I’m using Twitter?

I signed up for Twitter a couple of years ago, but I never got around to actually using it. Some part of my brain thinks it would be a great way to do… something. But I have no idea what that would be. I’ll need you to teach me, and help me understand what you’d like to see from my Twitter feed.

Obviously, you don’t want to hear about the minutia of my life, but I think there’s value in great big collaborative conversations. Part of me finds it very exciting, and part of me thinks it’s a time sucking black hole. What am I missing?

Here’s my Twitter feed.

Global Warming is Accelerating Faster than can be Naturally Repaired

It appears the Earth’s climate has the ability to naturally regulate atmospheric carbon dioxide levels. Historic records extracted from ice cores show quantities of CO2 have varied widely in the last hundreds of thousands of years. This evidence appears to support the global warming critics view that current observations of the human-induced greenhouse effect is actually naturally occurring and the effects of carbon on the climate is over-hyped. However, a new study shows that although carbon dioxide levels may have been larger in the past, the Earth’s natural processes had time to react and counteract global warming. The current trend of industrial emissions has been far more accelerated than any historic natural process, natural climate “feedback loops” cannot catch up to remove CO2 from the atmosphere.

More bad news about the outlook for our climate I’m afraid. It would appear that the carbon dioxide emissions we have been generating since the Industrial Revolution have increased too rapidly for the Earth’s natural defences to catch up. This new finding comes from the analysis of bubbles of air trapped in ancient ice in Antarctica, dated to 610,000 years ago.

Long before man started burning coal and oil products, the Earth would naturally generate its own carbon emissions. The main polluters were volcanic eruptions, sending millions of tonnes of carbon dioxide into the atmosphere. Surely this had an effect on the state of the climate? Apparently so, but the increased levels of carbon dioxide produced by individual eruptions could be dealt with naturally over thousands of years. The climate wants to be in balance, should one quantity increase or decrease, other mechanisms are naturally triggered to bring the system back into equilibrium.

These mechanisms are known as “feedback loops”. Feedback loops are common in nature, should one quantity change, production of other quantities may speed up. In the case of the carbon emission from volcanic activity, levels of the stuff appear to have been controlled by a natural “negative feedback” loop (akin to a carbon thermostat, when carbon dioxide levels were too high, another process was triggered to remove the carbon dioxide from the atmosphere). However, the sustained atmospheric input of industrial burning of carbon dioxide by human activity has dwarfed historic volcanic carbon output, overwhelming any natural negative feedback mechanism.

This new study is published in the journal Nature Geoscience and carried out co-author Richard Zeebe. In an interview at the University of Hawaii, Zeebe comments on the climate’s ability to remove carbon dioxide from the atmosphere: “These feedbacks operate so slowly that they will not help us in terms of climate change […] that we’re going to see in the next several hundred years. Right now we have put the system entirely out of equilibrium.”

Zeebe and his team noticed that the levels of carbon dioxide and atmospheric temperature correlated, rising and falling together. “When the carbon dioxide was low, the temperature was low, and we had an ice age,” he said. His study states that in the last 600,000 years the carbon dioxide levels have fluctuated only by 22 parts per million. Since the 18th century, human activity has injected 100 parts per million. Humans have increased the quantity of carbon dioxide 14,000 times more than any natural process is capable of doing. This increase has negated any chance for the climate to naturally bring carbon dioxide levels back down to pre-industrial levels in the short term. If we were to stop all emissions tomorrow, it would take the planet hundreds of thousands of years to recover naturally.

Sadly, we’re not even close to slowing carbon emissions. Only last week, the US reported that carbon dioxide levels were up 2.4 parts per million during 2007 alone. The future is bleak for the planet balancing back into its prehistoric atmospheric carbon equilibrium…

Source: Reuters

Hubble Surprise: Heavyweight Baby Galaxies

Astronomers looking at galaxies in the universe’s distant past were surprised to find some compact, very young galaxies that have masses similar to a mature, grown-up galaxy. Using the Hubble Space Telescope, astronomers discovered nine small galaxies, each weighing in at 200 billion times the mass of the Sun. The galaxies, each only 5,000 light-years across, are a fraction of the size of today’s adult galaxies but contain approximately the same number of stars. Each galaxy could fit inside the central hub of our Milky Way Galaxy.

Using the Hubble in conjunction with Keck Observatory in Hawaii, astronomers were able to study the galaxies as they existed 11 billion years ago, when the Universe was less than 3 billion years old.

