Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: Hubble Finds That Even Massive Stars Just Fade Away
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FOR RELEASE: 9:00 a.m. (EDT) April 9, 1998
CONTACT: Ray Villard
Space Telescope Science Institute, Baltimore, MD
(Phone: 410-338-4514)
PRESS RELEASE NO.: STScI-PR98-16
HUBBLE FINDS THAT EVEN MASSIVE STARS JUST FADE AWAY
Pinpointing the rapidly fading ember of a recently burned out
star, NASA's Hubble Space Telescope is giving astronomers a better
estimate on just how big a star can be before it ultimately explodes
as a supernova.
Based on Hubble's detection of a rare, young white dwarf star,
astronomers conclude that its progenitor was a whopping
7.6 times the mass of our Sun. Previously, astronomers had
estimated that stars anywhere from 6 to 10 solar masses
would not just quietly fade away as white dwarfs,
but abruptly self-destruct in torrential explosions.
This new lower limit will help astronomers refine theories of how
galaxies developed in the early universe, determine the rate at which
supernovae enrich interstellar space with heavy elements for building
new generations of stars and planets, and estimate the number of
neutron stars in space (neutron stars are the crushed stellar cores
resulting from supernovae).
Rebecca Elson and Steinn Sigurdsson of Cambridge University,
and co-investigators, discovered the ultra-hot white dwarf during a
search in archival Hubble Wide Field Planetary Camera 2 pictures of
the young star cluster NGC 1818, located 164,000 light-years away
in the Large Magellanic Cloud -- a satellite galaxy of our Milky Way.
The trick was to identify a newly formed white dwarf that was still
exceptionally hot and bright immediately after the burnout and
collapse of its progenitor star. Such a dwarf would be so "young" -
relative to older fainter dwarfs in the cluster -- it would allow a direct
link back to the most massive stars now present in the cluster. That's
because the most massive stars are the shortest lived, and so are
first to burnout as white dwarfs.
Because the star cluster NGC 1818 is ten times larger than those
found closer to us within our own galaxy, chances were far better
for catching the young dwarf before it swiftly dimmed on its way to
the "graveyard" of faint dwarfs. Also, the cluster is only about
40 million years old, and so still contains massive stars.
Hubble is ideally suited for hunting for white dwarfs so far away
because its exquisite resolution can pinpoint them among the cluster's
crowded stellar population, and can easily detect the blue light from
the sizzling 50,000 degree Fahrenheit surface temperature of the
young dwarf.
Once the candidate star was identified, a spectrum of the star
obtained at the Anglo-Australian Observatory. "Our spectrum indicates
that it is neither a foreground nor background object, and detailed
modeling is underway to understand its exact evolutionary state," says
Elson.
The results will be reported in the Astrophysical Journal Letters.
-- end --
The Space Telescope Science Institute is operated by the
Association of Universities for Research in Astronomy, Inc., for NASA,
under contract with the Goddard Space Flight Center, Greenbelt, MD.
The Hubble Space Telescope is a project of international cooperation
between NASA and the European Space Agency.
EDITOR'S NOTE: Images to accompany this release are available
electronically via the World Wide Web at:
http://oposite.stsci.edu/pubinfo/1998/16 and via links in
http://oposite.stsci.edu/pubinfo/latest.html or
http://oposite.stsci.edu/pubinfo/pictures.html.
GIF and JPEG images are available via anonymous ftp to oposite.stsci.edu in
/pubinfo/gif/9816.gif and /pubinfo/jpeg/9816.jpg.
******************************
FOR RELEASE: 9:00 a.m. (EDT) April 9, 1998
PHOTO NO.: STScI-PRC98-16
HOT WHITE DWARF SHINES IN YOUNG STAR CLUSTER
A dazzling "jewel-box" collection of over 20,000 stars can be seen in
crystal clarity in this NASA Hubble Space Telescope image, taken with
the Wide Field and Planetary Camera 2. The young (40 million year old)
cluster, called NGC 1818, is 164,000 light-years away in the Large
Magellanic Cloud (LMC), a satellite galaxy of our Milky Way.
The LMC, a site of vigorous current star formation, is an ideal nearby
laboratory for studying stellar evolution.
The circled star is a young white dwarf star, which has only very recently
formed following the burnout of a red giant. Based on this observation
astronomers conclude that the red giant progenitor star was 7.6 times the
mass of our Sun. Previously, astronomers have estimated that stars
anywhere from 6 to 10 solar masses would not just quietly fade away
as white dwarfs but abruptly self-destruct in torrential explosions.
Hubble can easily resolve the star in the crowded cluster, and detect its
intense blue-white glow from a sizzling surface temperature of 50,000
degrees Fahrenheit.
