Astronomy - USA (2022-02)

24 ASTRONOMY • FEBRUARY 2022

Mars gets

busy

LAST YEAR,

OUR TOP-RANKED

science story was Mars —

specifically, the launch of three

new robotic missions bound

for the Red Planet. This year,

Mars tops the list yet again

because now, those launches

have come to fruition.

First on the scene was the

United Arab Emirates’

al-Amal (Hope) orbiter, the

country’s first interplanetary

mission. Hope slipped into

Mars orbit Feb. 9, making the

UAE the fifth country to ever

reach the planet. The orbiter is

now studying Mars’ thin

atmosphere, tracking stats

such as temperature, humid-

ity, and dust levels throughout

the next martian year, which

lasts 687 Earth days.

The very next day, China’s

Tianwen-1 mission entered

orbit around Mars. Three

months later, early on May 15

Beijing time, the orbiter

released a capsule containing

a lander and rover, Zhurong,

bound for the surface. A suc-

cessful soft landing at Utopia

Planitia in Mars’ northern

hemisphere made China the

third country to land a craft

on the planet and the second

to deliver a rover. On May 22,

the solar-powered rover drove

off its platform to begin its

planned 90-day search for

subsurface water and ice, as

well as signs of life. By the end

of August, the rover had

driven more than 3,490 feet

(1,064 meters), having com-

pleted all its assigned tasks

and exceeding its original

mission parameters.

NASA’s Perseverance rover

reached Mars last — although

it landed before Zhurong —

arriving and landing Feb. 18.

Arecibo

Observatory

collapses

ON NOVEMBER 19, 2020, the

U.S. National Science Foundation (NSF)

announced it would decommission the

famed Arecibo Observatory in Puerto Rico.

The statement came following a three-month

period that saw the failure of first an auxil-

iary cable, then a main support cable, both

connecting the telescope’s 900-ton receiv-

ing platform to one of three support towers.

Engineers had determined repairs could not

be made without risking further damage to

the telescope or, more importantly, the safety

of construction workers and facility staff.

NSF planned to execute a controlled

demolition. But the observatory had other

ideas. Around 8 A.M. local time Dec. 1,

the receiving platform fell nearly 500 feet

(152 meters) into the 1,000-foot-wide (305 m)

dish below, destroying both with a crash.

“The loss of Arecibo was shocking —

there were several virtual online vigils held

in mourning by those who worked with the

telescope, and for the broader radio astron-

omy community,” says Yvette Cendes, a post-

doctoral researcher and radio astronomer at

the Harvard-Smithsonian Center for

Astrophysics in Cambridge, Massachusetts.

For 57 years, Arecibo’s huge white dish

was an icon amid the lush green jungle.

More than that, its scientific legacy stood

unmatched. The observatory had several

On Dec. 1, 2020, the receiving platform suspended above Arecibo Observatory’s vast dish suddenly

tumbled down, destroying the historic telescope less than a month after the National Science Foundation

announced it would be decommissioned. MICHELLE NEGRON, NATIONAL SCIENCE FOUNDATION

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historic notches in its belt, from spotting

the first binary pulsar system in 1974 to

identifying the first extrasolar planets in

1992. And although Arecibo had in
      recent years been surpassed in size by
      the Five-hundred-meter Aperture
      Spherical radio Telescope (FAST) in
      China, the newer facility is not a direct
      replacement. FAST currently lacks
      Arecibo’s planetary radar capability,
      which is needed to characterize the size
      and spin of near-Earth asteroids.
      Arecibo was also a vital link in the
      North American Nanohertz Observatory
      for Gravitational Waves, or NANOGrav.
      This network of observatories is search-
      ing for gravitational waves by studying
      how passing ripples in space-time affect
      the signals Earth receives from pulsars.
      Although NANOGrav’s ability to detect
      gravitational waves in the future will
      certainly diminish without Arecibo’s
      contributions, researchers do still have
      a wealth of past observations with the
      facility they can refer back to, according
      to the collaboration’s website.
      Naturally, researchers are looking
      to what comes next. On April 1, the
      National Astronomical Observatories of
      the Chinese Academy of Sciences opened
      FAST to the international community,
      accepting proposals from researchers
      around the world. Around the same time,
      “there was a call for white papers on ideas
      on how to replace Arecibo, and what to
      do with the site in general,” Cendes says.

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