From CFHT and Gemini: ” New clues about the early evolution of the Solar System revealed with simultaneous observations on Maunakea”

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Canada France Hawaii Telescope


Gemini Observatory
Gemini Observatory

Science Contacts:
Wesley Fraser
Col-OSSOS Principal Investigator
Queen’s University, Belfast, UK
Email: wes.fraser”at”
Office: +44 (0) 74 02 46 21 34
Cell: +44 074 024 621 34

Meg Schwamb
Gemini Observatory
Hilo, Hawai‘i
Email: mschwamb”at”
Office: 808 074-2593
Cell: 808 315-8014

Michele Bannister
Col-OSSOS collaborator
OSSOS Core member
Queen’s University Belfast
Email: m.bannister”at”
Phone: +44 074 555 471 79

JJ Kavelaars
Col-OSSOS collaborator
Herzberg Institute, Victoria, BC, Canada
Email: jjk”at”
Phone: +1 778 677 3131

Media Contact:

Peter Michaud
Public Information and Outreach Manager
Gemini Observatory
Hilo, Hawai‘i
Email: pmichaud”at”
Desk: 808 974-2510
Cell: 808 936-6643

Mary Beth Laychak
Outreach Manager
Canada-France-Hawaii Telescope
Email: mary”at”
Phone: 808 885-3121

Emma Gallagher
Communications Officer
Queen’s University, Belfast, UK
Email: emma.gallagher”at”
Phone: 028 9097 5384

Artist’s conception of a loosely tethered binary planetoid pair like those studied by Fraser et al. in this work which led to the conclusion that Neptune’s shepherding of them to the Kuiper Belt as gradual and gentle in nature. Credit: Gemini Observatoryy/AURA, artwork by Joy Pollard.

An international team of astronomers led by Wes Fraser of Queen’s University in Belfast used CFHT and Gemini simultaneously to discover a new type of Kuiper Belt Object (KBO) called “Blue Binaries”. The wide separation and color of these cold classical Kuiper Belt objects are providing important clues on the early evolution of the solar system. Their findings are published in the April 4 edition of Nature Astronomy.

“It’s a kinder, gentler Neptune,” says Gemini astronomer Meg Schwamb in describing a new result that leaves little doubt about how Neptune gently swept a class of planetoid pairs into the outer Solar System.

The Kuiper Belt is a circumstellar disk in the outer Solar System extending from beyond the orbit of Neptune to about 50 AU from the Sun.

Kuiper Belt. Minor Planet Center

The dynamical structure of the classical Kuiper Belt is divided in two components. The hot component is made of objects with eccentric and highly inclined orbits. They have a broad range of colors and about 10% of them are binaries. On the other hand, the cold component consist of objects with nearly circular orbits and low inclination. Their colors are typically red and have a higher occurrence of binaries, about 30%.

In February 2013, CFHT started the Outer Solar System Origins Survey (OSSOS), a Large Program that was awarded 560 hours of observing time over 4 years to find and track objects in the outer Solar System using Megaprime. OSSOS was completed in January 2017 and was highly successful, discovering nearly 1000 Trans Neptunian Objects that inhabit the outer Solar system.

The Colors of OSSOS (Col-OSSOS) program aimed to measure the colors of the cold classical Kuiper belt objects found by the OSSOS program. The team used CFHT and Gemini to gather colors from the ultraviolet to the infrared. The need for simultaneous observations came from the fact that these bodies rotate reasonably fast, on the order of one to a few hours so sychronous observations are important to ensure the team observed the same position at the same time in different colors. “Facilitating the simultaneous observations with the Col-OSSOS team and Gemini Observatory was challenging, but paved the way for a greater understanding of the origins of these blue binaries. In tandem, the two facilities observed all the colors of the outer solar system for the Col-OSSOS team” said Todd Burdullis, queued service observing operations specialist at CFHT who was in charge the CFHT observations and a coauthor of the study. Dr. Meg Schwamb, an astronomer at the Gemini Observatory and also a coauthor on the paper added: “Like synchronized swimmers, Gemini North and the Canada-France-Hawaii telescopes coordinated their movements to observe the Col-OSSOS Kuiper belt objects at nearly the same time. This created a unique dataset that the planetesimals’ brightness changes as they rotate, and led to this discovery.”

Five of the OSSOS objects are blue, very peculiar for objects belonging to the cold classical Kuiper Belt which are usually red. Additionally, these blue objects are wide binaries. The presence of so many widely separated blue binaries in the cold classical Kuiper Belt is difficult to explain.

In their Nature paper, the team explored different mechanism that would lead to this configuration and estimated that the best model reproducing the observations is a “push out” by the early phases of the outward migration of Neptune. In order keep the binary systems intact i.e. not splitting them apart, the outward motion of Neptune had to be very smooth and eventless. “This research has opened the window to new aspects of understanding the early stages of planet growth. We now have a solid handle on how and where these blue binaries originated” said Wes Fraser, first author of the study.

See the full article here .

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Gemini/North telescope at Mauna Kea, Hawaii, USA
Gemini/North telescope at Mauna Kea, Hawaii, USA

Gemini South
Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile


Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

CFHT Telescope
CFHT Interior