IMAGE DATA
Date taken: December 1995
Wavelength: natural color reconstruction from three filters (I,B,U)
Field of view: 100 light-years, 2.2 arc minutes
TARGET DATA
Name: NGC 1818
Distance: 164,000 light-years
Constellation: Dorado
Age: 40 million years
Class: Rich star cluster
Apparent magnitude: 9.7
Apparent diameter: 7 arc minutes
Credit: Rebecca Elson and Richard Sword, Cambridge UK, and NASA
(Original WFPC2 image courtesy J. Westphal, Caltech)
Image files are available electronically via the World Wide Web at:
http://oposite.stsci.edu/pubinfo/1998/16 and via links in
http://oposite.stsci.edu/pubinfo/latest.html or
http://oposite.stsci.edu/pubinfo/pictures.html.
GIF and JPEG images are available via anonymous ftp to oposite.stsci.edu in
/pubinfo/gif/9816.gif and /pubinfo/jpeg/9816.jpg.
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: Full Data Sets From Galileo's First Six Orbits Now Available
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Galileo Solid State Imaging Full Data Releases
ALL IMAGES
obtained by the Galileo Solid State Imaging (SSI) system during the
spacecraft's first six orbits (G1, G2, C3, E4, E6) of Jupiter are now
validated and available.
Images and data obtained by NASA/JPL's Galileo mission have been available
on an ongoing basis during the spacecraft's journey through the Jovian
system in order to share with the public the excitement of exploration and
new discoveries being made via the NASA/JPL Galileo spacecraft. Galileo
scientists have a one year period set aside for the process of calibrating
and validating the data. The full digital images necessary for scientific
analysis are released within one year of receipt of an orbit's last data.
* IMAGE PRODUCTS from the ongoing public releases are available now in
multiple formats (including tiff, gif, pict, jpeg).
* ALL IMAGES from the first six orbits (G1, G2, C3, E4, and E6) are
merged and validated and available via the Planetary Data System.
* Nominal Mission (6/96 - 12/97) Release Schedule for validated data sets
* ALL Galileo Cruise Phase (10/89 - 12/95) Data
ALL IMAGING DATA from Orbits 1 through 6
is available via the Planetary Data System (PDS) Imaging Node
For Galileo SSI data, go to URL:
http://www-pdsimage.jpl.nasa.gov/PDS/public/Atlas/Atlas.html
and select the option:
"Galileo SSI REDRs of Earth and the Moon, Venus, Gaspra, Ida, and Jupiter
and its satellites "
The PDS homepage is: http://www-pdsimage.jpl.nasa.gov/PDS/
The PDS offers a simple query interface to access all fully released SSI
data. It allows the user to search by various parameters such as target
name, spacecraft clock, latitude/longitude, filter, phase angle, exposure,
gain, and compression ratio. PDS will continue to expand and improve this
interface which will eventually include a format to select data via a map
interface.
To accomodate the various needs of the scientific community, the archived
files are raw data files which merge the multiple downlinks of data to
provide the best final version of an image. Supporting data such as
calibration files are also available. Such files include dark currents,
radiometric calibrations, blemishes, hot pixels, etc..
Galileo Primary Mission (6/96-12/97)
Solid State Imaging Orbital Data Sets
Public Release Schedule
Orbit 1 (G1) September 06, 1997
Orbit 2 (G2) November 04, 1997
Orbit 3 (C3) December 19, 1997
Orbit 4 (E4) February 20, 1998
Orbit 6 (E6) April 05, 1998
Orbit 7 (G7) May 07, 1998
Orbit 8 (G8) June 25, 1998
Orbit 9 (C9) September 17, 1998
Orbit 10 (C10) November 06, 1998
Orbit 11 (E11) & GEMSchedules will be posted when available.
NASA/JPL's Galileo Project gratefully acknowledges the collaborative efforts
of NASA's Planetary PhotoJournal and the Planetary Data System in making
Galileo mission images and data available to the public and scientific
communities.
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: Sky & Telescope News Bulletin - April 10, 1998
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SKY & TELESCOPE'S WEEKLY NEWS BULLETIN
APRIL 10, 1998
FACE OFF ON MARS
Scientists with NASA's Mars Global Surveyor program have finally settled a
longstanding question about the nature of unusual topographic features in the
red planet's Cydonia region. Noisy, low-resolution Viking images from 1976
showed what looked like a giant mound carved into the shape of a human face.
But new, razor-sharp views from Surveyor, released on April 6th, show a
complex,
hilly formation that has been eroded by Martian winds, frost, and perhaps
surface water. The "Face on Mars" was illusory, though news reports from
earlier this week suggest that some fanatics refuse to give up on the idea
that the alleged face is manmade -- made by little green men, that is.
