Asteroid 1999 AN10 no longer dangerous
German amateur astronomers make crucial discovery on
Palomar plate - from 1955!
A trail of the much-discussed near earth asteroid 1999 AN10 has been
located and measured by two German amateurs, A. Gnädig and A. Doppler,
on the Digital Sky Survey (DSS) copy of a 45-min red-exposure Palomar Sky
Survey I (PSS) plate. This has enlarged the observed orbital arc of the
asteroid 130-fold and allowed for much more precise calculations into the
future. Computations by B. G. Marsden and G. V. Williams show convincingly
that the miss distance on 2027 Aug. 7.3 UT will be 0.0026 AU = 390 000 km.
The subsequent revolution period of a little over 1.74 years precludes the
possibility of any further significant approach to the Earth until Feb.
2076, when the miss distance can be expected to be less than 0.05 AU =
7.5m km (although it cannot be as small as 0.008 AU = 1.5m km).
No longer are there any possibilities for impacts in 2044 or 2046 for
which the probability had been as high as 1:100 000 in recent weeks. This
astonishing conclusion to the most interesting episode in the short history
of NEO astronomy (see Updates # 131 and
132) sheds a light on the value of old photographic
plates. And it raises the question why the PSS plates hadn't been checked
long ago for possible pre-discovery images of the asteroid. Automated systems
like "SkyMorph" should be able to catch similar asteroidal trails on current
sky survey images at once. SkyMorph had also been used to check for trails
in the PSS plates but missed the crucial one; the software has now been
updated.
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Minor Planet
Electronic Circular # 1999-N21 of July 12th, providing the new data
and analysis.
CCNet Special
of July 13th with first reactions to the developments. More stories
on July 14
and 16.
A SpaceViews story,
an MSNBC story
and a JPL Update.
Earth Impact
Possibilities from the NEO Dynamic Site (1998 OX4 is still there, with
1: 5 million chances of impact in 2044 and 2046).
Why SkyMorph didn't
find the image...
... but the German group did:
The 2 amateurs are working together with DLR; see also this
Press
Release and this
detailled story (in German).
A
particulary stupid German TV report on the 'dangerous asteroid' that
had aired just hours before the MPEC came out - but wouldn't have been
true even before.
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Launches from Baikonur have resumed
Except for Proton rockets, the Baikonur cosmodrome in Kasachstan is
back in business, and two important missions have already launched:
a (final?) Progress supply ship for Mir on July 16th and a Russian-Ukrainian
science satellite, Okean-O, on July 17th. Meanwhile the investigation
into the Proton launch failure on July 5th is progressing: "The first
277 seconds of flight were nominal," according to the intitial analysis.
"Payload fairing separation had occurred at 186 seconds, which is normal
for a Russian payload.
At 277 seconds, Engine #3 on the second stage (one of four engines) began to
indicate a significant temperature increase in the combustion chamber.
Propellant lines began to melt, as well as the aluminum alloy fuel tank,
allowing fuel to spill out of the tank. The second stage was subsequently
destroyed in an explosive event. The third stage with the Breeze M and the
satellite intact flew on under its own inertia until 325 seconds when
destruction of the third stage began, due to aerodynamic forces. [...]
Debris fell in a track about 80 to 90 km long and 8-10 km wide."
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Mir supply launch coverage from
ABC,
BBC and
SpaceViews.
Okean launch coverage from
Fla. Today,
SpaceViews.
Proton crisis updates by ILS from
July 6,
July 9
and
July 14;
a more detailled report should be ready on July 19.
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7th to 8th mag. comet discovered; moves north
On July 13th, Australian amateur Daniel W. Lynn of Kinglake
West, Victoria, discovered an 8th-magnitude comet moving
rapidly northeast through the constellation Hydra. He was
using 10 x 50 binoculars. The comet is very low in the western
evening sky and most readily visible from the Southern
Hemisphere, but it will become better placed for Northern Hemisphere
observers by the end of the month. Later observations put Lynn more
at 7.0 magnitudes. The elongation from the Sun shrinks and the distance from
the Earth increases rapidly now, though, and perihelion is on July 23rd.
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Elements and Ephemeris for Comet C/1999 N2 (Lynn).
Recent Observations.
IAUC # 7224
of July 15th.
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Another 8 mag. discovery (quickly falling to 11 mag.):
Nova Aquilae 1999
There is also a photographic discovery of a nova by A.
Tago, Tsuyama, Japan, at a magnitude of 8.8 on July 13.558 UT. Tago
reports the coordinates as R.A. = 19h07m40s, Decl. = +12o32'.2 (equinox
2000). A CCD image taken by A. Nakamura, Kuma Kogen Astronomical
Obervatory, Japan, on July 14.513 UT places the position at R.A. =
19h07m36s.90, Decl. = +12o31'26".2 (equinox 2000). The nova was confirmed
spectroscopically by other Japanese observers. On subsequent days the
brightness of Nova Aquilae 1999 has fallen quickly: to 10th mag. on
July 14th and 11th mag. on July 15th.
