this is where people will likely see the most trouble. At the moment there aren't enough quality apps available to make these tablets as useful as they should be. As an example, Microsoft's Mail app doesn't have many of the features people expect, crashes constantly, and I was not successful in getting it to send mail to my outgoing mail server. On a desktop/laptop many other options are available, but I feel a bit sorry for the early adopters of Windows RT tablets. I'm looking forward to owning one of these myself, but I'll wait until things are sorted out.

Although I've been testing the new OS for months, the first computer that I officially upgraded was my laptop. It does boot a bit more quickly and runs a bit faster. Overall I'm happy with it. Multi-monitor support has been improved and I like the new Task Manager. But for many there may not be any compelling reason to upgrade right away. This is the future of the PC, and only Windows 8 will give us access to the new software designed for the new interface. It's sort of like having a new toy added to the old OS. But some will see it as a useless appendage that only gets in their way. There are also the inevitable problems and annoyances that come with any major change to your computer. In the end, the most compelling reason to upgrade an existing desktop/laptop in the next few months is that the $40 upgrade may only be available until the end of January.

Personally, I would certainly go ahead and purchase any new computer with Windows 8 pre-installed.

Regardless, I urge even the most tech savvy to review the basics of the Windows 8 interface before trying to use it. This will make the transition go a lot more smoothly.

Tuesday, February 16, 2010

Going to NEAF

It's been a while since my last post here. Despite the slow economy SkyTools 3 is still going very strong and I couldn't be more pleased. I am in the final stages of the release of a major update to version 3.1, which adds some minor new features, fixes some annoyances, and makes the program even more stable than it already was.

Yesterday I received my copy of the April 2010 Sky & Telescope, which (finally!) has a review. It was well worth the wait because they did a very nice job on it. In the past they sent a copy out for review to someone who was not familiar with the program and they didn't always get it. Their review for SkyTools 2 was titled, "A 20th Century Log Book." No-seriously! I didn't know about the review before hand and happened to pick up a copy of the magazine. I read past the first paragraph before it slowly dawned on me--with a sick feeling in my stomach--that it was a review of my software. That, and they didn't give it much space. To add insult to injury, the very next issue had a comprehensive review of Megastar (a competitor) written by someone who uses the software regularly--someone who got it. To make matters worse it was a relatively minor upgrade to Megastar whereas I had pushed forward with all these cutting-edge features for SkyTools. Let's just say my blood pressure got a little up over the whole thing. Thankfully this time the review did a wonderful job of describing what SkyTools is.

Mrs. Skyhound and I are going to attend NEAF this year. We only made it out once before, I think in 2001, so it has been a long time. We are really looking forward to seeing everyone. If you attend, please come by and chat.