ODIN SATELLITE OBSERVES WATER IN COMET 103P/HARTLEY 2

A map of water in Comet Hartley 2, observed by Odin on 29 October
2010. Copyright 2010 Swedish Space Corporation/Centre National
d’Etudes Spatiales/Observatoire de Paris.

The Odin satellite observed Comet Hartley 2 almost continuously from 29 October to 1 November. The water signature (line) was easily detected. Its extension and space distribution is shown on a map (Fig. 1). The production of water derived from the observations ranges from 180 to 300 kg (400 to 660 lb) per second.


This production of water (Fig. 2) is rapidly varying with time. This is in line with variations reported from other means of observation. It may be related to the rotation of the comet's nucleus, for which periods around 17h have been reported.

Comet 103P/Hartley 2 is a Jupiter-family comet orbiting the Sun close to the ecliptic plane, with a period of 6.5 years. Its return this year is exceptional. It passed perihelion on 28 October at 1.059 AU from the Sun (158 million km; 98 million miles) and on 20 October, it came close to the Earth, at only 0.121 AU (18 million km; 11 million miles). Furthermore, it is the target of NASA's mission EPOXI, which is to fly by the comet on 4 November.

At this occasion, this comet is the object of an intense, international campaign of observation which mobilizes all major astronomical resources, including the Herschel Space Observatory. The Odin satellite is participating to this campaign.

The Odin satellite is a small spacecraft, orbiting the Earth, designed and built by Sweden, in collaboration with Canada, Finland and France. It was launched in February 2001. Aimed for studying both the Universe (astronomy) and the terrestrial atmosphere (aeronomy), it allows for the observation of a number of molecular lines, at radio (submillimeter range) wavelengths, otherwise not accessible from the ground: in particular the fundamental water line at 556.9 GHz.

Odin is thus well suited for the study of water, the main constituent of cometary ices, released as water vapor following heating of cometary nuclei by the Sun.

Since its launch, Odin has observed about 15 comets. Now closed for astronomical observations, the Odin satellite concentrates on aeronomical studies, except for special occasions such as the passage of Comet Hartley 2.

Figure 2:

http://www.lesia.obspm.fr/perso/jacques-crovisier/odin_hartley_2.jpg


The evolution of the production of water in Comet Hartley 2, as observed with Odin. Copyright 2010 Swedish Space Corporation/Centre National d'Etudes Spatiales/Observatoire de Paris.

Reference:International Astronomical Union electronic telegram No. 2524.

Solar ring sigbaar in Gauteng: Pretoria en Secunda

Foto:  Roland Friend, Secunda.

So 10:30 (Maandag 1 November) bel my broer Ben uit Johannesburg. "Daar's `n sirkel om die son! Gaan kyk! Ek besef dadelik wat dit is, want die vorige een was `n sirkel om die maan (Sien blog). Tog loer ek by die venster uit en sien niks. Dit het toe die vorige dag by hulle gereën en hoë cirrus wolke was nog in die lug. 

• (Sien blog vir sirkel om die maan).

Skaars `n halfuur later storm  kollega Nellie Friend  van die Universiteit by my in en vertel van die kring om die son, maar die son is te skerp en sy  kan dit nie sien nie. Haar seun, Roland Friend van Secunda het gebel en gesê sy moet kyk. Hy het ook die foto hier bo geneem en vir ons aangestuur. 

Ek kan nie die foto dadelik op die blog laai nie en stuur dit vir Auke Slotegraaf in die Kaap. Hy is toe in dieselfde bootjie - besig om van internet versakaffers te verander. Hy kon toe darem die foto gistermiddag op sy blog gaan laai.

Besoek dit gerus: psychohistorian.org en lees meer oor die verskynsel.

Solar ring visible in Gauteng Pretoria and also Secunda.

Cosmonaut flies resupply ship to space station docking

File photo of approaching Progress spacecraft. Credit: NASA

BY JUSTIN RAY
SPACEFLIGHT NOW
Posted: October 30, 2010

For the 40th time in the past decade, a Russian cargo freighter has arrived at the International Space Station carrying vital supplies to feed the needs of the orbiting laboratory and its resident crews. But this docking required the intervention by one of the most experienced cosmonauts.

The Progress M-08M spacecraft, flying on autopilot, performed a flawless rendezvous with the space station after a three-day journey from the Baikonur Cosmodrome launch pad, but some yet-unspecified problem at the last minute prompted cosmonaut Alexander Kaleri to take over manual control and guide the vehicle to docking.

