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2012
Explosion on Jupiter, 10-SEP-2012
New Horizons Mission: Kuiper Belt Fly-Through
Animation by Alex Parker:
Fly with the New Horizons spacecraft as it cruises by dozens of newly-discovered Kuiper Belt Objects (KBOs) near its trajectory. These objects were found by our survey team (gray points) as well as by members of the public through Ice Hunters (purple points) during a search - still under way - to find a KBO for New Horizons to approach close enough to take detailed images and measurements of its surface. See below for details.
Animation concept and rendering by Alex Harrison Parker, Harvard-Smithsonian Center for Astrophysics.
Huge solar particle event, at least 10 times larger than any in modern times
Carbon-14 evidence was found in tree rings that suggests a big radiation dose came down around 775 A.D., suggesting a huge solar particle event, at least 10 times larger than any in modern times
Data From NASA's Voyager 1 Point to Interstellar Future
http://www.jpl.nasa.gov/news/news.cfm?release=2012-177
June 14, 2012
Data from NASA's Voyager 1 spacecraft indicate that the venerable deep-space explorer has encountered a region in space where the intensity of charged particles from beyond our solar system has markedly increased. Voyager scientists looking at this rapid rise draw closer to an inevitable but historic conclusion - that humanity's first emissary to interstellar space is on the edge of our solar system.
"The laws of physics say that someday Voyager will become the first human-made object to enter interstellar space, but we still do not know exactly when that someday will be," said Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena. "The latest data indicate that we are clearly in a new region where things are changing more quickly. It is very exciting. We are approaching the solar system's frontier."
The data making the 16-hour-38 minute, 11.1-billion-mile (17.8-billion-kilometer), journey from Voyager 1 to antennas of NASA's Deep Space Network on Earth detail the number of charged particles measured by the two High Energy telescopes aboard the 34-year-old spacecraft. These energetic particles were generated when stars in our cosmic neighborhood went supernova.
Oxygen forms on icy moons in a strong trapped-radiation and plasma
Dione, one of Saturn’s icy moons, has a weak exosphere that includes molecules of oxygen, according to new findings from the Cassini-Huygens mission.
The international mission made the discovery using combined data from the Cassini Plasma Spectrometer (CAPS), which includes a sensor designed and built at the University College London’s (UCL) Mullard Space Science Laboratory.
Dione joins Rhea and the main rings in Saturn's system in having an oxygen-rich exosphere, as well as Jupiter’s moons Ganymede, Europa, and Callisto — the target for the European Space Agency’s (ESA) proposed Jupiter Icy Moons Explorer (JUICE) mission for launch in 2022 ( http://www.esa.int/esaCP/SEM9I4QWJ1H_index_0.html ).
“It now looks like oxygen production is a universal process wherever an icy moon is bathed in a strong trapped-radiation and plasma environment,” said Andrew Coates from UCL. “Energetic particles hit the icy surface, the hydrogen is lost, and molecular oxygen remains as an exosphere. We now know that this happens at Saturn's moons as well as Jupiter's, and it may well occur in extrasolar planetary systems, too.”
Science fiction has turned into reality:
PLANET THAT ORBITS AROUND TWO STARS
A planet with two suns may be a familiar sight to fans of the Star Wars film series, but not, until now, to scientists. A team of researchers, including Carnegie's Alan Boss, has discovered a planet that orbits around a pair of stars.
This is the first instance of astronomers finding direct evidence of a so-called circum-binary planet. A few other planets have been suspected of orbiting around both members of a dual-star system, but the transits of the circumbinary planet have never been detected previously.
The team, led by Laurance Doyle from the Carl Sagan Center for the Study of Life in the Universe at the SETI Institute in Mountain View, California, used photometric data from NASA’s Kepler space telescope, which monitors the brightness of 155,000 stars.
In addition to the usual two eclipses (primary and secondary ones), they found also tertiary and quaternary eclipses, indicating a presence of a third eclipsing body.
An Almost Earth Exoplanet - Kepler 22b
http://www.nasa.gov/mission_pages/kepler/news/kepscicon-briefing.html 12-MAY-2011
NASA's Kepler mission has confirmed its first planet in the "habitable zone," the region where liquid water could exist on a planet’s surface. Kepler also has discovered more than 1,000 new planet candidates, nearly doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host star. Candidates require follow-up observations to verify they are actual planets.
