arXiv subjects

Ralph Neuhaeuser

Publications and source records attributed to Ralph Neuhaeuser.

At least 19 recordsLinked to original sources

arXiv2020

Novae, supernovae, or something else? -- (Super-)nova highlights from Hoffmann & Vogt are quite certainly comets (AD 668 and 891)

Galactic novae and supernovae can be studied by utilizing historical observations, yielding explosion time, location on sky~etc. Recent publications by Hoffmann & Vogt present CVs, supernova remnants, planetary nebulae etc. as potential counterparts based on their list of historically reported transients from the Classical Chinese text corpus. Since their candidate selection neglects the state-of-the-art (e.g. Stephenson \& Green), and since it includes `broom stars' and `fuzzy stars', i.e. probable comets, we investigate their catalogue in more detail. We discuss here their two highlights, the suggestion of two `broom star' records dated AD 667 and 668 as one historical supernova and of the `guest star' of AD 891 as recurrent nova U Sco. The proposed positional search areas are not justified due to translation and dating problems, source omission, as well as misunderstandings of historical Chinese astronomy and unfounded textual interpretations. All sources together provide strong evidence for comet sightings in both AD 668 and 891 -- e.g., there are no arguments for stationarity. The AD 667 record is a misdated doublet of 668. Our critique pertains more generally to their whole catalogue of `24 most promising events': their speculations on counterparts lack a solid foundation and should not be used in follow-ups.

astro-ph.SR↗

arXiv2019

A nearby recent supernova that ejected the runaway star zeta Oph, the pulsar PSRB1706-16, and 60-Fe found on Earth

The detection of $\sim 1.5-3.2$ Myr old $^{60}$Fe on Earth indicates recent nearby core-collapse supernovae. For supernovae in multiple stars, the primary stars may become neutron stars, while former companions may become unbound and become runaway stars. We wrote software for tracing back the space motion of runaway and neutron stars to young associations of massive stars. We apply it here to the nearby young Scorpius-Centaurus-Lupus groups, all known runaway stars possibly coming from there, and all 400 neutron stars with known transverse velocity. We find kinematic evidence that the runaway $\zeta$ Oph and the radio pulsar PSRB1706-16 were released by a supernova in a binary $1.78 \pm 0.21$ Myr ago at $107 \pm 4$ pc distance (for pulsar radial velocity $260 \pm 43$ km/s); association age and flight time determine the progenitor mass (16-18 M$_{\odot}$), which can constrain supernova nucleosynthesis yields and $^{60}$Fe uptake on Earth. In addition, we notice that the only high-mass X-ray binary in Scorpius-Centaurus-Lupus (1H11255-567 with $\mu^{1}$ and $\mu^{2}$ Cru) may include a neutron star formed in another SN, up to $\sim 1.8$ Myr ago at $89-112$ pc, i.e. also yielding $^{60}$Fe detectable on Earth. Our scenario links $^{60}$Fe found on Earth to one or two individual supernovae in multiple stars.

astro-ph.HE↗

arXiv2016

Tycho Brahe, Abu Mashar, and the comet beyond Venus (ninth century A.D.)

From his observations of the A.D. 1572 super-nova and the A.D. 1577 comet, Tycho Brahe concluded that such transient celestial objects are outside the Earth's atmosphere, and he quoted the 9th century A.D. Persian astrologer and astronomer Abu Mashar: Dixit Albumasar, Cometa supra Venerem visus fuit, i.e. that he had reported much earlier that comets were seen beyond Venus. However, even from a more detailed Latin translation, the observations and logic behind Abu Mashar's conclusion were not understandable. We present here the original Arabic text (MS Ankara, Saib 199) together with our translation and interpretation: Abu Mashar reported that he had observed Venus in (or projected onto) the tail of a comet and concluded that the comet was behind Venus, because he had observed the extinction of Venus due to the cometary tail to be negligible (light of Venus was unimpaired). He then concluded that the comet would be located behind Venus. He also mentioned that others had observed Jupiter and Saturn in cometary tails, so that those comets would even be located beyond those two outer planets - in the sphere of the stars. The dates of the observed close conjunctions were not mentioned; using known orbital elements for a few comets, we found a few close conjunctions between comets and planets from A.D. 770 to 868, but we cannot be sure regarding which conjunctions were reported. While the argument of Abu Mashar is not correct (as cometary tails are optically thin), parts of the conclusion - namely that comets are outside the Earth atmosphere and beyond the moon - is correct. This may have helped Tycho Brahe to come to his revolutionary conclusion.

physics.hist-ph↗

arXiv2016

Interpretation of the historic Yemeni reports of supernova SN 1006: early discovery in mid-April 1006 ?

