Finding Targets
Finding Targets[edit]
The eVscope is a powerful tool to view and image faint celestial objects of all types. A good starting point are the objects in the eVscope App Catalog, but there are tens of thousands of interesting and worthwhile objects not contained in the Catalog. In addition, there are transient objects and phenomenon that are fascinating and often targets of interest for Science Observations.
Aside from terrestrial and solar observations, finding eVscope targets begin with Orientation. The eVscope/App system has no internal hardware to provide precise telescope pointing information. Only after Orientation can the eVscope be automatically pointed to specific sky locations, and then track those locations as the Earth rotates. (Orientation is also required to use the App to point the telescope to a specific relative azimuth and elevation.) Celestial objects are located using their Right Ascension (RA) and Declination (Dec), a celestial coordinate system that is comparable to geolocation using Latitude and Longitude.
The eVscope's ability to use Enhanced Vision to allow viewing of incredibly faint deep-sky objects (DSO) makes these of particular interest. DSOs are a broad category of telescopic night-sky targets other than individual stars and Solar System objects. These include galaxies, star clusters, and nebulae. There are many lists and sources providing descriptions of DSOs and their location in the sky using their RA/Dec. These include:
| Name | # of Objects | Link |
|---|---|---|
| New General Catalog (NGC) | 7840 | http://cdsarc.u-strasbg.fr/viz-bin/VizieR?-meta.foot&-source=VII/1B, http://ngcicproject.observers.org/ |
| Index Catalog (IC) (supplement to NGC) | 5386 | https://ngcicproject.observers.org/legacy/iconline/default.htm |
| Barnard (B) (Dark nebulae) | 369 | https://in-the-sky.org/data/catalogue.php?cat=Barnard&const=1&sort=0&view=0&page=2 |
| Messier (M) | 110 | http://www.seasky.org/astronomy/astronomy-messier.html |
| Caldwell (C) | 109 | https://www.go-astronomy.com/caldwell-objects.htm |
Unistellar Catalog[edit]
Unistellar advertises that the internal eVscope Catalog V2.1 contains "...over 5,000 objects to choose from..." When the App is configured to display the maximum number of objects (no visibility, type, or magnitude filters), counting the objects displayed results in ~4,000 objects. Objects not routinely made visible by the Catalog may be searchable. The objects have eight selectable categories as follows (numbers are approximate):
- Asteroids (1395)
- Comets (66)
- (Star) Clusters (183)
- Galaxies (1304)
- Nebulae (148)
- Planets (including Moons and the Sun) (13)
- Named Stars (287)
- Others (627)
- 614 variable/double stars, named or with Bayer designation beginning with "*"
- 7 supernovae beginning with "SN"
- 7 stars labeled with HIP numbers
- M73 (asterism), M24 (Sag Star Cloud), SpaceX Roadster
When using the Catalog be aware that the objects shown are dependent on the selected filters (if any). If Visible sky area (VSA) is enabled, the objects selected and shown will depend on choices made on the Settings/Visible sky area page. These include the Sky quality, Location, Altitude range, and Azimuth range. The time of day is a factor if VSA is selected, and current time will also be a factor when sorting "By order of appearance" with VSA enabled.
Other Sources[edit]
Planetarium programs and applications are a popular source for finding interesting astronomical objects. They show the location of objects graphically, in a simulation of the sky over a specific place and time. Most have databases that provide data and detailed descriptions of objects. These programs and applications may be installed on computers/devices, or may be Web applications accessed using a Web browser. Most are free or inexpensive, with additional features unlocked through by buying "Pro" versions or through in-app purchases. In handheld devices, planetarium programs may be linked with the device's location, compass, and accelerometers to allow real-time augmented reality visual simulation of the sky. This allows the user to hold the device up and use it as if it were an annotated window in the sky. Popular planetarium programs include: Sky Map (Android), Sky Safari (iOS, Android), and Stellarium (macOS, Windows, Web)