Areas of Expertise (7)
Color Selection of QSOs
Properties of Stars
Physics and Astronomy
Professor Newberg is a participant in the Sloan Digital Sky Survey, which will image 10,000 square degrees of the north galactic cap in five optical filters over the next five years. Additionally, the surey will obtain a million spectra of the galaxies (and hundreds of thousands of QSOs and stars) detected in the imaging survey. Newberg's current research is primarily related to understanding the structure of our own galaxy through using A stars as tracers of the galactic halo, and using photometrically determined metallicities of main sequence F-K stars to determine whether the thick disk is chemically distinct from the thin disk and galactic halo of our galaxy. She hopes that these studies will contribute to our understanding of how the Galaxy formed. Newberg has worked in many areas of astronomy over the course of my career. She did her PhD with the Berkeley Automated Supernova Search, which measured the supernova rates as a function of supernova type in Virgo-distance galaxies; and the Supernova Cosmology Project, which is measuring the cosmological parameters Omega and Lambda using the light curves of distant supernovae. She has published papers in diverse areas of galactic and extragalactic astronomy, including: supernova phenomenology, measuring cosmological parameters from supernovae, galaxy photometry, color selection of QSOs, properties of stars, and the structure of our galaxy.
University of California, Berkley: Ph.D.
Media Appearances (3)
Nuclear fission to DNA: Women's contribution to science that the world will not forget
Moneycontrol News online
Milky way structure | In 2015, Newberg and her team found that the Milky Way wad a corrugated plane instead of a flat structure. The research team also concluded that the galaxy is 50 percent larger than previously predicted. Newberg continues to study the Milky Way at the Rensselaer Polytechnic Institute, New York.
New 3D map of the Milky Way shows we live in a warped galaxy
Seems we weren't quite right about the Milky Way. Last year we learned that our home galaxy is bigger than we imagined, and now comes word that its shape isn't quite what many have believed it to be. Instead of being a mostly flat spiral disk of stars and gas, new research by astronomers in China and Australia shows that the Milky Way is significantly warped at its edges.
Dudley Observatory joining forces with miSci
The Daily Gazette online
The Dudley Observatory, created back in 1856 in what was called Goat Hill, will soon have a new home in Schenectady's Nott Terrace Heights. Headquartered at miSci since 2015, the Dudley Observatory will remain under the miSci umbrella. What will change, however, is that the observatory will be housed in its own building on the miSci grounds in downtown Schenectady, and will include a 14-inch Schmidt-Cassegrainian telescope and a removable roof for viewing the night sky.
An Orbit Fit to Likely Hermus Stream StarsMonthly Notices of the Royal Astronomical Society
Charles Martin, Paul M Amy, Heidi Jo Newberg, Siddhartha Shelton, Jeffrey L Carlin, Timothy C Beers, Pavel Denissenkov, Benjamin A Willett
2018 We selected blue horizontal branch (BHB) stars within the expected distance range and sky position of the Hermus Stream from Data Release 10 of the Sloan Digital Sky Survey. We identify a moving group of 19 BHB stars that are concentrated within two degrees of the Hermus Stream, between 10 and 14 kpc from the Sun. The concentration in velocity is inconsistent with a Gaussian distribution with 98 per cent confidence (2.33 sigma). The stars in the moving group have line-of-sight velocities of vgsr ∼ 50 km s−1, a velocity dispersion of σv ≲ 11 km s−1, a line-of-sight depth of ∼1 kpc, and a metallicity of [Fe/H] = −2.1 ± 0.4. The best-fitting orbit has a perigalacticon of ∼4 kpc, apogalacticon of ∼17 kpc, orbital period of ∼247 Myr, eccentricity e = 0.62, and inclination i ∼ 75° from b = 90°. The BHB stars in the stream are estimated to be 12 Gyr old. An N-body simulation of a mass-follows-light ultrafaint dwarf galaxy with mass 106 M⊙ and radius 40 pc is consistent with the observed properties. The properties of the identified moving group of 19 BHB stars are close enough to those of the Hermus Stream (which is traced predominantly in turnoff stars) that we find it likely that they are associated. If that is the case, then our orbit fit would imply that there is no relationship between the Hermus and Phoenix streams, as previously proposed.
Rings and Radial Waves in the Disk of the Milky WayThe Astrophysical Journal
Yan Xu, Heidi Jo Newberg, Jeffrey L. Carlin, Chao Liu, Licai Deng, Jing Li, Ralph Schönrich, and Brian Yanny
2015 We show that in the anticenter region, between Galactic longitudes of 110° < l < 229°, there is an oscillating asymmetry in the main-sequence star counts on either side of the Galactic plane using data from the Sloan Digital Sky Survey. This asymmetry oscillates from more stars in the north at distances of about 2 kpc from the Sun to more stars in the south at 4–6 kpc from the Sun to more stars in the north at distances of 8–10 kpc from the Sun. We also see evidence that there are more stars in the south at distances of 12–16 kpc from the Sun. The three more distant asymmetries form roughly concentric rings around the Galactic center, opening in the direction of the Milky Way's spiral arms. The northern ring, 9 kpc from the Sun, is easily identified with the previously discovered Monoceros Ring. Parts of the southern ring at 14 kpc from the Sun (which we call the TriAnd Ring) have previously been identified as related to the Monoceros Ring, and others have been called the Triangulum Andromeda Overdensity. The two nearer oscillations are approximated by a toy model in which the disk plane is offset by the order of 100 pc up and then down at different radii. We also show that the disk is not azimuthally symmetric around the Galactic anticenter and that there could be a correspondence between our observed oscillations and the spiral structure of the Galaxy. Our observations suggest that the TriAnd and Monoceros Rings (which extend to at least 25 kpc from the Galactic center) are primarily the result of disk oscillations.
The Seventh Data Release of the Sloan Digital Sky SurveyThe Astrophysical Journal Supplement Series
A Nebot, EH Neilsen Jr, HJ Newberg, et. al.
2009 This paper describes the Seventh Data Release of the Sloan Digital Sky Survey (SDSS), marking the completion of the original goals of the SDSS and the end of the phase known as SDSS-II. It includes 11,663 deg2 of imaging data, with most of the ~2000 deg2 increment over the previous data release lying in regions of low Galactic latitude. The catalog contains five-band photometry for 357 million distinct objects. The survey also includes repeat photometry on a 120° long, 2fdg5 wide stripe along the celestial equator in the Southern Galactic Cap, with some regions covered by as many as 90 individual imaging runs. We include a co-addition of the best of these data, going roughly 2 mag fainter than the main survey over 250 deg2. The survey has completed spectroscopy over 9380 deg2; the spectroscopy is now complete over a large contiguous area of the Northern Galactic Cap, closing the gap that was present in previous data releases. There are over 1.6 million spectra in total, including 930,000 galaxies, 120,000 quasars, and 460,000 stars. The data release includes improved stellar photometry at low Galactic latitude. The astrometry has all been recalibrated with the second version of the USNO CCD Astrograph Catalog, reducing the rms statistical errors at the bright end to 45 milliarcseconds per coordinate. We further quantify a systematic error in bright galaxy photometry due to poor sky determination; this problem is less severe than previously reported for the majority of galaxies. Finally, we describe a series of improvements to the spectroscopic reductions, including better flat fielding and improved wavelength calibration at the blue end, better processing of objects with extremely strong narrow emission lines, and an improved determination of stellar metallicities.