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The Exoplanet Orbit Database (EOD) compiles orbital, transit, host star, and other parameters of robustly-detected exoplanets reported in the peer-reviewed literature. The EOD can be navigated through the Exoplanet Data Explorer (EDE) plotter and table, available on the World Wide Web at exoplanets.org. The EOD contains data for 1492 confirmed exoplanets as of 2014 July. The EOD descends from a table provided by Butler and coworkers in 2002 and the Catalog of Nearby Exoplanets (Butler and coworkers in 2006), and the first complete documentation for the EOD and the EDE was presented by Wright and coworkers in 2011. In this work, we describe our work since then. We have expanded the scope of the EOD to include secondary eclipse parameters and asymmetric uncertainties and expanded the EDE to include the sample of over 3000 Kepler Objects of Interest (KOIs) and other real planets without good orbital parameters (such as many of those detected by microlensing and imaging). Users can download the latest version of the entire EOD as a single comma separated value file from the front page of exoplanets.org.

We present a computationally tractable implementation of spectro-perfectionism, a method which minimizes error imparted by spectral extraction. We develop our method in conjunction with a full raw reduction pipeline for the MINiature Exoplanet Radial Velocity Array (MINERVA), capable of performing both optimal extraction and spectro-perfectionism. Although spectro-perfectionism remains computationally expensive, our implementation can extract a MINERVA exposure in approximately 30 minutes. We describe our localized extraction procedure and our approach to point-spread function (PSF) fitting. We compare the performance of both extraction methods on a set of 119 exposures on HD 122064, an RV standard star. Both the optimal extraction and spectro-perfectionism pipelines achieve nearly identical RV precision under a six-exposure chronological binning. We discuss the importance of reliable calibration data for PSF fitting and the potential of spectro-perfectionism for future precise radial velocity exoplanet studies.

The Second Workshop on Extreme Precision Radial Velocities defined circa 2015 the state of the art Doppler precision and identified the critical path challenges for reaching 10 cm s(-1) measurement precision. The presentations and discussion of key issues for instrumentation and data analysis and the workshop recommendations for achieving this bold precision are summarized here. Beginning with the High Accuracy Radial Velocity Planet Searcher spectrograph, technological advances for precision radial velocity (RV) measurements have focused on building extremely stable instruments. To reach still higher precision, future spectrometers will need to improve upon the state of the art, producing even higher fidelity spectra. This should be possible with improved environmental control, greater stability in the illumination of the spectrometer optics, better detectors, more precise wavelength calibration, and broader bandwidth spectra. Key data analysis challenges for the precision RV community include distinguishing center of mass (COM) Keplerian motion from photospheric velocities (time correlated noise) and the proper treatment of telluric contamination. Success here is coupled to the instrument design, but also requires the implementation of robust statistical and modeling techniques. COM velocities produce Doppler shifts that affect every line identically, while photospheric velocities produce line profile asymmetries with wavelength and temporal dependencies that are different from Keplerian signals. Exoplanets are an important subfield of astronomy and there has been an impressive rate of discovery over the past two decades. However, higher precision RV measurements are required to serve as a discovery technique for potentially habitable worlds, to confirm and characterize detections from transit missions, and to provide mass measurements for other space-based missions. The future of exoplanet science has very different trajectories depending on the precision that can ultimately be achieved with Doppler measurements.

We present a computationally tractable implementation of spectro-perfectionism, a method which minimizes error imparted by spectral extraction. We develop our method in conjunction with a full raw reduction pipeline for the MINiature Exoplanet Radial Velocity Array (MINERVA), capable of performing both optimal extraction and spectro-perfectionism. Although spectro-perfectionism remains computationally expensive, our implementation can extract a MINERVA exposure in approximately 30 minutes. We describe our localized extraction procedure and our approach to point-spread function (PSF) fitting. We compare the performance of both extraction methods on a set of 119 exposures on HD 122064, an RV standard star. Both the optimal extraction and spectro-perfectionism pipelines achieve nearly identical RV precision under a six-exposure chronological binning. We discuss the importance of reliable calibration data for PSF fitting and the potential of spectro-perfectionism for future precise radial velocity exoplanet studies.

