2015 DR₂₁₅ is a stony near-Earth asteroid of the Atira class residing within Earth's orbit. It was discovered on 18 February 2015 by the Pan-STARRS 1 survey at Haleakalā Observatory at Maui, Hawaiʻi.^[1][2] The asteroid has a diameter of about 200 m (660 ft)^[4] and makes close approaches within 0.05 AU (7.5 million km; 4.6 million mi) of Earth, making it a potentially hazardous object.^[3] On 11 March 2022, it made a close approach 0.045 AU (6.7 million km; 4.2 million mi) from Earth,^[3] reaching a peak apparent magnitude of 17 as it streaked across the southern sky.^[1]

Discovery

2015 DR₂₁₅ was discovered on 18 February 2015 by the Pan-STARRS 1 survey at Haleakalā Observatory at Maui, Hawaiʻi.^[2] It was first observed at apparent magnitude 20.7, located in the southern sky 28 degrees below the ecliptic with an angular separation (solar elongation) of 76 degrees from the Sun.^[2] Follow-up observations from the Mauna Kea Observatory and Cerro Tololo Inter-American Observatory commenced, establishing an observation arc of 12 days until its discovery announcement by the Minor Planet Center on 2 March 2015.^[2]

On 5 March 2016, 2015 DR₂₁₅ was recovered by the ESA Optical Ground Station at apparent magnitude 19, at solar elongations below 56 degrees.^[5] It was observed to be about 0.5 degrees away from its predicted positions in March 2016.^[5] The recovery observations significantly reduced the asteroid's orbital uncertainty, bringing its uncertainty parameter down from 9 to 3.^[2][5]

As of 2022^[update], 2015 DR₂₁₅ has been observed for over 7 years, with a well-determined orbit at an uncertainty parameter of 0.^[3]

Classification

2015 DR₂₁₅ is one of a small number of Atira class asteroids that are orbiting entirely within the Earth's orbit.^[6] The taxonomic class of 2015 DR₂₁₅ in the Bus–DeMeo scheme is Sr, indicating a stony composition.^[4]

Numbering and naming

As of 2023, this minor planet has neither been numbered nor named by the Minor Planet Center.