The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our Sun. The planet is about 2.4 times the radius of Earth. Scientists don't yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets.
Two Other Circum-Binary Exoplanets - Kepler-34b and Kepler 35b
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10768.htm
Nature (11-JAN-2012) reports "Most Sun-like stars in the Galaxy reside in gravitationally bound pairs of stars (binaries). Although long anticipated, the existence of a ‘circumbinary planet’ orbiting such a pair of normal stars was not definitively established until the discovery of the planet transiting (that is, passing in front of) Kepler-16. Questions remained, however, about the prevalence of circumbinary planets and their range of orbital and physical properties. Here we report two additional transiting circumbinary planets: Kepler-34 (AB)b and Kepler-35 (AB)b, referred to here as Kepler-34 b and Kepler-35 b, respectively. Each is a low-density gas-giant planet on an orbit closely aligned with that of its parent stars. Kepler-34 b orbits two Sun-like stars every 289 days, whereas Kepler-35 b orbits a pair of smaller stars (89% and 81% of the Sun’s mass) every 131 days. The planets experience large multi-periodic variations in incident stellar radiation arising from the orbital motion of the stars. The observed rate of circumbinary planets in our sample implies that more than ~1% of close binary stars have giant planets in nearly coplanar orbits, yielding a Galactic population of at least several million."
The Pluto Case
Pluto has long time been considered the last planet of our solar system, fitting, however no of the two basic planet categories: Earth-like (terrestrial) and Jupiter-like (Jovian), so Pluto has been an extra planet representing itself: During closest approach to Sun, an eclipsing with a background star, a lot information has been obtained about Pluto: its more exact diameter, and absorption spectral analysis of the released gases - very thin atmosphere. Then, the eclipsing with its moon Charon provided even more accurate diameters of the both objects, Charon's orbital period synchronized with Pluto's rotational period (tidal locking), masses and densities of the both objects.
Pluto shadowed a star
http://www.nasa.gov/mission_pages/SOFIA/11-21.html
23-JUN-2011, the most unique study of the Pluto's transit over a distant star succeeded from a highly modified Boeing 747SP aircraft. It carries a telescope with a 100-inch (2.5-meter) mirror that conducts astronomy research not possible with ground-based telescopes. By operating in the stratosphere at altitudes up to about14 km, SOFIA makes observations above the water vapor in Earth's lower atmosphere. The study contributes to our knowledge of the Pluto's atmosphere structure.
NEW HORIZONS
http://pluto.jhuapl.edu/mission/calculator.php
New Horizons is a space mission to the solar system edge, specifically the Pluto System and the Kuiper Belt. The National Academy of Sciences, U. S. A., has ranked the exploration of the highest priority for solar system exploration. Pluto and its largest moon Charon belong to a third category known as "ice dwarfs". They have solid surfaces but, unlike the terrestrial planets, a significant portion of their mass is icy material. In 2006, using Hubble Space Telescope images, New Horizons team members discovered two previously unknown moons of Pluto, Nix and Hydra (see above).
Where is New Horizons now?
http://pluto.jhuapl.edu/mission/whereis_nh.php#
Solar System Distances Calculator: http://pluto.jhuapl.edu/mission/calculator.php
As the fastest object created by man, moving about 1 million km/day, it is 22.44 AU distant from Earth already today, 18-JUN-2012, 00:00h UTC (see below). Please note that the time for a command signal to and back from the spacecraft (signal confirmation), sent per microvawes traveling with the speed of light takes almost six and half hours (round-trip light time, at the bottom of the graphic).
Patsy Tombaugh, widow of the Pluto's discoverer Clyde Tombaugh, passed Jan 12 at age 99
http://pluto.jhuapl.edu/news_center/news/20120116.php
It was January 2006, just days before the New Horizons spacecraft lifted off from Cape Canaveral Air Force Station, Florida. A reporter asked Patsy Tombaugh, widow of Pluto’s discoverer, Clyde William Tombaugh (4-FEB-1906 – 17-JAN-1997), what her husband might have thought about the first mission to the planet he found in 1930. “He’d be very happy about it,” she said, “because he’d really want to know what they were finding out about Pluto.”