SIZZLIN' SUNSPOTS
There may be no face on Mars, but there sure are a lot of spots on the Sun's
face. At least four major sunspot groups appeared this week alone. Patrick
McIntosh of Heliosynoptics in Boulder, Colorado, says that if you look at the
Sun's southern hemisphere, you'll think it's solar maximum. The northern
hemisphere looks more typical of solar minimum, though there are a couple of
small spot groups there. In reality, our daytime star has passed the overall
minimum of magnetic activity and is now climbing steeply toward the maximum of
its 11-year cycle, anticipated to occur around the year 2001.
HELLO, TRACE
As the Sun's activity increases, it will come under the scrutiny of a new NASA
satellite. The Transition Region and Coronal Explorer (TRACE) was lofted into
orbit on April 1st by a winged Pegasus rocket dropped from a Lockheed L-1011
aircraft. It will explore the magnetic structures responsible for carrying
energy from the Sun's photosphere, or visible surface, through the thin
chromosphere and out into the wispy corona.
GOOD-BYE, ISO
While the TRACE mission has just begun, that of another astronomy satellite has
come to an end. Europe's Infrared Space Observatory (ISO) ran out of
liquid-helium coolant for its heat-sensitive detectors on April 7th. Originally
expected to last only 18 months, ISO has been in orbit for more than two years.
Highlights of its 26,000 observations include images and spectra of the
star-forming regions in Orion, a survey of interstellar dust clouds, and
studies
of the Small Magellanic Cloud and M33, the large spiral galaxy in Triangulum.
SURF'S UP IN ORION!
Although ISO has ceased taking data, astronomers are still poring over results
gathered earlier. In Astrophysical Journal Letters this month, a team led by
Martin Harwit of Cornell University announces their discovery of a massive
concentration of water vapor in M42, the Orion Nebula. Strong emissions from
steam observed with ISO's long-wavelength spectrometer imply that there's
enough
water in M42 to fill Earth's oceans 60 times over every day! The steam forms in
chemical reactions among the nebula's abundant hydrogen and oxygen molecules,
energized by the ultraviolet light of hot, young stars.
GALILEO'S GYRATIONS
There's yet another spacecraft in the news this week. The Galileo Jupiter
orbiter continues its extended mission, the focus of which is the enigmatic ice
moon Europa. The last Europa flyby was on March 29th, and the next comes on May
31st. Flight controllers are practicing using stellar navigation to orient the
spacecraft properly, because one of its stabilizing gyros is showing signs of
radiation damage from the harsh Jovian environment.
URANUS' NEW MOONS RECOVERED
Now that the distant planet Uranus has emerged from the solar glare,
astronomers
have recovered the two tiny moons discovered last September. Curiously, one was
a half arcminute off its predicted position, while the other was fully 3
arcminutes off. As reported in IAU Circulars 6869 and 6870, the new
observations
indicate that the moon known as S/1997 U1 orbits Uranus in a more circular path
than originally thought, while its counterpart, S/1997 U2 moves in a much more
elongated orbit. With the orbits now well defined, it has been possible to
confirm that a tentative report of a possible Uranian satellite in 1984 was, in
fact, a prediscovery observation of S/1997 U1.
THIS WEEK'S "SKY AT A GLANCE"
Some daily events in the changing sky, from the editors of SKY & TELESCOPE.
APRIL 12 -- SUNDAY
* Well to the upper right of the Moon tonight is the blue-white star Spica.
About twice as far to the Moon's upper left is brighter Arcturus, pale
yellow-orange.
APRIL 13 -- MONDAY
* Saturn is in conjunction with the Sun.
APRIL 14 -- TUESDAY
* Some doorstep astronomy: Face southwest right after dark; the brilliant
star rather low is Sirius. To its right, by about two fist-widths at arm's
length, is the horizontal row of three fainter stars forming Orion's Belt.
* The red variable star T Camelopardalis should be near maximum light (8th
magnitude) around this date.
APRIL 15 -- WEDNESDAY
* The orange star Antares rises to the lower right of the waning gibbous
Moon around 11 tonight.
APRIL 16 -- THURSDAY
* As dawn begins to break on Friday morning, Venus appears only 1/3 degree
from the 4th-magnitude orange star Lambda Aquarii. Have a look with binoculars.
APRIL 17 -- FRIDAY
* Some doorstep astronomy: Face due south soon after dark and look high up.
The brightest star there is Regulus in the constellation Leo.
APRIL 18 -- SATURDAY
* This morning and tomorrow morning, Jupiter is only 0.1 degree from the
4.4-magnitude orange star Phi Aquarii.
============================
THIS WEEK'S PLANET ROUNDUP
============================
MERCURY, MARS, and SATURN are hidden in the glare of the Sun.
VENUS shines low in the east-southeast during dawn.