The recently published Yemeni observing report about SN 1006 from al-Yamani clearly gives AD 1006 Apr $17 \pm 2$ (mid-Rajab 396h) as first observation date. Since this is about 1.5 weeks earlier than the otherwise earliest reports (Apr 28 or 30) as discussed so far, we were motivated to investigate an early sighting in more depth. We searched for additional evidences from other areas like East Asia and Europe. We found that the date given by al-Yamani is fully consistent with other evidence, including: (a) SN 1006 "rose several times half an hour after sunset" (al-Yamani), which is correct for the location of Sana in Yemen for the time around Apr 17, but it would not be correct for late Apr or early May; (b) the date (3rd year, 3rd lunar month, 28th day wuzi, Ichidai Yoki) for an observation of a guest star in Japan is inconsistent (there is no day wuzi in that lunar month), but may be dated to Apr 16 by reading wuwu date rather than a wuzi date; (c) there is observational evidence that SN 1006 was observed in East Asia early or mid April; for the second half of April, a bad weather (early monsoon) period is not unlikely -- there is a lack of night reports; (d) the observer in St. Gallen reported to have seen SN 1006 "for three months", which must have ended at the very latest on AD 1006 Jul 10, given his northern location, so that his observations probably started in April. We conclude that the correctly reported details give quite high confidence in the fully self-consistent report of al-Yamani, so that the early discovery date should be considered seriously.

physics.hist-ph↗

arXiv2016

Sunspot numbers based on historic records in the 1610s - early telescopic observations by Simon Marius and others

Hoyt & Schatten (1998) claim that Simon Marius would have observed the sun from 1617 Jun 7 to 1618 Dec 31 (Gregorian calendar) all days, except three short gaps in 1618, but would never have detected a sunspot -- based on a quotation from Marius in Wolf (1857), but misinterpreted by Hoyt & Schatten. Marius himself specified in early 1619 that "for one and a half year ... rather few or more often no spots could be detected ... which was never observed before" (Marius 1619). The generic statement by Marius can be interpreted such that the active day fraction was below 0.5 (but not zero) from fall 1617 to spring 1619 and that it was 1 before fall 1617 (since August 1611). Hoyt & Schatten cite Zinner (1952), who referred to Zinner (1942), where observing dates by Marius since 1611 are given, but which were not used by Hoyt & Schatten. We present all relevant texts from Marius where he clearly stated that he observed many spots in different form on and since 1611 Aug 3 (Julian) = Aug 13 (Greg.) (on the first day together with Ahasverus Schmidnerus), 14 spots on 1612 May 30 (Julian) = Jun 9 (Greg.), which is consistent with drawings by Galilei and Jungius for that day, the latter is shown here for the first time, at least one spot on 1611 Oct 3 and/or 11 (Julian), i.e. Oct 13 and/or 21 (Greg.), when he changed his sunspot observing technique, he also mentioned that he has drawn sunspots for 1611 Nov 17 (Julian) = Nov 27 (Greg.), in addition to those clearly datable detections, there is evidence in the texts for regular observations. ... Sunspots records by Malapert from 1618 to 1621 show that the last low-latitude spot was seen in Dec 1620, while the first high-latitude spots were noticed in June and Oct 1620, so that the Schwabe cycle turnover (minimum) took place around that time, ...

astro-ph.SR↗

arXiv2016

An Arabic report about supernova SN 1006 by Ibn Sina (Avicenna)