Today, Monday January 16, 2012, the New Horizons Team fulfilling that wish mourns Patsy Tombaugh, who died Jan. 12 at age 99. "When we explore Pluto in three years, she will be as much on our minds and our hearts, as she is today," says New Horizons Principal Investigator Alan Stern.
Heliosphere animation
http://upload.wikimedia.org/wikipedia/commons/d/d4/Sentinels_of_the_Heliosphere.ogv 69 259 kB
2 ten-billion-solar-mass black holes at the centers of giant elliptical galaxies
For more than three decades, the central black hole in the supergiant elliptical galaxy M87 — at 6.3 billion solar masses —has been regarded as the most massive known black hole in the Universe. This paper reports two galaxies containing black holes that exceed that figure.
Have you seen the bright "star" near the full moon?
Of course - it is Jupiter: So bright could also Venus be, but Venus could not "move" with the moon that far from the sun: as by "full moon" definition, the full moon is opposite to the sun.
The Moon and Jupiter are separating now, but they'll be together again within the Moon’s sidereal period (27.321661 days): the sun moves eastward about 1°/day (360°/365.2564 days) = about 27° (26.928474° more exactly) eastward. This is why the moon needs slightly more than two days to catch up with the sun to reach the same phase. Thus one cycle of lunar phases takes 29.53 days (Moon’s synodic[phase] period).. This takes a little less than a month — on Nov. 8th and 9th. Until then, browse the links in Space Weather for what you might have missed.
Huge solar flare slams into Earth
The impact of a coronal mass ejection resulted in strong compression of our planet’s magnetosphere.
By NASA's Goddard Space Flight Center, Greenbelt, Maryland — Published: September 27, 2011
A strong-to-severe geomagnetic storm is subsiding following the impact of a coronal mass ejection (CME) at approximately 8:15 a.m. EDT September 26. The Goddard Space Weather Lab reported a strong compression of Earth's magnetosphere. Simulations indicate that solar wind plasma penetrated close to geosynchronous orbit at 9 a.m. Geosynchronous satellites could therefore be directly exposed to solar wind plasma and magnetic fields. Clear locations as far south as the northern United States were witness to aurorae due to the storm. Skywatchers at the highest latitudes should remain alert for northern lights as Earth's magnetic field continues to reverberate from the CME impact.
What causes auroras?
Sunspot 1302 - see also http://spaceweather.com/
Auroras are actually the result of collisions between gaseous particles in the (Earth's) atmosphere with charged particles released from the Sun's atmosphere. Variations in color are due to the type of gas particles that are colliding.
The most common auroral color, a pale yellowish-green, is produced by oxygen molecules located about 100 km above the Earth. Rare, all-red auroras are produced by high-altitude oxygen, at heights of up to 320 km. Nitrogen produces blue or purplish-red aurora.
Recent auroras - in Norway yesterday, Jan 24-25, 2012: http://apod.nasa.gov/apod/astropix.html , http://spaceweather.com/aurora/gallery_01sep11_page4.htm?PHPSESSID=uo3b9q119mn48890359f5aho53
A comet is diving into the sun today. Just discovered by comet hunters Michal Kusiak of Poland and Sergei Schmalz of Germany, the icy visitor from the outer solar system is expected to brighten to first magnitude before it disintegrates on Sept. 14th. The Solar and Heliospheric Observatory is monitoring the comet's death plunge: finder chart, movie, latest images.
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| Full image and caption See animation and full caption |
Full image and caption View image gallery |
| Image credit: Paul Wiegert, University of Western Ontario, Canada |
Image credit: NASA/JPL-Caltech/UCLA |
Asteroid 2010 TK7 is circled in green, in this single frame taken by NASA's Wide-field Infrared Survey Explorer, or WISE.
PASADENA, Calif. – Astronomers studying observations taken by NASA's Wide-field Infrared Survey Explorer (WISE) mission have discovered the first known "Trojan" asteroid orbiting the Sun along with Earth.
Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet. Because they constantly lead or follow in the same orbit as the planet, they never can collide with it. In our solar system, Trojans also share orbits with Neptune, Mars and Jupiter. Two of Saturn's moons share orbits with Trojans.
Scientists had predicted Earth should have Trojans, but they have been difficult to find because they are relatively small and appear near the sun from Earth's point of view.
