Announcing Deep-Sky Planner v9.2.3.0 Update

Knightware is pleased to announce the release of a free update to Deep-Sky Planner 9. This update includes an important enhancement - additional support for ASCOM 7. DSP9 has been tested with the Omni Simulator included in ASCOM 7.1.3. If you have problems with Deep-Sky Planner and an ASCOM 7 driver for a telescope mount, please contact Knightware.

The Deep-Sky Planner 9 Trial Edition also has been updated with support for ASCOM 7. You can find it at https://knightware.biz/dsp/trial.htm

To those who have asked about support in Deep-Sky Planner for the ZWO Seestar line of telescopes, development and testing are underway with a Seestar 50. It appears that the Alpaca server in the S50 will require an updated ASCOM driver from ZWO, or direct support for Seestar Alpaca without ASCOM. I am waiting for an official release of an updated ASCOM driver from ZWO and am working on direct support for S50 Alpaca 

Announcing Deep-Sky Planner 9.2.2.0 update

Knightware is pleased to announce the release of Deep-Sky Planner v 9.2.2.0.   This update fixes a recent issue involving DSS image downloads. Recent changes in Windows 11 and at DSS image servers (STScI, Skyview, SkyServer, CDS) *require* https: requests. This is a security change made at the servers.

Deep-Sky Planner has used unsecured http: requests for years, but servers now require secured https:. An effort has been made in this update to fix requests. If you have trouble downloading or viewing DSS images in the details pane of a document, you can click 'Get DSS Images'. This will use will use the repaired link and download the image.

If you have further issues with DSS images, please notify Knightware using as much detail about the problem as appropriate.

Announcing Deep-Sky Planner 9.2.0.0 update

Knightware is pleased to announce the release of Deep-Sky Planner v 9.2.0.0.  This free update to version 9 has 2 minor enhancements. First, the Deep-Sky Planner desktop window is saved and restored on the primary monitor. This feature disappeared when Microsoft and my development tools maker made changes to accommodate high resolution monitors and systems with multiple monitors. Constant changes and poor documentation are the reasons for the delay in the enhancement.

The second change is intended to help users that install Deep-Sky Planner 9 for 'All Users' of a computer. Microsoft has made security changes in the last few months that tightened security for such users. 

Note the change in v 9.2.0.0 still offers the 'All Users' choice when Deep-Sky Planner is installed originally (ie, v 9.0.0.0). Deep-Sky Planner now warns users of an 'All Users' installation of potential problems or end execution for more extensive security issues.

The remedy for the 'All Users' problem is either 

1. Uninstall and reinstall Deep-Sky Planner 9 for 'Just Me'. This has always been the recommended choice for installation and it avoids security issues because any user of a computer cannot access the program or its resources.
2. Run Deep-Sky Planner as administrator if the software must be installed for 'All Users'.  This also avoids security issues IF the administrator of the system permits running apps as administrator.

Choose Users install screen

New Use for SQM Readings

Knightware's SQM Reader Pro 3 software has been updated recently, gaining an important new feature for users that want to contribute sky brightness readings from Unihedron's Sky Quality Meters to researchers.

The latest update provides the ability to upload readings directly to the Globe at Night Sky Brightness Monitoring Network (GaN-MN). The data are collected and curated for accuracy and stored in a database so that it can be shared with researchers worldwide. The data are used by researcher in various disciplines such as  astronomy, human biology and animal migration, for example. Unihedron's Sky Quality Meters and Knightware's SQM Reader Pro 3 provide off-the-shelf tools that make collecting and submitting data a snap.

SQM Reader Pro 3 Upload to GaN-MN

As the body of sky brightness data grows, we can also track the progress of light pollution mitigation efforts. As municipalities consider their lighting ordinances, the sky brightness data can provide an objective reason to update or reduce lighting.

If you want to participate in the Globe at Night Sky Brightness Monitoring Network, you can get more information by contacting globeatnight.network@gmail.com (or gan-mn@qq.com for users in China).

Knightware would like to thank both Dr. Chu-Wing So (The University of Hong Kong) and Ms. Amy Jackson, M.S.T. (Director of Starry Sky Austin- Astronomy and Dark Sky Education and Conservation, IDA Texas- Central Texas Regional Manager) for their assistance in developing and testing the GaN-MN data submission feature.

Deep-Sky Planner Mobile Edition: Project Update

Users of Deep-Sky Planner Mobile Edition (DSPME) haven't seen an update to the Android app in many months while users of the iOS/iPadOS app have. The changes made in the past year have affected only the iOS/iPadOS app so the Android app didn't require updating.