We present here an Arabic report about supernova 1006 (SN 1006) written by the famous Persian scholar Ibn Sina (Lat. Avicenna, AD 980-1037), which was not discussed in astronomical literature before. The short observational report about a new star is part of Ibn Sina's book called al-Shifa', a work about philosophy including physics, astronomy, and meteorology. We present the Arabic text and our English translation. After a detailed discussion of the dating of the observation, we show that the text specifies that the transient celestial object was stationary and/or tail-less ("a star among the stars"), that it "remained for close to three months getting fainter and fainter until it disappeared", that it "threw out sparks", i.e. it was scintillating and very bright, and that the color changed with time. The information content is consistent with the other Arabic and non-Arabic reports about SN 1006. Hence, it is quite clear that Ibn Sina refers to SN 1006 in his report, given as an example for transient celestial objects in a discussion of Aristotle's "Meteorology". Given the wording and the description, e.g. for the color evolution, this report is independent from other reports known so far.

astro-ph.SR↗

arXiv2015

Presumable European aurorae in the mid AD 770s were halo displays

The interpretation of the strong 14-C variation around AD 775 as one (or several) solar super-flare(s) by, e.g., Usoskin et al. (2013) is based on alleged aurora sightings in the mid AD 770s in Europe: A "red cross/crucifix" in AD 773/4/6 from the Anglo-Saxon Chronicle, "inflamed shields" in AD 776 (both listed in the aurora catalogue of Link 1962), and "riders on white horses" in AD 773 (newly proposed as aurora in Usoskin et al. 2013), the two latter from the Royal Frankish Annals. We discuss the reports about these three sightings in detail here. We can show that all three were halo displays: The "red cross" or "crucifix" is formed by the horizontal arc and a vertical pillar of light (either with the Sun during sunset or with the moon after sunset); the "inflamed shields" and the "riders on white horses" were both two mock suns, especially the latter narrated in form of a Christian adaptation of the antique dioscuri motive. While the latter event took place early in AD 774 (dated AD 773 in Usoskin et al. 2013), the two other sightings have to be dated AD 776, i.e. anyway too late for being in connection with a 14-C rise that started before AD 775. We also sketch the ideological background of those sightings and there were many similar reports throughout that time. In addition, we present a small drawing of a lunar halo display with horizontal arc and vertical pillar forming a cross for shortly later, namely AD 806 June 4, the night of full moon, also from the Anglo-Saxon Chronicle; we also show historic drawings of solar and lunar halo crosses from G. Kirch and Helevius and a modern photograph.

physics.hist-ph↗

arXiv2015

Variations of 14-C around AD 775 and AD 1795 - due to solar activity

The motivation for our study is the disputed cause for the strong variation of 14-C around AD 775. Our method is to compare the 14-C variation around AD 775 with other periods of strong variability. Our results are: (a) We see three periods, where 14-C varied over 200 yr in a special way showing a certain pattern of strong secular variation: after a Grand Minimum with strongly increasing 14-C, there is a series of strong short-term drop(s), rise(s), and again drop(s) within 60 yr, ending up to 200 yr after the start of the Grand Minimum. These three periods include the strong rises around BC 671, AD 775, and AD 1795. (b) We show with several solar activity proxies (radioisotopes, sunspots, and aurorae) for the AD 770s and 1790s that such intense rapid 14-C increases can be explained by strong rapid decreases in solar activity and, hence, wind, so that the decrease in solar modulation potential leads to an increase in radioisotope production. (c) The strong rises around AD 775 and 1795 are due to three effects, (i) very strong activity in the previous cycles (i.e. very low 14-C level), (ii) the declining phase of a very strong Schwabe cycle, and (iii) a phase of very weak activity after the strong 14-C rise -- very short and/or weak cycle(s) like the suddenly starting Dalton minimum. (d) Furthermore, we can show that the strong change at AD 1795 happened after a pair of two packages of four Schwabe cycles with certain hemispheric leadership (each package consists of two Gnevyshev-Ohl pairs, respectively two Hale-Babcock pairs). We show with several additional arguments that the rise around AD 775 was not that special. ...