The MINiature Exoplanet Radial Velocity Array (MINERVA) is a dedicated observatory of four 0.7 m robotic telescopes fiber-fed to a KiwiSpec spectrograph. The MINERVA mission is to discover super-Earths in the habitable zones of nearby stars. This can be accomplished with MINERVA's unique combination of high precision and high cadence over long time periods. In this work, we detail changes to the MINERVA facility that have occurred since our previous paper. We then describe MINERVA's robotic control software, the process by which we perform 1D spectral extraction, and our forward modeling Doppler pipeline. In the process of improving our forward modeling procedure, we found that our spectrograph's intrinsic instrumental profile is stable for at least nine months. Because of that, we characterized our instrumental profile with a time-independent, cubic spline function based on the profile in the cross dispersion direction, with which we achieved a radial velocity precision similar to using a conventional \"sum-of-Gaussians\" instrumental profile: 1.8 m s−1 over 1.5 months on the RV standard star HD 122064. Therefore, we conclude that the instrumental profile need not be perfectly accurate as long as it is stable. In addition, we observed 51 Peg and our results are consistent with the literature, confirming our spectrograph and Doppler pipeline are producing accurate and precise radial velocities.

The MINiature Exoplanet Radial Velocity Array (MINERVA) is a dedicated observatory of four 0.7 m robotic telescopes fiber-fed to a KiwiSpec spectrograph. The MINERVA mission is to discover super-Earths in the habitable zones of nearby stars. This can be accomplished with MINERVA’s unique combination of high precision and high cadence over long time periods. In this work, we detail changes to the MINERVA facility that have occurred since our previous paper. We then describe MINERVA’s robotic control software, the process by which we perform 1D spectral extraction, and our forward modeling Doppler pipeline. In the process of improving our forward modeling procedure, we found that our spectrograph’s intrinsic instrumental profile is stable for at least nine months. Because of that, we characterized our instrumental profile with a time-independent, cubic spline function based on the profile in the cross dispersion direction, with which we achieved a radial velocity precision similar to using a conventional “sum-of-Gaussians” instrumental profile: 1.8 m s−1 over 1.5 months on the RV standard star HD 122064. Therefore, we conclude that the instrumental profile need not be perfectly accurate as long as it is stable. In addition, we observed 51 Peg and our results are consistent with the literature, confirming our spectrograph and Doppler pipeline are producing accurate and precise radial velocities.

The Second Workshop on Extreme Precision Radial Velocities defined circa 2015 the state of the art Doppler precision and identified the critical path challenges for reaching 10 cm s−1 measurement precision. The presentations and discussion of key issues for instrumentation and data analysis and the workshop recommendations for achieving this bold precision are summarized here. Beginning with the High Accuracy Radial Velocity Planet Searcher spectrograph, technological advances for precision radial velocity (RV) measurements have focused on building extremely stable instruments. To reach still higher precision, future spectrometers will need to improve upon the state of the art, producing even higher fidelity spectra. This should be possible with improved environmental control, greater stability in the illumination of the spectrometer optics, better detectors, more precise wavelength calibration, and broader bandwidth spectra. Key data analysis challenges for the precision RV community include distinguishing center of mass (COM) Keplerian motion from photospheric velocities (time correlated noise) and the proper treatment of telluric contamination. Success here is coupled to the instrument design, but also requires the implementation of robust statistical and modeling techniques. COM velocities produce Doppler shifts that affect every line identically, while photospheric velocities produce line profile asymmetries with wavelength and temporal dependencies that are different from Keplerian signals. Exoplanets are an important subfield of astronomy and there has been an impressive rate of discovery over the past two decades. However, higher precision RV measurements are required to serve as a discovery technique for potentially habitable worlds, to confirm and characterize detections from transit missions, and to provide mass measurements for other space-based missions. The future of exoplanet science has very different trajectories depending on the precision that can ultimately be achieved with Doppler measurements.

