Arecibo Observatory

Scientific User Portal


RECENT POSTS

Arecibo Observatory to Offer New Opportunities for Visiting Scientists

The Arecibo Observatory in Puerto Rico will launch a new series of programs to host junior and senior scientists at the observatory to boost the transfer of science knowledge and train the next generations of observatory users. Read More


Planetary Science AO Colloquium: Dr. Michael Denton

The first colloquium of 2020 was held on January 21st and featured a talk describing the Unsolved Problems in Plasmaspheric Physics from Dr. Michael Denton, Research Scientist with the Space Science Institute at Los Alamos in New Mexico. Read More



Astronomy AO Colloquium: Dr. Alain Herique

On January 28th, the AO Colloquium Series featured Dr. Alain Herique of the Institut de Planetologie et d’Astrophysique de Grenoble (IPAG) University Grenoble Alpes in France. Read More


Colloquium   Dr. England visited us Oct 15, 2019
Recently, we had the honor of having Dr. Scott England as our speaker with his talk "EXPLORING THE BOUNDARY BETWEEN EARTH & SPACE WITH ICON". His participation was broadcasted live. View recording here.

Abstract: The near-Earth space environment is far from empty. Occupying the region where astronauts and low-earth-orbiting spacecraft fly is a the last, most tenuous portion of our atmosphere. Sunlight breaks apart the molecules of gas at these altitudes, creating exotic and corrosive species such as atomic oxygen, as well as charged ions and electrons... Read More

Planetary Sciences Arecibo Observatory Radar Tracks Close Flyby of Asteroid 2019 OK

Radar images obtained by the Arecibo Observatory on the 4th and 5th of February revealed that near-Earth asteroid 2020 BX12 is a binary asteroid. The detection of a satellite was made during the first planetary radar observations conducted at the observatory following a month-long shutdown of telescope operations caused by a series of earthquakes striking the southern part of the island of Puerto Rico. The primary asteroid was discovered on the 27th of January by the ATLAS survey on Mauna Loa in Hawaii and fits the definition of a potentially hazardous asteroid (PHA) due to its size and minimum orbit intersection distance (MOID) of 302,000 km (188,000 miles) from the Earth. While this means it could conceivably come closer to the Earth than the Moon, 2020 BX12 poses no danger at this time and is currently receding from Earth. Read More


Planetary Sciences Arecibo Observatory Radar Tracks Close Flyby of Asteroid 2019 OK

On July 24th 2019, an asteroid called 2019 OK passed by the Earth at only 1/5 the distance to the Moon, with a relative velocity of 15 miles per second (~55,000 miles per hour). 2019 OK was discovered by the SONEAR Observatory in Brazil just one day before it zipped past the Earth. It is estimated to be between 50 – 130 meters (165 – 430 ft) in size. Read More



Planetary Sciences A Discovery Announcement of Binary System Near-Earth Asteroid 2016 AZ8

A. K. Virkki, S. E. Marshall, F. C. F. Venditti, L. F. Zambrano Marin, Arecibo Observatory, University of Central Florida, and E. G. Rivera-Valentin, P. A. Taylor, Lunar and Planetary Institute, Universities Space Research Association, report that Arecibo (2380 MHz, 12.6 cm) range-Doppler radar images obtained on 2019 January 4.72 UT reveal near-Earth asteroid 2016 AZ8 is a binary system. Preliminary measurements of visible range extents in radar images with 7.5 m/pixel resolution suggest a rounded primary of diameter 420 ± 60 m and an elongated secondary 180 ± 30 m long. This implies a visual albedo of 4 ± 1% for an absolute magnitude of 21.0. The system was observed near maximum range separation along the line of sight at 420 ± 45 m, which is a lower bound on the mutual-orbit scale due to possible projection effects. Echo bandwidths place upper bounds on the rotation periods of the primary and secondary of 7 and 40 hours, also subject to projection effects. Further observations are encouraged; no more radar observations from Arecibo are possible this apparition. A projected separation comparable to the primary diameter and the slow projected rotation periods suggest the mutual-orbit plane of the system may have been inclined by tens of degrees relative to the line of sight during the observations. As such, observers should assume typical parameters for near-Earth binary systems of 2 to 4 hours for the primary rotation period and a mutual-orbit period between 12 and 24 hours. Read More

