29
Jan 10

Full Moon Experiment

If your skies are clear tonight, January 29, take advantage of one of the sky watching highlights of the year. A full Moon and Mars will be putting on a show, and the pair will be prominently close to each other in the sky. Plus, this Friday night's full Moon is the biggest and brightest full Moon of the year. It's a "perigee Moon," as much as 14% wider and 30% brighter than other full Moons you'll see later in 2010.

If you have a camera try taking a photo of this full moon and then the next couple of full moons (you’ll need to make sure you keep the camera “settings” the same each time); you should be able to see the difference in the “apparent” diameters .

For more information take a look here: www.universetoday.com/2010/01/28/

Image credit: Universe today - McDonald Observatory

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
29
Jan 10

Full Moon Experiment

If your skies are clear tonight, January 29, take advantage of one of the sky watching highlights of the year. A full Moon and Mars will be putting on a show, and the pair will be prominently close to each other in the sky. Plus, this Friday night's full Moon is the biggest and brightest full Moon of the year. It's a "perigee Moon," as much as 14% wider and 30% brighter than other full Moons you'll see later in 2010.

If you have a camera try taking a photo of this full moon and then the next couple of full moons (you’ll need to make sure you keep the camera “settings” the same each time); you should be able to see the difference in the “apparent” diameters .

For more information take a look here: www.universetoday.com/2010/01/28/

Image credit: Universe today - McDonald Observatory

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
28
Jan 10

The Moon's Seas

A couple of days either side of the full moon is a good opportunity to try and take a look at all the moon’s seas or lunar maria. What you are looking at are, of course, not seas in the conventional sense of the word, they are in fact large, dark, basaltic plains. The plains are less reflective than the mountains or "highlands" as a result of their iron-rich compositions, and hence appear dark (and sea-like) to the naked eye.

With a pair of binoculars you should be able to see eleven Seas and one Ocean; you may also be able to spot a couple of the larger craters such as Tycho or Copernicus. Bon voyage!

Photo credit: Wikipedia

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
28
Jan 10

The Moon's Seas

A couple of days either side of the full moon is a good opportunity to try and take a look at all the moon’s seas or lunar maria. What you are looking at are, of course, not seas in the conventional sense of the word, they are in fact large, dark, basaltic plains. The plains are less reflective than the mountains or "highlands" as a result of their iron-rich compositions, and hence appear dark (and sea-like) to the naked eye.

With a pair of binoculars you should be able to see eleven Seas and one Ocean; you may also be able to spot a couple of the larger craters such as Tycho or Copernicus. Bon voyage!

Photo credit: Wikipedia

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
28
Jan 10

Astronomers Find Rare Beast by New Means

Source: NRAO


Core-collapse supernova explosion
expelling nearly-spherical debris shell.
CREDIT: Bill Saxton, NRAO/AUI/NSF

For the first time, astronomers have found a supernova explosion with properties similiar to a gamma-ray burst, but without seeing any gamma rays from it. The discovery, using the National Science Foundation's Very Large Array (VLA) radio telescope, promises, the scientists say, to point the way toward locating many more examples of these mysterious explosions.

"We think that radio observations will soon be a more powerful tool for finding this kind of supernova in the nearby Universe than gamma-ray satellites," said Alicia Soderberg, of the Harvard-Smithsonian Center for Astrophysics.

The telltale clue came when the radio observations showed material expelled from the supernova explosion, dubbed SN2009bb, at speeds approaching that of light. This characterized the supernova, first seen last March, as the type thought to produce one kind of gamma-ray burst. (read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
27
Jan 10

Solar Eclipse seen from Space

Source: ESA

The annular solar eclipse on 15 January 2010 was observed by the Sun-imaging SWAP (Sun Watcher using APS detectors and imaging processing) instrument on ESA's Proba-2.


The solar Eclipse on January 15th seen by the sattelite Proba-2. Credits: ESA/ROB

This is the same solar eclipse observed on the ground from Africa and Asia, the longest eclipse of the new millennium. It is termed 'annular' because the Moon is further away from the Earth than during a total eclipse, so only part of the Sun is covered. (read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
27
Jan 10

Black Hole Hunters Set New Distance Record

Source:ESO News Release 04/10


Artist's impression about the black hole inside NGC 300 X-1. Credit: ESO/L.Calçada.