“Seeing the compact sizes of these galaxies is a puzzle”, said Pieter G. van Dokkum of Yale University in New Haven, Connecticut, USA, who led the study. “No massive galaxy at this distance has ever been observed to be so compact. These galaxies would have to change a lot over 11 billion years, growing five times bigger. They could get larger by colliding with other galaxies, but such collisions may not be the complete answer. It is not yet clear how they would build themselves up to become the large galaxies we see today.”

To determine the sizes of the galaxies, the team used the Near Infrared Camera and Multi-Object Spectrometer on Hubble. For the Keck observations, a powerful laser was used to correct for image blurring caused by the Earth’s atmosphere. Only Hubble, Keck and ESO’s Very Large Telescope are really able to measure the sizes of these galaxies as they are very small and far away.

The ultra-dense galaxies might comprise half of all galaxies of that mass 11 billion years ago, van Dokkum said, forming the building blocks of today’s largest galaxies.

How did these small, crowded galaxies form? One way, suggested van Dokkum, involves the interaction of dark matter and hydrogen gas in the nascent Universe. Dark matter is an invisible form of matter that accounts for most of the Universe’s mass. Shortly after the Big Bang, the Universe contained an uneven landscape of dark matter. Hydrogen gas became trapped in pockets of the invisible material and began spinning rapidly in dark matter’s gravitational whirlpool, forming stars at a furious rate.

Based on the galaxies’ mass, which is derived from their color, the astronomers estimated that the stars are spinning around their galactic disks at roughly 400 to 500 kilometers per second. Stars in today’s galaxies, by contrast, are traveling at about half that speed because they are larger and rotate more slowly than the compact galaxies.

The astronomers say that these galaxies are ideal targets for the Wide Field Camera 3, which is scheduled to be installed aboard Hubble during upcoming Servicing Mission 4 in the fall of 2008.

Original News Source: European Hubble Space Telescope Homepage

Europe Launches the Most Accurate Clock in Space

Where you want to go depends on where you are. And if you’ve got a GPS system in your hands, and the most accurate clock ever sent into space overhead, you’ll always know exactly where you are. ESA’s GIOVE-B satellite blasted into space on Sunday, taking the next step for the deployment of a European satellite navigation system.

The GIOVE-B satellite lifted off from the Baikonur Cosmodrome on April 27th at 4:16 am local time (22:13 UTC Saturday), and placed the Galileo In-Orbit Validation Element B (GIOVE-B) satellite into a 23,200 km orbit.

Ground controllers confirmed that the satellite deployed its twin solar panels, and it was generating electricity within about 5 hours of launch.

On board GIOVE-B are two redundant rubidium atomic clocks, but these are just backups. The really accurate timepiece is the Passive Hydrogen Maser, which has a stability of better than 1 nanosecond a day. There’s no risk of losing track of time with this – it’s the most stable clock operating in Earth orbit.

GIOVE-B is still just a technology demonstration. It will be followed in 2010 by the launch of the first 4 operational satellites that make up the Galileo navigation system. The European plan to eventually have a constellation of 30 identical satellites operating in a constellation.

Original Source: ESA News Release

Looking For a Free Ride To Venus?

The folks over at Ars Technica report that the Japanese Space Agency, JAXA, announced they are now accepting proposals for a microprobe that can hitch a ride with the Venus Climate Orbiter, Japan’s upcoming robotic mission to Venus. They will provide a free ride to either a low-Earth orbit or on a trajectory toward Venus. There are just a few requirements that JAXA has specified:

The launch booster for the Venus Climate Orbiter has room for one piggyback probe that can weigh up to 40 kilograms. It must fit into a 50x50x50 centimeter cube. After the microprobe is released, it will be on its own. JAXA will not assist with further correcting its trajectory or inserting it into an orbit around Venus.

The proposal must be submitted by a researcher based at a Japanese institution, and the mission will have to be managed in Japan. However, this does not preclude a Japanese team from collaborating with foreign researchers on a proposal. Also, all the documents for information and proposals are written in Japanese.

But if you’re in the market for a ride to Venus, the deadline for submitting your proposal is May 23, 2008. The announcement of JAXA’s micro-satellite program is posted here, and the specific announcement for piggybacking on Venus Climate Orbiter is here. The requirements for the micro-satellite and the application forms are found here.

