Comet Arend-Roland (C/1956 R1)

Discovered by:        Sylvain Arend and Georges Roland
Discovery date:       November 8, 1956            
Peak magnitude:     -0.5
Aphelion:                N/A
Perihelion:               0.316 AU (47.27 million kilometres or 29.37 million miles)
Semi-major axis:     45,000 AU (6730 billion kilometres or 4180 billion miles)
Eccentricity:           1.00024
Orbital period:         N/A
Inclination:              119.9 degrees

Last perihelion:        April 8, 1957
Next perihelion:       N/A (ejection from Solar System)

Comet Arend-Roland photographed on April 26, 1957 with the 48-inch Palomar Schmidt telescope (Palomar Observatory).

Discovered on November 8, 1956 by Belgian astronomers Sylvain Arend and Georges Roland from photographic plates taken at the Uccle Observatory (Royal Observatory of Belgium) in Brussels.

The comet was magnitude +10 when discovered exhibiting a prominent central condensation and a short tail.

Perihelion occurred on April 8, 1957. It was well seen from the Northern Hemisphere during April, peaking at magnitude -0.5.

The tail of Arend–Roland reached a length of 15 degrees and for a few days in April a prominent anomalous tail (or antitail) about 5 degrees in length was visible. This remarkable event resulted in a rarely spectacle of a "spiked" comet.

For the first time attempts were made to detect the comet at radio frequencies. However, these efforts were unsuccessful.

This was the one and only appearance of this comet from Earth. With a hyperbolic orbit, Arend–Roland is traveling fast enough to completely escape from the Solar System and therefore will never return to our vicinity.

Comet Arend–Roland was the subject of the very first edition of the BBC's long running astronomy program The Sky at Night on April 24, 1957.