PoS(MULTIF15)021 http://pos.sissa.it/ 1 [email protected] yrs. Historical records areReviewing the checkedsoft X-ray absorption column fordensities the distance to a A is to estimated -7. is A likely apparent of magnitude The Puppis the visible kpc.~1.3 supernovato be including the ´ of Bethlehem´. Combining the proper motions of the northeast moving oxygen-rich filaments (Winkler et al., 1988 [1]) and the southwest moving (Becker et al., 2012supernova [2])explosion sitethe andposition theof agethe of the are determined.filaments The are assumed decelerating non-radially but axi-symmetrically. The age is 1990 ± 150 Copyright owned by the author(s) under the terms of the Creative Commons Creative of by author(s)Copyright the terms the the under owned

Speaker 1  4.0). 4.0 International (CC BY-NC-ND License Attribution-NonCommercial-NoDerivatives XI Multifrequency Behaviour of High Energy Cosmic Sources Workshop Cosmic Sources Behaviour of High Energy Multifrequency XI May25-30 2015 Italy Palermo, Mozartstrasse 8, Vaterstetten, Germany 8, Vaterstetten, Mozartstrasse E-mail: supernova remnant of the ´Star ofBethlehem´ ´Star of remnant the supernova Aschenbach Bernd PR Vaterstetten Age and distance of Puppis A revised - the the revised - A Puppis and of Age distance PoS(MULTIF15)021 Bernd Aschenbach Bernd = 71 ± 12 mas/yr and NS 2 = 3700 ± 300 yrs, i.e., the apparent age of the SNR, according to the 0 ion of the motion, which, traced back to the past, matches the EC of the ORFs, Becker et al., 2012 [2] measured the proper motion of the NS to μ Revisiting the information about the distance of Puppis A with emphasis on the Revisitinglow energy theA information about the distance of Puppis Figure 1 is a composite of the figure 1 of Winkler et al., 1988 [1] including their figure In this paper I combine the measurement data of the oxygen-rich fast-moving filaments Within the remnantWithin oxygen-rich filaments were discovered, quite many of them show high Puppis A is A Puppisthe name of a supernova remnant (SNR) in the southernIt sky. measures ~50´ Introduction concluding that the expansion center is the SN explosion site. The position of the NS is off-set from the EC by 6.2 arcmin towards the southwest, which, dividing distance by results velocity, indicated by the ellipse. Arguing that Arguing the motion of indicatedthe by ORFsthe did ellipse. not decelerate, the time passed since the explosion is t al. et Winkler of analysis the direct caption, and an overlay with straight lines, markers and etfigure Winkler al.of represents an optical plate which labels,shows eleven fast moving, oxygen-rich which I added. The original filaments (ORFs). The footprints of the arrows mark the position of the ORFs and the length of the arrows indicates the distance The ORFs travelled appear tofor approximately 1000 yrs. have emerged from a common position, the expansion center (EC), with a positional uncertainty X-ray absorption column density a distance of 1.3 kpc is indicated. kpc1.3 densityof distance is column a absorption X-ray Age 2.The explosion date of the SN. The model for the motion of the filaments involves their symmetricalnon-radial but axi-symmetrical deceleration, with deceleration parameters typical for SNRs. The age of Puppis A derived in this way Amongis the~2000 candidatesyrs ofwithin unusuala celestialfairly phenomenanarrow suggested timeby interval. Bethlehem´.Star ´The of event of historical records is the Puppis A was derived by Winkler et al., 1988 [1] using the datatreating ofthem theas opticalsome filamentskind and of ´bullets´ released as such at then. since decelerating the time of the explosion and not and the measurement data of the NS to derive a common explosion site and a common proper motions in the range of 90 to 220 Thesemas/yr. filaments are all found in the northeast quadrant and are moving towards the northeast boundary of the remnant [1]. The only of pulse radiating period (NS) with a neutron in X-rays [6], also star SN aleft presumablycore-collapse 112 ms [7]. The proper motion of the NS was measured and is pointing tofairly theclose southwest opposite[2], to the motion of the optical, oxygen-rich filaments. An age estimate of . Based on spectroscopic, mainly optical line measurements, the supernova been classified as of type2005 The [4]).IIb progenitor (Chevalier, was(SN) presumably a star with a has mass of about 25 solar masses (Canizares &1981 Winkler, [5]), which lost a major fraction of exploding.H/He envelope its before 1. in diameter. Its distance, based on HI and CO measurements, is about 2.2 kpc (Reynoso et al., 2003 [3]), its age has been estimated to be about 4450 yrs (Becker et al.,The 2012 [2]). remnant shows radio, infrared, optical and X-ray emission. It is one of the brightest X-ray SNRs in the Puppis A and the ´Star of Bethlehem´ ´Star and the A Puppis PoS(MULTIF15)021 , x ij 35