Astronomers using ESO’s Very Large Telescope have detected, in another galaxy, a stellar-mass black hole much farther away than any other previously known. With a mass above fifteen times that of the Sun, this is also the second most massive stellar-mass black hole ever found. It is entwined with a star that will soon become a black hole itself. (read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
27
Jan 10

Star Bright

In a previous posting we looked at the fact that not all stars are the same colour, this time we’ll take a look at their brightness. You will have noticed (I hope) that when looking at Orion, not all the stars are of the same brightness. Betelgeuse (top left) and Rigel (bottom right) are much brighter than the stars top right and bottom left which are in turn brighter than the three stars that make up the “belt”!

So, why are some brighter than others? Are they closer? Are they Bigger? Are they hotter? Are they all three? Take some time to think about it (and maybe look at some other stars) and we’ll talk about it in the next posting.

Image credit: Wikipedia - Mouser Williams

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
27
Jan 10

Star Bright

In a previous posting we looked at the fact that not all stars are the same colour, this time we’ll take a look at their brightness. You will have noticed (I hope) that when looking at Orion, not all the stars are of the same brightness. Betelgeuse (top left) and Rigel (bottom right) are much brighter than the stars top right and bottom left which are in turn brighter than the three stars that make up the “belt”!

So, why are some brighter than others? Are they closer? Are they Bigger? Are they hotter? Are they all three? Take some time to think about it (and maybe look at some other stars) and we’ll talk about it in the next posting.

Image credit: Wikipedia - Mouser Williams

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
25
Jan 10

Seeing Double – the “Wow Factor”

If you managed to find the two double stars we talked about in an earlier post, here are a couple of double stars a little more difficult to locate, but with some “wow” factor.

Among the best of all double stars and relatively easy to find is the last star of the string of bright stars that helps make the constellation of Andromeda. The second magnitude star, Gamma (γ)Andromeda (Almach), is stunning through a telescope, even a small instrument showing a superb pair separated by a good 10 seconds of arc.

Another relatively easy to find is Eta Cassiopeia, this double has a nice contrast with stars having yellow and orange colours.


If you would like to learn more about double stars, take a look here: http://en.wikipedia.org/wiki/Double_star/wiki/Double_star

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
25
Jan 10

Seeing Double – the “Wow Factor”

If you managed to find the two double stars we talked about in an earlier post, here are a couple of double stars a little more difficult to locate, but with some “wow” factor.

Among the best of all double stars and relatively easy to find is the last star of the string of bright stars that helps make the constellation of Andromeda. The second magnitude star, Gamma (γ)Andromeda (Almach), is stunning through a telescope, even a small instrument showing a superb pair separated by a good 10 seconds of arc.

Another relatively easy to find is Eta Cassiopeia, this double has a nice contrast with stars having yellow and orange colours.


If you would like to learn more about double stars, take a look here: http://en.wikipedia.org/wiki/Double_star/wiki/Double_star

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
25
Jan 10

WISE discovers its first asteroid

Source: NASA/JPL


The red dot at the center of this image is the first near-Earth asteroid
discovered by NASA's Wide-Field Infrared Survey Explorer, or WISE.
Credit: NASA/JPL-Caltech/UCLA.

NASA's Wide-field Infrared Survey Explorer, or WISE, has spotted its first never-before-seen near-Earth asteroid, the first of hundreds it is expected to find during its mission to map the whole sky in infrared light.

The near-Earth object, designated 2010 AB78, was discovered by WISE Jan. 12. After the mission's sophisticated software picked out the moving object against a background of stationary stars, researchers followed up and confirmed the discovery with the University of Hawaii's 2.2-meter (88-inch) visible-light telescope near the summit of Mauna Kea. (read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
25
Jan 10

Solar Dynamics Observatory ready to launch

Source: NASA/SDO


Artist's impression about the SDO. Credit: NASA/SDO.

The Solar Dynamics Observatory (SDO) is ready to launch! The mission will be launced on February 9th, 2010, from  Goddard Space Flight Center.  SDO will ride a rocket into orbit and begin a new era in Heliophysics, the study of our sun and its effects on Earth and the solar system.

SDO is the first mission to be launched for NASA's Living With a Star (LWS) Program, a program designed to understand the causes of solar variability and its impacts on Earth. SDO is designed to help us understand the Sun's influence on Earth and Near-Earth space by studying the solar atmosphere on small scales of space and time and in many wavelengths simultaneously.

