Related papers: A Vigorous Explorer Program

Continuous gravitational waves have the potential to transform gravitational wave astronomy and yield fresh insights into astrophysics, nuclear and particle physics, and condensed matter physics. We evaluate their detectability by combining…

The next decade of survey astronomy has the potential to transform our knowledge of variable stars. Stellar variability underpins our knowledge of the cosmological distance ladder, and provides direct tests of stellar formation and…

The Planet Hunting and Asteroseismology Explorer Spectrophotometer, PHASES, is a concept for a space-borne instrument to obtain flux calibrated spectra and measure micro-magnitude photometric variations of nearby stars. The science drivers…

In this White Paper, we emphasize the need for and the important role of plasma astrophysics in the studies of formation, evolution of, and feedback by Active Galaxies. We make three specific recommendations: 1) We need to significantly…

A few percent of all stars are variable, yet over 90% of variables brighter than 12 magnitude have not been discovered yet. There is a need for an all sky search and for the early detection of any unexpected events: optical flashes from…

Doing astronomy with photons of energies in excess of a GeV has turned out to be extremely challenging. Efforts are underway to develop instruments that may push astronomy to wavelengths smaller than $10^{-14}$~cm by mapping the sky in high…

Shemar et al. (2016) presented results based on the output of a feasibility study for the European Space Agency (ESA) on the use of X-ray pulsars for deep space navigation, a concept often referred to as 'XNAV'. Here we describe some of the…

Radio astronomy has benefited greatly from advances in technology and will continue to do so in the future. In fact, we are experiencing a revolution in the way radio astronomy is conducted as our instruments allow us now to directly…

The Mars Odyssey spacecraft carries two experiments which are capable of detecting cosmic gamma-ray bursts and soft gamma repeaters. Since April 2001 they have detected over 275 bursts and, in conjunction with the other spacecraft of the…

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the…

The core of scientific research is turning new ideas into reality. From the school science fair to the search for the secrets of dark energy, high-quality research consists of scientific investigation constrained within the scope of a…

The great success of the Rossi X-Ray Timing Explorer (RXTE) has given us a new probe to study strong gravitational fields and to measure the physical properties of black holes and neutron stars. Here, we describe a "next-generation" x-ray…

Since their first discovery in the late 1960s, Gamma-ray bursts have attracted an exponentially growing interest from the international community due to their central role in the most highly debated open questions of the modern research of…

NASA's Fermi space telescope has provided us with a bountiful new population of gamma-ray sources following its discovery of 150 new gamma-ray pulsars. One common feature exhibited by all of these pulsars is the form of their spectral…

THESEUS is a space mission concept, currently under Phase A study by ESA as candidate M5 mission, aiming at exploiting Gamma-Ray Bursts for investigating the early Universe and at providing a substantial advancement of multi-messenger and…

Radio astronomy provides a unique window on the universe, allowing us to study: non-thermal processes (galactic nuclei, quasars, pulsars) at the highest angular resolution using VLBI, with low opacity. It is the most interesting wave band…

The NASA program in X-ray astronomy has two long term goals: 1) to achieve sufficient angular resolution to image the event horizon of a black hole (0.1 micro arc sec) and 2) to achieve sufficient collecting area (50-150 sq m) and angular…

Our knowledge of the high-energy universe is undergoing a period of rapid change as new astronomical detectors of high-energy radiation start to operate at their design sensitivities. Now is a boomtime for high-energy astrophysics, with new…

We review some key issues pertaining to NASA's Research and Analysis programs, and offer recommended actions to mitigate or resolve these issues. In particular, we recommended that NASA increases funding to support a healthy selection rate…

Multi-messenger astronomy is becoming a major avenue to explore the Universe. Several well known astrophysical sources are also expected to emit other 'messenger' than photons: namely cosmic rays, gravitational waves and neutrinos. These…