Piggybacked micro-mission to a planet has been done before: NASA’s failed Mars Polar Lander mission had two accompanying microprobes, each weighing only 2.4 kilograms, that would have penetrated the Martian soil to take measurements if the mission had gone better. Mars Polar Lander and the two penetrator probes—named Deep Space 2—all failed independently of one another.

Original News Source: Ars Technica

10 Satellites Launched in Record Setting Mission for India (Video)

India’s space agency sent a record 10 satellites into Earth orbit with a single launch early Monday. The Polar Satellite Launch Vehicle (PSLV) rocket ejected all the satellites within minutes of each other after liftoff from the Sriharikota space station in southern India. Initial signals indicated all the satellites were working normally. India is seeking to compete with other space-faring nations for commercial launch services, and this mission’s success demonstrates India’s ability to launch multiple payloads into precise orbit. The flight breaks the previous record of eight satellites launched at once by a Russian rocket, according to Indian news reports.


It was the 13th flight of the Polar Satellite Launch Vehicle, which has “repeatedly proved itself as a reliable and versatile workhorse launch vehicle,” said Indian Space Research Organization (ISRO.) Later this year India will launch its own a lunar mission, Chandrayaan which will orbit the moon to create chemical and topographical maps.

The satellites included a 690-kilogram (1,518-pound) remote-sensing satellite, Cartosat-2A, an 83-kilogram mini-satellite and a cluster of eight so-called nano-satellites, each weighing between three kilograms and 16 kilograms. The two larger satellites were built by the ISRO, but the nano-satellites were built by research institutions from Europe, Canada and Japan.

“[India] wants to market its launch systems and also its capability in earth imagery,” said Ajay Lele, a space expert at the Institute of Defence Studies and Analyses in New Delhi. “The mission is very significant from a commercial point of view.”

“The mission was perfect,” said ISRO chairman G. Madhavan after the launch was telecast live.

“It is a historic moment for us because it is the first time that we have launched 10 satellites in a single mission,” he added.

Cartosat-2A, the main satellite launched Monday to an altitude of 630 kilometres (391 miles) above earth, also has a domestic economic dimension and can be used for intelligence gathering as well, officials say.

Here’s a YouTube Video from an Indian television station (in English) with more information about the launch.

Last year, India launched an Italian spacecraft into orbit, and in January 2008, it launched an Israeli spy satellite.

For more information about India’s space agency: ISRO.

Original News Source: AFP

Globular Clusters Are Less Evolved than Astronomers Thought

Some of the oldest structures in the Milky Way are the globular clusters. Ancient collections of millions of stars, that have held together by mutual gravity over billions of years. But new data collected by NASA’s Chandra X-Ray Observatory casts doubt on their “ancient nature”. They might be surprisingly less mature than astronomers previously believed.

According to conventional wisdom, globular clusters pass through three phases of evolution in the development of their structure: adolescence, middle age, and old age. Keep in mind, we’re talking about the age of the cluster here, not the age of the individual stars in the cluster.

One way to calculate the age of a cluster is to look for the presence of binary X-ray sources. These happen when two stars get so close to one another that they begin to transfer mass. The transfered material piles up into an accretion disk around one star, which can blaze brightly in the X-ray spectrum. Globular clusters should form these X-ray binaries in their middle age, and then lose them again as they reach old age.

Recent images from NASA’s Chandra X-Ray Observatory revealed the number of bright X-ray sources in two globular clusters: NGC 6397 and NGC 6121. While they were expecting to see less double stars in NGC 6397, it was just the opposite.

Instead of most globular clusters being in their middle ages, astronomers are starting to think that many are in an adolescent stage of evolution. When astronomers surveyed 13 globular clusters, 10 were in adolescence and only 3 were middle aged.

With so many clusters in the earlier stags of their evolution, the later stages must take much longer to reach than astronomers previously believed. Even though the clusters are already billions of years old, they’ve barely reached their prime.

Original Source: Chandra News Release

Book Review: The Mystery of the Missing Antimatter

Good mystery novels keep you in suspense to the very end. Luckily, our universe does the same to us. While we learn more, we learn that we have so much more to go. Helen Quinn and Yossi Nir in their book The Mystery of the Missing Antimatter look at one outstanding puzzle of particle physics. Suspense may lack somewhat but there’s no doubting that some high powered intellects are exercising lots of gray matter.