The successful linkup to the Pirs docking compartment came at 12:36 p.m. EDT (1636 GMT) while soaring 220 miles over western Kazakhstan.

Hooks and latches were engaged a few minutes later to firmly secure the 24-foot-long craft to the station.

The Expedition 25 crew of commander Doug Wheelock, fellow NASA astronauts Shannon Walker and Scott Kelly, and Russian cosmonauts Fyodor Yurchikhin, Oleg Skripochka and Kaleri plan to open hatches and enter the Progress later today.

The cargo includes 2,804 pounds of equipment, food, clothing and life support system gear, 1,918 pounds of propellant to replenish reservoirs that feed the Russian maneuvering thrusters, 498 pounds of water and some 110 pounds of oxygen and air for the station's atmosphere.

The Progress was launched Wednesday atop a Soyuz rocket from Baikonur Cosmodrome, reaching a preliminary orbit of 151 by 120 miles. A series of precise engine firings propelled the freighter on the orbital chase.

After arriving in range of the space station today, the vessel began a flyaround maneuver to get lined up with the docking port and then executed a roll maneuver to properly orient its solar wings with surrounding structures around the Pirs module.

A brief stationkeeping hold with about 650 feet between the freighter and station allowed Russian flight controllers to assess systems before giving approval to commence the final approach.

It was during stationkeeping that Russian flight controllers in Moscow instructed Kaleri to activate the TORU manual docking equipment and take over the piloting tasks from the Progress' autonomous KURS system.

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Encounters with Comet Hartley 2

by Greg Bryant and the editors of Sky & Telescope

The diffuse coma of Comet Hartley 2 was more than 1° wide on October 13th, when Nick Howes took this image with a 4-inch apochromatic refractor in Wiltshire, U.K. Stars are shown by short exposures in the blue and green channels; the comet is shown as a full-color long exposure. Howes has also been remotely operating the 2-meter Faulkes North Telescope in Hawaii. Using this he has measured the rotation rate of the comet's nucleus to be 19 ± 1.5 hours.

Nick Howes

 

More Images

Comet Hartley 2 a "6-inch spinning cucumber!"

Twelve radar images of the nucleus of comet Hartley 2 were obtained by the Arecibo Observatory's planetary radar from Oct 25 to 27, 2010. Image credit: NAIC-Arecibo/Harmon-Nolan 

 Provided by JPL/NASA (news : web)

 Exactly one week before the world gets a new look at comet Hartley 2 via NASA's EPOXI mission, observations of the comet by the Arecibo Planetary Radar in Puerto Rico have offered scientists a tantalizing preview. 

"It kind of looks like a cross between a bowling pin and a pickle," said EPOXI project manager Tim Larson of NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Only it's about 14-thousand-times larger and hurtling through space at 23 miles per second." A new image is online at http://www.naic.ed … ~pradar/103P . 

Scientists using Arecibo's massive radar dish began observations of Hartley 2 on Oct. 24, just four days after the comet made its closest approach to Earth since its discovery in 1986. (On Oct. 20, the comet came within 17.7 million kilometers, or 11 million miles, of Earth). The observations are scheduled to continue through Friday, Oct. 29. 

During the Nov. 4 flyby, the cameras aboard the EPOXI mission spacecraft will get within 700 kilometers (about 435 miles) of the comet.\

"Observing comet Hartley 2 from the Earth with radar was like imaging a 6-inch spinning cucumber from 836 miles away," said Jon Giorgini, a scientist at JPL and a member of the Arecibo team that imaged the comet. "Even without all the data in, we can still make some basic assertions about Hartley 2. Its nucleus is highly elongated and about 2.2 kilometers [1.4 mile] long, and it rotates around itself about once every 18 hours. In addition we now know the size, speed and direction of particles being blown off the comet, and we immediately forwarded all this information to the EPOXI team." 

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Space station on to the 2nd decade (ISS)

NASA astronaut Tracy Caldwell Dyson, Expedition 24 flight engineer, replaces a dewar tray containing biological samples in the Minus Eighty Degree Laboratory Freezer for ISS in the Kibo laboratory of the International Space Station. Image Credit: NASA

Provided by JPL/NASA (news : web)

The second decade of a new era in human history -- when not everyone lives on our home planet -- begins Nov. 2, 2010, as the International Space Station crosses the 1.5 billion mile mark of its travels with six residents on board and six visitors en route. 

