Ellen Howell

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Ellen Susanna Howell (born 1961; [1] also published as Ellen S. Bus) is an American astronomer and planetary scientist who studies the composition and structure of asteroids and comets within the Solar System. She is a research professor at the Lunar and Planetary Laboratory of the University of Arizona, and a team member for the OSIRIS-REx sample-and-return space mission. [2]

Contents

Education and career

Howell majored in geophysics at the California Institute of Technology, graduating in 1981. Returning to graduate study, she completed a Ph.D. in planetary sciences at the University of Arizona in 1995. [3]

After postdoctoral research at the Arecibo Observatory from 1995 to 1999, and continuing as a research associate at Arecibo until 2015, she returned to the University of Arizona in 2015 as a senior research scientist. [3]

Research

In 1977, Howell discovered asteroid 3598 Saucier using the Palomar Observatory. She named it after her grandmother, Agnes Elizabeth Saucier. [4] In the same year, Schelte J. Bus, whom she later married, discovered asteroid 2735 Ellen; he named it after her. [5] Howell discovered comet 88P/Howell at Palomar in 1981. [6]

At Arecibo, Howell's research included radar observations of asteroids including triple asteroid (136617) 1994 CC [7] and near-Earth asteroid 2014 HQ124. [8] After her undergraduate discovery of comet 88P/Howell, Howell has also maintained her interests in the observation of comets, including making radar observations of comet 46P/Wirtanen in 2018 [9] using the Arecibo Observatory, one of the last observations from Arecibo before its 2020 collapse. [10]

Her work with OSIRIS-REx has included the discovery of water-related chemical compounds on asteroid 101955 Bennu, the target of the OSIRIS-REx mission. [11]

Related Research Articles

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(450894) <span class="nowrap">2008 BT<sub>18</sub></span>

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OSIRIS-REx is a NASA asteroid-study and sample-return mission. The mission's primary goal is to obtain a sample of at least 60 g (2.1 oz) from 101955 Bennu, a carbonaceous near-Earth asteroid, and return the sample to Earth for a detailed analysis. The material returned is expected to enable scientists to learn more about the formation and evolution of the Solar System, its initial stages of planet formation, and the source of organic compounds that led to the formation of life on Earth.

Michael Julian Drake, regent's professor, was the director of the University of Arizona's Lunar and Planetary Laboratory and head of the Department of Planetary Sciences. He was the principal investigator of the Origins Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) mission of NASA's New Frontiers Program. The OSIRIS-REx mission, launched on September 8, 2016, and scheduled to arrive at Asteroid Bennu in December 2018, is the most ambitious University of Arizona planetary science project to date and will retrieve a sample of the asteroid and return it to Earth. He also made significant contributions to the study of HED meteorites and studied the origin of water in terrestrial planets.

<span class="mw-page-title-main">(7335) 1989 JA</span> Near-Earth asteroid in 2022

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<span class="nowrap">(285263) 1998 QE<sub>2</sub></span> Near-Earth asteroid

(285263) 1998 QE2, provisional designation 1998 QE2, is a dark asteroid and synchronous binary system, classified as near-Earth object and potentially hazardous asteroid of the Amor group, approximately 3 kilometers in diameter. It was discovered on 19 August 1998, by astronomers of the LINEAR program at Lincoln Laboratory's Experimental Test Site near Socorro, New Mexico, in the United States. Its sub-kilometer minor-planet moon was discovered by radar on 30 May 2013.

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<span class="nowrap">2017 YE<sub>5</sub></span> Binary near-Earth asteroid

2017 YE5 is a binary pair of asteroids of approximately equal size and mass, each about 0.9 km (0.56 mi) in diameter. Classified as a near-Earth asteroid and potentially hazardous object of the Apollo group, 2017 YE5 was discovered by amateur astronomer Claudine Rinner at the Oukaïmeden Observatory on 21 December 2017. On 21 June 2018, the pair of asteroids passed within 15.5 lunar distances or approximately 6 million km (3.7 million mi) from Earth. During the close encounter, 2017 YE5 was resolved in high detail by concurrent radar observations by the Arecibo and Green Bank observatories, along with individual observations by the Goldstone Solar System Radar. 2017 YE5 is likely an extinct or dormant comet due to its distant elliptical orbit and dark red surface.

<span class="nowrap">2020 BX<sub>12</sub></span> Binary near-Earth asteroid

2020 BX12 is a sub-kilometer binary asteroid, classified as a near-Earth asteroid and potentially hazardous object of the Apollo group. It was discovered on 27 January 2020 by the Asteroid Terrestrial-impact Last Alert System survey at the Mauna Loa Observatory during its approach to Earth of 0.02915 AU (4.361 million km; 11.34 LD). Radar observations of the asteroid were carried out by the Arecibo Observatory on 4 February 2020, revealing a natural satellite orbiting 360 m (1,180 ft) from the primary body.

Daniella ("Dani") Mendoza DellaGiustina is a Mexican American planetary scientist and academic. She is the principal investigator for NASA's OSIRIS-APEX Mission to asteroid (99942) Apophis, Deputy Principal Investigator of NASA's OSIRIS-REx Asteroid Sample Return Mission, and assistant professor at the University of Arizona's Lunar and Planetary Laboratory.

References

  1. Macho Stadler, Marta (May 3, 2016), "Ellen Howell, astrónoma", Mujeres con Ciencia (in Spanish), University of the Basque Country , retrieved 2023-07-29
  2. "Ellen Howell", Lunar and Planetary Laboratory Faculty, University of Arizona, retrieved 2023-07-29
  3. 1 2 "Curriculum vitae" (PDF), Lunar and Planetary Laboratory, University of Arizona, January 2020, retrieved 2023-07-29
  4. Schmadel, Lutz D. (2015), "Catalogue of Minor Planet Names and Discovery Circumstances Addendum 2012–2014", Dictionary of Minor Planet Names, Springer International Publishing, p. 36, doi:10.1007/978-3-319-17677-2_2
  5. Schmadel, Lutz D. (2023), Dictionary of Minor Planet Names (3rd ed.), Springer, p. 353, ISBN   9783662066157
  6. King, Bob (September 9, 2020), "Stormy times on Jupiter, Comet Howell steps up, and more", Sky & Telescope, retrieved 2023-07-29
  7. Triple asteroid system triples asteroid observers interest, Jet Propulsion Laboratory, August 6, 2009, retrieved 2023-07-29
  8. "'Beast' asteroid looks like a beauty in radar images", NBC News, June 12, 2014, retrieved 2023-07-29
  9. Morton, Erin (December 20, 2018), "UA Researcher Captures Rare Radar Images of Comet 46P/Wirtanen", Lunar and Planetary Laboratory, University of Arizona, retrieved 2023-07-29
  10. Cantwell, Elizabeth R. (November 23, 2020), Lamenting the Loss of the Arecibo Observatory, University of Arizona, retrieved 2023-07-29
  11. Morton, Erin (December 10, 2018), "UA-Led OSIRIS-REx Discovers Water on Asteroid Bennu", Lunar and Planetary Laboratory, University of Arizona, retrieved 2023-07-29