So, why would anyone think that antimatter is missing. Well, most people wouldn’t even acknowledge the existence of antimatter. Nevertheless through a simple process of deductive reasoning, principally via the rules of symmetry, Quinn and Nir let the reader know that matter needs antimatter. We do see lots of matter in our universe whether planets, stars or galaxies. Yet, there are no apparent globs of antimatter. So, either they lie hidden or they must have disappeared. This is the mystery that Quinn and Nir tackle.

With the theme of a murder mystery installed in the reader by a silhouette on the cover, this book takes the reader on a tour de force of the case at hand. That is, since about the last hundred years, we read of researchers who’ve developed models and experiments that have dived ever deeper into what is matter. Atoms gave way to protons, neutrons and electrons. These gave way to mesons, fermions, bosons, hadrons and leptons. Finally we read of the latest on the scene; the neutrinos with mass. How do these relate to matter? Well, via symmetry. That is, whatever we begin with, we will end with. This is the supposition that’s carried throughout the book. So, when small particles in accelerators crash together, the remnants must, in sum, equal the beginning, accounting for charge, mass and spin. This, the reader learns, is the simple basis for advancements in particle physics and its perception of the tiniest of the tiny. And this basis explains why antimatter must be accounted for somewhere or somehow.

Now this book is in a series entitled Science Essentials. Its objective is to convey to the reader, in clear prose, the fundamental knowledge underlying a rapidly evolving field. The book meets this need as it proudly trumpets the lack of any equations or math. Yet, it also lacks charts and explanatory figures. In particular, there’s a lack of an easy reference that links all the particles and variables together. For instance, reading of “each charged lepton converting to a single type of neutrino when it emits or absorbs a W-boson” can quickly lose a reader who is not familiar with particles, charms and colours as they relate to particle physics. Sure, the authors take the reader by the hand for introductions to each, but there’s a lot of which to keep track as one proceeds to “neutral particles of definite mass [that] are admixtures of two states of different strangeness”. Yes, this verbiage is essential and does build on itself. But, unless already indoctrinated, the reader will quickly feel overwhelmed. Essentially, all the words are familiar but they’re used in a very different way than as normally spoken on the street. Reading this book will help the average reader in understanding the relevant press clippings. It certainly won’t dish out all the tricks of the particle physicist

Yet, this lack of affinity is perhaps the failing of the average reader rather than the writer. This book takes the reader on a breathtaking foray into the depths of the particles that make-up our body and our worlds. A flavourful timeline at the end of the book shows just how quickly our knowledge is transporting us into an existence of knowing. As the authors note, our understanding increases but we still don’t know why antimatter is missing. But we know it exists and we’re not giving up the search. It is good to be more aware of our existence and this book does provide the necessary background even though the reader may need to re-read or passage or two.

Assuming the universe came from nothing, then the sum of its parts must still be nothing. Hence matter that we readily see must have an equivalent antimatter. But where? Helen Quinn and Yossi Nir consider this in their book The Mystery of the Missing Antimatter. And, like an affable Dr. Watson, the reader can journey with them as they explore this still unsolved case.

Read more reviews or purchase a copy online from Amazon.com

Podcast: The End of the Universe Part 1: The End of the Solar System

planetary nebula
Planetary nebula. The future for our Sun. Image credit: Hubble

This is a show we wanted to do since we started Astronomy Cast but we always thought it was too early. We wanted you to know that we’re positive, happy people with enthusiasm for astronomy and the future. It’s time for some sadness. It’s time for a grim look to see what the future holds for the Universe. This week we stay close to home and consider the end of humanity, the Earth, the Sun, and the entire Solar System. Next week we’ll extend out to the very end of the Universe.

Click here to download the episode

The End of the Universe Part 1: The End of the Solar System – Show notes and transcript

Or subscribe to: astronomycast.com/podcast.xml with your podcatching software.

The Earth’s Cities at Night

You only have to walk outside at night, look up and not see the Milky Way to know that light pollution is a problem. And seen from space at night, the Earth’s surface glows with the light of millions of homes, buildings, cars and streetlights. Seen at night, our impact on the Earth is immediate and obvious.

A few years ago, NASA and NOAA compiled a complete world map of the nighttime Earth, using 9 months of data collected by satellites. This “Night Lights” image is pretty famous, and widely circulated around the Internet.

There’s a great article at NASA’s Earth Observatory that describes how they capture these night images of the Earth’s surface. You can also see many of the best images taken so far.

Click here to read the article.