(1) and x = m = S m x 45 S ~ t = 0.4, t = x y +

with m the 13 m S –

Bernd Aschenbach Bernd 14 = 3700 yrs and m 0 Dec (2000.) = Dec -42°59´10´´. (2000.) t s s 09 m 22 h 35 35 = 11.1´, ) (2) ) c 13 t = S t = NS tan(φ x 3 + μ + 0 is to be replaced by the letter μ.The configuration

t = 6.18´, S y from position´4´. The conditions S 35 c t – μ t – tan(φ) = tan(φ)= m y y /m y μ the individual deleceration parameters, respectively. This implies a y In the following, distances between various positions are denoted by S >. For proper motions v y y.. and m

m y I study the case assuming that the ORFs are decelerating with time. I use a self-similarity μ > and v x ~ t y m and 1990 ± 150 yrs, the site of the SN explosion (´4´) is located at 2.35´ off the present NS position 08 = (2000.) or towards the EC RA along the (´5´) y-axis, largest off-axis angle φ, characterizing x vs. y deceleration, thereby best suited to discriminate between m which are very precisely measured for the positions ´1´, ´2´, ´5´, arcmin exceptuncertainty. Position for´4´ would´3´ be the with´true´ explosionabout site of1 the SN, and filament ´2´ was ´ejected´ under the corrected angle φ The ORF filament ´1´ propagates basically along the y-axis (on-axis), the filament ´2´ has the difference difference between the currently measured velocity v and mean velocity , such that v

: (RA, :Dec) at hand, the position and the proper motion vector of each filament have been checked been vector filament haveeach theproper motion of and athand,the position y m Some evidence for this configuration might be obtained from figure 2, which shows the X- The approach chosen would suggest that the SN exploded in a stratified, close to plane- Figure 2 Figure and x fairly straight northeast boundary of the remnant, towards which also the brightness increases, which in turn increases with the ambient density squared. The normal and the almost straight The straight line marks the y-axis, i.e., the ´explosion axis´. It runs through the NS position and separates the remnant axi-symetrically in two parts and is almost parallel to the normal of the ray image of Puppis A published by Dubner etal.,2013 by [8]. publishedDubner A Puppis of ray image parallel, ambient medium with its normal towardsparallel the northeastto direction whereasthe the expansiony-axis along theand x- andthe z-directions areevolutionary densityin an increasing phase between propagation asymptotic. in the progenitor´s stellar wind and the Sedov r the distance from the explosion center. Of course, m analogy with the expansion of SNRs. Other choices are possible and higher values of m deceleration) suggest a higher age, but within the uncertainty range of the measurements an age of ~2000 yrs within a fairly if narrow interval some is significant deceleratingvery likely, of the ORF´s is applicable. found to be consistent within the measurements uncertainties. consistent within be tothe measurements found The values of the deceleration parameters are close to what is expected from solutions selffor the expansion of similaritySNR.The m in an ambient medium of constant density (m = 2/5).expansion in an ambient medium with a radial density profile declining Theproportional to r m kept. This is equivalent to the expression of equationlargest off-axis angle[2]. and the relatively lowest proper motion measurement uncertainties, m 4/7 derived from figure 1. With these estimates of the position of the explosion center, the age, m against the respective measurements delivered by Winkler et. al in their figures 1and 2 and are Puppis A and the ´Star of Bethlehem´ ´Star and the A Puppis Maintaining the symmetry with respect to the y-axis the distance along the x-axis needs to be PoS(MULTIF15)021 . -2 21 -2 cm At its cm 21 21 = 3.3·10 H -ways, show -ways,show a = 1.5·10 = 1.6·10 Bernd Aschenbach Bernd H H

across the remnant with the highest column H 5 (left): Same as Fig. 2 in galactic coordinates, galactic plane plane SameFig.the coordinates,towards top. (left):2 as in galactic galactic (right): Neutral hydrogen column density (NH) integrated up to the systemic column (NH) integrated densityhydrogen Neutral (right): A distance to Puppis A of 2.2 kpc has been derived from studies of HI and CO Puppis A, projected Puppis isonSNR, theveryas closesky, shown toin theVela figure 4a.

