Page 12 -- Over The Edge -- April 1, 1997

Earth's Water from
space? Comet Could
Hold the Answer

Two-tailed Comet Hale-
Bopp, already visible to
the naked eye in much of
the northern hemisphere,
could be one of the
brightest comets ever,
shedding light on how the

Earth's oceans formed.
“You can't miss it. It looks
like a comet,” astronomer
Paul Feldman of Johns
Hopkins University said
Monday after his first non-
telescope view of the
brilliant white smudge in
the pre-dawn northeast
sky.

“This is not a hard object
to see,” said comet
expert Michael Mummo
of NASA's Goddard
Space Flight Center in
suburban Maryland.
“Anybody in any major
city in the’ world,
presuming they're not
looking directly into a
street light, can see this
comet.”

That is not quite true yet:

= viewers in Australia and

extreme southern South
America will not get a
good look until after April
1

But in the northern
hemisphere, this week
should be prime viewing
time because the
predawn sky will be
moonless until March 19
and the comet will also
be visible in the early
evening sky. At this point,
Hale-Bopp never sets at
some northern latitudes,
including Alaska and
‘Scandinavia.

Hale-Bopp is already
brighter than Comet
Hyakutake, which
streaked across the sky a
year ago, according to
Sky & Telescope, an
astronomy magazine that
operates a hotline and
website for late-breaking
celestial news.

The comet’s gassy tail
takes up 20 degrees of
the sky, Sky & Telescope
said, which is about twice
~ the size of a human fist
held at arm's length and
viewed against the
heavens. Hale-Bopp has
another tail as well, a

curved, shorter smudge
made up of dust.

What is not visible to
unaided eyes on Earth is

Hale-Bopp’s icy heart, a

25-mile-wide core more
than 10 times the size of
the average comet and
four times the size of the
storied Halley's Comet.

Unlike Hyakutake, a much
smaller, dimmer comet
that gave a great show
because it came within 9

million miles of Earth,

Hale-Bopp will not get
any closer than 122
million miles at its closest
pass, on March 23-24.
Hale-Bopp-the name
comes from its
discoverers, Alan Hale
and Thomas Bopp, who
first spotted it in 1995 —
has the potential to give
clues to the earliest
moments of the solar
system, Feldman said by
telephone.

The NASA is launching a
series of so-called
sounding rockets that will
rise above Earth’s
atmosphere to gauge the
composition of the comet
and then parachute

‘back down, Feldman

said.

lt could help confirm
what many scientists
already believe: that
water on Earth came
from comets that hit
Earth ses sunides =the
comets’ frozen core
melted to form oceans,
according to the theory.
lf the rocket data show
the same trace elements
present in the world’s
oceans are also present
in Hale-Bopp, this could
go a long way toward
proving the’ theory,
Mumma said - by
telephone.

Earth-based telescopes
can get some great views
of Hale-Bopp, but the
Hubble Space Telescope
will not. The comet's path
brings it too close to the
Sun and Hubble's
mechanisms are not
equipped to “look"
directly into the Sun.

Look UP

MARS rises early in the
evening in the east and is
visible in the southwest

great time to view it,
looking like a very bright
yellowish-reddish star. eclipse, see
Mars is at opposition, the
opposite side of Earth
from the Sun, on March
16. On March 23, MARS

partially eclipsed MOON.
SATURN is very low in the in binoculars.
west just after sunset. It in the early evening and
a bright pre-dawn skies, and at
high northern latitudes, it
is visible all night long.
is already brighter than
SATURN, Comet Hyakutake at is
peak last year.
It is much Bopp looks like a fuzzy
white patch surrounding
There was be a deep a somewhat brighter
PARTIAL ECLIPSE of the center.
MOON on March 23,
visible from throughout
most of the Americas and
EUrope (and
Africa (morning of the
24th). The partial eclipse
started -at 6:58 p.m. PST
(UT - 8 hours).

yellowish star.

MERCURY is very low in
the west after sunset, very
particularly on March 19

brighter than Saturn.

sing Copious
yp EE fiw

oe ae re ul
On UMmuKgyr ahs
The Btge OP Py

Way Up! OBJECTS TO
LOOK FOR IN THE NIGHT SKY

(NORTHERN LATITUDES)

the Earth's shadow, at
8:39 p.m. PST, and the
partial eclipse ended at
before dawn. Now is a 10:21 p.m. PST. MARS was
seen near and above the
MOON. For more on the

www.skypub.com/
eclipses/m970323a.shtml.
COMET HALE-BOPP

COMET HALE-BOPP is now
near the easy to see with the
naked eye and stunning

In the morning sky, look
for Hale-Bopp about a
quarter of the way above
the horizon in the east-
northeast about an hour
and a half to two hours
before sunrise.
Itreached pointing up and to the
its maximum, with 92% of left. The comet is to the
the Moon darkened by

lower left of the bright
star Deneb. In the
morning sky, the comet
will be getting lower and
moving toward the north-
northeast over the next
couple weeks.
Hale-Bopp is also now
visible low in the evening
sky. It will get higher and
much easier to see over
the next several days.
Look low in the northwest
just after the end of
evening twilight. Its tail is
pointing up and to the
right. Hale-Bopp will
continue to be visible
through atleast mid-April.
It reaches perihelion, its
closest approach to the
Sun on April 1.
Moonlight will
increasingly interfere with
observing Hale-Bopp
over the next several
days, but the comet
should still be visible as it
brightens. Moonless
viewing after the 25th
should be excellent. For
more on Hale-Bopp:
http://www.sji.org/ed/
halebopp.html.