Space and astronomy news
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*Now updated with video!*
We can’t get enough of Comet Lovejoy! But this latest image is off the charts for its beauty and it’s jaw-dropping to contemplate it was taken from space. Dan Burbank, Expedition 30 commander onboard the International Space Station took this image of Comet Lovejoy on Dec. 21, 2011. See more of Burbank’s shots of Lovejoy here.
NASA now has a timelapse video of Burbank’s observations of Comet Lovejoy:
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Officials from Namibia have been examining a hollow ball that fell from the sky back in November 2011. So far, they haven’t had much luck identifying it, so have called in NASA and ESA, hoping the space agencies can provide some answers. The spherical object has a circumference of 1.1 meters (43 inches) and was found in a remote area in the northern part of the country, about 750 kilometers (480 miles) from the capital Windhoek, according to police forensics director Paul Ludik, quoted in an article by AFP.
Ludik described it as made of a “metal alloy known to man” (so cross alien spacecraft part off the list), weighing six kilograms (13 pounds).
This isn’t the first time balls from space have dropped in on unsuspecting countries.
Back in 2008 spherical objects fell to Brazil and Australia, and there have been previous reports of similar objects, as well.
After some post-crash forensics, the two objects in 2008 were identified the as a Composite Overwrapped Pressure Vessel (or COPV), which were carried on the space shuttles, and are a high pressure container for inert gases. COPVs have been used for a variety of space missions.
They are built with a carbon fiber or Kevlar overcoat to provide reinforcement against the vast pressure gradient between the inside and outside of the container, and so can survive re-entry through Earth’s atmosphere.
The one in Namibia was found 18 meters from its landing spot – it created a mini-crater 33 centimeters deep and 3.8 meters wide.
Other suggestions of what the object could be is a piece from a space gyroscope, a satellite part, a tank from one of the Apollo missions, or a part of a Russian spacecraft, (which have been known to crash to the ground, as well)
Sources: PhysOrg, NASA, and thanks to Ian O’Neill for his previous and current articles on this subject
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As 2011 is drawing to a close, the festive season is here and many of us are winding down and looking forward to the holidays. But this is a great time to look ahead to 2012 and pencil into our calendar and diaries the top astronomical events we don’t want to miss next year.
2012 is going to be a great year for astronomy observing, with some rare and exciting things taking place and a good outlook with some of the regular annual events.
So what top wonders should we expect to see and what will 2012 bring?
Conjunction of Venus and Jupiter
On March 15th the Planets Venus and Jupiter will be within 3 degrees and very close to each other in the early evening sky. This will be quite a spectacle as both planets are very bright (Venus being the brightest) and the pair will burn brightly together like a pair of alien eyes watching us after the Sun sets.
This conjunction (where planets group close together as seen from Earth) will be a fantastic visual and photographic opportunity, as it’s not often you get the brightest Planets in our Solar System so close together.
Transit of Venus
For many, the transit of Venus is the year’s most anticipated astronomical event and it takes place on June 5th – 6th. The Planet Venus will pass between the Earth and the Sun and you will see Venus (a small black circle) slowly move across, or “transit” the disc of the Sun.
Transits of Venus are very rare and only a few have been witnessed since the dawn of the telescope. Be sure not to miss this very rare event as the next one isn’t visible for over another 100 years from now in 2117 and the next after that is in 2125.
The full transit of Venus in 2012 will be visible in North America, the northwest part of South America, Western Pacific, North East Asia, Japan, Australia and New Zealand. Other parts of the world will see a partial transit such as observers in the UK, who will only be able to see the last part of the transit as the Sun rises.
First contact will be at 22:09 UT and final contact will be at 04:49 UT
Take note! You have to use the right equipment for viewing the Sun, such as eclipse glasses, solar filters, or projection through a telescope. Never ever look directly at the Sun and never look at it through a normal telescope or binoculars – You will be permanently blinded! The transit of Venus will be a very popular event, so contact your local astronomy group and see if they are holding an event to celebrate this rare occasion.
Meteor Showers
2011 was a poor year for meteor showers due to the presence of a largely illuminated Moon on all of the major showers; this prevented all but the brightest meteors being seen.
In contrast 2012 brings a welcome respite from the glare of the Moon as it gives little or no interference with this year’s major showers. The only other issue left to contend with is the weather, but if you have clear skies on the evenings of these celestial fireworks, you are in for a treat.
