Announcement: Gemini Observatory

15 December 2018: Gemini Observatory announces the opportunity for new Large and Long Programs, with observations beginning in the 2019B semester. Letters of Intent to propose a new Large and Long Program are due February 4, 2019. Completed Proposals are due April 1, 2019.

16 October 2018: Thanks to two allocations of Director’s Discretionary Time and a successful Fast-Turnaround program, an international team (including Gemini Emeritus Astronomer Tom Geballe, who wrote this summary on behalf of the team) used Gemini North/GNIRS to follow the evolution of the near-infrared spectrum of the core-collapse supernova 2017eaw (ccSN 2017eaw) over three semesters. The data obtained from this relatively nearby event may help us to better understand the existence of dusty galaxies in the early, much more distant Universe. One of the unexpected discoveries in studies of the very early Universe is that many high redshift galaxies are “dusty.” These dusty galaxies exist as recently as several hundred million to a billion years after the Big Bang. The origin of this dust is somewhat of a mystery, because stars with masses similar to the Sun, which constitute the vast majority of stars in a galaxy, would not have evolved to the …

19 September 2018: Multi-conjugate adaptive optics technology at Gemini South reveals that young galaxies, with large amounts of star formation, and actively growing central black holes, were relatively compact in the early Universe. A team of astronomers led by Dr. Mark Lacy (National Radio Astronomy Observatory, USA) used advanced adaptive optics on the Gemini South telescope in Chile to obtain high-resolution near-infrared images of three fields from the Spitzer Extragalactic Representative Volume Survey (SERVS). Their sample includes several ultra-luminous infrared galaxies (ULIRGs) which the Herschel Space Observatory found to be undergoing large bursts of star formation within the first few billion years of the Big Bang. Such galaxies have hundreds of times the infrared luminosity of a normal galaxy such as the Milky Way. The high-resolution GeMS images reveal that the ULIRGs have messy, irregular structures indicating that they are the product of recent galactic interactions and mergers. Lacy explains, “The fact that …

27 August 2018: Using the Gemini North telescope in Hawai`i, an international team of astronomers from Brazil, Italy, the Netherlands, and the UK has discovered the most distant radio galaxy to date, at 12.5 billion light years, when the Universe was just 7% of its current age. The team used spectroscopic data from the Gemini Multi-Object Spectrograph (GMOS-N) to measure a redshift of z = 5.72 for the radio galaxy identified as TGSS J1530+1049. This is the largest redshift of any known radio galaxy. The redshift of a galaxy tells astronomers its distance because galaxies at greater distances move away from us at higher speeds, and this motion causes the galaxy's light to shift farther into the red. Because light has a finite speed and takes time to reach us, more distant galaxies are also seen at earlier times in the history of the Universe. The study was led by graduate students Aayush …

17 July 2018: Scientists announced the discovery of 12 new moons orbiting the planet Jupiter, including one that bucks the trend by orbiting in the opposite direction from others of its ilk. Gemini observations confirmed this jovian oddball, dubbed Valetudo, after the great-granddaughter of the god Jupiter. The Gemini director’s discretionary observations were made using the Gemini Multi-Object Spectrograph (GMOS) on the Gemini North telescope atop of Hawaii’s Maunakea. Read more about this discovery in the Association of Universities for Research in Astronomy (AURA) press release that follows. Scientists using National Science Foundation Observatories find 12 new moons of Jupiter Sometimes you find something you weren’t even looking for. A team of scientists led by Carnegie’s Scott S. Sheppard, during a search to find very distant Solar System objects, just announced the discovery of twelve new moons orbiting Jupiter. The moons were first found in the spring of 2017 when the team was …