That situation has changed recently. Both mobile apps provide access to Cloud Storage services Dropbox, Google Drive and OneDrive. These services have changed authentication for their services which have required changes to the apps. Updating the apps has been complicated by the fact that the development tool used to produce the apps (Embarcadero C++ Builder) has not updated its Android app support ¹. I can still develop the app for Android but I can no longer distribute it through the Google Play Store. I can still develop and distribute the iOS/iPadOS app through the Apple App Store. There is no issue there.

After months of research, I have decided to make the Android app available to the astronomy community directly from the Knightware website. I have also decided to make the app free of charge. The downside of this for users is that they are not notified by the Google Play Store when an update is available. Furthermore, the app also must be 'sideloaded' onto Android phones and tablets. This presents several warning messages about installing an app from an unknown source. In this case, this means that the app is digitally signed by Knightware but NOT delivered through the Play Store.

What about the Apple (iOS/iPadOS) app?

The iOS/iPadOS app is not affected by the change in distribution - you can still get the iOS/iPadOS app from the App Store and it will continue to have a small price. (There are ongoing expenses required for distributing an app through the App Store.)

Each app will continue to be available and will be updated as necessary. Learn about the Android and iOS apps at https://knightware.biz/dspme/index.htm

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¹ The the Google Play Store requires that all apps be compiled for 64-bit hardware. Embarcadero does not ship a 64-bit C++ compiler for Android at this time. A 32-bit C++ compiler for Android is shipped and has always been used to produce DSPME for Android. Note that a 32-bit app runs on a 64-bit phone for example. The Apple App Store also requires 64-bit apps and Embarcadero ships a 64-bit C++ compiler for iOS/iPadOS.

What's brewing at Knightware

First and foremost, we are well and hope you are too. I have heard from several users about friends or family that have had COVID-19. It has really brought home the fact that it is everywhere. Please be safe.

Because Knightware's spring travels were canceled (including NEAF), there has been more time in the office and less on the road. I've missed seeing users but I've gotten a lot done. For example, I've been updating equipment lists in the Community. Take a look and see what's new. I plan to continue updating equipment data over the summer (I'm in northern hemisphere: North Carolina, USA).

I've also updated Deep-Sky Planner Mobile Edition for iOS and iPadOS recently. The app was not broken, but Apple announced some new requirements that needed attention.

Updating DSPME on the App Store

I am still waiting for an anticipated update to my development gear that will allow me to address new Google requirements. It also is not broken but the Android app needs some updates.

Since I have just received a major upgrade to my compiler and libraries, I am busy changing Windows and mobile software to use the new compiler and libraries. Thankfully, things are going smoothly but there is much to do. Stay well!

DSP Mobile Is Here!

Deep-Sky Planner Mobile Edition has been submitted to Apple and Google for review! Any issues identified by their processes will need to be addressed before the app is released to the respective app stores.

[Update: DSPME is now available from both Apple and Google ]

What to expect

Users will receive a native code app (not a web app) that runs on Android 4.4+ and iOS 11+. The app has been adapted to fit both tablet and phone form factors. The phone-sized screen is packed with data and special user interface capabilities to help present the data in a usable way. The additional screen space of tablets is also used to advantage.

The native code app performs ephemeral calculations so that you know where objects are in the sky at any time and place. These ephemeral calculations provide other advantages too like accurate double star ephemerides; planet, sun, moon, asteroid and comet ephemerides; predicted extrema for variable stars. Along with all of these ephemeral calculations comes real-time data filtering and sorting.

The entire Plan and Equipment Libraries are available to the app so there is no shortage of observing resources. Please stay tuned for updated status.

Home screen in night vision style, iPad 9.7"

Plan screen in night vision style, Samsung Galaxy S7 Android phone

Plan screen in Wedgewood style, iPhone 6s

Plan screen in Calypso style, Nexus 7 Android tablet

Plan Library screen in BunkerGray style, iPad tablet

Cloud Import screen in BunkerGray style, iPad tablet

DSP Mobile: Test Progress

Testing of Deep-Sky Planner Mobile (DSPME) has been underway for several weeks. All app features have been implemented so testing is focused on bugs and usability issues. We have been working mostly with tablets so far, but adjustment for phones is underway.

Community screen on Android phone

The attached screen shot shows the latest observing plans uploaded to the Deep-Sky Planner Community. You can read more about this feature in our previous post.

