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Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 a Good Way to Start – Find North
The expression "dog days" refers to the period from July 3 through Aug. 11 when our brightest night star, SIRIUS (aka the dog star), rises in conjunction* with the sun. Conjunction, in astronomy, is defined as the apparent meeting or passing of two celestial bodies. TAAS Fabulous Fifty A program for those new to astronomy Friday Evening, July 20, 2018, 8:00 pm All TAAS and other new and not so new astronomers are welcome. What is the TAAS Fabulous 50 Program? It is a set of 4 meetings spread across a calendar year in which a beginner to astronomy learns to locate 50 of the most prominent night sky objects visible to the naked eye. These include stars, constellations, asterisms, and Messier objects. Methodology 1. Meeting dates for each season in year 2018 Winter Jan 19 Spring Apr 20 Summer Jul 20 Fall Oct 19 2. Locate the brightest and easiest to observe stars and associated constellations 3. Add new prominent constellations for each season Tonight’s Schedule 8:00 pm – We meet inside for a slide presentation overview of the Summer sky. 8:40 pm – View night sky outside The Midnight Sky: Familiar Notes on the Stars and Planets, Edward Durkin, July 15, 1869 A Good Way to Start – Find North Polaris North Star Polaris is about the 50th brightest star. It appears isolated making it easy to identify. Circumpolar Stars Polaris Horizon Line Albuquerque -- 35° N Circumpolar Stars Capella the Goat Star AS THE WORLD TURNS The Circle of Perpetual Apparition for Albuquerque Deneb 1 URSA MINOR 2 3 2 URSA MAJOR & Vega BIG DIPPER 1 3 Draco 4 Camelopardalis 6 4 Deneb 5 CASSIOPEIA 5 6 Cepheus Capella the Goat Star 2 3 1 Draco Ursa Minor Ursa Major 6 Camelopardalis 4 Cassiopeia 5 Cepheus Clock and Calendar A single map of the stars can show the places of the stars at different hours and months of the year in consequence of the earth’s two primary movements: Daily Clock The rotation of the earth on it's own axis amounts to 360 degrees in 24 hours, or 15 degrees per hour (360/24). -
Arxiv:0809.1275V2
How eccentric orbital solutions can hide planetary systems in 2:1 resonant orbits Guillem Anglada-Escud´e1, Mercedes L´opez-Morales1,2, John E. Chambers1 [email protected], [email protected], [email protected] ABSTRACT The Doppler technique measures the reflex radial motion of a star induced by the presence of companions and is the most successful method to detect ex- oplanets. If several planets are present, their signals will appear combined in the radial motion of the star, leading to potential misinterpretations of the data. Specifically, two planets in 2:1 resonant orbits can mimic the signal of a sin- gle planet in an eccentric orbit. We quantify the implications of this statistical degeneracy for a representative sample of the reported single exoplanets with available datasets, finding that 1) around 35% percent of the published eccentric one-planet solutions are statistically indistinguishible from planetary systems in 2:1 orbital resonance, 2) another 40% cannot be statistically distinguished from a circular orbital solution and 3) planets with masses comparable to Earth could be hidden in known orbital solutions of eccentric super-Earths and Neptune mass planets. Subject headings: Exoplanets – Orbital dynamics – Planet detection – Doppler method arXiv:0809.1275v2 [astro-ph] 25 Nov 2009 Introduction Most of the +300 exoplanets found to date have been discovered using the Doppler tech- nique, which measures the reflex motion of the host star induced by the planets (Mayor & Queloz 1995; Marcy & Butler 1996). The diverse characteristics of these exoplanets are somewhat surprising. Many of them are similar in mass to Jupiter, but orbit much closer to their 1Carnegie Institution of Washington, Department of Terrestrial Magnetism, 5241 Broad Branch Rd. -
The Kinematics of Arp 295 in H-Alpha Emission: an Interacting Galaxy
Revista Mexicana de Astronom´ıa y Astrof´ısica, 00, ??–?? () THE KINEMATICS OF ARP 295 IN Hα EMISSION: AN INTERACTING GALAXY WITH HIGHLY ASYMMETRIC ROTATION Nathan Roche,1 Received November 4, 2018; accepted November 4, 2018 RESUMEN El resumen ser´atraducido al espa˜nol por los editores. We investigate Arp 295, a pair of interacting spirals at z = 0.023, using optical spectroscopy, Hα imaging, and Hα velocity mapping with the Manchester Echelle Spectrograph. Scalelengths are rexp =5.24 for Arp 295a and 2.52 kpc for 295b. A much smaller Im galaxy, Arp 295c, is associated with the larger spiral. Arp 295b is asymmetric with the disk more extended eastwards but with the brightest star-formation regions on its western side. The spectrum of Arp 295b shows strong emission lines with [OII]3727 equivalent width 36A.˚ The total Hα luminosities of Arp 295b and Arp 295c are 4.69 × 1041 and 6.76 × 1040 ergs s−1, corresponding to star-formation −1 rates 3.7 and 0.53 M⊙yr . For Arp 295b, we measure the maximum disk rotation velocity as 252.6 ± 9.9 km s−1 and find the rotation curve is very asymmetric. The east (approaching) side has a higher radial velocity than the west with the maximum difference (at r = 5 arcsec) 88 km s−1 or a factor 1.675. ABSTRACT We investigate Arp 295, a pair of interacting spirals at z =0.023, using optical spectroscopy, Hα imaging, and Hα velocity mapping with the Manchester Echelle Spectrograph. Scalelengths are rexp = 5.24 for Arp 295a and 2.52 kpc for 295b. -
September 2020 BRAS Newsletter