9 July 2018: The frustrating search for intermediate mass black holes is advancing thanks to Gemini observations of a “belch” which escaped when a black hole devoured a star. The black hole powering the blast weighed in at a few tens of thousand solar masses and is quite possibly a missing link between supermassive and stellar mass black holes. After 10 years of searching, an international team of astronomers used Gemini South, and space-based telescopes, to probe a luminous X-ray outburst unlike any seen before. The outburst was unusual because it appears to be the result of a “tidal disruption event” (TDE), in which a massive black hole slurps up an entire star, but this particular event did not occur within the center of a galaxy, where the most massive black holes reside. In their investigation, the researchers measured the mass of the black hole that powered the outburst and found it was …

31 May 2018: A new study using Gemini data reveals that the ratio of binary stars in Kepler’s K2 exoplanet host stars is similar to that found elsewhere in our neighborhood of the Milky Way. According to lead author Dr. Rachel Matson of NASA’s Ames Research Center, “While we have known that about 50% of all stars are binary, to confirm a similar ratio in exoplanet host stars helps set some important constraints on the formation of potential exoplanets seen by Kepler.” Until recently, astronomers generally focused on single exoplanet host stars, believing that planets form primarily around lone stars like our Sun. However, the research led by Matson, who’s team observed 206 star systems, demonstrates that the influence of a neighboring star does not appear to deter planet formation. The presence of a very close neighboring star produces enormous collateral effects on a planetary system, possibly ejecting planets into interstellar space, or …

6 June 2017: The first exoplanet discovered using the Gemini Planet Imager (GPI) is a young, cool object between 2–10 Jupiter masses. Identified as 51 Eridani b, new research indicates that its color is redder than similar brown dwarfs and might be due to clouds in its atmosphere. The research also hints that the formation of this exoplanet is likely due to the collapse of icy disk materials followed by the accretion of a thick gas atmosphere – much like the process astronomers think probably formed the gas giants in our Solar System. An international team of astronomers led by Abhijith Rajan (School of Earth and Space Exploration, Arizona State University) observed the exoplanet 51 Eri b using GPI spectroscopy and determined that the planet is redder than similar brown dwarfs seen elsewhere. "This might be due to presence of clouds, similar to young L-type planetary mass companions," said Rajan. "A possible reason …

11 May 2017: Researchers combine images from Gemini South’s wide-field adaptive optics system (GeMS/GSAOI) with data from the Hubble Space Telescope (HST) to determine the proper motion of a distant cluster of stars. The observations, the first to use ground-based adaptive optics to precisely measure the motion of a cluster at such a large distance, allowed astronomers to set a lower limit for the mass of our Milky Way while providing clues about the cluster’s origin. A study of the proper motion (apparent motion in the sky due to an object's motion around our galaxy) of several substructures across the Milky Way’s halo is underway at Gemini South. As part of this study the team used Adaptive Optics (AO) at Gemini South, along with data from HST, to focus on a distant cluster called Pyxis. The work allowed the team to set a lower limit for the Milky Way’s mass of 950 million …

23 March 2017: Using the Gemini Planet Imager (GPI), a team of astronomers led by J. Chilcote (University of Toronto) found that the low mass stellar companion β Pictoris b is about 13 times more massive than Jupiter with a surface temperature of about 1720 K. While these parameters are in good agreement with earlier observations, they allow better comparisons with planetary evolution models. The Gemini data indicate that β Pictoris b best matches an exoplanet with an atmosphere like that of a low-surface gravity (L21) brown dwarf. Observations at the Gemini South telescope in Chile, using the Gemini Planet Imager (GPI), are refining our understanding of the β Pictoris system. The system contains the ~ 13 Jupiter mass companion β Pictoris b which is at the mass boundary sometimes used to distinguish between an exoplanet and a brown dwarf. Brown dwarfs are objects that are not massive enough for sustained nuclear reactions. …