We have found that a small tablet is perhaps the best form factor (device size) for the app. Small tablets have enough 'screen real estate' to show details while remaining small enough to be held conveniently. Small tablets currently used in testing include the 8" Samsung tablet and the iPad Mini.

We will continue to adjust the user interface for usability on phones. An update on that progress will follow in a week or two.

DSP Mobile: Plan & Equipment Libraries

As mention in an earlier post, Deep-Sky Planner Mobile Edition (DSPME) allows you to browse and import plans from the Plan Library in the Deep-Sky Planner Community at knightware.biz. This post discusses this and the ability to import equipment lists from the Community.

Accessing plans and equipment lists (resources) online is a simple process: first, you download a list of available resources, and then you can download the resource and store it on your device. Any of these resources can be deleted later if you like.

[Note: Screenshots for this post were made on a 10" iPad tablet with the BunkerGray app style. The Community is running on a test server.]

The Latest Plans in the Community

You can scroll through the list of plans to review them, and tap Get when you want to download one. The plan is stored on your device and can be opened with Plans on Device.

Browsing and downloading equipment lists works similarly. The screenshot below shows the equipment lists available from the Community. The equipment lists can be sorted by manufacturer or by type [instruments, eyepieces, filters, barlows/reducers, observers, cameras].

Equipment Lists in the Community

You can browse these lists and tap Get to retrieve the equipment list you want. The equipment is stored on your device and may be viewed with Equipment.

DSP Mobile: Settings

Deep-Sky Planner Mobile Edition (DSPME) provides a Settings screen for displaying and modifying app-wide settings. At the moment, it contains configuration options for the download and display of Digitized Sky Survey (DSS) images, and it contains your selection of the application's display style.

[Screenshots were produced on a 10" iPad using the RegalBlue or BlackRed (nightvision) style.]

DSS Options

DSPME allows you to download DSS images for the objects in your observing plans. When you download DSS images, the size of the image is automatically selected based on the size of the object in the plan. For objects that do not have a size metric (like stars), a default size value can be set.

DSS Settings: Image Size and Invert Colors

You can also choose to invert the colors of the image when it is displayed. The default is white on black; inverted produces black on white.

DSS image of M 31 shown with inverted colors

DSS image of M 31 shown with normal colors

DSS images are served from 2 different websites. If one is unavailable temporarily, you can choose the other.

App Style

Several styles are provided with DSPME. You can choose the one that suits your taste. The BlackRed (nightvision) style is included to help keep your eyes dark-adapted. This style should be used along with brightness settings for your device screen to yield a useful display in a dark environment.

Plan displayed in BlackRed (nightvision) style

DSP Mobile: Sky Conditions

Deep-Sky Planner Mobile Edition (DSPME) allows you to record the sky conditions when you observe. These conditions - darkness, transparency and seeing - play a role in calculating visibility models for different kinds of objects. The first two metrics are used to determine whether you can see extended object like galaxies, globular clusters and nebulae. The latter is used to predict whether you can split a pair of double stars. Note that these predictions pertain to visual observing, not imaging.

[Note: Screenshot for this post was made on a 7" Android tablet with the Diamond app style.]

Conditions: Darkness, Transparency and Seeing

The various Sky Conditions should be set for each observing session because these metrics change over time. In fact, they change constantly so you may want to change these several times while you observe.

Darkness is entered in magnitudes per square arcsecond  (MPSAS). This value is readily available from Unihedron's Sky Quality Meter. Naked-eye limiting magnitude (NELM) is also shown, and you can use it to estimate MPSAS. Lastly, the Light Pollution Atlas Zone color[1] is displayed for the MPSAS and NELM values These 3 values can be used together to provide an objective assessment of sky darkness to DSPME.

Transparency can be determined objectively from the aerosol optical depth (AOD) at your observing time and place, or you can use the subjective scale. AOD information is available from various services online, including IDEA[2].

Seeing is a well-known metric to double star observers. A value can be entered in a subjective scale which links a description to the Antoniadi and Pickering scales.

These sky conditions are required for some of the visibility models. Once you have entered all the required components (equipment, observer, conditions), you can use the visibility models in DSPME to help predict your observing results.

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[1] The New World Atlas of Artificial Sky Brightness, https://cires.colorado.edu/Artificial-light

[2] IDEA (Infusing satellite Data into Environmental air quality Applications) is a NASA - EPA - NOAA partnership, https://www.star.nesdis.noaa.gov/smcd/spb/aq/ 

DSP Mobile: Observing Equipment

Welcome back from the holidays! Our story continues ...