 On Oct. 25, the station also set a record for being the longest continuously inhabited spacecraft. On that day, the International Space Station eclipsed the previous record of 3,644 days set by the Russian Mir Space Station. With each new day, NASA and its partners are pushing the envelope of human achievement in space into uncharted territory.

Ten years ago, Bill Shepherd, Yuri Gidzenko and Sergei Krikalev launched into history as the first crew to live on the International Space Station. They blasted off from the Baikonur Cosmodrome in Kazakhstan on Oct. 31, 2000, and docked with the station two days later. From the moment the hatch of their Soyuz spacecraft opened and they entered the fledgling space station, there have been people living and working in orbit, 24 hours a day, seven days a week, 365 days a year.

“As we look forward to the next 10 years, taking us through 2020, the space station will serve many roles,” said Mike Suffredini, International Space Station program manager since 2005. “With its permanent human presence, it will serve as a foothold for long-term exploration into space, being an integral part of testing human endurance, equipment reliability and processes essential for space exploration.”

Before his launch, Expedition 1 commander Shepherd explained that the station “gives us unique access to the space environment where we hope we can do very interesting and productive research, but it really means we [will] develop a lot of the capabilities and technology that’ll allow humans to go elsewhere away from the planet.”

Read more... (A Must read!)

Leaks delay final launch of space shuttle Discovery

The launch of the space shuttle Discovery on its final scheduled mission has been delayed by at least 24 hours until Tuesday because of a leak in a pressurization system, NASA said.

"We have developed two leaks on the pressurization system on the maneuvering system of Discovery on the right side," Kennedy Space Center spokesman Allard Beutel told AFP on Friday.

Fixing the shuttle and getting it ready for take-off would take until "Tuesday at the earliest," the spokesman added.

Discovery and its crew of six astronauts had been scheduled to launch Monday on its last mission to the International Space Station, but that now has been reset for 4:17 pm (2017 GMT) Tuesday, assuming repairs are successful, NASA said.

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Eutelsat suffers spacecraft loss

By Jonathan Amos
Science correspondent, BBC News   

The Paris-based Eutelsat company says its latest spacecraft has failed less than 24 hours after being launched on an Ariane rocket from French Guiana.

The satellite operator said the W3B platform had developed a leak in its propellant system and could not raise itself to its operational orbit.

The 5.3-tonne spacecraft was to have been stationed high above the equator at 16 degrees East, to provide TV, radio, internet and other data services to Europe, Africa, the Middle East and Indian Ocean islands.

The company already has another satellite in production called W3C, and this will be moved into the 16-East slot when it launches in the second half of 2011.

"It's a massive disappointment," said Eutelsat's Vanessa O'Connor, "but our job now as an operator is to continue our services and make sure W3C gets there as soon as possible, and that we expedite the new programme to replace W3B," she told BBC News.

Read more...
 

Time Will End in Five Billion Years, Physicists Predict

Ker Than

for National Geographic News

Published October 28, 2010

Our universe has existed for nearly 14 billion years, and as far as most people are concerned, the universe should continue to exist for billions of years more.

But according to a new paper, there's one theory for the origins of the universe that predicts time itself will end in just five billion years—coincidentally, right around the time our sun is slated to die.

The prediction comes from the theory of eternal inflation, which says our universe is part of the multiverse. This vast structure is made up of an infinite number of universes, each of which can spawn an infinite number of daughter universes. (Related: "New Proof Unknown 'Structures' Tug at Our Universe.")

The problem with a multiverse is that anything that can happen will happen an infinite number of times, and that makes calculating probabilities—such as the odds that Earth-size planets are common—seemingly impossible.

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Superhero suit to strengthen astronauts' bones

Source: NewScientist 

 

WITH its stitching clearly visible and reference lines drawn in marker pen, the stretchy superhero-blue suit at the Massachusetts Institute of Technology's Man Vehicle Laboratory doesn't look like much. But if it works as planned it could offer orbiting astronauts a replacement for something they are sorely missing: gravity.

The microgravity of orbital flight is tough on the bones. Even with regular exercise, an astronaut can lose 1.5 per cent of the mass of some bones in the hips and lower back in just one month. That is similar to the bone loss experienced by a post-menopausal woman in a year.

To combat the problem, Russian cosmonauts on the International Space Station wear space suits designed to mimic gravity. Bungee cords on the suit's arms and legs exert a force that simulates the body's weight. But these suits are difficult to wear for long periods, and it is not clear how effective they are in preventing bone loss.

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