07 - Mercury
at inferior conjunction with the Sun
at 15h UT.
0000Mercury
passes into the morning sky (not visible).
08 - Moon
near Mars at 1h UT (evening sky). Mag.
+1.5.
19 - Venus
at superior conjunction with the Sun
at 4h UT.
0000Passes
into the evening sky (not visible).
19 - Moon
near Saturn at 7h UT (evening sky).
Mag. +0.7.
18 - Full Moon at 17:30 UT.
20 - Moon near Jupiter at 14h
UT (morning sky). Mag. -2.7. Jupiter displays
the
0000largest
and most detailed planetary disk of all the
planets. Even a small telescope
0000will
reveal Jupiter's cloud bands and its four largest
moons known as the Galilean
0000moons
(discovered by Galileo in 1610). Jupiter has
a total of 63 moons.
20 - Pluto at opposition at
16h UT. Mag. 14. Requires at least a 10-inch
telescope and
0000a
very dark sky to view.
20 - June solstice at 23:59
UT. The time when the Sun reaches the point
farthest north
0000of
the celestial equator marking the start of summer
in the Northern Hemisphere
000
and winter in the Southern Hemisphere.
00 0 0
0 0 0//
Get the complete calendar version
at skymaps.com
7 -
The
Outrageous Tales of a Space Shuttle Astronaut
- On February 1, 1978, the first group of space shuttle
astronauts, twenty-nine men and six women, were introduced
to the world. Among them would be history makers, including
the first American woman and the first African American
in space. This assembly of astronauts would carry NASA
through the most tumultuous years of the space shuttle
program. Four would die on Challenger. Mullane vividly
portrays every aspect of the astronaut experience --
from telling a female technician which urine-collection
condom size is a fit; to walking along a Florida beach
in a last, tearful goodbye with a spouse; to a wild,
intoxicating, terrifying ride into space; to hearing
"Taps" played over a friend's grave. Mullane is brutally
honest in his criticism of a NASA leadership whose bungling
would precipitate the Challenger disaster.
Friday, May 19, 2006
Three Neptune-sized Planets Around a Nearby Star Discovered
A new planetary system was discovered by Eropean astronomers by using the ultra-precise HARPS spectrograph on ESO's 3.6-m telescope at La Silla (Chile). Three Neptune-size planets were detected orbiting its parent star, HD 69830. The discovery also reveals the planetary system enriched with asteroid belt. The parent star is located just 41 light-years away towards the constellation of Puppis (the Stern), it is, with a visual magnitude of 5.95, just visible with the unaided eye.
The newly found planets have minimum masses between 10 and 18 times the mass of the Earth. Extensive theoretical simulations favour an essentially rocky composition for the inner planet, and a rocky/gas structure for the middle one. The outer planet has probably accreted some ice during its formation, and is likely to be made of a rocky/ icy core surrounded by a quite massive envelope. Further calculations have also shown that the system is in a dynamically stable configuration.
The outer planet also appears to be located near the inner edge of the habitable zone, where liquid water can exist at the surface of rocky/icy bodies. Although this planet is probably not Earth-like due to its heavy mass, its discovery opens the way to exciting perspectives.
NASA's Spitzer Space Telescope has snapped a picture of the bits and pieces making up Comet 73P/Schwassman-Wachmann 3, which is continuing to break apart on its periodic journey around the sun. The new infrared view shows several chunks of the comet riding along its own dusty trail of crumbs.
Comet 73P/Schwassman-Wachmann 3 consists of a collection of fragments that file along like ducks in a row around the sun every 5.4 years. This year, the bunch will pass by Earth beginning on May 12 before swinging by the sun on June 6. The fragments won't get too close to Earth, about 7.3 million miles, or 30 times the distance between Earth and the moon, but they should be visible through binoculars in the countryside night skies.
During the past six weeks, amateur and professional astronomers have been watching the comet fall apart before their telescopes' eyes. Spitzer viewed the broken comet from its quiet perch up in space May 4 to May 6, covering a portion of the sky that allowed it to spot 45 of the 58 known fragments.
Comet 73P/Schwassman-Wachmann 3 should be dimly visible through binoculars on a clear night between the Cygnus and Pegasus constellations from May 12 to May 28.
We all know Earth rotates every 24 hours, but scientists have long had difficulty pinpointing how long the day is on Saturn. The magnetometer onboard the Cassini spacecraft has, for the first time ever, measured a periodic signal in Saturn's magnetic field, key information to finally understanding the length of a Saturn day and the evolution of this gaseous planet.
The latest research suggests a Saturn day is 10 hours, 47 minutes, 6 seconds (plus or minus 40 seconds). That is 8 minutes slower than NASA Voyager results from the early 1980s, and slower than previous estimates from another Cassini instrument. The magnetometer results provide the best estimate of the Saturn day to date, because it can see deep inside Saturn. These Cassini results are in the May 4 issue of the journal Nature.
The
Oort cloud, is a postulated spherical cloud
of comets situated about 50,000 to 100,000 AU from
the Sun. This is approximately 1000 times the distance
from the Sun to Pluto or roughly one light year, almost
a quarter of the distance from the Sun to Proxima
Centauri, the star nearest the Sun. The Oort cloud
would have its inner disk at the ecliptic from the
Kuiper belt. Although no direct observations have
been made of such a cloud, it is believed to be the
source of most or all comets entering the inner solar
system (some short-period comets may come from the
Kuiper belt), based on observations of the orbits
of comets. Source: Wikipedia