JUPITER is to the lower left of Venus, closing in on it daily. They're 9
degrees apart on the morning of April 12th, and 4 degrees apart on the 18th.
(By comparison, your fist held at arm's length appears about 10 degrees wide.)
URANUS and NEPTUNE, magnitudes 6 and 8, respectively, are in Capricornus low
in the southeast just before dawn.
PLUTO, magnitude 13.8, is near the Ophiuchus-Scorpius border. It's well up
in the southeast by about 1 a.m.
(All descriptions that relate to the horizon or zenith are written for the
world's midnorthern latitudes. Descriptions that also depend on longitude
are for North America. Eastern Daylight Time, EDT, equals Universal Time
minus 4 hours.)
Copyright 1998 Sky Publishing Corporation. S&T's Weekly News Bulletin and
Sky at a Glance stargazing calendar are provided as a service to the
astronomical community by the editors of SKY & TELESCOPE magazine.
Widespread electronic distribution is encouraged as long as these paragraphs
are included. But the text of the bulletin and calendar may not be
published in any other form without permission from Sky Publishing (contact
permissions@skypub.com or phone 617-864-7360). Illustrated versions,
including active links to related Internet resources, are available via SKY
Online on the World Wide Web at http://www.skypub.com/.
In response to numerous requests, and in cooperation with the Astronomical
League and the American Association of Amateur Astronomers, S&T's Weekly New
Bulletin and Sky at a Glance are available via electronic mailing list too.
For a free subscription, send e-mail to skyline@gs1.revnet.com and put the
word "join" on the first line of the body of the message. To unsubscribe,
send e-mail to skyline@gs1.revnet.com and put the word "unjoin" on the first
line of the body of the message.
SKY & TELESCOPE, the Essential Magazine of Astronomy, is read by more than
200,000 enthusiasts each month. It is available on newsstands worldwide.
For subscription information, or for a free copy of our catalog of fine
astronomy books and products, please contact Sky Publishing Corp., P.O.
Box 9111, Belmont, MA 02178-9111, U.S.A. Phone: 800-253-0245 (U.S. and
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custserv@skypub.com. SKY Online: http://www.skypub.com/. Clear skies!
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: NASA Finds Problems In EOSDIS Flight Operations Software Development
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David E. Steitz
Headquarters, Washington, DC April 10, 1998
(Phone: 202/358-1730)
Allen Kenitzer
Goddard Space Flight Center, Greenbelt, MD
(Phone: 301/286-2806)
RELEASE: 98-60
NASA FINDS PROBLEMS IN EOSDIS FLIGHT
OPERATIONS SOFTWARE DEVELOPMENT
NASA has found software performance problems with ground
system software required to control, monitor and schedule science
activities on the Earth Observing System (EOS) series of
spacecraft.
Officials believe these problems will delay the software
which will impact the launch date for the Earth Observing
Spacecraft AM-1. The launch, originally planned for late June
1998, from Vandenberg Air Force Base, CA, will be delayed at least
until the end of the year.
The Ground Control Software, called the "Flight Operations
Segment" (FOS) software, is part of the Earth Observing System
Data and Information System (EOSDIS), the ground system
responsible for spacecraft control, data acquisition, and science
information processing and distribution for NASA's Earth Science
enterprise, including the EOS flight missions.
The problem is with the EOSDIS control center system FOS
software that supports the command and control of spacecraft and
instruments, the monitoring of spacecraft and instrument health
and safety, the planning and scheduling of instrument operations,
and the analysis of spacecraft trends and anomalies.
What was supposed to have been the final version of the
software was delivered to NASA by Lockheed Martin on March 31, to
support integrated simulations with the EOS AM-1 spacecraft.
Testing of this software delivery revealed significant performance
problems. Program managers expect it to take several weeks to
clearly understand whether correcting the current software or
taking other measures is the best approach.
"We're concurrently looking at commercial off-the-shelf
technology that was not available when this software system
initially was designed," said Arthur "Rick" Obenschain, project
manager for EOSDIS at NASA's Goddard Space Flight Center,
Greenbelt, MD. "If for some reason the current software problems
cannot be fixed, we have a backup plan."
Prior to the March 31 delivery, there were three previous
incremental deliveries of the software in August 1997, December
1997 and February 1998. Previous versions of the software
successfully demonstrated real-time commanding functions with the
AM-1 spacecraft. In the new version, however, a number of
problems identified in the previous software deliveries were not
corrected as expected, and significant problems were found in the
new capabilities. Problems include unacceptable response time in
developing spacecraft schedules, poor performance in analyzing
spacecraft status and trends from telemetry data, and improper
implementation of decision rules in the control language used by
the flight team to automate operations.
Government/contractor teams have been formed to evaluate
options for correcting these problems to minimize impact on the
AM-1 launch. A recovery plan is being developed and will be
reviewed during the last week of April.