The Second Workshop on Extreme Precision Radial Velocities defined circa 2015 the state of the art Doppler precision and identified the critical path challenges for reaching 10 cm s−1 measurement precision. The presentations and discussion of key issues for instrumentation and data analysis and the workshop recommendations for achieving this bold precision are summarized here. Beginning with the High Accuracy Radial Velocity Planet Searcher spectrograph, technological advances for precision radial velocity (RV) measurements have focused on building extremely stable instruments. To reach still higher precision, future spectrometers will need to improve upon the state of the art, producing even higher fidelity spectra. This should be possible with improved environmental control, greater stability in the illumination of the spectrometer optics, better detectors, more precise wavelength calibration, and broader bandwidth spectra. Key data analysis challenges for the precision RV community include distinguishing center of mass (COM) Keplerian motion from photospheric velocities (time correlated noise) and the proper treatment of telluric contamination. Success here is coupled to the instrument design, but also requires the implementation of robust statistical and modeling techniques. COM velocities produce Doppler shifts that affect every line identically, while photospheric velocities produce line profile asymmetries with wavelength and temporal dependencies that are different from Keplerian signals. Exoplanets are an important subfield of astronomy and there has been an impressive rate of discovery over the past two decades. However, higher precision RV measurements are required to serve as a discovery technique for potentially habitable worlds, to confirm and characterize detections from transit missions, and to provide mass measurements for other space-based missions. The future of exoplanet science has very different trajectories depending on the precision that can ultimately be achieved with Doppler measurements.

In order to understand changes in gene expression that occur as a result of age, which might create a permissive or causal environment for age-related diseases, we produced a multi-timepoint Age-related Gene Expression Signature (AGES) from liver, kidney, skeletal muscle and hippocampus of rats, comparing 6, 9, 12, 18, 21, 24 and 27-month old animals. We focused on genes that changed in one direction throughout the lifespan of the animal, either early in life (early logistic changes); at mid-age (mid-logistic); late in life (late-logistic); or linearly, throughout the lifespan. The pathways perturbed as a result of chronological age demonstrate organ-specific and more global effects of aging, and point to mechanisms that might be counter-regulated pharmacologically in order to treat age-associated diseases. A small number of genes were regulated by aging in the same manner in every tissue, suggesting they may be more universal markers of aging. Footnotes * https://www.ncbi.nlm.nih.gov/sra/?term=PRJNA516151

We investigate the stellar metallicity ([Fe/H] and [M/H]) dependence of giant planets around M dwarfs by comparing the metallicity distribution of 746 field M dwarfs without known giant planets with a sample of 22 M dwarfs hosting confirmed giant planets. All metallicity measurements are homogeneously obtained through the same methodology based on the near-infrared spectra collected with a single instrument SpeX mounted on the NASA Infrared Telescope Facility. We find that 1) giant planets favor metal-rich M dwarfs at a 4-5\\(\\sigma\\) confidence level, depending on the band of spectra used to derive metallicity; 2) hot (\\(a/R_\\ast\\leq 20\\)) and warm (\\(a/R_\\ast> 20\\)) Jupiters do not show a significant difference in the metallicity distribution. Our results suggest that giant planets around M and FGK stars, which are already known to prefer metal-rich hosts, probably have a similar formation channel. In particular, hot and warm Jupiters around M dwarfs may have the same origin as they have indistinguishable metallicity distributions. With the refined stellar and planetary parameters, we examine the stellar metallicities and the masses of giant planets where we find no significant correlation. M dwarfs with multiple giant planets or with a single giant planet have similar stellar metallicities. Mid-to-late type M stars hosting gas giants do not show an apparent preference to higher metallicities compared with those early-M dwarfs with gas giants and field M dwarfs.