- Open Position: Research Intern06 Aug, 2020
- Recorded Session: Arecibo Observatory Virtual Town Hall30 Jul, 2020
- The Arecibo Observatory congratulates Dr. Martha P. Haynes, recipient of the Janksy Lectureship 2020! 23 Jul, 2020
- AO Adapts: Continued Workshops, Training, and Education06 Jul, 2020
- Annoucing the Arecibo Observatory Town Hall01 Jul, 2020
- AO Features: Former AO Postdoctoral Researcher Kristen Jones30 Jun, 2020
- New AO Lidar Observations of Ca+ in the Mesosphere and Thermosphere29 Jun, 2020
- Breaking Assumptions on the Excitation Temperatures in Molecular Clouds29 Jun, 2020
- Modifying the Earth’s Ionosphere from Arecibo29 Jun, 2020
- AO radar measurements of Jupiter’s Moons29 Jun, 2020
- A New Approach for Understanding the Occurrence Rate of MSTIDs in the Caribbean Nighttime Ionosphere29 Jun, 2020
- Asteroid Visiting Earth’s Neighborhood Brings its Own Face Mask 23 Apr, 2020
- REU Students’ Research & Presentations01 Apr, 2020
- Transforming the Arecibo Observatory into a Classroom31 Mar, 2020
- Arecibo Observatory re-enters VLBI network with 21st-century backend31 Mar, 2020
- JWST Workshop 31 Mar, 2020
Discovery Announcement of Binary System (163693) Atira
Byadmin20 January 2017 Planetary
E. G. Rivera-Valentin, P. A. Taylor, A. Virkki, and B. Aponte-Hernandez report that Arecibo (2380 MHz, 12.6 cm) delay-Doppler radar images obtained on 2017 January 20 and 23 reveal near-Earth asteroid (163693) Atira is a binary system. Visible range extents of the components in images with 150 m/pixel resolution suggest a primary up to 4.8 ± 0.5 km in diameter and a secondary 1.0 ± 0.3 km in diameter. The primary is possibly elongated and very angular in shape. On 2017 January 20, the system was observed near maximum separation in delay (range) suggesting a mutual-orbit scale of at least 5.7 km. On 2017 January 23, the system was observed near maximum separation in Doppler frequency suggesting an orbital period of roughly 16 hrs. A preliminary circular orbit fit finds a (projected) semimajor axis of 6 km and a period of 15.5 hrs.
 |
 |