Figure 3a demonstrates that the ´explosion axis´ is approximately parallel to the normal of

([10, 11]). Outside of this lane the X-ray absorption column density N -2 with blue being the hardest. As stretchingcan across the bePuppis A remnant (darkseen blue). It thereis coincident iswith the neutralan hydrogen NH lane shown ineven figure 3b; it is a regionharder of higher X-ray absorption with aspectrum total N for a lane cm (Aschenbach, 1993 [10]), later confirmed by Hwang et al., 2008 [11]) with N suggested that this lane, possibly a foreground effect,lane, ofright this left- and Measurements absorption outside the X-ray [10]). 1993 causes extra absorption (Aschenbach, a asindicator. distance therefore more representative column and lowerdensity are significantly showsnorthwest up.cornerA The Puppiscolours represent the hardness of the X-ray spectrum, distributions [3]. In contrast, the show a systematic A et al., 2000 [9]). Spatially resolved spectra X-ray across Puppis (Woermann study of OH molecules suggestsvariation of the X-ray absorbing column density aN distance of 1.3 kpc density in the blue lane of figure 3a, which coincides with the lane of NH excess, figure 3b. I to the systemic velocity of Puppis A [8]. Two componentstowards the galacticare plane and dropvisible. along the direction below the NSNH position (galactic south). values increase The second NH component is the vertical band which coincides with the blue lane of figure 3a, A. Puppisofboundary thegalactic beyondsouthern even 3.The Distance velocity of Puppis A. Note the lower NH away from the galactic plane (towards plane from (towards the the galactic Note away A. the NH lower Puppis velocity of al.,2013 (Dubner [8]). thevertical et outside lane bottom) and the galactic plane. Figure 3b shows the distribution of the neutral hydrogen (NH) integrated up Figure 3a Figure 3b Figure remnant in galactic coordinates, which is shown in figure coordinates,3. is shown in figure remnant which in galactic Puppis A and the ´Star of Bethlehem´ ´Star and the A Puppis delineation of the remnant´s northeast boundary might get some meaning when viewing the PoS(MULTIF15)021 ~ 2.8, and v Bernd Aschenbach Bernd Puppis A is 1.3 kpc, . , the distance to -2 distribution across the SNR, which distribution across theVela , contour lines and grey scale, linesscale, of grey and contour , H cm H 21 for theSN A Puppisare estimated as follows; v 6 value outside the blue lane is a representative

H = 1.5·10 (Lu & Aschenbach, 2000 [12]). 2000 Aschenbach, (Lu & Puppis -2 , H cm 21 . Scaling with the distance SNR,to whichthe Vela is fairly well known, i.e. -2 cm 20 (left): X-ray colour image of the Vela SNR including Puppis A at the upper right right attheupper A includingPuppisSNR Vela the ofcolour image X-ray (left): (right): X-ray absorbing column density N density absorbing X-raycolumn (right): = 3·10 Interestingly, Interestingly, the lids of wooden sarcophagi of Pharaohs of ancient Egypt are decorated Based on the distance of 1.3 kpc and using the light curve of the SN prototype IIb, corner (dark blue) with the almost black lane crossing. blue) thealmost withblack lane (dark corner

Lu & Aschenbach, 2000 [12] Lu have & mapped the N Vela , H with with inscriptions They thewhichwere basis represent star attemptsfor catalogues. to a construct unobservable with the unaided eye. With the progenitor identified it turns out SN1993J identified turns thatout starstheprogenitor it With with the unaided unobservable eye. and SN1987A as well brightened in the visible Thusprogenitors. the bandSNprogenitor ofwould A thehave beenPuppis as bright as m by ~10 magnitudes compared to their it may have been well known to the contemporaries and before, and the SN new star star. knownthan a rather somea flaring asof regarded might have been SN1993J in M81, apparent visual magnitudes m peak: -7.2, first minimum at day 5: -4.9, secondary maximum at day 17: -6.6, at four months: -4.6, at one year: -2.2, at 2.5 years: 2.8, at 4 years: 5, after which the star started to get As a side effect, with d = 1.3 kpc, the space velocity of theNS A Puppis is 440 ± 75 km/s, object. doesbut isstill hypervelocity invoke which not a high, 4.The Supernova Figure 4a Figure 4b Figure right.Grey attheupperscale black-encircled white patch as A Puppis with SNR Vela the of is at the in units 10 bottom