Your equipment and observer information can be added into Deep-Sky Planner Mobile Edition (DSPME) so that you can review the metrics of your complete setup - total magnification, field of view (for imaging & viewing) etc. The equipment information is also used by the visibility model when it calculates a prediction of whether you can see an object.

[Note: Screenshots for this post were made on a 9.7" iPad tablet with the Regal Blue app style.]

Owners of the Desktop Edition can export their equipment and observer data to files, and transfer them to a cloud service. These files may be imported into DSPME using the Cloud Import feature as described in a previous post.

Import equipment from Cloud

Important:
Entering equipment and observer data directly into DSPME will be available in a future release.

Once equipment data has been transferred to DSPME, use the Equipment feature to select your combination of equipment. Selections are indicated by the checkmark; the summary of the equipment combination is shown in the right pane.

Equipment selections

The selections made in Equipment are used to predict an object's visibility when the plan is opened. The data item Vis Pred shown below is the result of the visibility model calculation. Note that the visibility prediction applies only to visual equipment combinations. No prediction is calculated for imaging combinations.

Visibility Prediction shown in a Plan

Next time, we'll look at the Conditions feature which is also required for the visibility model to predict whether you might see an object.

DSP Mobile: Observing Locations

Any astronomical application must use the observer's location to produce accurate calculations. Deep-Sky Planner Mobile Edition (DSPME) is no different, and it provides 3 ways to set your observing location.

[Note: Screenshots for this post were made on a 9.7" iPad tablet with the Nightvision app style.]

Provided Locations

Over 400 locations ship with DSPME. You can browse the list and choose a location to be your observing location. If you need a location that is not provided in the database, you can add it by importing a file, or you can add one manually.

Import Locations

To import locations, you export locations to a file in Deep-Sky Planner Desktop Edition and store it on a Cloud Service. Next, you import the file using the Import from Cloud feature. The locations file is downloaded to your device and the locations in the file are imported into the app's database. Locations with duplicate site names are not imported.

Import from Cloud: Adding locations by importing

Enter Manually

To add a location to the database manually, use the Locations feature. You can add a New location, Edit an existing one or Delete an existing one.

Add or Edit a new location

If your device has location services (network location or GPS), you can read location information from the sensor and save it to a location.

Use location services - network info or GPS

If you need to revert to the original set of locations that shipped with DSPME, you can Restore Default so that you don't have to uninstall and reinstall the app to get a clean database.

DSP Mobile: Filtering & Sorting Plans

We continue where we left off in the previous post - exploring the plan window. Deep-Sky Planner Mobile Edition allows you to filter and sort an object listing by several criteria. These functions are accessed on the Filters and Sort tabs of the Plan window, respectively.

[Note: Screenshots for this post were made on a 9.7" iPad tablet with the light Wedgewood app style.]

Filtering

Like the Desktop Edition, you can filter the listing of objects in a plan by several criteria. This does not remove the objects from the plan: it simply hides them in the list. The filtering options include magnitude range, size range, altitude and azimuth in the sky, constellation and object type. Note that the latter two options allow you to select multiple items so you can show objects in 3 constellations for example. The screenshot below shows a filter on altitude where an object must be 20 degrees above the horizon or more to be shown in the list.

Filters: Filtering by altitude

Sorting

Many options are included for sorting the list of objects. You can specify sorting on one or more data items, and you can specify ascending or descending sort direction for each. In the attached screenshot, we sort simply by the Best Time to view an object in ascending order.

Sort: Sort by ascending best time to view

Putting it all together

The Messier List plan is shown below with a typical use case for an observer. It shows objects above 20 degrees in the sky and sorted by ascending best time to view. This is accurate for the time and place of observation, so it effectively tells us which object to view next and the best order to view those that follow.

Objects: Object list sorted and filtered

DSP Mobile: Viewing Plans

Once a plan is stored on your device, you can open it and view it. As with Deep-Sky Planner Desktop Edition, you can set a time and place for the plan, and filter and sort the listing by several criteria.

Setting Time and Place

Astronomical calculations require a time and a place to produce accurate results. The Localize tab of the Plan window provides these functions. You can select your location from the database and the date/ time for your observations as shown below. There are several options for calculating special times of day (sunset and so forth) for the location on the chosen date. You may also download images for objects in the plan from Digitized Sky Survey servers.