Observatory, Okyama, Japan.
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AAVSO Newsflash # 467
of July 14.
Alert Notice # 261
of July 15th.
Charts for downloading.
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Major space mystery solved! :-)
Space historians have been scratching their heads for 30 years: What
did Neil Armstrong really say when he stepped off the LEM -
and what did he mean to say? The sound from the Moon was surprisingly
clear, yet there was static; something could get lost. And now Armstrong,
in an extremeley rare public appearance, has set the record straight:
He wanted to say "one small step for a man, one giant leap
for mankind," and he thought that he did so. But after listening
carefully to recordings of his famous words he now admits that he
actually forgot the "a." And he is asking writers to add it in parenthesis:
"It's one small step for (a) man,
one giant leap for mankind."
These comments were made early in a unique 45 minutes news conference
with four Apollo astronauts (from the missions 7, 11 and 17)
at the Kennedy Space Center Visitors Center late on July 16th that was
carried by TV news channels around the world. Even a few days before
the reclusive Armstrong was expected not to attend any news conferences
or interviews, and so most questions were addressed to him. Armstrong
actually seemed to enjoy the spectacle after a while, and when asked
whether he would trade his moon walk for a life in privacy he replied
with a clear "Never!" At the end of the event Armstrong got applause from
the reporters when Eugene Cernan (Apollo 17; the last man on the Moon)
stressed that Neil's refusal to play out his role as a space hero was
simple dignity.
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Transcript
of the news conference courtesy of CNN.
Coverage of the news conference from
BBC,
CNN,
Florida Today,
AP.
The
Washington Post on Armstrong's life - and
Die
ZEIT on Armstrong's words (in German & before the news conference)...
NASA Apollo 11 anniversary site.
A
book on the Apollo missions - online as PDF files.
Coverage of the 30th anniversary by
Florida Today (1969 stories),
Florida Today (1999 stories),
CNN,
ASTRONET.
Apollo Special pages from
Boeing,
the Newseum,
The History
Place, the
the Nat'l Air & Space Museum, the
BBC, CNN and
Rheinische
Post.
A major
NYT Magazine article on the race to the Moon.
And some links from the
New
Scientist.
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Head of NASM dies in glider crash
Donald Engen had been the director of the
National Air & Space Museum in Washington, D.C., since 1996:
InfoBeat story,
Engen
obituary from the NASM.
MMT mirror aluminized inside the telescope - but
results not convincing
For the first time a major telescope mirror has been aluminized
while it was still inside the instrument:
Univ. of AZ Press Release. Later inspection showed, though, that the
aluminum layer is too inhomogeneous for astronomical work: After some
months of engineering experiments, the layer will be stripped and the
whole procedure tried again.
Merging galaxies caught in the act
HST images of more than a dozen very distant colliding galaxies indicate
that, at least in some cases, big massive galaxies form through collisions
between smaller ones, in a "generation after generation" never-ending
story: STScI
Press Release
(alternate
version),
ESA Science News,
discoverer's special
page,
BBC story.
Fullerenes found in Allende meteorite
Fullerenes, a new form of carbon previously made in the laboratory, also
exist in nature: They were identified in the Allende meteorite. The finding
indicates that these molecules could have been a factor in the early history
of Earth and might even have played a role in the origin of life:
U. of HI
Press Release,
BBC story.
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NASA, Boeing Sign X-37 Vehicle Agreement
NASA and Boeing have completed negotiations on a $173 million cooperative
agreement to develop an experimental space plane, formerly known as
Future-X:
Boeing Press Release,
NASA News Release, NASA's
Homepage
for Future-X, a
CNN story.
First fragment of Liberty Bell 7 raised, capsule still on the
ocean floor
A dye canister found next to the space capsule has been retrieved -
a dress rehearsal for the big catch:
Discovery Channel Update for July 13. But then the operations ran
into difficulties with the submersible that requires repairs, and the
first opportunity to raise the capsule is now July 18th:
July 16 dispatch, the
current
status of the operation.
U.S. congressman Brown dead: A strong NASA advocate has
passed away at 79 - his website,
a SpaceViews obituary,
Sensenbrenner's statement.
A conference on neutron stars & black holes was held in
Crete recently: a
NASA
report.
Element 114 has also been created, this time a rather
long-lived isotope, in a Russian lab:
BBC story.
A new launch calendar for the Ariane rockets has been
announced - but still no firm date for the 4th Ariane 5 launch.
Another amateur space shot fails in the U.K.:
BBC story.
The Tunguska expedition has begun: a
press release
from July 14th.
Another crater expedition simulates a Mars mission, in
particular high-speed, high-end collaborative information networking:
SFU Press
Release.
The first ST-ECF online newsletter with stories esp. for
image processing buffs is now
available!
The Meteor Shower Calendar for 2000 has been published by the
IMO.
And several Hawking lectures are online, on the
Universe &
everything.
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