Science - USA (2021-11-12)

SCIENCE science.org 12 NOVEMBER 2021 • VOL 374 ISSUE 6569 803

scope focusing on habitable exoplanets, and
observatories sensitive to x-rays and far-in-
frared light. The survey committee, however,
found the missions would be more expensive
and take longer than NASA estimated. Even
a smaller variant of the large optical tele-
scope known as LUVOIR-B, with an 8-meter
mirror, would cost $17 billion and take 20
years to develop. NASA’s version of LUVOIR
“would have saturated the budget for several
decades,” Harrison says. “We wouldn’t be
able to develop the others, and the science
really requires multiple wavelength ranges.”
The panel found that with just a 6-meter
mirror, a telescope like LUVOIR could
achieve its most pressing task: figuring out
whether a sample of Earth-like planets har-
bor life. “If you don’t find any life you want a
robust enough sample to say, yes, life is really
rare,” Harrison says. The downsizing would
keep the cost to $11 billion and allow NASA to
develop later x-ray and far-infrared flagships.
They too would be scaled down, to about
$4 billion each from NASA proposals that
were twice as expensive. The teams behind
those proposals are disappointed, but can
see the logic. “Resources are limited, but this
is suggesting a way forward,” says Feryal Özel
of the University of Arizona, one of the lead-
ers of Lynx, the proposed x-ray observatory.
The committee also recommended that
NASA begin a one-per-decade series of me-
dium-size astrophysics missions—telescopes
with more targeted goals and smaller suites
of instruments. With budgets of $1.5 bil-
lion each, these would sit between flagships
and the small Explorer mission line of up to
$350 million. “You can do powerful things at
that scale,” Harrison says. And regular mis-
sions will allow NASA “to keep the science
going while developing the large things.”

The decision to support the ground-

based giants, the GMT and the TMT, came

after the two projects failed to raise enough

money from international partners and

private sources to continue to completion

(Science, 3 September, p. 1066). In 2018,

the longtime rivals made a joint pitch to

the decadal review, arguing that the two

scopes—one in Chile and one in Hawaii—

would give U.S. astronomers a view of the

entire sky. Europe’s Extremely Large Tele-

scope, in contrast, is further along than the

U.S.-led projects, but is a single instrument

in Chile. The report says NSF should as-

sess the viability of the two projects until

2023 before deciding whether to contribute

$1.7 billion to their $5.1 billion combined

budgets, buying at least 25% of observing

time on the two scopes.

The biggest potential show stopper,

Harrison says, is the unresolved issue of

where to build the TMT. The start of con-

struction at the project’s first choice site,

Mauna Kea in Hawaii, has been blocked for

7 years by groups including Native Hawai-

ians who consider the mountain sacred.

Federal support might help break the im-

passe by bringing another independent

assessment of environmental and cultural

impacts of building on Mauna Kea. “NSF

involvement will allow for a pause and re-

set of the discussion,” says Tyler Trent, a

physics graduate student at the University

of Arizona and a Native Hawaiian who sup-

ports the project.

In an unusual step for a report that largely

asks for new things and more money, the

survey says one NASA mission—an infrared

telescope that rides in the bay of a jumbo

jet—should end by 2023, consistent with

agency plans that have been repeatedly

thwarted by Congress. The Stratospheric

Observatory for Infrared Astronomy (SO-

FIA) costs $85 million per year to operate,

nearly as much as Hubble. But the survey

noted its “modest scientific productivity.”

Its director, Margaret Meixner, is surprised

and says the survey based its conclusion on

old data. In recent years, she says, SOFIA

has been “really transformed.” Others are

not convinced. “I’m delighted to see an end-

ing of support for SOFIA,” says Garth Illing-

worth of the University of California, Santa

Cruz. Continuing to fund it, “doesn’t send a

good message.” j

SPACE-BASED PRIORITIES

“Great

observatories”

program

$1.2 billion to mature tech

for a series of large missions

at different wavelengths

Large optical

telescope

First up, in the 2040s: an

$11 billion, 6-meter telescope

to seek Earth analogs

Probe missions A series of midsize $1.5 billion mis-

sions to maintain scientific diversity

GROUND-BASED PRIORITIES

U.S. extremely

large telescopes

$1.7 billion NSF share of $5.1 billion

Giant Magellan and Thirty Meter

telescope projects

Stage 4 Cosmic

Microwave

Background

Observatory

$273 million NSF share

and $387 million DOE

share of telescopes in Chile

and Antarctica

Next Generation

Very Large Array

$2.5 billion NSF share of $3.2 billion

array of 263 radio telescopes span-

ning North America

Astronomy’s next big things

The latest U.S. astronomy decadal survey sets

priorities for NASA, the National Science Foundation

(NSF), and the Department of Energy (DOE).

T

he word “underrepresentation”

doesn’t begin to describe the lack of

Black, Latino, and Native American

people in astrophysics, says Fiona

Harrison, co-chair of U.S. astronomers’

latest decadal survey, a 10-year priority-

setting exercise (see main story, p. 802). At

a total of 4%, “their representation is really

nonexistent.” In response, Harrison and the

steering committee created a panel, the

first for a decadal survey, on “the state of

the profession and societal impacts.” The

survey also breaks new ground in telling

universities, federal contractors, and fund-

ing agencies exactly what they need to do to

boost diversity. At the top of the list:

• Collect and disseminate demographic
  data on who applies for and receives
  federal grants. Harrison says, “We had
  a tremendously difficult time” obtain-
  ing that information from the National
  Science Foundation, NASA, and the
  Department of Energy.


• Expand funding for “bridge” programs
  that provide additional support for
  graduate students and that often part-
  ner predominantly white and minority-
  serving institutions.


• Promote people from underrepresented
  groups who are already in the profes-
  sion. “The representation of women at
  the entry level is actually quite good,”

Harrison says, “but it falls off” as you

climb the ranks.

• Improve how undergraduates are taught
  and mentored to reduce attrition.
  Students of color interested in majoring
  in astronomy or physics are three times
  less likely to earn a degree than their
  white counterparts.


• Treat harassment and discrimination as
  forms of scientific misconduct. “This is
  one of the biggest steps we can take” to
  reduce the current hostile environment,
  says co-chair Robert Kennicutt.


• Reward faculty who have a track record
  of increasing diversity through such
  mechanisms as additional administra-
  tive support and early-career awards.
  –Jeffrey Mervis

Astronomy turns its sights on itself