[Note: Screenshots for this post were taken on a 10" Android tablet with the Charcoal Gray app style.]

Localize: Location, Date/ Time, DSS Images

Viewing Object Data

Once you have the correct location and time set for your observations, you can view the Objects tab to view object information.

Objects: Object selection and detailed information

The Objects tab is where you find the detailed information for each object in a plan. Some of the data is static and stored in the plan file, but some is ephemeral - calculated for the time and place of your observation. This means that data like Altitude and Azimuth are calculated (and refreshed) as you work. Visibility modeling is also available so that you have an assessment of whether you can view the object given your equipment and conditions.

Filtering and Sorting the plan are important features that will be covered in our next post. Stay tuned!

DSP Mobile: Transferring Data

Deep-Sky Planner Mobile Edition (DSPME) allows you to import plans created by Deep-Sky Planner 7 Desktop Edition via a cloud service or from the Deep-Sky Planner Community at knightware.biz. This option does not require the Desktop Edition. This post explores the first option: importing data from the cloud. The latter option will be described in a later post.

Importing from the cloud is intended for users who own both the Mobile and Desktop Editions of Deep-Sky Planner, and who use a cloud service to transfer data between them. Dropbox, Google Drive and OneDrive are currently supported.

A cloud service may be used to transfer more than just observing plans. Equipment lists and locations may also be transferred. Importing data is as simple as logging into the cloud service from DSPME and downloading file(s) to your device.  The screenshot below shows the feature as it appears on a 10" Android tablet.

File Import via Cloud

[Note that Deep-Sky Planner Desktop Edition will be enhanced in a future release to include support for storing plans, equipment lists and location lists to a cloud service from within the application. Until that enhancement is available, you can use a web browser or an app designed for the service to store data on the cloud service.]

Once a file has been downloaded and stored to your device, the app needs no further connection to the Internet for you to use the plan/equipment/location. They appear elsewhere in the application for you to use.

Plans Stored on the Device

 
Using Deep-Sky Planner Desktop Edition to create observing plans and the Mobile Edition at the telescope offers the best of both worlds - the most flexibility and control in creating your observing plans and the convenience of using your mobile device to view accurate data away from your desktop computer.

Coming soon: Deep-Sky Planner Mobile Edition

Knightware is pleased to announce the upcoming release of Deep-Sky Planner Mobile Edition. It is planned for release in Q1 2019 for Android and iOS devices. It is currently targeted at 7 inch and larger tablets with support for phone-sized screens also coming.

The app has been under evaluation since 2014 and in development since late 2017. A few features remain to be developed for the initial release. Once all features have been added there will be a small, focused beta test program.

The app is designed to be used with or without Deep-Sky Planner Desktop Edition (for Windows). Mobile Edition users will have access to the Deep-Sky Planner Plan Library and equipment lists on the Knightware website. Users of the Desktop Edition will be able to create their own observing plans, equipment lists and location lists, and transfer them to the Mobile Edition via cloud storage services.

The screenshots below were acquired on a 9.7" iPad with the app running its blue-green Calypso skin and the red and black Nightvision skin.The app will ship with several additional skins.

Main app window - Calypso skin

Main app window - Nightvision skin

The observing plan window below shows deep-sky objects in the Messier list. The window includes catalog data, ephemeral (calculated) data and visibility modeling. Stars, doubles, variables, planets, asteroids and comets are also supported.

Plan window - Calypso skin

Plan window - Nightvision skin

Please stay tuned for more information about Deep-Sky Planner Mobile Edition in the weeks to come.

Reviving the Blog

for Android & iOS

It's been a very busy year at Knightware. We have been hard at work on new products while maintaining existing ones. Our newest product, DarkZone, was released in April. It is a very simple app for iOS and Android that converts darkness readings among units (MPSAS, NELM, mcdpsm). It's quite handy if you find yourself needing to convert among these units.

Another mobile app is still being developed. We will make a pre-announcement about it on October 12 at the International Astronomy Show (IAS) at Stoneleigh Park, UK. We will have it available for demonstration there so please stop by our stand (#9) for a quick peek. Once we return to the office from the UK, details about the product will appear on this blog. Please stay tuned for these posts.

With that out of the way, I'd like to share some thoughts about astronomy trade shows and IAS in particular. Knighware has attended several astronomy shows over the past 10 years - most often appearing at NEAF in New York, but also appearing at PATS in California and AstroCATS in Ontario, Canada. Common themes at all of these shows have been meeting users of Knightware's software and learning how other astronomers go about viewing and imaging the night sky. While product sales are important at each show, networking with users, manufacturers and media people are all benefits of going on the road.