The FOS is being developed by Lockheed Martin under
subcontract to Raytheon Information Systems Company under the
EOSDIS Core System contract. The Flight Operations Segment of the
EOSDIS software has cost $27.5 million as of February 1998.
THE EOSDIS and EOS AM-1 are part of NASA's Earth Science
enterprise, a
long-term research program designed to study Earth's land, oceans,
atmosphere, ice and life as a total integrated system. Goddard
manages the development of EOSDIS and EOS AM-1 for NASA's Office
of Earth Science, Washington, DC.
-end-
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: Mars Global Surveyor Update - April 10, 1998
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MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov
Mars Global Surveyor Mission Status
April 10, 1998
The Mars Global Surveyor operations team is gearing up to
begin imaging a second set of specifically targeted geologic
features on Mars, after completing the first set of images last
week and successfully capturing the so-called "Face on Mars."
At the direction of NASA Administrator Daniel Goldin, the
flight team has developed a schedule of new targets. On Tuesday,
April 14, Global Surveyor will image a second portion of the
Cydonia region known as "The City." This area of Cydonia
contains geological features that have been referred to as
"mounds," a "city square," "pyramids" and "the fortress." The
spacecraft's high-resolution camera will use the "city square"
portion of this geologic formation as the target point.
The image will be posted on JPL's Mars news site at
http://www.jpl.nasa.gov/marsnews, on the Mars Global Surveyor
project home page at http://mars.jpl.nasa.gov, and on NASA's
Planetary Photojournal site at http://photojournal.jpl.nasa.gov
as soon as it is available. This is expected to be by about mid-
evening Pacific time on Tuesday, April 14.
Last week's attempts to image the landing sites of the
Viking 1, Viking 2 and Mars Pathfinder landers were unsuccessful.
Global Surveyor will make new attempts to image the Viking sites
on two consecutive orbits on Sunday, April 12. On Monday, April
13, the spacecraft will image the Mars Pathfinder landing site,
using refined coordinates obtained during the first attempt.
Winter weather in the northern hemisphere of Mars was a
significant factor in preventing a view of the landing sites
during the first series of attempts. The site of the Viking
Lander 1 in Chryse Planitia, for instance, was covered with a
thick cloud layer, which reduced but did not eliminate surface
visibility. However, data showed that the spacecraft's pointing
was off just enough to miss that target.
The spacecraft was able to target the Viking 2 lander site
in Utopia Planitia, which is farther north and on the other side
of Mars from Viking 1. However, this area was heavily overcast
with clouds and haze which reduced surface visibility by 70 to 80
percent and rendered the image unusable. The spacecraft missed
the Mars Pathfinder site due to the inaccuracy of landing site
coordinates.
The project team estimates that Global Surveyor has about a
30 to 50 percent of imaging each target on a given attempt, due
to navigation uncertainties and spacecraft performance.
A third and final set of high-resolution imaging of the
Viking, Pathfinder and Cydonia regions will be attempted on April
21-23.
#####
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: Mars Global Surveyor Update #2 - April 10, 1998
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From The Mars Global Surveyer home page:
http://mars.jpl.nasa.gov/mgs/target/update4-10.html
PLANS FOR SECOND CLUSTER OF TARGETED IMAGING
10-APR-98 5:00 PM PDT
The Mars Surveyor Operations Project is proceeding with the implementation
of its second cluster of targeted imaging at Mars. This cluster will target
the two Viking Lander sites, an refined Mars Pathfinder landing site, and,
because of the previous successful imaging of the "Face on Mars", a
different area of the Cydonia region will be targeted.
On Sunday, April 12th, at 8:22 AM PDT and at 8:01 PM PDT, MGS will again
attempt to image the sites of the Viking Landers on two consecutive orbits.
On Monday, April 13th, at 7:40 AM PDT, MGS will again attempt to image the
site of the Mars Pathfinder landing. The coordinates of the site have been
refined since the first imaging attempt.
On Tuesday morning, April 14th, at 6:56 AM PDT, MGS will again image a
portion of the Cydonia region. Because the image of the "Face" was
successful in the last attempt, the target area will be shifted slightly to
the southwest of the "Face" to capture an image of the features known as
"The City". This area contains features identified as "mounds", "city
square", "pyramid" and the "fortress". The "city square" will the target
point.
The same probabilities of success of 30% to 50% will apply to these attempts
based on navigation uncertainties and spacecraft performance. Experience
with the first cluster of targeted images has shown that winter weather in
the northern hemisphere of Mars at this time causes hazy, surface frost and
heavy cloud cover to be significant factors in the success of seeing the
targets clearly. The weather effects are not included in the probability of
success estimates.