which is in agreement with the OH measurements. theOH with isin measurements. agreement which measure for the distance. for measure is shown in figure 4b. In the area closest to Puppis A at the N outermost edge of the SNRVela 250 pc (Cha et al., 1999 [13]) and N Puppis A and the ´Star of Bethlehem´ ´Star and the A Puppis In the following I assume that the latter N PoS(MULTIF15)021

= 2.4), which v Bernd Aschenbach Bernd south the latter of which Kinematics of in oxygen-rich filaments , 141. = 4.44, which is fairly faint to have v 755 ApJ ApJ Proper Motion of Central the RX Compact Object Proper Supernova and the Remnants Medium´, Interstellar ~ 2.8. It is located at almost the same right v 7 101, IAU Colloq. , 1-9, in the Bible´s NewAccording Testament. to historians the 2 he epoch 1990±150 yrs back in time, i.e., ~150 BC to ~150 AD, Chinesehistorical AD, BCtime, ~150 in backi.e., to ~150 yrs 1990±150epoch he , in proceedings of , in of proceedings At last, the SNR RX J0852-4622 (Aschenbach, 2013 [15]) might be another supernova There have been many prophesies, myths and legends concerning ´The Star´, which I have Another candidate for a SN in this time period is ´The Star of Bethlehem´, which is known t For J0822-4300 in the Supernova Remnant Puppis A, Supernova the Remnant J0822-4300 in Puppis Puppis A Puppis 65. Landecker, L. T. Roger R. &eds. S. W. Becker, T. Prinz, P. F. Winkler, R. Petre 2012, R. Winkler, F. P. Prinz, T. Becker, W. P. F. Winkler, J. H. Tuttle, R. P. Kirshner, M. J. Irwin 1988, M. J. Irwin Kirshner, P. R. Tuttle, J. H. Winkler, F. P. [2] [1] References estimated to be between 1200 and 2200 yrs (Katsuda et adiabatical., 2008 evolutionary[16]), if the phase. SNR is That in its timeAllen evolutionary etphase al.,were applied.2015 [17] applied the same analysis method but at span expands to 700 a different tilrim location of the SNR 4300and conclude that the SNR yrsis between 2.4 and 5.1 ifkyr old. 600 800 betweenandyrs. age suggest an etal.,1999 Aschenbach[18] a Early estimates of different Sirius, the brightest star in the sky, to the center of Puppisseparation through anotherA, bright star in passesCanis Majoris with theatAludra name (m half of their angular ´Virginity´. or and´Virgin´ means Arabic is remnant candidate for ´The Star of Bethlehem´. The kinematic age of the SNR has been southern sky could have been visible from geographical latitudes like that of Bethlehem from to May. October no right to comment. This paper simply suggests a SN/SNR candidate for ´The As Star´. far as the myths are concerned, I cannot resist mentioning a curious observation.A straight line from from the gospel of Matthew isThis compatible AD. time of the ´The Star´appearance may be 7-4 BC or up later to about 110 with the age derived in this work forA. TherePuppis is to my knowledge no information about the within which ´The Star´ appeared. The Puppis A SN lightning up deep in the counterpart within <20°, which is significantly larger than the typical angular uncertainties of the Chinese record data with respect to events having been identified asAn SN.interesting case however is the event of AD107 which is the most southerly event reported. The position is not well known and may be imprecise by more than one hour in right ascension, degreesand furthera south couplewould bringof it close to PuppisA. Further study of the historical records the situation. may clear significantly higher brightness of estimated m ascension with a difference of ~15 min, and a position 6.5° . setting is concerned the andfar timing rising as the star´s asof difference basically no makes further records show some time-relevant entries but their celestial coordinates do not