Attending IAS in the UK has been on the radar for quite a while. The show has had several years now to mature into an important event for the UK and Europe in general. Meeting some of the many Deep-Sky Planner (DSP) and SQM Reader Pro (SQMRP) users from Europe will be rewarding, as will seeing new equipment and meeting new people.

Along with the upcoming product pre-announcement, we will demonstrate both DSP and SQMRP at IAS. Both will be available from the Knightware Online Store, and DSP will be on offer to show attendees at a special discount price.

If you are a DSP or SQMRP user, please come by stand #9 at IAS and introduce yourself. If you are not able to attend, please watch our social media pages for pictures and posts from IAS.

https://www.facebook.com/deepskyplanner

A New Tool for Describing Sky Darkness

Sky darkness is the subject of a lot of research worldwide. Not only are astronomers interested in measuring the darkness (or brightness) of the night time sky, but governments and institutions are too, especially as it effects humans, animals and plants. Surprising results are being published constantly, including an important one for astronomers last year.

A peer reviewed article* (Atlas) was published in 2016 that included a world map of artificial light. The researchers measured sky brightness for most of the world, although they skipped the very high latitudes in both hemispheres. Measurements were made from satellite- and earth-based equipment. The light values reported in the study were reported in micro- and milli-candelas per square meter. You can read about the study at http://cires.colorado.edu/Artificial-light ; the paper is published at http://advances.sciencemag.org/content/2/6/e1600377 

Candelas are a measure of luminance, not the usual unit of measure used by astronomers. We are more familiar with magnitudes per square arc minute (MPSAS) and naked-eye limiting magnitude (NELM). Converting values among these units helps us understand the relationship between the familiar units (MPSAS or NELM) and the Atlas unit (mcd/m2). Further, the color codes used in the Atlas provide a quick, consistent way of assessing sky darkness.

Introducing Zone Calculator

SQM Reader Pro 3 includes Atlas zone color along with SQM reading values in MPSAS and NELM (and Deep-Sky Planner 7 will too, soon). While developing the feature, a testing tool was developed which is now released to the public. The software is called Zone Calculator and it is available for free at http://knightware.biz/sqm/zonecalc.htm

Hopefully this little tool will help astronomers describe the darkness of their sky in a simple, more uniform way.

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*Falchi, F., P. Cinzano, D. Duriscoe, C. C. M. Kyba, C. D. Elvidge, K. Baugh, B. A. Portnov, N. A. Rybnikova, and R. Furgoni. "The New World Atlas of Artificial Night Sky Brightness." Science Advances 2.6 (2016).

Fun with Globulars

Given the time of year, one might wonder why a post about globular cluster observing comes now. There are 2 good reasons. First, it's a good time to plan observing projects that start in a few months. Secondly, I've done a bit of research lately on the Terzan globulars. There is confusion in the astronomical community about the identification of some of these objects. I believe I have this sorted now - results available in the Plan Library. But I digress, slightly...

Globular Cluster M 22 - Photo by Mark Lang

Observing globular clusters can be a very interesting pursuit. If you observe carefully, you'll notice that they all appear just a bit different. Not only in size and star colors, but notably in how many stars you can resolve, and the pattern of concentration. You can also observe globulars in neighboring galaxies.

Deep-Sky Planner provides a number of resources to help. You can search various catalogs in the database, and you can download several plans from the Plan Library that contain specialized lists of globular cluster. Current these include:

• Astro League Globular Clusters
• RASC Globular Clusters
• Palomar Globular Clusters
• Terzan Globular Clusters.

The AL and RASC lists are designed to educate the observer about observing globulars. They provide a nice sampling of objects and helpful information in their respective publications*. Either is a worthwhile project.

The latter two lists are designed for imagers and observers with large telescopes. The data for these lists are taken from the SIMBAD astronomical database and are supplemented with magnitude and color information gathered by W.E. Harris of McMasters University in Canada.

These are small, faint clusters so you will likely want to download and view DSS images of these objects. Although these clusters have been studied for many years, magnitude and color information is missing for many of the objects.

*AL Globular program material: https://www.astroleague.org/al/obsclubs/globular/globular1.html

*RASC Globular program material: Edgar, James S. Observer's Handbook 2017, Toronto: Royal Astronomical Society of Canada, 2016, p312. Print.