If you want to find out more and enjoy the meteor showers of 2012, why not join in with a meteorwatch and visit meteorwatch.org
Jupiter and the Moon
European observers are in for a very rare treat as the Moon briefly hides the planet Jupiter on the morning of July 15th. This “lunar occultation” can be seen from southern England and parts of Europe at approximately 1:50am UT (dependant on location) and the planet re-emerges from the dark lunar limb at approximately 3:10am UT.
This is a great chance to watch this rare and bright event, and it will also be a fantastic imaging opportunity.
Annular Eclipse
American observers will have treat on May 20th with an annular eclipse of the Sun. The eclipse will be visible from many western US states and a partial eclipse visible from most of North America.
Because the Moon’s orbit is not a perfect circle and is slightly elliptical, it moves closer and further away from us slightly in its orbit by 13% and on July 15th it is at its furthest point away from the Earth as it passes in front of the Sun.
Normally the Moon covers the entire disc of the Sun and creates a total solar eclipse, but because the Moon is at its furthest point in its orbit on the 15th, we get an annular eclipse, where we can still see a ring of bright light around the Sun, but we don’t get totality.
The eclipse starts roughly at 6:20pm local time for the Western US states and lasts for four and a half minutes.
As mentioned earlier; never, ever look at the Sun without proper protection such as eclipse glasses or filters for equipment! This can damage your eyes and permanently blind you. This is the same for cameras; the sensitive chips inside can be damaged.
The World Not Ending
Finally we get to December 21st, in which astronomy-minded folks will celebrate the solstice. But in case you haven’t heard, some have prophesied the end of the world, saying the Mayan calendar ends. This has been the subject of much discussion, comedy and media coverage, and it has even been made into films.
Will the Antichrist press the red button and will there be the Rapture? Will the Earth reverse its magnetic poles, or will we get wiped out by a solar flare, rogue comet or asteroid?
Nope, probably not. You can read our entire series which explains why this whole 2012 end-of-the-world craze is complete hokum.
All I know is 2012 is going to be a great year for astronomy with some very interesting, rare events taking place, with many more regular events to see, as well.
I’m sure it’s not going to end.
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It’s been one more day since Colin Legg posted his previous amazing photos and videos of Comet Lovejoy. This new version is even better, especially with it reflecting off the water.
Here’s what Colin had to say about it on IceinSpace:
Had another lovely view of the comet last night wandering the shore of the Estuary. It’s quite unique down there. The Perth and Mandurah sky domes light up the northern half of the sky, while the east and south east are pitch black (except for a couple of small towns). The north glow is enough to walk by once dark adapted.
Anyway, while wandering I came across a small embayment with still water and nice reflections of the comet. Used the same settings as last night to get the attached shot.
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Celebrate the winter holiday season in the company of an ‘Alien Snowman’ on the asteroid Vesta, someone we didn’t even have a clue about until six months ago.
Vesta and the Snowman have been transformed into the beautiful banner above – sent to me courtesy of the Dawn mission team to share with the readers of Universe Today.
Now you can be a creative artist and use the striking new images of Vesta to fashion your own greeting cards (see below) and send seasonal tidings of winter holiday cheer not possible before – all thanks to the remarkably insightful discoveries of Dawn’s international science team.
The Dawn spacecraft orbiting the giant asteroid Vesta is one of NASA’s crowning scientific accomplishments of 2011 because it’s cameras and spectrometers have unveiled a mysteriously diverse world that has no match elsewhere in our solar system.
The more we explore the unknown the more we are enlightened as to just how limited our view of the Universe is from within the narrow confines of our miniscule abode.
The Kepler Space Telescopes latest discoveries of Earth-sized worlds are just the latest examples guiding us to a clearer understanding of our place in the Universe.
Here are just a few of the Vestan images you can masterfully decorate – the Snowman, The Mount Everest of Vesta and the cataclysmically bombarded South Pole.
So, let you imaginations run wild with wintery scenes to match the majesty of this matchless world. The Dawn Education and Public Outreach (EPO) team has created several templates which you can access here
Of course you can also use any of the images posted at the Dawn mission website.
And feel free to post your inspired creations here at Universe Today.
Vesta is the second most massive object in the main Asteroid Belt between Mars and Jupiter.
Dawn arrived in orbit at Vesta in July 2011 for the first ever close up studies of the shattered celestial body. Dawn will spend a year investigating Vesta before spiraling out towards Ceres, the largest asteroid.
