Are We Alone? NASA's 30-Year Goal to Answer Astrophysics' Greatest Question
“For the first time, we will identify continents and oceans—and perhaps the signatures of life—on distant worlds,” says NASA in its 30-year vision for astrophysics.
The past 30 years has seen a revolution in astronomy and our understanding of the Universe. That’s thanks in large part to a relatively small number of orbiting observatories that have changed the way we view our cosmos.
These observatories have contributed observations from every part of the electromagnetic spectrum, from NASA’s Compton Gamma Ray Observatory at the very high energy end to HALCA, a Japanese 8-metre radio telescope at the low energy end. Then there is the Hubble Space Telescope in the visible part of the spectrum, arguably the greatest telescope in history.
It’s fair to say that these observatories have had a profound effect not just on science, but on the history of humankind.
So an interesting question is: what next? Today, we find out, at least as far as NASA is concerned, with the publication of the organisation’s roadmap for astrophysics over the next 30 years. The future space missions identified in this document will have a profound influence on the future of astronomy but also on the way imaging technology develops in general.
So what has NASA got up its sleeve? To start off with, it says its goal in astrophysics is to answer three questions: Are we alone? How did we get here? And how does our universe work?
So let’s start with the first question. Perhaps the most important discovery in astronomy in recent years is that the Milky Way is littered with planets, many of which must have conditions ripe for life. So it’s no surprise that NASA aims first to understand the range of planets that exist and the types of planetary systems they form. [See Corliss Tech Review Group]
The James Webb Space Telescope, Hubble’s successor due for launch in 2018, will study the atmospheres of exoplanets, along with the Large UV Optical IR (LUVOIR) Surveyor due for launch in the 2020s. Together, these telescopes may produce results just as spectacular as Hubble’s.
To complement the Kepler mission, which has found numerous warm planets orbiting all kinds of stars, NASA is also planning the WFIRST-AFTA mission which will look for cold, free-floating planets using gravitational lensing. That’s currently scheduled for launch in the mid-2020s.
Beyond that, NASA hopes to build an ExoEarth Mapper mission that combines the observations from several large optical space telescopes to produce the first resolved images of other Earths. “For the first time, we will identify continents and oceans—and perhaps the signatures of life—on distant worlds,” says the report.
To tackle the second question—how did we get here?—NASA hopes to trace the origins of the first stars, star clusters and galaxies, again using JWST, LUVOIR and WFIRST-AXA. “These missions will also directly trace the history of galaxies and intergalactic gas through cosmic time, peering nearly 14 billion years into the past,” it says.
And to understand how the universe works, NASA hopes to observe the most extreme events in the universe, by peering inside neutron stars, observing the collisions of black holes and even watching the first nanoseconds of time. Part of this will involve an entirely new way to observe the universe using gravitational waves (as long as today’s Earth-based gravitational wave detectors finally spot something of interest).
The technology challenges in all this will be immense. NASA needs everything from bigger, lighter optics and extremely high contrast imaging devices to smart materials and micro-thrusters with unprecedented positioning accuracy.
One thing NASA’s roadmap doesn’t mention though is money and management—the two thorniest issues in the space business. The likelihood is that NASA will not have to sweat too hard for the funds it needs to carry out these missions. Much more likely is that any sleep lost will be over the type of poor management and oversight that has brought many a multibillion dollar mission to its knees.
And while NASA hopes for a new generation of advanced technologies to make better space observatories, it is strangely quiet about the kind of technology that will be required to better manage these missions.
NASA might well argue in public that developing better management technology and techniques is not part of its core mission. But in private it must be thinking hard about how to reduce problems such as the cost and time overruns that have plagued the JWST.
The only way to change that will be to make better mission management a core goal.