astro-ph.SR↗

arXiv2015

A review of East Asian reports of aurorae and comets circa AD 775

Given that a strong 14C variation in AD 775 has recently been suggested to be due to the largest solar flare ever recorded in history, it is relevant to investigate whether celestial events observed around that time may have been aurorae, possibly even very strong aurorae, or otherwise related to the 14C variation (e.g. a suggested comet impact with Earth's atmosphere). We critically review several celestial observations from AD 757 to the end of the 770s, most of which were previously considered to be true, and in some cases, strong aurorae; we discuss in detail the East Asian records and their wording. We conclude that probably none among the events after AD 770 was actually an aurora, including the event in AD 776 Jan, which was misdated for AD 774 or 775; the observed white qi phenomenon that happened "above the moon" in the south-east was most probably a halo effect near the full moon - too late in any case to be related to the 14C variation in AD 774/5. There is another report of a similar (or identical) white qi phenomenon "above the moon", reported just before a comet observation and dated to AD 776 Jan; the reported comet observed by the Chinese was misdated to AD 776, but actually sighted in AD 767. Our critical review of East Asian reports of aurorae circa AD 775 shows some very likely true Chinese auroral displays observed and reported for AD 762; there were also several events prior to AD 771 that may have been aurorae but are questionable.

physics.hist-ph↗

arXiv2015

Supernova SN 1006 in two historic Yemeni reports

We present two Arabic texts of historic observations of supernova SN 1006 from Yemen as reported by al-Yamani and Ibn al-Dayba (14th to 16th century AD). An English translation of the report by the latter was given before (Stephenson & Green 2002), but the original Arabic text was not yet published. In addition, we present for the first time the earlier report, also from Yemen, namely by al-Yamani in its original Arabic and with our English translation. It is quite obvious that the report by Ibn al-Dayba is based on the report by al-Yamani (or a common source), but the earlier report by al-Yamani is more detailed and in better (Arabic) language. We discuss in detail the dating of these observations. The most striking difference to other reports about SN 1006 is the apparent early discovery in Yemen in the evening of 15th of Rajab of the year 396h (i.e. AD 1006 Apr 17 \pm 2 on the Julian calendar), as reported by both al-Yamani and Ibn al-Dayba. i.e. about 1.5 weeks earlier than the otherwise earliest known reports. We also briefly discuss other information from the Yemeni reports on brightness, light curve, duration of visibility, location, stationarity, and color.

physics.hist-ph↗

arXiv2015

Newly found sunspot observations by Peter Becker from Rostock for 1708, 1709, and 1710

We present a few newly found old sunspot observations from the years AD 1708, 1709, and 1710, which were obtained by Peter Becker from Rostock, Germany. For 1709, Becker gave a detailed drawing: he observed a sunspot group made up of two spots on Jan 5, 6, and 7, and just one of the two spots was observed on Jan 8 and 9. We present his drawing and his explanatory text. We can measure the latitude and longitude of these two spots and estimate their sizes for all five days. While the spots and groups in 1708 and the spot on four of the five days in January 1709 were known before from other observers (e.g. Hoyt & Schatten 1998), the location of the spots in early January 1709 were not known before, so that they can now be considered in reconstructed butterfly diagrams. The sunspots detected by Becker on 1709 Jan 5 and 1710 Sep 10 were not known before at all, as the only observer known for those two dates, La Hire, did not detect that spot (group). We estimate new group sunspot numbers for the relevant days, months, and years. The time around 1708--1710 is important, because it documents the recovery of solar activity towards the end of the Maunder Grand Minimum. We also show two new spot observations from G. Kirch for 1708 Sep 13 \& 14 as described in his letter to Wurzelbaur (dated Berlin AD 1708 Dec 19).

astro-ph.SR↗

arXiv2015

Solar activity around AD 775 from aurorae and radiocarbon

A large variation in 14 C around AD 775 has been considered to be caused by one or more solar super-flares within one year. We critically review all known aurora reports from Europe as well as the Near, Middle, and Far East from AD 731 to 825 and find 39 likely true aurorae plus four more potential aurorae and 24 other reports about halos, meteors, thunderstorms etc., which were previously misinterpreted as aurorae or misdated; we assign probabilities for all events according to five aurora criteria. We find very likely true aurorae in AD 743, 745, 762, 765, 772, 773, 793, 796, 807, and 817. There were two aurorae in the early 770s observed near Amida (now Diyarbakir in Turkey near the Turkish-Syrian border), which were not only red, but also green-yellow - being at a relatively low geo-magnetic latidude, they indicate a relatively strong solar storm. However, it cannot be argued that those aurorae (geo-magnetical latitude 43 to 50 deg, considering five different reconstructions of the geo-magnetic pole) could be connected to one or more solar super-flares causing the 14 C increase around AD 775: There are several reports about low- to mid-latitude aurorae at 32 to 44 deg geo-magnetical latitude in China and Iraq; some of them were likely observed (quasi-)simultaneously in two of three areas (Europe, Byzantium/Arabia, East Asia), one lasted several nights, and some indicate a particulary strong geo-magnetic storm (red colour and dynamics), namely in AD 745, 762, 793, 807, and 817 - always without 14 C peaks. We use 39 likely true aurorae as well as historic reports about sunspots together with the radiocarbon content from tree rings to reconstruct solar activity: From about AD 733 to 823, we see at least nine Schwabe cycles ...

