A Twilight Search for Atiras, Vatiras and Co-orbital Asteroids: Preliminary Results

Abstract

Near-Earth Objects (NEOs) that orbit the Sun on or within Earth's orbit are tricky to detect for Earth-based observers due to their proximity to the Sun in the sky. These small bodies hold clues to the dynamical history of the inner solar system as well as the physical evolution of planetesimals in extreme environments. Populations in this region include the Atira and Vatira asteroids, as well as Venus and Earth co-orbital asteroids. Here we present a twilight search for these small bodies, conducted using the 1.2-m Oschin Schmidt and the Zwicky Transient Facility (ZTF) camera at Palomar Observatory. The ZTF twilight survey operates at solar elongations down to $35^{\circ }$ with limiting magnitude of $r=19.5$. During a total of 40 evening sessions and 62 morning sessions conducted between 2018 November 15 and 2019 June 23, we detected 6 Atiras, including 2 new discoveries 2019 AQ${}_3$ and 2019 LF${}_6$, but no Vatiras or Earth/Venus co-orbital asteroids. NEO population models show that these new discoveries are likely only the tip of the iceberg, with the bulk of the population yet to be found. The population models also suggest that we have only detected 5--$7\%$ of the $H<20$ Atira population over the 7-month survey. Co-orbital asteroids are smaller in diameters and require deeper surveys. A systematic and efficient survey of the near-Sun region will require deeper searches and/or facilities that can operate at small solar elongations.

AJ accepted

References in corpus (12)

• The Zwicky Transient Facility: System Overview, Performance, and First Results
• The Zwicky Transient Facility: Data Processing, Products, and Archive
• The Zwicky Transient Facility: Science Objectives
• The Zwicky Transient Facility: Surveys and Scheduler
• Systematic ranging and late warning asteroid impacts
• Co-orbital Asteroids as the Source of Venus's Zodiacal Dust Ring
• Towards Efficient Detection of Small Near-Earth Asteroids Using the Zwicky Transient Facility (ZTF)
• The Case for a Deep Search for Earth's Trojan Asteroids
• The digest2 NEO Classification Code
• Debris of asteroid disruptions close to the Sun
• Where are the Mini Kreutz-family Comets?
• Understanding the evolution of Atira-class asteroid 2019 AQ3, a major step towards the future discovery of the Vatira population

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