Results of the Cydonia imaging will be posted on the Internet, in the same
manner as in the first observation attempt, at approximately mid-evening
Pacific Time on Tuesday, April 14th. If the landers are within the resulting
images and can be identified, the image(s) containing it (them) will be
released.
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: This Week On Galileo - April 13-19, 1998
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THIS WEEK ON GALILEO
April 13-19, 1998
Processing and transmission to Earth of pictures and other science
information, a process also known as playback, is the sole order of business
this week on Galileo. The data was gathered and stored on the spacecraft's
onboard tape recorder during the last few days of March as the spacecraft
flew through the Jupiter system and within 1,645 kilometers (1022 miles) of
the surface of Jupiter's moon Europa.
Most of the data return this week was obtained by the spacecraft camera, or
Solid State Imaging (SSI) subsystem, during the close flyby of Europa. Among
the pictures returned this week we find a couple containing the Mannann'an
crater. Taken from slightly different angles, this pair of images will be
combined to form a stereo image of the region. A similar pair of pictures
containing a region of dark spots on Europa is also returned this week. This
pair will also be combined to form a stereo image of the region. Regional
coverage of this same dark spot area was obtained in November 1997. Another
SSI observation provides photometric information describing Europa's
surface. These photometric measurements will tell us how intensely light is
reflected from the surface and provide additional information on its makeup.
Finally, a picture of a region of triple-bands is returned. These
triple-band features are believed to be formed when Europa's surface cracks,
material upwells from below the surface and spills to both sides of the
central crack. They are considered evidence for the possible existence of a
sub-surface ocean or, at the least, soft ice.
Sprinkled throughout the week, similar to last week's playback schedule, is
information from the fields and particles instruments describing the
interaction of Jupiter's magnetosphere with Europa. Remember that Jupiter's
magnetosphere is that region of space where Jupiter's magnetic and electric
fields dominate those fields generated by the solar wind. The charged
particles that make up the magnetosphere co-rotate with Jupiter, at a rate
of about 1 revolution every 10 hours, and get disturbed as they sweep past
each of the satellites in orbit around Jupiter. Each new bit of data
describing this interaction will help scientists understand the phenomena at
work.
For more information on the Galileo spacecraft and its mission to Jupiter,
please visit the Galileo home page:
http://www.jpl.nasa.gov/galileo/
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=SANA=
Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: Wapor Vapor Discovered In Orion
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News Service
Cornell University
Astronomers discover a huge chemical "factory" in interstellar space,
suggesting origin of water in solar system
Contact: David Brand
Office: (607) 255-3651
E-Mail: deb27@cornell.edu
FOR RELEASE: APRIL 9, 1998
ITHACA, N.Y. -- A team of U.S. astronomers, led by Cornell University
astrophysicist Martin Harwit, has discovered a massive concentration of
water vapor within a cloud of interstellar gas close to the Orion nebula.
The amount of water measured is so high -- enough to fill the Earth's oceans
60 times a day -- that the researchers believe it provides an important clue
to the origin of water in the solar system.
The amount of water vapor measured in Orion is 20 times larger than that
observed in other interstellar gas clouds in our galaxy, the Milky Way. The
discovery was made within the Orion molecular cloud, a giant interstellar
gas cloud, a trillion miles across, composed primarily of hydrogen
molecules.
The measurements were made with the long-wavelength spectrometer aboard the
Infrared Space Observatory (ISO) launched in November 1995 by the European
Space Agency with the participation of NASA. The observations were made in
October 1997 and are reported today (April 20) in the Astrophysical Journal
Letters.
Looking in the far-infrared region of the electromagnetic spectrum, the
astronomers observed the characteristic signature of emission by water
vapor. "The interstellar gas cloud that we observed is being pummeled by
shock waves that compress and heat the gas," says Harwit, who is a Cornell
professor emeritus, an ISO mission scientist and lead author on the research
report. "These shock waves are the result of the violent early stages of
star birth in which a young star spews out gas that slams into its
surroundings at high speed. The heated water vapor that we observed is the
result of that collision," he says.
Such a high concentration of water in Orion's giant gas cloud, which swirls
around millions of stars along our spiral arm of the Milky Way, 1,500 light
years from the sun, could have implications for the origin of water in the
solar system, says ISO team member David Neufeld, professor of physics and
astronomy at Johns Hopkins University. "The interstellar gas cloud that we
observed in Orion seems to be a huge chemical factory generating enough
water molecules in a single day to fill the Earth's oceans 60 times over."
Eventually, he says, the water vapor will freeze, becoming small ice
particles. Similar ice particles are thought to have been present within the
gas cloud from which the solar system originally formed. "It seems quite
plausible that much of the water in the solar system was originally produced
in a giant water vapor factory like the one we have observed in Orion,"
Neufeld says.