SDO will help us to understand the how and why of the Sun's magnetic changes. It will determine how the magnetic field is generated and structured, and how the stored magnetic energy is released into the heliosphere and geospace. SDO data and analysis will also help us develop the ability to predict the solar variations that influence life on Earth and humanity's technological systems.

SDO will measure the properties of the Sun and solar activity.  (read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
23
Jan 10

Neutralino dark matter stars can not exist

Source: arXiv

Dark matter "clumping" together over time confirming  theories
of how structure formed in our evolving universe.
Credit: NASA, ESA, CalTech

Recent observational data gives an indication that the universe contains a significant fraction (22%) of dark matter whose origin is still unclear. A possible solution to this problem comes from supersymmetric (SUSY) models in the form of neutralino. Neutralino is the lightest supersymmetric partner in SUSY, with the mass of about 100GeV, and is stable. It interacts with the gravitational and weak interactions only, which indicates that it is ”dark”. Weak interactions and neutralino mass are sufficient to satisfy the relic density needed to explain the observed portion of the dark matter in the universe.

Recently a group of astronomers has obtained a detailed distribution of dark matter as a function of the redshift in a part of our universe. Their observations indicate that dark matter plays a role of a scaffolding upon which ordinary matter builds structures. However, the observations show that large pockets with only dark matter (and no ordinary matter) also exist.

De-Chang Dai and Dejan Stojkovic of HEPCOS, Department of Physics, SUNY at Buffalo, have researched the question that arises from the existence of these large pockets of dark matter that is whether compact objects like planets, stars or maybe even large may or not exist.
They concluded that, a stable neutralino star can not exist and also estimated that a stable star can not contain more than a few percents of neutralinos. This information has been published in  the Journal of High Energy Physics (JHEP)(read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
23
Jan 10

The moon – proper motion and apparent motion.

If you have been following the moon this week you should have noticed some interesting things, firstly it has “grown” from a very small crescent to a now “half moon”. Hopefully you will have also noticed that at the same time each night the moon was “higher” and further to the west (to your left when looking towards the moon), you may also have spotted that the moon was not in the same position with regards to the background stars – earlier this week the moon was not too far from a very bright star low on the horizon (the bright star was, and still is, in fact Jupiter) and now it’s a long way from Jupiter and much higher in the sky.

So, what’s been happening? As you know, the moon orbits around the earth (i.e. it has “proper” motion), corresponding to a movement relative to the background stars by an amount roughly equal to its own diameter each hour; this movement is from west to east i.e. the moon starts (as a new moon) low in the western sky and moves slowly “upwards” and eastwards. At the same time, due to the fact that the earth is turning on it’s own axis from west to east, the stars and the moon (and of course the sun) appear to move from east to west. It’s a bit like someone “walking up the down escalator” assuming the person is walking upwards slower than the escalator is going down, he or she will eventually arrive at the bottom of the escalator.

If you would like to know more about the motion of the moon, take a look here: http://en.wikipedia.org/wiki/Orbit_of_the_Moon

If you have a pair of binoculars you can take a look at some of the moons “seas”, you should be able to see (1) Sea of Crisis, (2) Sea of Fertility, (3) Sea of Nectar, (4) Sea of Tranquillity, (5) Sea of Serenity and (6) Sea of Cold.

Photo credit: The Universe Today

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
23
Jan 10

The moon – proper motion and apparent motion.

If you have been following the moon this week you should have noticed some interesting things, firstly it has “grown” from a very small crescent to a now “half moon”. Hopefully you will have also noticed that at the same time each night the moon was “higher” and further to the west (to your left when looking towards the moon), you may also have spotted that the moon was not in the same position with regards to the background stars – earlier this week the moon was not too far from a very bright star low on the horizon (the bright star was, and still is, in fact Jupiter) and now it’s a long way from Jupiter and much higher in the sky.

So, what’s been happening? As you know, the moon orbits around the earth (i.e. it has “proper” motion), corresponding to a movement relative to the background stars by an amount roughly equal to its own diameter each hour; this movement is from west to east i.e. the moon starts (as a new moon) low in the western sky and moves slowly “upwards” and eastwards. At the same time, due to the fact that the earth is turning on it’s own axis from west to east, the stars and the moon (and of course the sun) appear to move from east to west. It’s a bit like someone “walking up the down escalator” assuming the person is walking upwards slower than the escalator is going down, he or she will eventually arrive at the bottom of the escalator.