"These asteroids dwell mostly in the daylight, making them very hard to see," said Martin Connors of Athabasca University in Canada, lead author of a new paper on the discovery in the July 28 issue of the journal Nature. "But we finally found one, because the object has an unusual orbit that takes it farther away from the Sun than what is typical for Trojans. WISE was a game-changer, giving us a point of view difficult to have at Earth's surface."
The WISE telescope scanned the entire sky in infrared light from January 2010 to February 2011. Connors and his team began their search for an Earth Trojan using data from NEOWISE, an addition to the WISE mission that focused in part on near-Earth objects, or NEOs, such as asteroids and comets. NEOs are bodies that pass within 28 million miles (45 million kilometers) of Earth's path around the Sun. The NEOWISE project observed more than 155,000 asteroids in the main belt between Mars and Jupiter, and more than 500 NEOs, discovering 132 that were previously unknown.
The team's hunt resulted in two Trojan candidates. One called 2010 TK7 was confirmed as an Earth Trojan after follow-up observations with the Canada-France-Hawaii Telescope on Mauna Kea in Hawaii.
The asteroid is roughly 300 meters in diameter. It has an unusual orbit that traces a complex motion near a stable point in the plane of Earth's orbit, although the asteroid also moves above and below the plane. The object is about 80 million kilometers from Earth. The asteroid's orbit is well-defined and for at least the next 100 years, it will not come closer to Earth than 24 million kilometers. An animation showing the orbit is available at: http://www.nasa.gov/multimedia/videogallery/index.html?media_id=103550791 .
"It's as though Earth is playing follow the leader," said Amy Mainzer, the principal investigator of NEOWISE at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Earth always is chasing this asteroid around."
A handful of other asteroids also have orbits similar to Earth. Such objects could make excellent candidates for future robotic or human exploration. Asteroid 2010 TK7 is not a good target because it travels too far above and below the plane of Earth's orbit, which would require large amounts of fuel to reach it.
"This observation illustrates why NASA's NEO Observation program funded the mission enhancement to process data collected by WISE," said Lindley Johnson, NEOWISE program executive at NASA Headquarters in Washington. "We believed there was great potential to find objects in near-Earth space that had not been seen before."
NEOWISE data on orbits from the hundreds of thousands of asteroids and comets it observed are available through the NASA-funded International Astronomical Union's Minor Planet Center at the Smithsonian Astrophysical Observatory in Cambridge, Mass.
JPL manages and operates WISE for NASA's Science Mission Directorate in Washington. The principal investigator, Edward Wright, is a professor at the University of California, Los Angeles. The mission was selected under NASA's Explorers Program, which is managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah.
The spacecraft was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
For more WISE information visit: http://www.nasa.gov/wise .
James Webb Space Telescope by NASA - a Hubble Successor
http://www.jwst.nasa.gov/about.html
WEBB, the James Webb Space Telescope (sometimes called JWST) will be a large infrared telescope with a 6.5-meter primary mirror.
Webb was formerly known as the "Next Generation Space Telescope" (NGST); it was renamed in Sept. 2002 after a former NASA administrator, James Webb.
Launch is planned for 2018. JWST will reside in an orbit about at L2 (Lagrangian point 2), 1.5 million km from the Earth: http://www.jwst.nasa.gov/orbit.html Its mirror's 6.5 m total diameter consists of 18 hexagonal segments, each 1.3 m in diameter, and having a mass of approximately 20 kg. These extremely lightweight mirrors are made of beryllium, the lightest hard metal we know.
Backward Sunspot
A strange little sunspot noticed on 31-Jul-06 may herald the coming of an unusually stormy solar cycle. '... a tiny sunspot was born. It popped up from the Sun's interior, floated around a bit, and vanished again in a few hours. On the Sun this sort of thing happens all the time and, ordinarily, it wouldn't be worth mentioning. But this sunspot was special: It was backward.
"We've been waiting for this," says David Hathaway, a solar physicist at the Marshall Space Flight in Huntsville, Alabama. "A backward sunspot is a sign that the next solar cycle is beginning." "Backward" means magnetically backward. Hathaway explains:
Sunspots are planet-sized magnets created by the Sun's inner magnetic dynamo. Like all magnets, sunspots have north (N) and south (S) magnetic poles. The sunspot of July 31st popped up at solar longitude 65o W, latitude 13o S. Sunspots in that area are normally oriented N-S. The newcomer, however, was S-N, opposite the norm.