Read continuing features about Dawn by Ken Kremer starting here:
Dawn swoops to lowest orbit around Vesta – Unveiling Spectacular Alien World
Rainbow of Colors Reveal Asteroid Vesta as More Like a Planet
Vrooming over Vivid Vestan Vistas in Vibrant 3 D – Video
NASA Planetary Science Trio Honored as ‘Best of What’s New’ in 2011- Curiosity/Dawn/MESSENGER
Dawn Discovers Surprise 2nd Giant South Pole Impact Basin at Strikingly Dichotomous Vesta
Amazing New View of the Mt. Everest of Vesta
Dramatic 3 D Imagery Showcases Vesta’s Pockmarked, Mountainous and Groovy Terrain
Rheasilvia – Super Mysterious South Pole Basin at Vesta
Space Spectacular — Rotation Movies of Vesta
3 D Alien Snowman Graces Vesta
NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin
I’ve finally figured out what to do with all the browser tabs that I have open, but never get around to using: Tumblr. Our new Tumblr blog is a slush pile of links, photos and videos that we just don’t have the time or energy to incorporate into the main Universe Today blog. I’ll warn you, it could easily be 20+ items a day just dumped in there, so if Universe Today is already overwhelming, that’ll be like drinking from a firehose.
Just to let you know, I’m still wrapping my brain around Tumblr, so if you have any suggestions on how to use it better, I’m all ears.
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Looking back in time with some of our best telescopes, astronomers have found one of the most distant and oldest galaxies. The big surprise about this blob-shaped galaxy, named GN-108036, is how exceptionally bright it is, even though its light has taken 12.9 billion years to reach us. This means that back in its heyday – which astronomers estimate at about 750 million years after the Big Bang — it was generating an exceptionally large amount of stars in the “cosmic dawn,” the early days of the Universe.
“The high rate of star formation found for GN-108036 implies that it was rapidly building up its mass some 750 million years after the Big Bang, when the Universe was only about five percent of its present age,” said Bahram Mobasher, from the University of California, Riverside. “This was therefore a likely ancestor of massive and evolved galaxies seen today.”
An international team of astronomers, led by Masami Ouchi of the University of Tokyo, Japan, first identified the remote galaxy after scanning a large patch of sky with the Subaru Telescope atop Mauna Kea in Hawaii. Its great distance was then confirmed with the W.M. Keck Observatory, also on Mauna Kea. Then, infrared observations from the Spitzer and Hubble space telescopes were crucial for measuring the galaxy’s star-formation activity.
“We checked our results on three different occasions over two years, and each time confirmed the previous measurement,” said Yoshiaki Ono, also from the of the University of Tokyo.
Astronomers were surprised to see such a large burst of star formation because the galaxy is so small and from such an early cosmic era. Back when galaxies were first forming, in the first few hundreds of millions of years after the Big Bang, they were much smaller than they are today, having yet to bulk up in mass.
The team says the galaxy’s star production rate is equivalent to about 100 suns per year. For reference, our Milky Way galaxy is about five times larger and 100 times more massive than GN-108036, but makes roughly 30 times fewer stars per year.
Astronomers refer to the object’s distance by a number called its “redshift,” which relates to how much its light has stretched to longer, redder wavelengths due to the expansion of the universe. Objects with larger redshifts are farther away and are seen further back in time. GN-108036 has a redshift of 7.2. Only a handful of galaxies have confirmed redshifts greater than 7, and only two of these have been reported to be more distant than GN-108036.
About 380,000 years after the Big Bang, a decrease in the temperature of the Universe caused hydrogen atoms to permeate the cosmos and form a thick fog that was opaque to ultraviolet light, creating what astronomers call the cosmic dark ages.
“It ended when gas clouds of neutral hydrogen collapsed to generate stars, forming the first galaxies, which probably radiated high-energy photons and reionized the Universe,” Mobasher said. “Vigorous galaxies like GN-108036 may well have contributed to the reionization process, which is responsible for the transparency of the Universe today.”
“The discovery is surprising because previous surveys had not found galaxies this bright so early in the history of the universe,” said Mark Dickinson of the National Optical Astronomy Observatory in Tucson, Ariz. “Perhaps those surveys were just too small to find galaxies like GN-108036. It may be a special, rare object that we just happened to catch during an extreme burst of star formation.”