astro-ph.SR↗

arXiv2015

The companion candidate near Fomalhaut - a background neutron star?

The directly detected planetary mass companion candidate close to the young, nearby star Fomalhaut is a subject of intense discussion. While the detection of common proper motion led to the interpretation as Jovian-mass companion, later non-detections in the infrared raised doubts. Recent astrometric measurements indicate a belt crossing or highly eccentric orbit for the object, if a companion, making the planetary interpretation potentially even more problematic. In this study we discuss the possibility of Fomalhaut\,b being a background object with a high proper motion. By analysing the available photometric and astrometric data of the object, we show that they are fully consistent with a neutron star: Neutron stars are faint, hot (blue), and fast moving. Neutron stars with an effective temperature of the whole surface area being 112,000 K to 126,500 K (with small to negligible extinction) at a distance of roughly 11 pc (best fit) would be consistent with all observables, namely with the photometric detections in the optical, with the upper limits in the infrared and X-rays, as well as with the astrometry (consistent with a distances of 11 pc or more and high proper motion as typical for neutron stars) as well as with non-detection of pulsation (not beamed). We consider the probability of finding an unrelated object or even a neutron star nearby and mostly co-aligned in proper motion with Fomalhaut A and come to the conclusion that this is definitely well possible.

astro-ph.SR↗

arXiv2014

A transient event in AD 775 reported by al-Tabari: A bolide - not a nova, supernova, or kilonova

Given that the cause for the strong increase in 14C in AD 774/5 in Japanese and German trees is still a matter of debate (e.g. short Gamma-Ray Burst or solar super-flare), we have searched in Arabic chronicles for reports about unusual transient celestial events. In the History of al-Tabari we found two (almost identical) reports about such an event. The group around caliph al-Mansur observed a transient event while on the way from Baghdad to Mecca on AD 775 Aug 29 - Sep 1 (Julian calendar). A celestial object (kawkab) was seen to fall or set (inqadda), and its trace (atharuhu) was seen for at least tens of minutes (up to 70-90 min) during morning twilight. The reports use the Arabic words kawkab and athar(uhu), which were also used in the known Arabic reports about supernovae SN 1006 and 1054, so that one might consider an interpretation as a nova-like event. The kawkab (celestial object) was observed only during the morning twilight at a brightness of probably between about -3 and 0 mag. Such a brightness and time-scale would be expected for optical kilonovae (at 3 to 9 kpc) in the context of short Gamma-Ray Bursts. There are no similar reports from eastern Asia for this time. However, the short reports are fully consistent with a bolide: The word kawkab can be used for meteor, the verb inqadda normally means "falling down", the word atharuhu can mean "its trace". We therefore prefer the interpretation as bolide. We discuss in detail how to convert the Muslim calendar date to a date in the Julian calendar using first the calculated Islamic calendar and then considering the time when the crescent new moon could be visible at the given location.

physics.hist-ph↗

arXiv2014

The Chinese comet observation in AD 773 January

The strong 14C increase in the year AD 774/5 detected in one German and two Japanese trees was recently suggested to have been caused by an impact of a comet onto Earth and a deposition of large amounts of 14C into the atmosphere (Liu et al. 2014). The authors supported their claim using a report of a historic Chinese observation of a comet ostensibly colliding with Earth's atmosphere in AD 773 January. We show here that the Chinese text presented by those authors is not an original historic text, but that it is comprised of several different sources. Moreover, the translation presented in Liu et al. is misleading and inaccurate. We give the exact Chinese wordings and our English translations. According to the original sources, the Chinese observed a comet in mid January 773, but they report neither a collision nor a large coma, just a long tail. Also, there is no report in any of the source texts about "dust rain in the daytime" as claimed by Liu et al. (2014), but simply a normal dust storm. Ho (1962) reports sightings of this comet in China on AD 773 Jan 15 and/or 17 and in Japan on AD 773 Jan 20 (Ho 1962). At the relevant historic time, the Chinese held that comets were produced within the Earth's atmosphere, so that it would have been impossible for them to report a "collision" of a comet with Earth's atmosphere. The translation and conclusions made by Liu et al. (2014) are not supported by the historical record. Therefore, postulating a sudden increase in 14C in corals off the Chinese coast precisely in mid January 773 (Liu et al. 2014) is not justified given just the 230Th dating for AD 783 \pm 14.