have any SNR been created around 1450 BC. Leitz, 1995 [14] has published a identification of each of identification the stars of a each 1995 Leitz,of published 1450 around[14] has BC. created been which appeared to been used for this purpose. In the context of this work one identification is interesting, it is the star q Puppis with a magnitudeserved m as a calendar ´guide´ star, stressed by the fact that Instead, isI missingpropose thein progenitorPtolemy´s of Almagest. the PuppisA SN to be the star in question because of its Puppis A and the ´Star of Bethlehem´ ´Star and the A Puppis calendar, in particular the so-called ´Ramesside decanal clocks´, which are suggested to have PoS(MULTIF15)021 , , , , 619 13 , ApJ ApJ , 317 , L43. , L43. 465 , ApJ ApJ , , AdSpR AdSpR , , 671. , 141. , ApJ ApJ , , MNRAS Bernd Aschenbach Bernd 345 396 , Nature , MNRAS , 997. , L35. 350 695 The most complete and detailed X-ray , A&A A&A , , ApJ ApJ , Observations of the neutral hydrogen of neutral hydrogen the Observations , 12. Constraints of age, distance and progenitor of the of age, and progenitor distance Constraints Hydroxyl lines towards Puppis A Puppis lines towards Hydroxyl 798 , L35. , L35. On the Expansion Rate, Age, and DistanceAge, of the Rate, Expansion the On 8 The Distance to the to VELA the The Distance A Central Stellar Remnant in Puppis A Remnant Puppis Central in Stellar A 278 X-Ray-emitting Ejecta in Puppis A Observed with with Observed A X-Ray-emitting Ejecta Puppis in , ApJ ApJ , ´, Orientalia Lovaniensia Alalecta, Peters Publisher, Alalecta, Peters Publisher, Orientalia´, Lovaniensia The Slow Rim of the X-Ray of Expansion Northwestern the , ApJ ApJ , Evidence for elemental enrichment of Puppis A by a Type II a Type by A for PuppisEvidence elemental enrichment of Discovery of a 112 ms X-Ray in Puppis A: FurtherA: in Puppis X-Ray ms Pulsar ofDiscovery a 112 555, 9. Spatially resolved X-ray spectroscopy of the Vela supernova remnant supernova of Vela the X-ray spectroscopy resolved Spatially A&A , Young Core-Collapse Supernova Remnants and Their Supernova Supernovae Remnants Core-Collapse Young Discovery remnant nearby of a young supernova X-ray emission from supernova remnants observed with ROSAT supernova remnants X-ray from emission , 33. , 378. 246 Altägyptische Sternuhren Altägyptische 676 , ApJ ApJ , , 1083. , ApJ ApJ , 362 , L25. supernova remnant RX J0852.0-4622/GRO J0852-4642 remnant supernova Supernova RX J0852.0-4622 Remnant Jr.) Supernova G266.2-1.2 Remnant (Vela 515 90-6831-669-9. ISN Belgium, Suzaku A&A 421. 45. Evidence of Neutron Stars Weakly Magnetized at Birth Magnetized Stars Weakly ofEvidence Neutron A ofview SNR the Puppis 839. supernova surrounding the radio-quiet neutron star RX J0822-4300 in Puppis A A in Puppis star J0822-4300 RX neutron radio-quiet the surrounding S. Katsuda, H. Tsunemi, K. Mori 2008, Mori K. Tsunemi, S. Katsuda, H. et DeLaney 2015, al. T. K.Allen, Chow, G. E. 1999, Schönfelder V. Iyudin, A. Aschenbach, B. C. 1995, ´ Leitz Aschenbach 1998, B. U. Hwang, R. Petre, K. A. 2008, Flanagan U. R. Petre, Hwang, K. Aschenbach 2000, B. Lu, F. 1999, C.A. Danks A. R. Cha, K. Sembach, N. B. Woermann, M. J. Gaylard, R. M. J. Gaylard, Otrupcek 2000, Woermann, B. Aschenbach 1993, B. R. Petre, C. M. Becker, P. F. Winkler 1996, Winkler F. P. C. R. M. Becker, Petre, Halpern 2009, P. J. Gotthelf, V. E. al. et Rodriguez-Pascual, 2013, P. Loiseau, N. G. Dubner, R. A. 2005, Chevalier R. 1981, Winkler F. C. R. P. Canizares, E. M. Reynoso, A. J. Green, S. J. Green, Johnston, 2003, al. A. et E. M. Reynoso, [9] [6] [7] [8] [4] [5] [3] [11] [16] [17] [18] [14] [15] [12] [13] [10] Puppis A and the ´Star of Bethlehem´ ´Star and the A Puppis