Arecibo Observatory Gets $19 Million NASA Grant to Help Protect Earth from Asteroids   September 29, 2019

Observ-a-thon reveals comet nucleus, holiday asteroid, and more!   December 28, 2018

Observatories Team Up to Reveal Rare Double Asteroid   July 12, 2018

Arecibo observed the near-Earth asteroid (505657) 2014 SR339   February 9, 2018

First Asteroid Detection since Hurricane Maria   December 12, 2017

Radar Observations and Shape Model of Asteroid 16 Psyche   Jul 21, 2017

Arecibo refines our knowledge of a potentially hazardous asteroid  Apr 17, 2017

Arecibo Observatory captures revealing images of Comet 45P/Honda-Mrkos-Pajdusakova   Feb 12, 2017

Discovery Announcement of Binary System (163693) Atira   Jan 20-23, 2017

Asteroids by the AO Planetary Radar Group


Astronomy Arecibo Observatory re-enters VLBI network with 21st-century backend

Arecibo Observatory (AO), with its recently upgraded Very Long Baseline Interferometer (VLBI) backend, successfully detected fringes in concert with antennae in the European VLBI Network (EVN). Read More


Education REU Student Mishaal Jan Publishes Summer Research Study about Massive Star Forming Region

Mishaal I. Jan, a 2019 Research Experience for Undergraduate (REU) summer student at the Arecibo Observatory, recently published her summer project on the detection of radio recombination lines in one of the most active star forming regions of our galaxy in the 2020 Compendium of Undergraduate Research in Astronomy and Space Physics.
Read More


Artistic impression of the cosmic cow. Credit: Shanghai Astronomical Observatory, China.

Astronomy AO helps detect Magnetar in the Cow

The Arecibo Observatory was one of 21 telescopes involved in the large-scale European Very Large Baseline Interferometry (VLBI) Network (EVN) radio observations of the astronomical explosion AT2018cow ('the Cow'). AO, which has the largest collecting area of all of the participating telescopes, helped boost the sensitivity of the extended VLBI baselines to detect the radio signals, producing high-resolution images that enabled scientists to determine that the highly unique supernova resulted in the creation of a magnetar – a neutron star with a very strong magnetic field. Read More



Astronomy AO Science at AAS, AOGS

The Arecibo Observatory Open House session was held on January 7 during the 235th American Astronomical Society (AAS) meeting in Honolulu, Hawaii.Read More

Flea on Pluto? Arecibo Observatory Helps Provide Unprecedented View of Pulsar  May 25, 2018

Pulsar Watchers Close In On Galaxy Merger History  Feb 28, 2018

Astronomers peer into the lair of a mysterious source of cosmic radio bursts  Jan 10, 2018

Why are Quasars so Bright?  JULY 18, 2017

The Mystery of Part Time Pulsars  JULY 18, 2017

Gaia Weighs in on the Pleiades Distance Controversy  Jan 27, 2017

Arecibo Puts Limits on Gravitational Wave Models   Jan 20, 2017


Space & Atmospheric Transforming the Arecibo Observatory into a Classroom

This past January, the Arecibo Observatory became the classroom for students from the Miami University in Ohio. Dr. Qihou Zhou, professor and chair of the Department of Electrical and Computer Engineering at the university, has held the “Undergraduate Hands-on Experience with Incoherent Scatter Radar” three-week winter term course at the observatory for the past six years. Read More


Inspiring experience for 17 Students from the Miami University - Ohio Campus

Prof. Qihou Zhou came to AO with 17 students from Miami University - Ohio Campus Space & Atmospheric Jan 3 -8, 2019

Recently, Prof. Qihou Zhou came to AO with 17 students from Miami University - Ohio Campus from Jan 3 to Jan 8 to use the Arecibo facility and study radar technology and space physics. This is the 4th study-away-at-Arecibo group in the past five years from Miami University. "Coming back is always an exciting and inspiring experience", said Prof. Zhou, a former Arecibo staff member until 2002.

Mid-latitude Radio-Frequency Auroras   Jul 21, 2017

Nighttime plasma lines are measured at Arecibo (Vierinen et al. [2017]).  Jun 15, 2017

The sensitivity of the Arecibo Observatory made possible to observe Gyrolines 

Creating space plasma from the ground  Jan 14, 2017


CAVEAT: The Arecibo Observatory is sponsored by the National Science Foundation. Any opinions, findings and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.