Ninth Planet Research Articles

Is there really a new ninth planet in the solar system?

Is there really a new ninth planet in the solar system?

Periodic mass extinctions and the Planet X model reconsidered

Abstract The 27 Myr period in the fossil extinction record has been confirmed in modern data bases dating back 500 Myr, which is twice the time interval of the original analysis from 30 years ago. The surprising regularity of this period has been used to reject the Nemesis model. A second model based on the Sun's vertical Galactic oscillations has been challenged on the basis of an inconsistency in period and phasing. The third astronomical model originally proposed to explain the periodicity is the Planet X model in which the period is associated with the perihelion precession of the inclined orbit of a trans-Neptunian planet. Recently, and unrelated to mass extinctions, a trans-Neptunian super-Earth planet has been proposed to explain the observation that the inner Oort cloud objects Sedna and 2012VP113 have perihelia that lie near the ecliptic plane. In this Letter, we reconsider the Planet X model in light of the confluence of the modern palaeontological and outer Solar system dynamical evidence.

Close encounter of the ninth kind [News

In a few short weeks, the NASA New Horizons spacecraft will finish a long, lonely trek through the outer solar system and zip past Pluto. It will gather the first close-up views of the erst-while ninth planet and examine, among other things, Pluto's thin atmosphere by measuring sunlight and radio waves that pass through it.

Welcome to the planet that was

On Jul 14, NASA's New Horizons craft will skim within just 13,000 kilometers of Pluto, entering a hitherto-unexplored zone of the solar system. When this probe was launched in Jan 2006, its destination was still the solar system's ninth planet. Pluto was controversially demoted to a dwarf planet later that year, but its allure is undiminished. Above its surface, frosted with exotic ices, is a strange atmosphere that seeps constantly into space, and a complex system of moons, including the giant Charon. Here, Battersby explores why humans' first visit to Pluto could rewrite the solar system's story.

Comments on the Discovery of a Ninth Planet

Comments on the Discovery of a Ninth Planet

Kepler-91b: a planet at the end of its life

The evolution of planetary systems is intimately linked to the evolution of their host star. Our understanding of the whole planetary evolution process is based on the large planet diversity observed so far. To date, only few tens of planets have been discovered orbiting stars ascending the Red Giant Branch. Although several theories have been proposed, the question of how planets die remains open due to the small number statistics. In this work we study the giant star Kepler-91 (KOI-2133) in order to determine the nature of a transiting companion. This system was detected by the Kepler Space Telescope. However, its planetary confirmation is needed. We confirm the planetary nature of the object transiting the star Kepler-91 by deriving a mass of $ M_p=0.88^{+0.17}_{-0.33} ~M_{\rm Jup}$ and a planetary radius of $R_p=1.384^{+0.011}_{-0.054} ~R_{\rm Jup}$. Asteroseismic analysis produces a stellar radius of $R_{\star}=6.30\pm 0.16 ~R_{\odot}$ and a mass of $M_{\star}=1.31\pm 0.10 ~ M_{\odot} $. We find that its eccentric orbit ($e=0.066^{+0.013}_{-0.017}$) is just $1.32^{+0.07}_{-0.22} ~ R_{\star}$ away from the stellar atmosphere at the pericenter. Kepler-91b could be the previous stage of the planet engulfment, recently detected for BD+48 740. Our estimations show that Kepler-91b will be swallowed by its host star in less than 55 Myr. Among the confirmed planets around giant stars, this is the planetary-mass body closest to its host star. At pericenter passage, the star subtends an angle of $48^{\circ}$, covering around 10% of the sky as seen from the planet. The planetary atmosphere seems to be inflated probably due to the high stellar irradiation.

SPICES: spectro-polarimetric imaging and characterization of exoplanetary systems

SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and circumstellar disks in the visible (450 - 900 nm) at a spectral resolution of about 40 using both spectroscopy and polarimetry. By 2020/22, present and near-term instruments will have found several tens of planets that SPICES will be able to observe and study in detail. Equipped with a 1.5 m telescope, SPICES can preferentially access exoplanets located at several AUs (0.5-10 AU) from nearby stars ($<$25 pc) with masses ranging from a few Jupiter masses to Super Earths ($\sim$2 Earth radii, $\sim$10 M$_{\oplus}$) as well as circumstellar disks as faint as a few times the zodiacal light in the Solar System.

Solix Raises Funds, Launches Algae System

Solix Raises Funds, Launches Algae System

BASF, Solix Join For Chemicals From Algae

BASF, Solix Join For Chemicals From Algae

Pluto — An enduringly interesting celestial object

Pluto is a celestial object that had caught the imagination of increasingly ‘sky-aware’ people all around the world, perhaps due to the inspiring story of its discovery by a young amateur astronomer. It was celebrated as the ninth planet of the solar system for decades. A question mark hung over its nomenclature as a planet from the time of the discovery of its moon Charon, when a good estimate of its very small mass in comparison with other planets was obtained. The discovery of UB 313, a body in the outer regions of the solar system that was more massive than Pluto, magnified this question mark and compelled the International Astronomical Union to review the definition of the word ‘Planet’. A new and physical definition was given to this word and Pluto was categorized as a dwarf planet. The beauty of this physical definition of a planet is something that would definitely have been appreciated by Clyde Tombaugh — who once made this beautifully simple statement about Pluto, while its status was being questioned — “It is there, whatever it is”. Yes, whatever it is, Pluto is one celestial object that is somehow very endearing to everyone around the world and is also an object whose studies are compelling certain paradigm shifts in our understanding of the structure and evolution of the solar system.

