Discovery Of Supernova Research Articles

The history of astronomy in Queensland

In Queensland during the 19th century, there was no group of wealthy amateur astronomers willing to initiate astronomy as a science in its own right. Instead, astronomy was regarded in a purely pragmatic way, as a tool for surveying, time-keeping and meteorology. As a result, no serious steps were ever taken in Queensland to create a government-funded astronomy centre. This century, in contrast to the low profile of professional astronomy, Queensland amateurs have formed vigorous groups, usually under the leadership of dynamic and dedicated individuals who have spent large amounts on privately owned instruments for long-term projects. Individual amateurs have achieved prominence in the fields of flare stars, lunar occultations, supernova discoveries, and asteroidal occultations.

Supernova rates, galaxy emission, and Hubble type

view Abstract Citations (4) References (12) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Supernova Rates, Galaxy Emission, and Hubble Type van den Bergh, Sidney Abstract Supernova discovery frequency is found to correlate with emission-line (Hα+ [NII]) equivalent width, except for the most active galaxies in which some supernovae might be hidden by dust. SNII occur preferentially in active galaxies with emission-line EW>=20 A, whereas SNIa favor less active galaxies with EW<20 A. The intrinsic frequency of supernovae is found to be an order of magnitude higher in Sc galaxies than it is in early type spirals. The relatively high frequency of SNIa in late-type galaxies suggests that not all such objects have old progenitors. Publication: The Astronomical Journal Pub Date: March 1991 DOI: 10.1086/115729 Bibcode: 1991AJ....101..845V Keywords: H Alpha Line; Nitrogen; Spiral Galaxies; Supernovae; Forbidden Transitions; Galactic Evolution; Galactic Structure; Interstellar Matter; Astrophysics; GALAXIES: STELLAR CONTENT; STARS: SUPERNOVAE full text sources ADS | data products SIMBAD (3)

Supernova search charts handbook

This unique atlas contains 248 charts of more than 300 of the brightest galaxies, each specially prepared to facilitate the discovery of supernovae. The comparison of these charts with the field seen in a telescope enables any extragalactic supernova to be spotted immediately. The charts include 345 galaxies printed on translucent paper for use on a light-box, each one carrying an explanation of the constellation in which the galaxy lies, special characteristics of the galaxy, observing instructions, expected maximum brightness for the supernovae in each galaxy, and the reference for the sequence. A handbook accompanies the charts advising on their use, on how to make and record supernova discoveries, and reviewing the present understanding of supernovae. Published for an international market, these charts carry real potential for numerous discoveries of supernovae. Supernova Search Charts are is a must for both serious observers and the growing number of deep sky enthusiasts around the world.

Amateur Astronomers and the IAU Central Bureau for Astronomical Telegrams and Minor Planet Center

Of all the sections of the International Astronomical Union the Central Bureau for Astronomical Telegrams is undoubtedly the one that most concerns amateur astronomers. Just about anybody in the world with at least some familiarity with the sky has the potential to discover (or to think he or she has discovered) a comet or nova. If the object is real and sufficiently bright, it is very probably already known. Somebody has to be the first discoverer of every comet or nova, however, and soon after the IAU was established in 1919 it set up the Central Bureau to receive and to disseminate to the astronomical community news of such discoveries. Discoveries of supernovae in other galaxies, natural satellites of the planets, erupting x-ray sources and transient features on the planets are also dealt with by the Central Bureau, which since 1965 has operated at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts. The Central Bureau handles unusual minor planets in the vicinity of the earth, although the thousand or more ordinary minor planets routinely discovered each year (and with which amateurs are being increasingly involved) are more appropriately the province of the Minor Planet Center, set up by the IAU in 1947 and since 1978 also operated at the Smithsonian Astrophysical Observatory. About one-quarter of the subscribers to the various services of the Central Bureau and/or the Minor Planet Center are individual amateur astronomers or organizations of amateurs.

Observations – Concluding Remarks

I must speak for all the professional astronomers here in saying that I am most impressed by the contributions made at this IAU Colloquium by amateur astronomers. I spoke earlier of the contacts between amateur astronomers and the IAU Central Bureau for Astronomical Telegrams and Minor Planet Center, particularly with regard to discoveries of comets, novae, supernovae and minor planets. But I also spoke of the great importance of follow-up observations and computations. Janet Mattei has quoted Fran Cordoba’s remark that “discoveries belong to those who keep vigil on them”. It is difficult to deny that the routine of follow-up lacks the glamor associated with making a spectacular discovery, but such discoveries are few and far between, and we need to give greater credit to the unsung heroes who go steadily about this work. Even if all the professional astronomers in the world wanted to pursue this routine, there would not be enough of them to monitor everything that needs to be watched. This is precisely where the amateur comes in.

Radial distribution of types I and II supernovae in spiral and elliptical galaxies

From all the extragalactic supernovae registered before March 1979, 147 SN were selected in galaxies with known parameters (type, diameter, axial ratios and position angle); 114 exploded in S-galaxies (30 type I, 19 type II, and 65 undetermined) and 33 exploded in E/SO-galaxies. The surface density distribution of supernovae as a function of the relative distancef from the galactic centre was investigated. In calculating distances, we used the inclination correction, given by McCarthy (1973) for S-galaxies. The influence of selection effects (connected with bright nuclei of galaxies and with angular resolution) on the discovery of supernovae in distant galaxies has been estimated. It appears that the effects mentioned do not cause serious distortion in the radial distribution of supernovae, except in the central region of galaxies atf≤0.1. Type I supernovae (SNI) in S-galaxies are concentrated at the centre with a slight increase of density gradient and, on average, the SNI in S-galaxies and the SNI in E/SO-galaxies have similar distributions. The SNII distribution in S-galaxies exhibits a ring structure with a maximum atf=0.3–0.4. The radial distribution of SNI in S- and E-galaxies supports the view that the fractions of SNI that are formed at the white-dwarf stage (by accretion in binary systems or instability of a hot white dwarf) are not very large.