David Robert Ciardi | |
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![]() Ciardi at 2009 Kepler Launch | |
Born | 17 July 1969 |
Nationality | American |
Alma mater | University of Wyoming, Boston University |
Known for | Exoplanet science, infrared instrumentation and observations |
Scientific career | |
Fields | Astrophysics |
Institutions | Caltech, University of Florida |
Thesis | Star Formation in the Filamentary Dark Cloud GF-9: a Multi-Wavelength Intra-Cloud Comparative Study (1997) |
Doctoral advisor | Charles E. (Chick) Woodward |
David Robert Ciardi (born 17 July 1969) is an American astronomer. He received a bachelor's degree in physics and astronomy from Boston University in 1991, and a Ph.D. in physics from the University of Wyoming in 1997.
Ciardi has published refereed journal articles across a wide range of topics, including exoplanets, [1] [2] [3] [4] star formation, [5] interstellar dust, [6] molecular clouds, [7] and evolved stars. [8] [9] His observations of Vega using long-baseline interferometry with the Palomar Testbed Interferometer were the first to spatially resolve the debris disk around this star and to show that dust was present within 1 AU of the star - akin to the interplanetary dust in the Solar System that produces the zodiacal light. [10] This work led to the discovery of dust in the inner regions around other stars and leading to the discovery of a gap between the inner dust ring and the outer dust ring in many systems - the existence of which is still not understood. [11] Ciardi is a member of the Kepler Science Team and using data from the Kepler mission, Ciardi has published landmark works on the fundamental nature of stellar variability [12] and the relative sizes of planets in multi-planet systems [1] and has contributed to more than 250 exoplanet discovery papers, including many of the Kepler Mission discoveries and being the principal investigator of the Palomar Transient Factory Orion Transit Survey [13] and co-discoverer of the first transiting planet around a newly formed T Tauri star in the 3-million-year-old star cluster surrounding 25 Orionis. [2]
Ciardi completed his PhD at the University of Wyoming in 1997, and remained in Laramie for another year as a post-doctoral fellow. He left Wyoming to become a post-doc at the University of Florida, ostensibly to work on the Wide Field Infrared Explorer (WIRE) mission. The unfortunate failure of WIRE's main telescope immediately following launch sidetracked that research path; however, Ciardi remained at Florida and became a staff member with the infrared instrumentation group where he worked on an array of infrared instruments, including T-ReCS for the 8m telescope Gemini South and CanariCam for the 10m Gran Telescopio Canarias. In 2002, Ciardi took a staff astronomer position at the NASA Exoplanet Science Institute; he is currently the NExScI Chief Scientist, and is a Member of the Professional Staff at Caltech.
In 2016, Ciardi was awarded the NASA Exceptional Scientific Achievement Medal for his work on Kepler and his contributions to the confirmation of Kepler's exoplanets which have led to the characterization of planets ranging in size from Jupiters to Earths. The NASA Exceptional Scientific Achievement Medal is awarded to individuals for unusually significant scientific contributions toward achievement of aeronautical or space exploration goals. Asteroid 26312 Ciardi was named in his honor. [14] The official naming citation was published by the Minor Planet Center on 18 May 2019 ( M.P.C. 114954). [15] In September 2019, Ciardi, as part of the TESS team, was awarded the NASA Silver Achievement Medal.
The following is the historic path of Ciardi's advisors - otherwise known as his academic lineage - spanning two centuries of scientific achievement.
Scientist | Year of Ph.D. | Institution |
---|---|---|
Charles Woodward | 1987 | University of Rochester |
Judy Pipher | 1971 | Cornell University |
Martin Harwit | 1960 | MIT |
William Allis | 1925 | University of Nancy |
An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of the detection occurred in 1992. A different planet, initially detected in 1988, was confirmed in 2003. As of 1 December 2023, there are 5,550 confirmed exoplanets in 4,089 planetary systems, with 887 systems having more than one planet. The James Webb Space Telescope (JWST) is expected to discover more exoplanets, and also much more about exoplanets, including composition, environmental conditions and potential for life.
HD 210277 is a single star in the equatorial constellation of Aquarius. It has an apparent visual magnitude of 6.54, which makes it a challenge to view with the naked eye, but it is easily visible in binoculars. The star is located at a distance of 69.6 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −20.9 km/s.
Gliese 687, or GJ 687 (Gliese–Jahreiß 687) is a red dwarf in the constellation Draco. This is one of the closest stars to the Sun and lies at an approximate distance of less than 15 light years. Even though it is close by, it has a magnitude of about 9, so it can only be seen through a moderately sized telescope. Gliese 687 has a high proper motion, advancing 1.304 arcseconds per year across the sky. It has a net relative velocity of about 39 km/s. It is known to have a Neptune-mass planet. Old books and articles refer to it as Argelander Oeltzen 17415.
Transit-timing variation is a method for detecting exoplanets by observing variations in the timing of a transit. This provides an extremely sensitive method capable of detecting additional planets in the system with masses potentially as small as that of Earth. In tightly packed planetary systems, the gravitational pull of the planets among themselves causes one planet to accelerate and another planet to decelerate along its orbit. The acceleration causes the orbital period of each planet to change. Detecting this effect by measuring the change is known as transit-timing variations. "Timing variation" asks whether the transit occurs with strict periodicity or if there's a variation.
Kepler-32 is an M-type main sequence star located about 1070 light years from Earth, in the constellation of Cygnus. Discovered in January 2012 by the Kepler spacecraft, it shows a 0.58 ± 0.05 solar mass (M☉), a 0.53 ± 0.04 solar radius (R☉), and temperature of 3900.0 K, making it half the mass and radius of the Sun, two-thirds its temperature and 5% its luminosity.
Kepler-26 is a star in the northern constellation of Lyra. It is located at the celestial coordinates: Right Ascension 18h 59m 45.8407s Declination +46° 33′ 59.438″. With an apparent visual magnitude of 15.5, this star is too faint to be seen with the naked eye.
Kepler-138, also known as KOI-314, is a red dwarf located in the constellation Lyra, 219 light years from Earth. It is located within the field of vision of the Kepler spacecraft, the satellite that NASA's Kepler Mission used to detect planets transiting their stars.
Kepler-296 is a binary star system in the constellation Draco. The primary star appears to be a late K-type main-sequence star, while the secondary is a red dwarf.
Kepler-84 is a Sun-like star 4,700 light-years from the Sun. It is a G-type star. The stellar radius measurement has a large uncertainty of 48% as in 2017, complicating the modelling of the star. The Kepler-84 star has two suspected stellar companions. Four red dwarfs are few arcseconds away and at least one is probably gravitationally bound to Kepler-84. Another is a yellow star of mass 0.855M☉ on projected separations of 0.18±0.05″ or 0.26″.
HD 179070, also known as Kepler-21, is a F-type subgiant star 354 light-years away in the constellation Lyra. A transiting exoplanet was discovered orbiting this star by the Kepler spacecraft. At a magnitude of 8.25 this was the brightest star observed by Kepler to host a validated planet until the discovery of an exoplanet orbiting HD 212657 in 2018.
Kepler-160 is a main-sequence star approximately the width of our Galactic arm away in the constellation Lyra, first studied in detail by the Kepler Mission, a NASA-led operation tasked with discovering terrestrial planets. The star, which is very similar to the Sun in mass and radius, has three confirmed planets and one unconfirmed planet orbiting it.