Lick Object of 1921

{{Infobox comet

| name = X/1921 P1 (Lick)

| discovery_ref = {{r|HCOB_757}}

| discoverer = William W. Campbell

| discovery_site = Lick Observatory

| discovery_date = 7 August 1921

| observation_arc = 1 day

| orbit_ref = {{r|Sekanina_2016}}

| perihelion = ~0.25 AU

| physical_ref = {{r|Pearce_1921}}

| magnitude = –2.0
{{small|(1921 apparition)}}

}}

The Lick Object of 1921 is an unidentified astronomical object that was observed from the Lick Observatory in August 1921. Although follow-up observations were not successfully conducted, it is hypothesized that this object is highly likely a non-periodic comet.{{r|Sekanina_2016}}

Observational history

William Wallace Campbell reported the sighting of a star-like object about three degrees from the Sun on the evening of 7 August 1921.{{r|Campbell_1921|HCOB_757}} Observers noted that the object was as bright as Venus, reaching an apparent magnitude of –2 at its maximum.{{r|Pearce_1921}} A possibility that it was a nova explosion was ruled out due to its high relative position (about 40 degrees) to the Galactic plane.{{efn|Reported initial position upon discovery was: α {{=}} {{RA|9|22}}, δ {{=}} {{DEC|15.5}}{{r|Campbell_1921}}}}

Zdenek Sekanina and Rainer Kracht published a study in 2016 where they concluded that the Lick object is highly likely a fragment of the same parent body as the comet C/1847 C1 (Hind).{{r|Sekanina_2016}} Their findings suggested that the Lick Object and C/1847 C1 splitted from a parent body sometime during their perihelion on the 7th millennium BC at a relative velocity of ~{{cvt|1.0|–|1.5|m/s|ft/s}}.{{r|Sekanina_2016}}

References

= Notes =

= Citations =

{{Reflist|refs=

{{cite journal

| author1= W. W. Campbell

| title= Observations of an Unidentified Object Seen Near the Sun on Sunday, August 7, 1921

| url= https://www.jstor.org/stable/pdf/40668524.pdf

| journal= Publications of the Astronomical Society of the Pacific

| volume= 33

| issue= 195

| pages= 258–260

| jstor= 40668524

| jstor-access= free }}

{{cite journal

| author1= S. I. Bailey

| title= Bright Object near Sun

| url= http://tamkin2.eps.harvard.edu/IAUCs/HCOB757a.jpg

| journal= Harvard College Observatory Bulletin

| volume= 757

| date= 9 August 1921 }}

{{cite journal

| author1= J. A. Pearce

| title= The Unidentified Bright Object Seen Near the Sun, August 7, 1921

| url= https://ui.adsabs.harvard.edu/link_gateway/1921JRASC..15..364P/ADS_PDF

| journal= Journal of the Royal Astronomical Society of Canada

| year= 1921

| volume= 15

| pages= 364–367

| bibcode= 1921JRASC..15..364P }}

{{cite journal

| author1= Z. Sekanina

| author2= R. Kracht

| title= Pairs and Groups of Genetically Related Long-Period Comets and Probable Identity of the Mysterious Lick Object of 1921

| url= https://iopscience.iop.org/article/10.3847/0004-637X/823/1/2/pdf

| journal= The Astrophysical Journal

| year= 2016

| volume= 823

| issue= 1

| arxiv= 1510.06445

| doi= 10.3847/0004-637X/823/1/2

| doi-access= free }}

}}

Category:Unidentified astronomical objects