If you would like to know more about the motion of the moon, take a look here: http://en.wikipedia.org/wiki/Orbit_of_the_Moon

If you have a pair of binoculars you can take a look at some of the moons “seas”, you should be able to see (1) Sea of Crisis, (2) Sea of Fertility, (3) Sea of Nectar, (4) Sea of Tranquillity, (5) Sea of Serenity and (6) Sea of Cold.

Photo credit: The Universe Today

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
22
Jan 10

Seeing Double

Find the constellation of The Plough (also known as the Big Dipper, the Saucepan or the Wagon depending on which country you are in) and take a look at the second star of the “handle” of the saucepan; you should be able to make out a second, fainter, “companion” star. The two stars are sometimes called the "Horse and Rider," in fact the ability to resolve the two stars with the naked eye is often quoted as a test of eyesight.

Many of the stars in the sky are in fact double stars (or even triple or quadruple stars), although not as easy to see as the example above. Many, however, can be seen in a small telescope or even in a pair of binoculars.

What is particularly interesting (and often quite spectacular) is the fact that many of the double stars are often two different colours, yellow and green, or orange and blue for example.

Here are a couple of double stars relatively easy to find.

The Pole star (Polaris) is a very easy double and can be seen in any small instrument
Rigel the bright star bottom right in the constellation of Orion is also easy

In another post we’ll look at some double stars a little more difficult to find, but when you find them or show them to others you will undoubtedly here “wow”!

Photo credit: Wikipedia

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
22
Jan 10

Seeing Double

Find the constellation of The Plough (also known as the Big Dipper, the Saucepan or the Wagon depending on which country you are in) and take a look at the second star of the “handle” of the saucepan; you should be able to make out a second, fainter, “companion” star. The two stars are sometimes called the "Horse and Rider," in fact the ability to resolve the two stars with the naked eye is often quoted as a test of eyesight.

Many of the stars in the sky are in fact double stars (or even triple or quadruple stars), although not as easy to see as the example above. Many, however, can be seen in a small telescope or even in a pair of binoculars.

What is particularly interesting (and often quite spectacular) is the fact that many of the double stars are often two different colours, yellow and green, or orange and blue for example.

Here are a couple of double stars relatively easy to find.

The Pole star (Polaris) is a very easy double and can be seen in any small instrument
Rigel the bright star bottom right in the constellation of Orion is also easy

In another post we’ll look at some double stars a little more difficult to find, but when you find them or show them to others you will undoubtedly here “wow”!

Photo credit: Wikipedia

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
21
Jan 10

A first direct measurement of the intergalactic medium temperature around a quasar at z=6

Source: arXiv


Artist's impression of the heart of a quasar, where a black hole is hidden in a disk of gas and dust.
Credit: NASA Education and Public Outreach at Sonoma State University - Aurore Simonnet.

The thermal state of the intergalactic medium (IGM) provides an indirect probe of both the HI and He II reionisation epochs. Current constraints on the IGM temperature from the Lyα  forest are restricted to the redshift range 2 z 4.5, limiting the ability to probe the thermal memory of HI reionisation toward higher redshift. In this work, the authors using  a high resolution Keck/HIRES spectrum in combination with detailed numerical modelling present the first direct measurement of the IGM temperature around a z = 6 quasar by analysing the Doppler widths of Ly_ absorption lines in the proximity zone of SDSS J0818+1722.(read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon
20
Jan 10

Cat’s Paw Nebula stunning view

Source: ESO - 1003 Photo Release


Portrait of NGC 6334 created from images taken with the
Wide Field Imager instrument at the 2.2-metre MPG/ESO
telescope at the La Silla Observatory in Chile. Credit:ESO.

ESO has just released a stunning new image of the vast cloud known as the Cat’s Paw Nebula or NGC 6334. This complex region of gas and dust, where numerous massive stars are born, lies near the heart of the Milky Way galaxy, and is heavily obscured by intervening dust clouds.(read more)

Twitter del.icio.us Digg Facebook linked-in Yahoo Buzz StumbleUpon