Astronomy - February 2014

(John Hannent) #1
ASTRONEWS C^70 carbon atoms, is the largest fullerene, which contains 70
molecule found in space so far.

FAST
FACT

2 atoms
Carbon monoxide
3 atoms
H 3 +

4 atoms
Formaldehyde

5 atoms
Methane

6 atoms
Formamide

8 atoms
Acetic acid
(vinegar)

10 atoms
Acetone

9 atoms
Ethanol

Number of types of different molecules detected in space

0

5

10

15

20

25

30

35

40

11 atoms
Cyanooctatetrayne

WWW.ASTRONOMY.COM 15

COSMIC
MOLECULES

ALMA watches black hole in action


Conventional wisdom holds
that the disks that form plan-
ets run out of gas after 10
million years, by which point
the growing star and its gas
giants have siphoned it out
of the system. Astronomers
have discovered, however,
that the system HD 21997,
235 light-years away and just
30 million years old, has
clung to its gas far longer
than that. Even more surpris-
ingly, they saw this gas min-
gling with the pulverized

rock that results when plane-
tesimals smash into each
other. The simultaneous pres-
ence of gas and dusty debris
is a previously unobserved
stage of solar-system forma-
tion and evolution.
Astronomers used the
Atacama Large Millimeter/
submillimeter Array (ALMA)
and the Herschel Space
Observatory — which see in
radio and infrared light,
respectively — to observe
both the dust and gas. The
gas, which scientists did not
expect, is some 30 to 60
times Earth’s mass. The
results appeared in the
October 20 issue of The
Astrophysical Journal and
the November 10 issue of
The Astrophysical Journal
Letters. — S. S.

45°
The angle at which the inner plan-
ets in the Kepler-56 system orbit
their host star, reported researchers
in the October 18 issue of Science.

Planets


are born in


hybrid disks


DUST BUSTER. The Atacama Large Millimeter/submillimeter Array
observed dust (left) and gas (right) in the HD 21997 solar system,
where planets are still forming. Scientists previously believed stars
and giant planets collected all the gas before the system was filled
with collision dust, but this hybrid disk shows that not to be the case.

MOLECULAR MASHUPS. Space is
full of complicated molecules. Scientists
have discovered structures composed
of up to 70 atoms. But the more compli-
cated a compound is, the less of it exists
in interstellar space. For example, scien-
tists have found 39 different molecules
made of two atoms — like carbon
monoxide — in space, while they have
only found three types of 11-atom com-
pounds — like cyanooctatetrayne.
ASTRONOMY: SArAH ScoLeS AnD roen KeLLy; DATA FroM
UniverSiTäT zU KöLn

JETTISONING JETS. Scientists used the Atacama Large Millimeter/
submillimeter Array (ALMA) to spy on the center of nGc 1433, seen
here in visible (blue) and radio (orange/red) light. The black hole hiding
there is quiet and calm, but ALMA’s sharp eye revealed that the object
is getting some action, according to a paper in the october Astronomy
& Astrophysics. The molecular gas around the galactic center has woven
itself into a spiral that feeds into the black hole, which then shoots jets
of material outward. nGc 1433’s puny jets are just 150 light-years long,
1,000 times smaller than those of active galaxies. — S. S.

ALMA (eSo/nAoJ/nrAo)/nASA/eSA/F. coMBeS

Á. KóSpÁL (eSA)/A. Moór (KonKoLy oBServATory)
Free download pdf