physics.hist-ph↗

arXiv2014

A solar super-flare as cause for the 14C variation in AD 774/5 ?

We present further considerations regarding the strong 14C variation in AD 774/5. For its cause, either a solar super-flare or a short Gamma-Ray Burst were suggested. We show that all kinds of stellar or neutron star flares would be too weak for the observed energy input at Earth in AD 774/5. Even though Maehara et al. (2012) present two super-flares with 10e35 erg of presumably solar-type stars, we would like to caution: These two stars are poorly studied and may well be close binaries, and/or having a M-type dwarf companion, and/or may be much younger and/or much more magnetic than the Sun - in any such case, they might not be true solar analog stars. From the frequency of large stellar flares averaged over all stellar activity phases (maybe obtained only during grand activity maxima), one can derive (a limit of) the probability for a large solar flare at a random time of normal activity: We find the probability for one flare within 3000 years to be possibly as low as 0.3 to 0.008 considering the full 1 sigma error range. Given the energy estimate in Miyake et al. (2012) for the AD 774/5 event, it would need to be \sim 2000 stronger than the Carrington event as solar super-flare. If the AD 774/5 event as solar flare would be beamed (to an angle of only 24 deg), 100 times lower energy would be needed. A new AD 774/5 energy estimate by Usoskin et al. (2013) with a different carbon cycle model, yielding 4 or 6 time lower 14C production, predicts 4-6 times less energy. If both reductions are applied, the AD 774/5 event would need to be only 4 times stronger than the Carrington event in 1859 (if both had similar spectra). However, neither 14C nor 10Be peaks were found around AD 1859. Hence ...

astro-ph.SR↗

arXiv2013

The Neutron Star Born in the Antlia Supernova Remnant

Among all known young nearby neutron stars, we search for the neutron star that was born in the same supernova event that formed the Antlia supernova remnant (SNR). We also look for a runaway star that could have been the former companion to the neutron star (if it exists) and then got ejected due to the same supernova. We find the pulsar PSR J0630-2834 to be the best candidate for a common origin with the Antlia SNR. In that scenario the SNR is ~1.2 Myr old and is presently located at a distance of ~138 pc. We consider the runaway star HIP 47155 a former companion candidate to PSR J0630-2834. The encounter time and place is consistent with both stars being ejected from the Antlia SNR. We measured the radial velocity of HIP 47155 as 32.42 +/- 0.70km/s.

astro-ph.GA↗

arXiv2012

Neutron stars from young nearby associations the origin of RXJ1605.3+3249

Many neutron stars (NSs) and runaway stars apparently come from the same regions on the sky. This suggests that they share the same birth places, namely associations and clusters of young massive stars. To identify NS birth places, we attempt to and NS-runaway pairs that could be former companions that were disrupted in a supernova (SN). The remains of recent (<few Myr) nearby (< 150 pc) SNe should still be identifiable by observing the emission of rare radioisotopes such as 26Al and 60Fe that can also be used as additional indicators to confirm a possible SN event. We investigated the origin of the isolated NS RXJ1605.3+3249 and found that it was probably born ~100 pc far from Earth 0.45 Myr ago in the extended Corona-Australis or Octans associations, or in Sco OB4 ~1 kpc 3.5 Myr ago. A SN in Octans is supported by the identification of one to two possible former companions the runaway stars HIP 68228 and HIP 89394, as well as the appearance of a feature in the gamma ray emission from 26Al decay at the predicted SN place. Both, the progenitor masses estimated by comparison with theoretical 26Al yields as well as derived from the life time of the progenitor star, are found to be ~11MSun.

astro-ph.GA↗