Sources: Science Paper by: Y. Ono et al., Subaru , Spitzer Hubble
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In the fall of 2006, observers at the Catalina Sky Survey in Arizona found an object orbiting the Earth. At first, it looked like a spent rocket stage — it had a spectrum similar to the titanium white paint NASA uses on rocket stages that end up in heliocentric orbits. But closer inspection revealed that the object was a natural body. Called 2006 RH120, it was a tiny asteroid measuring just a few metres across but it still qualified as a natural satellite just like the Moon. By June 2007, it was gone. Less than a year after it arrived, it left Earth’s orbit in search of a new cosmic companion.
Now, astrophysicists at Cornell are suggesting that 2006 RH120 wasn’t an anomaly; a second temporary moon is actually the norm for our planet.
Temporary satellites are a result of the gravitational pull of Earth and the Moon. Both bodies pull on one another and also pull on anything else in nearby space. The most common objects that get pulled in by the Earth-Moon system’s gravity are near Earth objects (NEOs) — comets and asteroids are nudged by the outer planets and end up in orbits that bring them into Earth’s neighbourhood.
The team from Cornell, astrophysicists Mikael Granvik, Jeremie Vaubaillon, Robert Jedicke, has modeled the way our Earth-Moon system captures these NEOs to understand how often we have additional moons and how long they stick around.
They found that the Earth-Moon system captures NEOs quite frequently. “At any given time, there should be at least one natural Earth satellite of 1-meter diameter orbiting the Earth,” the team said. These NEOs orbit the Earth for about ten months, enough time to make about three orbits, before leaving.
Luckily, and very interestingly, this discovery has implication well beyond academic applications.
Knowing that these small satellites come and go but that one is always present around the Earth, astronomers can work on detecting them. With more complete information on these bodies, specifically their position around the Earth at a given time, NASA could send a crew out to investigate. A crew wouldn’t be able to land on something a few metres across, but they could certainly study it up close and gather samples.
Proposals for a manned mission to an asteroid have been floating around NASA for years. Now, astronauts won’t have to go all the way out to an asteroid to learn about the Solar System’s early history. NASA can wait for an asteroid to come to us.
If the Cornell team is right and there is no shortage of second satellites around the Earth, the gains from such missions increases. The possible information about the solar system’s formation that we could obtain would be amazing, and amazingly cost-efficient.
Thanks to the team from the HiRISE camera on board the Mars Reconnaissance Orbiter, we can enjoy these great wintery-looking views of the Red Planet.
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Jupiter, the largest and most massive planet in our solar system, may be its own worst enemy. It turns out that its central core may in fact be self-destructing, gradually liquifying and dissolving over time. This implies it was previously larger than it is now, and may dissolve altogether at some point in the future. Will Jupiter eventually destroy itself completely? No, probably not, but it may lose its heart…
The core is composed of iron, rock and ice and weighs about ten times as much as Earth. That’s still small though, compared to the overall mass of Jupiter itself, which weighs as much as 318 Earths! The core is buried deep within the thick atmosphere of hydrogen and helium. Conditions there are brutal, with a temperature of about 16,000 kelvin – hotter than the surface of the Sun – and a pressure about 40 million times greater than the atmospheric pressure on Earth. The core is surrounded by a fluid of metallic hydrogen which results from the intense pressure deep down in the atmosphere. The bulk of Jupiter though is the atmosphere itself, hence why Jupiter (and Saturn, Uranus and Neptune) are called gas giants.
One of the primary ingredients in the rock of the core is magnesium oxide (MgO). Planetary scientists wanted to see what would happen when it is subjected to the conditions found at the core; they found that it had a high solubility and started to dissolve. So if it is in a state of dissolution, then it was probably larger in the past than it is now and scientists would like to understand the process. According to David Stevenson of the California Institute of Technology, “If we can do that, then we can make a very useful statement about what Jupiter was like at genesis. Did it have a substantial core at that time? If so, was it 10 Earth masses, 15, 5?”
The findings also mean that some exoplanets which are even larger and more massive than Jupiter, and thus likely even hotter at their cores, may no longer have any cores left at all. They would be indeed be gas giants in the most literal sense.
The conditions inside Jupiter’s core can’t be duplicated in labs yet, but the spacecraft Juno should provide much more data when it arrives at and starts orbiting Jupiter in 2016.