ASTRONEWS
PLUTO
79,820 days until
your first birthdayMERCURY
124 birthdays
(and 39 days until your next one)VENUS
48 birthdays
(and 53 days until your next one)MARS
15 birthdays
(and 34 days until your next one)JUPITER
2 birthdays
(and 2,041 days until
your next one)SATURN
1 birthday
(and 10,561 days
until your next one)URANUS
19,727 days until
your first birthdayNEPTUNE
49,231 days until
your first birthdayFAST
FAC T12 ASTRONOMY • SEPTEMBER 2015
EUROPAN SEA SALT. Scientists discovered that dark material lining features on Europa’s surface could be salt
from the moon’s underground ocean, baked by radiation from Jupiter’s strong magnetic field.BRIEFCASE
COSMIC BBQ GIVES HOT START TO LIFE
DNA is the backbone of life on Earth. Explaining the dou-
ble helix’s origin has consumed careers since James
Watson and Francis Crick announced it in 1953.
Researchers from Berkeley Lab and the University of
Hawaii looked at its molecular precursors and found cos-
mic hot spots near dying carbon-rich stars are prime
places to form these nitrogen-rich molecular rings,
according to an April 20 Astrophysical Journal paper.- HIGH SCHOOL TEAM FINDS
STRANGE PULSAR
Massive stars explode as supernovae when they die, with
some leaving behind pulsars — rapidly spinning neutron
stars that shoot radio waves in bright beams. Only a
small number of those sit in binary star systems. And a
teenage team found the widest known orbit of any such
pulsar so far — once every 45 days — using data from
the Green Bank Telescope. Cecilia McGough from
Strasburg High School in Virginia and De’Shang Ray of
Paul Laurence Dunbar High School in Baltimore made
the find during a National Science Foundation workshop.
It was published June 1 in The Astrophysical Journal.
HUBBLE PICKS OUT A STAR NAMED NASTY
It’s big, bad, and dying fast. Astronomers writing in
Monthly Notices of the Royal Astronomical Society say
the strange star, called Nasty 1, could be living through a
brief transition phase experienced by massive stars. Nasty
is a Wolf-Rayet star. It’s much bigger than our Sun and
evolves fast, shedding hydrogen outer layers and reveal-
ing a hot, bright helium-burning core. That rapid evolution
also makes it hard to track its formation. Nasty is unique
because it’s surrounded by a pancake-like disk stretching
for trillions of miles. This could indicate Wolf-Rayets form
by stealing material from other stars. — Eric Betz
N
earby super-Earth 55 Cancri e is a
dynamic place — not to mention
inhospitable. This planet — twice
the radius of Earth and eight times
as massive — whirls around its star once
every 18 hours and is tidally locked so that
one side always faces the broiling sun and
the other the cold of space. In the span
of two years, astronomers have seen the
planet’s dayside temperature swing from
1,800° to 4,900° F (1,000° to 2,700° C). It
marks the first time scientists have been
able to discern such clear variability on
an exoplanet. The researchers need more
analysis before they can be sure of the
cause, but their current most likely theoryinvolves massive volcanic eruptions that
smother the world in gas and dust, block-
ing thermal emission from the planet.
55 Cancri e’s surface might be par-
tially molten anyway, but eruptions
could cause the rapid change in condi-
tions astronomers observed with NASA’s
Spitzer Space Telescope. Co-author Nikku
Madhusudhan explains, “The present
variability is something we’ve never seen
anywhere else, so there’s no robust con-
ventional explanation. But that’s the fun
in science — clues can come from unex-
pected quarters.” His team submitted their
results to Monthly Notices of the Royal
Astronomical Society. — Korey HaynesRAPID CHANGES ON A SUPER-EARTH
YOUNG, BRILLIANT, AND HIDDEN. The Arches
Cluster, about 25,000 light-years away toward the Milky
Way center, is the densest star cluster in our galaxy. Only
2 to 4 million years old and full of massive young stars,
the region is swamped with gas enriched by earlier
supernova explosions and thick dust that hides the star-
light from visible-light instruments. The Hubble Space
Telescope’s infrared camera spied through the murk to
take the above image. While the Sun’s nearest stellar
neighbor is just over 4 light-years away, the Arches Cluster
is only 1 light-year across. Yet in that cosmically tiny space,
the Arches packs in thousands of stars, including over 150
of the brightest stars in the galaxy, up to 100 times the
Sun’s mass, that will die in supernova explosions. — K. H.Densest star cluster
glows in infrared
HOW OFTEN DO
MARTIANS HAVE
BIRTHDAYS?
If we divided the year on other planets
into 12 equal months, each of Mercury’s
months would last 7 days and 8 hours, but
a month on Pluto would last 20.7 years.NASA/ESAVOLCANO WORLD.
This artist’s depic-
tion shows how thick
clouds of material from
eruptions on the par-
tially molten surface
of 55 Cancri e could
shroud the planet in
gas and dust, thus rais-
ing its temperature.
NASA/JPL-CALTECH/R. HURT (IPAC)HOW OLD? Let’s say today is your 30th birthday on Earth. How many would you have celebrated on the
other planets? Because Mercury and Venus orbit the Sun faster than Earth, you would have enjoyed more
birthdays on those worlds — not as many on the outer planets, however. ASTRONOMY: MICHAEL E. BAKICH AND ROEN KELLY