Jul 12, 2018 - A new paper by Dan Stevens, Scott Gaudi, and Keivan Stassun, entitled
Measuring Model-independent Masses and Radii of Single-Lined Eclipsing Binaries: Analytic Precision Estimates, describes how the advent of SPHEREx and Gaia spectrophotometry, combined with existing broadband flux measurements, will measure nearly all the flux from intermediate- and low-mass stars. These data will permit direct bolometric flux measurements at high precision without needing to infer them from model stellar atmospheres. The bolometric fluxes can be combined with effective temperatures and parallaxes to calculate precise stellar radii (and, for stars with transiting/eclipsing companions, companion radii) empirically, or with parallaxes and radii from double-lined EBs to calculate empirical effective temperatures that can be used to resolve discrepancies between different effective temperature scales.
This paper was recently accepted for publication in the Astrophysical Journal.
Jun 6, 2018 - A new review paper by Salvato et al., entitled
The many flavours of photometric redshifts,
gives an overview of how photometric redshift techniques have evolved
and improved over several decades. It also points out that SPHEREx, with its 96 bands between 0.7 and 5 microns,
will have unique applications for measuring galaxy redshifts.
The Salvato et al. review article appears in Nature Astronomy.
May 24, 2018 - The SPHEREx Concept Study Report has been submitted to NASA!
May 23, 2018 - Professor Scott Gaudi from The Ohio State University gave a colloquium entitled "KELT, TESS, and Gaia: The Era of Precision Stellar Astrophysics and Exoplanetology" at Caltech on Wednesday, 23 May. He pointed out that SPHEREx, in combination with Gaia, would produce more precise radii for the host stars of planets discovered by TESS [and other transit surveys], which in turn could determine the radii of exoplanets to better than 1%. In addition, the SPHEREx data could lead to model-independent maps of interstellar extinction in the solar vicinity.
May 21, 2018 - One of the prime scientific motivations for SPHEREx is to understand
whether biogenic ices -- water in particular -- form within the disks surrounding nascent stars, or are brought
in to those disks from their surrounding molecular clouds. A recent article in the New York Times
illustrates an analogous investigation of
how water may have been transported to Earth by asteroids.
The research reveals another way in which water can move, in the planetary systems
that are created from the protostellar disks that the SPHEREx team will investigate.
Apr 2, 2018 - The Hunt for Observable Signatures of Terrestrial Systems (HOSTS)
recently published a paper
by S. Ertel et al.,
describing how they detected dust from the habitable zone around bright
nearby stars. HOSTS used an interferometric nulling technique to suppress
light from the central star, emphasizing the spatially extended emission
from the warm dust in the habitable zone. The detection rate in their
30-star sample was 18%. Which implies that the all-sky
SPHEREx survey will be observing enormous numbers of such systems.
SPHEREx can potentially leverage its high spectral sensitivity and many
spectral channels to detect
them directly, by separating the warm dust emission from that of the central
Feb 8, 2018 - Last week, SPHEREx PI Jamie Bock gave the weekly colloquium at the
Harvard-Smithsonian Center for Astrophysics. His talk, which was webcast live,
is available for viewing online (one hour video).
Feb 1, 2018 - The SPHEREx team just concluded a productive
commmunity workshop in Cambridge to elucidate the
scientific overlap and synergies between SPHEREx and other missions, both ground- and space-based.
A white paper is now being written to document the areas in which SPHEREx will enhance the scientific output
of these other observatories, and vice-versa.
Oct 4, 2017 - The SPHEREx team announces a 2nd community workshop!
SPHEREx Synergies will be held at the Harvard-Smithsonian Center
for Astrophysics in Cambridge on January 30 and 31, 2018.
Aug 16, 2017 - SPHEREx and the other MIDEX finalists are described in this
Science article . SPHEREx itself is described in more detail on
Aug 9, 2017 - Wonderful news! We learned today that
NASA chose SPHEREx
for a Phase A study! The SPHEREx team will receive $2M to carry out
the nine-month study to refine the mission concept.
NASA will make the final selection "by 2019."
More details will be provided here as soon as they become available.
Mar 22, 2017- As planned, the SPHEREx team responded in writing to resolve
NASA's questions about potential major weaknesses in our MIDEX proposal.
This is standard procedure for MIDEX proposals at this stage.
Jan 4, 2017 - We are disappointed not to have been selected as a NASA SMEX
this round. NASA chose the
Imaging X-ray Polarimetry Explorer
(IXPE), a mission led by Marshall Space Flight Center. We wish them the very best of luck.
Dec 15, 2016 - An enhanced version of SPHEREx was submitted as a NASA
Medium-Class Explorer (MIDEX),
with Step-1 selections expected in July 2017. If approved, the augmentations will make SPHEREx
a significantly more powerful survey telescope for the astronomical community as a MIDEX.
Jul 18, 2016 - The SPHEREx step-2 proposal Concept Study Report was submitted to NASA!
Jun 16, 2016 - The detector sampling algorithm to be implemented
by SPHEREx has now been described in detail by
Zemcov et al., 2016,
now accepted by JAI!
Feb 24-26, 2016 - The SPHEREx team held a very successful
community-oriented science workshop at CalTech.
It was attended by more than 50 scientists from a wide range of disciplines,
including galactic, extragalactic, and planetary science. A
describing the science topics was recently posted on arxiv. The attendees on day two:
Nov 6, 2015 - SPHEREx will be featured at the upcoming January AAS meeting in Kissimmee, in session 147 on Tuesday January 5. In addition to the SPHEREx observatory and the all-sky spectral survey, the presentations will describe the three main research themes being developed by the SPHEREx science team, and the many science opportunities that SPHEREx will create for the wider astronomical community.
Oct 23, 2015 - PI Jamie Bock summarized the status and goals of SPHEREx to NASA's Astrophysics Subcommittee. The full presentation can be downloaded here.