Arp Peculiar Galaxy (Northern) Observing Program

 Peculiar Galaxy (Northern) Observing Program Coordinator:

Al Lamperti
112 Pebble Beach Drive
Royersford, PA 19468



"When looked at closely enough, every galaxy is peculiar" - Halton Arp

This Astronomical League Observing Program is based on the 338 objects found in the Arp Catalog of Peculiar Galaxies. One hundred of the 338 Arp galaxies must be observed or imaged to qualify for the Program's certificate and pin (if a pin was not already given for the completion of the Southern Arp Observing Program). Please remember, though, before you start this program, that it was developed for advanced amateurs, and may not be suitable for beginners. For observers and astrophotographers, a majority of the 338 galaxies fall in the 12th to 18th magnitude range. However, there are over 100 Arp objects below magnitude 13.5.

We feel that this new Observing Program will challenge even the most serious of amateur astronomers. We sincerely hope that you find this Observing Program rewarding, and we look forward to your completion of the Program.


Halton C. Arp

Halton C. Arp was one of the key actors in the contemporary debate on the origin and evolution of galaxies in the universe. His landmark compilation of peculiar galaxies, the Atlas of Peculiar Galaxies, led him to challenge the fundamental assumption of modern cosmology, that redshift is a uniform indicator of distance. 


Rules and Regulations

To qualify for the Northern Arp Peculiar Galaxy Program Certificate, you need only be a member of the Astronomical League, either through an affiliated club or as a Member-at-Large, and image or observe 100 of the 338 objects in the Arp Peculiar Galaxy Catalog. You may select any 100 objects that you want to image or observe. Since many of the Arp objects are multiple galaxies, only the brightest member of the group needs to be imaged or observed, but it would be preferred if you could image or observe the entire group. For locating the Arp galaxies, it is recommended that you use a good star atlas such as the "Uranometria 2000.0", Volumes I & II published by Willmann-Bell, Inc., Sky & Telescope's Millenium Star Atlas, or a good computer atlas.

Since this is an advanced observing program for light buckets, it is recommended that you use a telescope with an aperture of 12.5 inches or larger, and observe from a dark sky site. To record your observations, you may use log sheets similar to those found in the back of the Astronomical League's manual Observe: A Guide to the Messier Objects. You can order this observing manual through Astronomical League Sales. If you use your own log sheets, they should include: object name, date and time, power, seeing and transparency, type of instrument, your latitude and longitude, and observing notes.


List of Objects

The list is provided in Arp Catalog number order. Because of the size of the catalog (338 objects), only a limited amount of information can be provided. In addition to the Arp number, you are given additional catalog names that the object is known under, and the Right Ascension and Declination of each object (Epoch 2000). For more information, we recommend a good catalog such as the "Deep Sky Field Guide to the Uranometria 2000.0" published by Willmann-Bell, Inc., or a computer catalog (I used The Arizona Database V. 8.0). Finally, for those of you that like to do constellation hopping or would like to plan your program around what is visible in the sky at certain times of the year, we have provided the Arp Peculiar Galaxy Catalog by constellation. I wish all of you the best of luck in this Observing Program.



I and the Astronomical League wish to gratefully acknowledge Dennis Webb of the Johnson Space Center Astronomical Society for his suggestion to create this program, and for the wonderful work that he has put into investigating the list of objects as reflected in this Observing Program.

- John Wagoner


Submitting for Certification

To receive your Northern Arp Peculiar Galaxy Observing Program certificate and  pin, either send COPIES of your images/observations/astrophotos along with your name, mailing address, phone number, email address, and club affiliation to the Observing Program Coordinator, or have them reviewed and approved by an officer of your local astronomy club who should then send an email to the Northern Arp Observing Program Coordinator. If you have already received a pin and certificate for the Southern Arp, you will receive just a certificate for the Northern Arp, as only one pin is awarded.


Arp Peculiar Galaxy Observing Program Coordinator:

Al Lamperti
112 Pebble Beach Drive
Royersford, PA 19468

Upon verification of your submission, your certification will be forwarded either to you or your club's Award's Coordinator, whomever you choose. Each certificate will be numbered and lettered according to how it was acquired, either through CCD imaging, observation, or astrophotography.



Northern Arp Observing Program Object Lists
Northern ARP by ARP # in PDF format
Northern ARP by Right Ascension in PDF format
Northern ARP in Excel format
Northern Arp Peculiar Galaxy Program Appendix B - by Constellation

Other Northern Arp Observing Program Links
More about Halton C. Arp

Find Your Northern Arp Peculiar Galaxy Program Award