23 February 2017: Using the Gemini Multi-Object Spectrograph (GMOS) on Gemini South, a team led by Jay Farihi (University College London) found, for the first time, a dust and debris disk surrounding a binary star with a white dwarf as a substellar companion. To date, almost all of the known planetary systems which include a white dwarf are single stars. Using GMOS spectra Farihi et al. identified critical metal features in the spectrum as well as the higher Balmer lines. From the Gemini data the team estimated a surface temperature of 21,800 Kelvin (about 3.5 times hotter than the Sun) and a mass of ~0.4 solar masses for the white dwarf star and a mass of ~0.063 solar masses for the companion. The research is published in the February 27th online issue of Nature Astronomy. The following text is provided verbatim from the University College London press release: Evidence of planetary debris surrounding …

22 February 2017: On February 17th Gemini reached another significant milestone with the celebration of the official handover to Base Facility Operations (BFO) at Gemini South. It took more than 2 years to complete this important step and involved all departments from Gemini South. About a year ago, Gemini North reached the same milestone, so now both Gemini telescopes operate routinely from the base facilities in La Serena, Chile and Hilo, Hawai‘i. Atsuko Nitta, the BFO Project lead adds, ”... although we’ve been operating fully remotely at Gemini South since mid-November of last year, we have now signed off on all BFO work packages and it’s official – both Gemini telescopes are remotely operational!” Atsuko also notes that this move has a profound impact on our nighttime operations (with no losses in data acquisition or on-sky observing efficiencies). The move to BFO also significantly improves our environmental stewardship mostly due to fewer trips …

7 February 2017: Gemini follows up on candidate galaxies with fading active galactic nuclei (AGN) first identified thanks to the Galaxy Zoo citizen science project. Researchers find that these galaxies show a significant reduction in ionizing photons within the last 20,000 years. Additionally, the gas clouds around these fading AGN are dominated by rotation, unlike those around radio-loud AGN, which are outflows coming from the nuclei. William C. Keel (University of Alabama) and his collaborators used Hα narrowband filters on the Hubble Space Telescope (HST) in conjunction with multi-object spectroscopy with the Gemini Multi-Object Spectrograph (GMOS) integral-field unit (IFU) on the Gemini North telescope on Maunakea to observe a set of fading active galactic nuclei (AGN). These fading AGN, identified in the Galaxy Zoo project, appear to have experienced a significant reduction in luminosity within 20,000 years or less based on this research. This work focused on nine AGN which are accompanied by …

13 December 2016: Using spectroscopic data from the Gemini North telescope, researchers have probed a complex binary T Tauri system that hints at a hidden planetary body shrouded deep within a stellar environment at the late stages of formation. Nicole Arulanantham of Wesleyan University (Middletown, Connecticut, now at University of Colorado Boulder) and colleagues used the Gemini Near-InfraRed Spectrograph (GNIRS) on the Gemini North telescope to target the binary T Tauri system V582 Mon (KH 15D) — two K-type stars in a circumbinary ring that is inclined to the binary’s orbit. The team obtained data at three different orientations of the system’s two young stars, allowing them to study several key aspects of this complicated system — including characterising the photosphere and magnetosphere of the companion star (B), exploring a jet of material associated with a bipolar outflow, and probing the scattering properties of its circumbinary ring. The research uncovered an excess of …

26 October 2016: Summary: A team using the Gemini Multi-Conjugate Adaptive Optics System (GeMS) with the Gemini South Adaptive Optics Imager (GSAOI) have, for the first time, measured the stellar masses relative to the physical sizes of several galaxies in a cluster at a lookback time of about 5 billion years. The data suggest that the relationship between stellar mass and size has a constant slope over time. This leads to the conclusion that the most likely evolutionary course for the larger (more expansive) galaxies we see in the nearby Universe is either from the combination of smaller galaxies and/or outflows from black holes at galactic cores. During the past 20 years astronomers have developed a picture for the evolution of the size and structure of galaxies – from the formation of the first galaxies in the early Universe, to what we see today. One of the most important discoveries is that the …