A Neowise Comet 2020, photo by Ralf Rohner of Skypointer Photography Monthly Meeting September 14th at 7:00 PM, via Jitsi (Monthly meetings are on 2nd Mondays at Highland Road Park Observatory, temporarily during quarantine at meet.jit.si/BRASMeets). GUEST SPEAKER: NASA Michoud Assembly Facility Director, Robert Champion What's In This Issue? President’s Message Secretary's Summary Business Meeting Minutes Outreach Report Asteroid and Comet News Light Pollution Committee Report Globe at Night Member’s Corner –My Quest For A Dark Place, by Chris Carlton Astro-Photos by BRAS Members Messages from the HRPO REMOTE DISCUSSION Solar Viewing Plus Night Mercurian Elongation Spooky Sensation Great Martian Opposition Observing Notes: Aquila – The Eagle Like this newsletter? See PAST ISSUES online back to 2009 Visit us on Facebook – Baton Rouge Astronomical Society Baton Rouge Astronomical Society Newsletter, Night Visions Page 2 of 27 September 2020 President’s Message Welcome to September. You may have noticed that this newsletter is showing up a little bit later than usual, and it’s for good reason: release of the newsletter will now happen after the monthly business meeting so that we can have a chance to keep everybody up to date on the latest information. Sometimes, this will mean the newsletter shows up a couple of days late. But, the upshot is that you’ll now be able to see what we discussed at the recent business meeting and have time to digest it before our general meeting in case you want to give some feedback. Now that we’re on the new format, business meetings (and the oft neglected Light Pollution Committee Meeting), are going to start being open to all members of the club again by simply joining up in the respective chat rooms the Wednesday before the first Monday of the month—which I encourage people to do, especially if you have some ideas you want to see the club put into action. -
Publications of the Astronomical Society of the Pacific 102: 59-76, January 1990
Publications of the Astronomical Society of the Pacific 102: 59-76, January 1990 THE SPECTRUM OF NGC 7027 CHARLES D. KEYES AND L. H. ALLER Department of Astronomy, University of California, Los Angeles, California 90024 AND W. A. FEIBELMAN Laboratory for Astronomy and Solar Physics, NASA-Goddard Space Flight Center, Greenbelt, Maryland 20771 Received 1989 August 10, ABSTRACT NGC 7027 is the brightest planetary nebula (PN) in the sky despite the fact that it is dimmed by 14 db (i.e., about 3.5 magnitudes) of local and interstellar extinction. It is also one of the intrinsically most dense and luminous of PN, although it may have evolved from a progenitor in the 1.5-5 SKq range. Observations secured with the Hamilton echelle spectrograph at Lick Observatory and with the IUE are analyzed to obtain nebular plasma diagnostics and chemical abundances. Much of the 3 nebular plasma seems to have a density Ne ~ 60,000 cm and temperature Te ~ 14,000 K, although 3 the [Ne iv] and [Ar iv] auroral/nebular line ratios suggest a ~ 54,000 cm and Te ^ 16,000 Κ 3 zone, while [S π] suggests a zone at Ne ^ 30,000 cm" , Te ~ 13,000 K. Nebular models based on currently available theoretical stellar fluxes for hot stars (Τ ~ 180,000 Κ to 200,000 K) predict He π X4686 too strong and [Ne v] too weak. It is suggested that the stellar radiation field is greatly enhanced shortward of 130 A because of a dense non-LTE wind. The chemical composition appears to be that of a "normal" carbon-rich object rather than that of a nitrogen-rich object such as NGC 2440, which presumably had a massive progenitor. -
IAU Division C Working Group on Star Names 2019 Annual Report
IAU Division C Working Group on Star Names 2019 Annual Report Eric Mamajek (chair, USA) WG Members: Juan Antonio Belmote Avilés (Spain), Sze-leung Cheung (Thailand), Beatriz García (Argentina), Steven Gullberg (USA), Duane Hamacher (Australia), Susanne M. Hoffmann (Germany), Alejandro López (Argentina), Javier Mejuto (Honduras), Thierry Montmerle (France), Jay Pasachoff (USA), Ian Ridpath (UK), Clive Ruggles (UK), B.S. Shylaja (India), Robert van Gent (Netherlands), Hitoshi Yamaoka (Japan) WG Associates: Danielle Adams (USA), Yunli Shi (China), Doris Vickers (Austria) WGSN Website: https://www.iau.org/science/scientific_bodies/working_groups/280/ WGSN Email: [email protected] The Working Group on Star Names (WGSN) consists of an international group of astronomers with expertise in stellar astronomy, astronomical history, and cultural astronomy who research and catalog proper names for stars for use by the international astronomical community, and also to aid the recognition and preservation of intangible astronomical heritage. The Terms of Reference and membership for WG Star Names (WGSN) are provided at the IAU website: https://www.iau.org/science/scientific_bodies/working_groups/280/. WGSN was re-proposed to Division C and was approved in April 2019 as a functional WG whose scope extends beyond the normal 3-year cycle of IAU working groups. The WGSN was specifically called out on p. 22 of IAU Strategic Plan 2020-2030: “The IAU serves as the internationally recognised authority for assigning designations to celestial bodies and their surface features. To do so, the IAU has a number of Working Groups on various topics, most notably on the nomenclature of small bodies in the Solar System and planetary systems under Division F and on Star Names under Division C.” WGSN continues its long term activity of researching cultural astronomy literature for star names, and researching etymologies with the goal of adding this information to the WGSN’s online materials. -