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Call for Proposals

AO - Call for Proposals 2018

We invite proposals for the use of the Arecibo 305-m telescope for the Thursday, September 6, 2018 (17:00 AST, 21:00 UTC) , deadline. These requests should be for telescope usage within the six-month (or in some cases one-year) period beginning January 1, 2019. This call does not include proposals for the use of the HF Facility for ionospheric studies. Read More


Observatories Team Up to Reveal Rare Double Asteroid

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

New observations by three of the world‘s largest radio telescopes have revealed that an asteroid discovered last year is actually two objects, each about 3,000 feet (900 meters) in size, orbiting each other. Near-Earth asteroid 2017 YE5 was discovered with observations provided by the Morocco Oukaimeden Sky Survey on Dec. 21, 2017, but no details about the asteroid's physical properties were known until the end of June. This is only the fourth "equal mass" binary near-Earth asteroid ever detected, consisting of two objects nearly identical in size, orbiting each other. The new observations provide the most detailed images ever obtained of this type of binary asteroid. Read More

Arecibo observed the near-Earth asteroid (505657) 2014 SR339

Near-Earth asteroid (505657) 2014 SR339
Planetary February 9, 2018

Arecibo observed the near-Earth asteroid (505657) 2014 SR339 using its NASA-funded planetary radar system on February 9, 2018. Radar images reveal 2014 SR339 to have a lumpy, elongated shape at least 1.5 km long and a rotation consistent with the 8.7 hour period determined from optical lightcurves (B.D. Warner, MoreData!). Read More

Arecibo Planetary Radar Returns to Action with Images of Asteroid Phaethon   December 22, 2017

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

Flea on Pluto? Arecibo Observatory Helps Provide Unprecedented View of Pulsar

Pulsar PSR B1957+20

Pulsar Astronomy May 25, 2018:
Imagine being able to see a flea on the surface of Pluto. That’s a good way to describe what the Arecibo Observatory in Puerto Rico helped a group of Canadian researchers do. Read More

Pulsar Watchers Close In On Galaxy Merger History

NASA Merging Galaxies
Pulsar Astronomy Feb 28, 2018

For the past twelve years, a group of astronomers have been watching the sky carefully, timing pulses of radio waves being emitted by rapidly spinning stars called pulsars, first discovered 50 years ago. These astronomers are interested in understanding pulsars, but their true goal is much more profound; the detection of a new kind of gravitational waves. With a new, more sophisticated analysis, they are much closer than ever before. Read More

Astronomers peer into the lair of a mysterious source of cosmic radio bursts

Pulsar Astronomy Jan 10, 2018

Using the Arecibo Observatory in Puerto Rico and the Green Bank Telescope in West Virginia, a team from Universities Space Research Association (USRA) and other institutions today announced today at the American Astronomical Society’s winterAAS meeting that mysterious bursts of radio emission, called Fast Radio Bursts (FRB), may be coming from near a giant black hole. Read More

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

Arecibo Call for Ionospheric Modification (HF facility)

Space & Atmospheric Jul 21, 2017

The Arecibo Observatory invites you to submit proposals for the use of the HF facility during 2018. HF experiments at Arecibo are scheduled by demand in periods of 5-7 days around new moon. Proposals should specify the associated diagnostics required: the incoherent scatter radar (ISR), active and passive optical instruments and others. Read More

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.