Cornell's Harwit speculates that the shock waves observed in the Orion gas
cloud could be a cause as well as the result of star birth. The shock waves
might also trigger the formation of additional stars and planets as they
compress the gas cloud -- if the heat can be radiated away, says Harwit.
"Water vapor is a particularly efficient radiator at far-infrared
wavelengths and plays a critical role in cooling the gas and facilitating
star formation," he notes.
The concentration of water vapor measured by the team was about one part in
2,000 by volume. The new observations confirm predictions by astrophysicists
over the past 25 years that whenever the temperature exceeds 200 degrees
Fahrenheit, chemical reactions will convert most of the oxygen atoms in
interstellar gas into water.
"An enhanced concentrator of water is precisely what we expected in this gas
cloud," says team member Gary Melnick of the Harvard-Smithsonian Center for
Astrophysics. He adds that the strength of the water radiation detected from
Orion was in perfect agreement with theoretical predictions published in the
doctoral thesis of team member Michael Kaufman, a former Johns Hopkins
graduate student now at NASA's Ames Research Center.
Panels showing two examples of measurements carried out on board the ISO,
together with an image of the Orion nebula taken with the Wide Field
Planetary Camera 2 on NASA's Hubble Space Telescope, can be seen on the
World Wide Web at http://www.pha.jhu.edu/~neufeld/orionwater.html.
- 30 -
PHOTO CAPTION: [http://www.pha.jhu.edu/~neufeld/orionwater.html]
WATER VAPOR IN ORION
The presence of water vapor near the Orion nebula is indicated by an increased
flux of infrared radiation at specific wavelengths, which provides a unique
fingerprint of water molecules. The strength of the observed radiation tells
astrophysicists the concentration of water vapor that is present.
The panels at the upper left and lower right show two examples of flux
measurements carried out by the Long Wavelength Spectrometer (LWS) on board the
European Space Agency's Infrared Space Observatory (ISO). They indicate the
presence of a large concentration of water vapor.
The central panel is an image of the Orion nebula taken with the Wide Field
Planetary Camera 2 (WFPC2) on NASA's Hubble Space Telescope (HST) and shows the
region of space where the water vapor was detected.
Hа сегодня все, пока!
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Дата: 13 апреля 1998 (1998-04-13)
От: Alexander Bondugin
Тема: FUNDAMENTAL DISCOVERY IN THE GRAVITATION
Привет всем!
Вот, свалилось из Internet...
Aleksandr Timofeev, Valdimir Timofeev, Love Timofeeva
The reliable experimentally received mass values are available
for the following planets:
Integer
Planet Notations Mass | Ratio Experemental number
of mass value | value commensur-
value | ability
|
Jupiter MJU or 1 317.735 |(MJU+MSA)/(MUR+MNE)= 12.995971 ~ 13
Saturn MSA or 2 95.147 | MJU/(MUR+MNE) = 10.001011 ~ 10
Neptune MNE or 3 17.23 | MSA/(MUR+MNE) = 2.994869 ~ 3
Uranus MUR or 4 14.54 | (MJU+MSA)/MNE = 23.9630 ~ 24
Earth MTE or 5 1.000 | MUR/(MTE+MVE) = 8.011019 ~ 8
Venus MVE or 6 0.815 | (MNE+MUR)/MVE = 38.9816 ~ 39
Mars MMA or 7 0.108 | (MTE+MVE)/MME = 33.0000 ~ 33
Mercury MME or 8 0.055 | MVE/(MMA+MME) = 5.0000 ~ 5
Hense it follows - the chain of discrete commensurabilities
between values of planetary masses in Solar system.
10
I<----------->|
I 13 |
I<==============>I
I | I
? 39 I | I
|<--------------------->I 33 |<---------------->I 24 | I
| |<------------------>I |<----------------->I
| | I ? | | I 5 | | I 8 | | I 3 | | I
| | I<====>| | I<====>| | I<====>| | I<====>| | I
| | I | | I | | I | | I | | I
10 9 I 8 7 I 6 5 I 4 3 I 2 1 I
I | | I | | I | | I | | I
I Mercury MarsI Venus EarthI Uran NepI Saturn JupiterI
I I I I I
10+9 8+7 6+5 4+3 2+1
ln(mass)
- - ---------------------------------------------------------------->
The following disignations are used:
MSA+MJU <--> 2+1 ; MUR+MNE <--> 4+3 ;
MVE+MTE <--> 6+5 ; MME+MMA <--> 8+7 ;
MJU <--> 1 ; MSA <--> 2 ; MNE <--> 3 ; MUR <--> 4 ;
MTE <--> 5 ; MVE <--> 6 ; MMA <--> 7 ; MME <--> 8
5 10
Direct relations - <====> ; Reverse relations - <----------->
The chain of relations of body couples mass values is of
periodic type. It has a mirror reflection for direct and reverse
relations. (A strong association with strap filters made of
concentrated elements appears. This association is supported by
the existence of self-coordination elements at the beginning
of a chain).