20 October 2016: Jupiter’s moon Io is the most volcanically active world in our Solar System. Now, the longest series of frequent high-resolution tracking of Io’s thermal emission is providing insights on Io’s volcanoes thanks to a powerful joint observation program between the Gemini North telescope (with NIRI+Altair instrument) and the W.M. Keck Observatory. The observations use advanced adaptive optics technology to remove distortions caused by the Earth’s atmosphere and provide remarkably sharp imaging of Io’s volcanic activity over a period of 29 months. The results show patterns in the volcanic activity over time and location on the satellite, but also present many new questions. Compellingly, some of the eruptions appeared to progress across the surface over time, as if one somehow triggered another 500 kilometers away. According to University of California Berkeley (UCB) Graduate Student Katherine de Kleer, "While it stretches the imagination to devise a mechanism that could operate over distances …

20 September 2016: Astronomers studying a mysterious phenomenon known as Lyman-alpha blobs (LABs) have discovered several of these high-energy objects in galaxies that are much closer than previously known. The discovery is significant because these closer specimens are much easier to study, and because they live at a time when the Universe was much older and more mature, allowing astronomers to study their evolution with cosmic time. The observations are of a rare type of relatively nearby galaxy, engulfed in large clouds of ionized gas as a result of violent, energetic activity in their cores. These closer specimens were first described in 2013, catching the astronomers’ attention with their luminosities and sizes. Data taken with the Gemini Observatory quickly revealed that these galaxies are unparalleled by any other objects known in the nearby Universe. To understand their nature and formation, observations with the Chandra X-ray observatory, the GALEX UV satellite, and the mid-infrared …

16 August 2016: Gemini explores the possibility of short-lived optical emission (visible light) from the violent events that produce gravitational waves. Even before the announcement of the first gravitational wave detection by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in February of this year, theorists wondered if the extreme energy required to produce strong gravitational waves might also produce a detectable optical flash. Currently the most widely accepted explanation for gravitational wave events is the collision of black holes. The impact would send gravitational waves rippling through space at the speed of light. Thanks to LIGO the existence of gravitational waves is now confirmed, but unknown is the extent to which they might be accompanied by the emission of optical light or radiation at higher energies such as x-ray or gamma-rays. A recent study headed by Stephen Smartt at Queen’s University in Belfast and Ken Chambers from University of Hawai‘i could help answer this …

19 June 2016: View CFHT release. The novel collaboration between the Gemini Observatory and Canada-France-Hawai‘i Telescope (CFHT) called GRACES (Gemini Remote Access to CFHT ESPaDOnS Spectrograph), helped to characterize a “hot Jupiter” around the T-Tauri star V830 Tau. The work appears in the current advanced online issue of the journal Nature. GRACES uses an innovative 270-meter fiber cable to transport light from the Gemini 8-meter telescope to the ESPaDOnS Spectrograph at CFHT. The system began operating in late 2015 and now is a popular option allowing Gemini and CFHT users to perform high-resolution optical spectroscopy with Gemini North’s larger mirror. The Nature paper is available online (subscription required) and is summarized in the press release from Observatoire Midi Pyrenees in Toulouse, France and CFHT that follows (release is reproduced verbatim from original): Newborn Giant Planet Grazes its Sun For the last 20 years the giant planets known as hot Jupiters have presented astronomers …

24 May 2016: Using the Gemini Planet Imager astronomers have successfully monitored the motion of a planet around the forming exoplanet system orbiting the star HD 95086 and suggest that more unseen planets are present. The large international team, led by Julien Rameau, a postdoctoral researcher at the Université de Montréal (Canada), used the Gemini Planet Imager (GPI) at the Gemini South telescope in Chile to observe the system over a period from 2013 until early this year. “During this short time we directly imaged the exoplanet, known as HD 95086 b, a 4-5 Jupiter mass planet, and its motion,” says Rameau. With these data, Rameau and his team determined that this planet is orbiting nearly face-on from our perspective, at about 60 astronomical units or twice the distance between our Sun and Neptune, and it has a low eccentricity, or nearly circular, orbit. Rameau adds, “This extremely high-resolution imaging with GPI was …