A picture is worth a 1000 words. In the magnetic map of the Sun, below, N is white and S is black. The backward sunspot is circled:
Above: A SOHO magnetogram of the Sun. July 31, 2006.
This tiny spot of backwardness matters because of what it might foretell: A really big solar cycle.
Solar activity rises and falls in 11-year cycles, swinging back and forth between times of quiet and storminess. Right now the sun is quiet. "We're near the end of Solar Cycle 23, which peaked way back in 2001," explains Hathaway. The next cycle, Solar Cycle 24, should begin "any time now," returning the Sun to a stormy state.
Satellite operators and NASA mission planners are bracing for this next solar cycle because it is expected to be exceptionally stormy, perhaps the stormiest in decades. Sunspots and solar flares will return in abundance, producing bright auroras on Earth and dangerous proton storms in space: full story.
But when will Solar Cycle 24 begin?
"Maybe it already did - on July 31st (2006)," says Hathaway. The first spot of a new solar cycle is always backwards. Solar physicists have long known that sunspot magnetic fields reverse polarity from cycle to cycle. N-S becomes S-N and vice versa. "The backward sunspot may be the first sunspot of Cycle 24." The latest data with NOAA prediction is here:
It sounds exciting, but Hathaway is cautious on several fronts:
First, the sunspot lasted only three hours. Typically, sunspots last days, weeks or even months. Three hours is fleeting in the extreme. "It came and went so fast, it was not given an official sunspot number," says Hathaway. The astronomers who number sunspots didn't think it worthy!
Solar Cycle 24 started as late as 2008
"On January 4, 2008, a reversed-polarity sunspot appeared—and this signals the start of Solar Cycle 24," says David Hathaway of the Marshall Space Flight Center (click).
ASTR-100 texbook pages: 129 - 135. Also, read the latest interesting NASA report here: http://science.nasa.gov/headlines/y2006/15aug_backwards.htm?list917917
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Interesting Books Antonin RUKL: A Guide to the Stars, Constellations, and the Planets; Caxton Editions, London 2000; ISBN 1-84067-050-9; 450 illustrations (incl. 370 in color); 232 pages; obtainable from Heffers, Cambridge, England, at £7.99 http://heffers.co.uk/ Antonín RUKL: Constellation Guidebook; Sterling Publishing Company, New York, N.Y., paper, 224 pages, 2000; $14.95; ISBN 0-8069-3979-6; obtainable from Heffers, Cambridge, England, at £11.99 (about 50 DM, German currency) http://heffers.co.uk/ Antonín RUKL: Atlas of the Moon; Aventinum, Praha, Czech Republic, 1992; ISBN ; out of print (ask Heffers for secondhand copies) http://heffers.co.uk/ Oldrich HLAD, Frantisek HOVORKA, Petr SOJKA & Jitka WEISELOVA: Sky Map 2000.0 (a Wall Map); Publishing House ZES Brno & Astronomical Observatory and Planetarium, Prague, Czech Republic, 1st edition 1998; ISBN 80-902517-0-6, http://www.planetarium.cz Antonin RUKL: The Moon (a Wall Map); Publishing House ZES Brno & Astronomical Observatory and Planetarium, Prague, Czech Republic, 1st edition 1999, 30 years after Apollo 11; ISBN 80-86017-21-4 http://www.planetarium.cz Oldrich HLAD, Frantisek HOVORKA, Petr SOJKA & Jitka WEISELOVA: ATLAS COELI NOVUS 2000.0; Sky Atlas on 40 large 2-sided sheets (24.6" by 17.7" = 62.5cm by 45cm), & Catalogue of 85,000 objects on CD; ETC Publishing Prague & Astronomical Observatory and Planetarium, Prague, Czech Republic, 1st edition 1998; ISBN 80-86006-51-4 (ETC Publishing), ISBN 80-86017-09-5 (OaP Praha). http://www.planetarium.cz Patrick MOORE: Yearbook of Astronomy 2011; MacMillan Publishers 2010, 368 pages; paper ISBN 978-0230752092; http://www.amazon.de |
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Interesting Organizations Sky & Telescope, http://www.skyandtelescope.com/
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