The chain of direct and reverse relations have not the breaks
in the symmetry.
The chain of direct and reverse relations for values of mass
show that there exists mechanisms inside of gravitation field that ones
are providing the dynamic maintenance of corresponding correlations for
values of mass and which are responsible for stability and stationarity
of the Solar system.
The chains of relations of body mass values embraces whole
Universe (Gravitation chemistry).
This is a part of report "Future of the Science" wrote
by P. L. Kapica (he is disciple of Rutherford) in 1959:
Scientific discoveries of the future.
Now I want to stay on those areas of a science, which, as it is
possible to assume, anew will arise hereafter. Here prognosises can be
done, proceeding of different premises. I assume it to make on a
principle of an extrapolation and consequently I shall begin
consideration from an evaluation of an amount of new natural phenomena,
which were open by a science within past years. I want to be stipulated,
that expression " the new phenomenon " I enclose to such physical
phenomenon, which cannot completely be predicted, to explain because of
already of being available theoretical concepts, and consequently they
open new areas of researches. To make an offered extrapolation clearer,
I shall name the main, main new phenomena in physics, which were open
for the last hundred fifty years.
First of all I want to name discovery Galvany in 1789. An electric
current, which, certainly, did not follow in any way from existing then
theoretical concepts about a nature of an electricity, in main created
by Franklin.
The following discovery approaching under the given definition, is
a discovery by an Oersted in 1820 of influence of an electric current on
magnetic arrow. From our point of view; from the point of view of made
later discovery Faradey of a magnetic induction is not new, as the
magnetic induction on the entity represents the phenomenon, return open
by an Oersted and, thus, in that time it could be foreseed. The works of
an Oersted and Faradey have reduced in the law Lenc, to creation of the
equations of the Maxwell and to a number of other fundamental
conclusions, but all of them were development of main discovery of an
Oersted to predict which on a theoretical basis it was completely
impossible.
The following example of the new phenomenon - external photoeffect
open in 1887. By a Hertz (all of us, certainly, are greater honour of a
Hertz for detection by him of electromagnetic waves). This phenomenon also
could not be foreseed theoretically. Because of studies of a photoeffect
of years a thirty after has introduced famous of the equations by
Einstein, which has determined a quantum nature this phenomenon.
Principle of indeterminacy and quantum theory were predetermined by
discovery of a photoeffect, and all remarkable scientific development of
this phenomenon make only further methodical work.
Then it is possible to name discovery Becquerel in 1896 of a
radio-activity (which also it was impossible to foresee because of
existing then theories), nuclear physics, which has put in pawn
beginnings.
Further detection Thomson of an electron too can be considered
as discovery of the new phenomenon which has put in pawn the basis of a
modern electronics engineering. Experiment Michelson and Morley, as it
has given an outcome, which could not be foreseed theoretically, too it
is possible to name as discovery of the new phenomena installing main
principles of a relativity theory. It was impossible to foresee
discovery Hess in 1919 of space rays. I believe, that it is necessary to
mark as new also discovery of division of uranium made Meitner and Gan.
What is typical all former discoveries? First of all, the value
them was realized completely only in 20-30 years, when became clear, that
they cannot be explained scientific sights of that time, and
consequently under their influence varied and the new directions in the
main theoretical concepts developed.
Whether the similar discoveries hereafter are possible?
Whether all physical discoveries in a nature are settled now? Whether
there are still such fundamental new phenomena in a nature, which wait
for the discovery?
If to construct a curve and on a horizontal axes to postpone time, and
on vertical - number of discoveries and if honesty to consider this
curve of discoveries, we can see, that she has not the tendency to drop
to zero. Therefore, to extrapolate this curve, we can see, that in the
near future we shall witness not yet one of the not less important and
"new" discovery, than just listed. They will allow even deeper to
understand a nature, enclosing us, and the new possibilities for growth
our of culture will put at disposal of the people.
===========================================
Usually it is possible to see, that the people are inclined to
consider, that they already know about a nature everything, that it is
possible to know. So was always. It is enough to esteem transactionses
of the contemporaries of a Newton to see, as then many considered, that
with discovery of the classical laws of a mechanics the knowledge of a
dead nature is completed. Though it frequently also contradicts our
subjective sensation, but we should not henceforth do same an error - to
consider, that hereafter new discoveries will not be make.
===========================================
Probably, you ask me, what it there will be discoveries.
If I could them predict, thereby they would not become
unexpected and new. ...
See http://solar.cini.utk.edu/~russeds/unknown/astrochem/
for more information about this work - "Gravity mass - some properties"
Regards,
Aleksandr
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