'Tenth Planet' found to be a whopper

'Tenth Planet' found to be a whopper

Quantitative models for the kinetics of cell-mediated cytotoxicity at the single cell level.

Is there a role for quantitative theory in helping us understand cell mediated cytotoxicity? In many areas of science, but particularly physics and chemistry, theory has played a fundamental, and in some cases an essential, role in advancing knowledge. In physics a primary activity of theorists is to envision and then explore in a quantitative manner alternative constructions for the universe. A theorist might ask how the orbits of the eight closest planets surrounding the sun would change if there were a ninth planet, or how bubble chamber tracks might look if there were a new elementary particle, or how a clock would run if it were in a space ship traveling at 99% the speed of light, or what the diffraction pattern of nucleic acid would be if the molecule were a double helix. By engaging in flights of fantasy and examining in a quantitative manner the consequences of alternative designs of the universe, great progress has been made in the physical sciences. Given such successes, one is tempted to believe that there is a role for similar theoretical activities in cell biology and immunology. Here we demonstrate how a theoretical approach can be used to gain insights into T cell mediated cytotoxicity.

The satellites of Neptune and the origin of Pluto

Pluto and the chaotic satellite system of Neptune may have originated from a single encounter of Neptune with a massive solar system body. A series of numerical experiments has been carried out to try to set limits on the circumstances of such an encounter. These experiments show that orbits very much like those of Pluto, Triton, and Nereid can result from a single close encounter of such a body with Neptune. The implied mass range and encounter velocities limit the source of the encountering body to a former trans-Neptunian planet in the 2- to 5-Earth-mass range.

The comet and minor planet program at Lowell Observatory

The Lowell Observatory has traditionally been involved with the planets, at its inception in 1894 with the bright planet Mars and culminating in 1930 with the discovery of a 15th. magnitude one, Pluto. In the interim and following, many thousands of minor planets and comets have been observed from five separate series of sky surveys and special observing programs.The first program in search of a trans-Neptunian planet, initiated by Percival Lowell, was begun in 1905 and completed in 1907. The entire ecliptic was photographed, using a 5-inch Brashear lens of 35 inches focal length which covered a good usable field of 5 degrees. Many of the 250 plates made in this series were three-hour exposures, in order to reach the 16th. magnitude. The shorter exposures reached the 14th. magnitude. Cramer Iso-Instant and Seed’s 27 plates were used. Each plate pair of this series was laboriously examined by hand magnifier comparing star for star.

The Search for a Planet beyond Neptune

Previous articleNext article No AccessThe Search for a Planet beyond NeptuneMorton GrosserMorton Grosser Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Isis Volume 55, Number 2Jun., 1964 Publication of the History of Science Society Article DOIhttps://doi.org/10.1086/349825 Views: 9Total views on this site Citations: 4Citations are reported from Crossref Copyright 1964 History of Science Society, Inc.PDF download Crossref reports the following articles citing this article:Konstantin Batygin, Fred C. Adams, Michael E. Brown, Juliette C. Becker The planet nine hypothesis, Physics Reports 805 (May 2019): 1–53.https://doi.org/10.1016/j.physrep.2019.01.009Peiliang Xu Measurement-based perturbation theory and differential equation parameter estimation with applications to satellite gravimetry, Communications in Nonlinear Science and Numerical Simulation 59 (Jun 2018): 515–543.https://doi.org/10.1016/j.cnsns.2017.11.021Giuseppe Pelosi, Stefano Selleri Babinet?s Principle in Electromagnetics: Why Does a Slot Radiate Like a Dipole? [Historical Corner], IEEE Antennas and Propagation Magazine 59, no.22 (Apr 2017): 144–148.https://doi.org/10.1109/MAP.2017.2658345Robert P. Multhauf, Bernard S. Finn, Aleida V. H. Cattell, Gertrude B. Calvert, and Diana D. Menkes Ninetieth Critical Bibliography of the History of Science and Its Cultural Influences (To 1 January 1965), Isis 56, no.44 (Oct 2015): 490–657.https://doi.org/10.1086/350074

THE ASTRONOMICAL ROMANCE OF PLUTO

Systematic search begun years ago supplementing Lowell's investigations for TransNeptunian planet has revealed object which since seven weeks has in rate of motion and path consistently conformed to TransNeptunian body at approximate distance he assigned. Fifteenth magnitude. Position March twelve days three hours GMT was 7 seconds of time west from Delta Geminonim, agreeing with Lowell's predicted longitude.

Address on the Award of the Jackson-Gwilt Medal to Mr. Clyde W. Tombaugh for the Discovery of the Trans-Neptunian Planet Pluto

Address on the Award of the Jackson-Gwilt Medal to Mr. Clyde W. Tombaugh for the Discovery of the Trans-Neptunian Planet Pluto

Societies and Academies

Societies and Academies

THE DISCOVERY, AT THE LOWELL OBSERVATORY, OF A BODY THAT MAY BE A TRANS-NEPTUNIAN PLANET

Cambridge, Mass., March 13, 1930 To Lick Observatory : Lowell Observatory telegraphs systematic search begun years ago supplementing Lowell's investigation of trans-Neptunian planet has revealed object which for seven weeks has in rate of motion and path consistently conformed to trans-Neptunian body and approximate distance he assigned. 15th magnitude. Position March 12th, 3h G.M.T. was 7s west from O Geminorum, agreeing with Lowell's predicted longitude. (Signed) Harlow Shapley Director, Harvard College Observatory

Our Astronomical Column

The Trans-Neptunian Planet.—The following observations of position have been received: those of Mar. 12 and 17 were given only to the nearest second of time in R.A.: