What's Up? - A new brightening source of pollution

Welcome back to What's Up?

During the last Athena Community Astronomy Club meeting one of our club members gave a presentation on light pollution. It's a very important issue and it must be brought to attention.

Light pollution is the brightening of the sky caused by excessive light being emitted from streetlights and other (mostly) man-made lighting. This has been a growing problem ever since the beginning of the industrial era.


Just by looking at a picture of the Earth taken at night (above image - NASA) it's easy to tell that a lot of light is shining upwards. Anyone who lives in or near a large city is very unaware of the many stars that are hidden by the bright city lights. Many people have never seen more than a handful of stars in their lifetimes and have never seen the beauty of the Milky Way.

Astronomers aren't the only ones that have a problem with light pollution. All this extra light can affect people's sleeping cycles and cause a loss of sleep. Medical research suggests that excessive light can cause an assortment of adverse health effects such as increased headache incidence, worker fatigue, increased levels of stress, increase anxiety, and possibly other unknown effects.

Animals are also affected by light pollution. It can confuse animal navigation, change relations between predator and prey, alter competitive interactions, and change animal physiology. Migrating birds can be confused by lights on tall building and other structures. The U.S. Fish and Wildlife Service have estimated that four to five million birds die per year because they are attracted to the lights. This can simply be prevented by turning out lights during migration periods.

When sea turtles hatch from eggs in nests on beaches they head away from the dark outline of dunes and vegetation. When there is artificial lighting they don't know which direction to move in and either die on the beach or get eaten by other animals. Baby seabirds can also be confused by lights as they move out of their nests and fly out to sea.

Lighting used to deter criminals from entering buildings are often enabling criminals. Inadequately placed lighting can remove shadows that would be cast by the criminal and create glare that can hide criminals from sight. Glare from streetlights can also be a hazard to motorists, bicyclists, and pedestrians.

All of this light that is pointed in any direction other than down is wasted. Over-illumination, the excessive use of light, is another cause of light pollution. The U.S. Department of Energy claims that about two million barrels of oil worth of energy are wasted every day (based on the U.S. consuming 50 million barrels of oil per day) because of over-illumination.

Prevention of light pollution can be very simple. Instead of installing incandescent or mercury-vapor bulbs that are currently very popular, low pressure sodium lights can be installed. Low pressure sodium lights are up to ten times more efficient than incandescent light bulbs and low pressure sodium lights are only directed downwards and are shielded so that no light escapes upwards. It also emits only one colour of light which is easy to remove from astronomer's images using computer software. By using less electricity there will be less pollution and money can be saved.


Better shielding (above right versus above left that has very little shielding) for other types of lights can be installed at anytime and can greatly reduce light pollution.

To learn more about light pollution on the web, go to www.darksky.org. Also check out Earth Hour at www.earthhour.org and learn more about this yearly event that raises awareness of light pollution and global warming.

While we can still see through the light pollution, lets take a look at what's up this month.

The moon will be full on Dec. 14 which will shrink to a new moon by Dec. 27.

Venus and Jupiter will be nearby each other low in the western horizon at the start of the month. Venus is the brilliant yellow star-like object. Jupiter is also brilliant but not quite as bright. They will be the two brightest objects in the night sky other than the moon. Moving further into the month, Venus will climb higher into the sky while Jupiter creeps lower and lower towards the horizon. They will be best viewed shortly after sunset.

Mercury will make a brief appearance near the end of the month. It will appear slightly below Jupiter in the western sky. Mercury will be best on Dec. 29 but can be viewed for a few days on either side of that date.

Mars will be heading near the sun and it will be hidden during the month.

At the same time Saturn will be rising in the night sky at about 1 a.m. Saturn will be a dull yellow colour and won't be anything special to look at with the naked eye. If you have the opportunity to use a telescope it will be an entirely different story. The rings will be close to being edge-on to our line of sight. They will appear like a thin golden band around this gaseous planet. By early September 2009 the rings will be perfectly edge-on for the first time in 14 years and disappear from sight since they are so thin.

Until next month, just look up!


Hey Kids...

Last month a large space rock flew into the Earth's atmosphere and exploded! This was a very special event because most space rocks are just pebble sized. They burn up in the atmosphere and create a little trail as they burn up – you may know these as shooting stars. This big space rock is guessed to have weighed 10 tons! It may sound huge but most of it burned up on the way down. A few small pieces have been found in Saskatchewan near a little pond. This may have been the brightest shooting star in Canada in the last 10 years and was completely unexpected. Keep looking up, you never know what you may see!

MacBook videos: Unboxing, First Boot, OS X Welcome Video

Unboxing:


First Boot:


Boot-up Video HD:

What's Up? Space isn't so empty after all

Welcome back to What's Up?

Last month, the Hubble Space Telescope was scheduled to be serviced for the fourth time in its eighteen-year history.

Just a few weeks before this mission was due to leave, one of Hubble's main computers failed. That computer controls the majority of communications with Earth. On October 16, engineers working with the telescope successfully rebooted the backup system. They were about to resume normal scientific operations when problems with the backup system caused it to suddenly go into "safe mode".

The mission to repair Hubble has been delayed until February 2009 or maybe longer, depending on whether the backup system can be up-and-running. If not, they may replace it with a spare that has been in storage for over 20 years.

Everyone will have to hold their breath and see how this turns out.

Since no science is currently being done with the Hubble, let's look at the vacuum of empty space. Is it really empty?

At first glance it may seem like that's the case, but it actually isn't. Let us take a closer look.

Flying in every direction through the universe are photons (particles of light) emitted from stars, quasars, and supernovae, just to name a few. Some photons have been flying through space since nearly the beginning of time. These early photons form what is called the Cosmic Microwave Background (CMB).

The CMB was created about 380,000 years after the universe was created in the Big Bang. The reason all these photons were released at that time is because that's when the universe became transparent to light. Before that time, the universe was so dense that as soon as a photon was given off it hit another particle and was absorbed. The moment the universe became transparent to light was when all this light was released and it now flies through space at the speed of light in all directions.

The CMB has been mapped just to see what the brightness differences in different parts of the sky is like. It was found that it is nearly completely smooth. This shows that the universe was nearly perfectly smooth when it formed. Thankfully there were some small, very slightly denser regions. These regions ended up forming galaxies which allowed us to form over 13 billion years later.

Also shooting through "empty" space are weird little particles called neutrinos. Neutrinos are nearly weightless and rarely interact with other matter. They are mainly formed in nuclear reactions within stars. In fact, you have billions of neutrinos pass through your body every second.

Neutrinos are detected using special neutrino detectors. Neutrino detectors are essentially giant containers of a dense liquid filled with very sensitive light detectors. Every time a neutrino hits one of the liquid particles in the container a flash is given off, and this is detected by one of the light detectors. These neutrino detectors are buried deep below the ground to prevent them from interference with cosmic rays (particles that fly through space and sometimes make it through the atmosphere and would cause a false detection). There is one of these detectors in Canada. It is buried 6800 feet below ground and is located near Sudbury, Ontario.

Imagine an empty box that is impervious to photons and neutrinos. Would it be empty? No. Gravitons are still everywhere.

Gravitons are particles that carry the force of gravity. At this point they're still hypothetical, since they have never been detected. It is impossible to find an area of space where there are no gravitons when we are contained within a universe full of matter (all matter emits gravitons).

Let's imagine that box again except in a universe where there is no matter or anything else mentioned so far. It appears to be finally empty. But it's not yet empty! How can this be?

In the vacuum of space, there is something called vacuum energy. Within every cubic inch of space are millions of particles popping in and out of existence. It is composed of pairs of particles that form because of quantum fluctuations in space. These pairs of particles usually consist of one particle and one antiparticle (made of antimatter - essentially particles that have charges exactly opposite to that in normal matter).

Antimatter and normal matter annihilate themselves when they get near each other. In other words, the two particles vanish, in a flash of energy. This energy is so small that it is nearly undetectable. This was proven in the lab back in 1948 by Dutch physicists Hendrik B. G. Casimir and Dirk Polder. The two scientists placed two small metal plates next to each other and there was a small force of attraction between the two plates. This was caused by vacuum energy.

If all of this doesn't make much sense, don't worry, very few scientists actually understand how this works. Just remember: particles are popping in and out of existence everywhere.

Let's take a look at what is happening with some of the objects among all this "empty space".

On Nov. 13 there will be a full moon and on Nov. 27 will be a new moon.

Space Shuttle Endeavor is scheduled for launch on Nov. 14. It will carry various equipment to the International Space Station.

Until next month, just look up!

Hey Kids...

Did you know that other planets have different amounts of gravity than the Earth? If you were able to stand on Jupiter's surface you would weigh over two times what you weigh on Earth. If you stood on the surface of the moon, you would weigh six times less than what you weigh on Earth. The denser (density is the amount of mass in a certain amount of space) the planet you're standing on, the heavier you will feel. This is because denser objects have a stronger gravitational pull. Go to www.exploratorium.edu/ronh/weight/ to see what you would weigh on other worlds. Just enter your weight in the box provided and click the "calculate" button. Then scroll down and it will say what you weigh on other planets and even what you would weigh on a few stars!

My New MacBook!

On October 14, 2008, the new line of MacBooks were released. With new manufacturing methods, upgraded components (check the specs at the bottom of this article), and the slimmest frame yet, the new MacBooks are true beauty (except they don't have FireWire ports).

It has a beautiful glossy 13.3 inch LCD widescreen display. With support for millions of colors, a LCD back-light (uses 30% less power than the old back-light), and a native resolution of 1280 by 800 pixels make for a stunning display. The black glass around the screen also adds great contrast and beauty (I may over-use that word, after all, it is beautiful, isn't it?).

Enough about that screen. Look at that case!!! Carved out of a single block of aluminum using lasers. Not a single crack or seam to be seen. Actually, there is one - on the bottom hatch that you can slide off to access the hard drive, batteries, and another components. All this is opened up with one simple tab on the bottom.

Here's some pics and a quick description of the features of each one:

Here's a view from an angle to show off the glossy display and thinness of the casing.

Here's a picture of the top portion of the MacBook. In the center you can see the built-in iSight camera and the indicator light to the immediate right of it. The microphone is hidden near the upper left corner above the keyboard.

Apple advertises up to "5 hours wireless productivity". This means, once you fully charge the batteries, you should be able to unplug the laptop and use it nonstop for up to 5 hours. I've tested this out and it seems to be fairly accurate.

The new MacBooks come with the Intel Core 2 Duo processor. My MacBook came with a 2.0 Ghz version of one of these puppies.

Yay! It comes with Blue-tooth! And look, I honestly don't care! I'm never gonna use it. At least it will hep drain my batteries - more money for the electric company when I recharge! I'll just turn it off so it won't be draining my batteries.

Side view of the MacBook showing off the SuperDrive. The drive creates a bit of noise when in use, but that is the nature of a spinning drive. Otherwise, the MacBook is rediculously quiet. In order to hear the fan you have to place your ears right against the keyboard. Sometimes if overheating starts to occur the fans will go full blast for a few seconds or so to clear out the overheated air within the laptop. The hard drive occasionally makes sounds, like when the laptop is opened it makes a small sound for a second or two, but during normal use I rarely ever hear anything from it. This is truly a quiet laptop.

Here's the dimensions of the new MacBook. In the middle is the spot where you open the magnetic latch. To the right is the infrared receiver for the Apple remote (optional, I didn't bother to purchase it). To the left of the notch is small hidden light that can only be seen when the computer goes into sleep mode - the light slowly brightens and dims, as if the laptop is breathing slowly during a good nap.


With the new NVidia GeForce 9400M integrated graphics processors, the new MacBooks achieve up to 6.2 times faster graphics performance (when tested with Call of Duty 4) compared with the Intel processors that were in the old MacBooks.


A quick side view of the ports. There is the MagSafe power port for recharging the MacBook, a Gigabit Ethernet port for wired high-speed internet, two USB 2.0 ports, a Mini DisplayPort for connecting to an external display, a audio-in port (for microphones), an audio-out port (for external speakers or headphones), and a Kensington lock port for connecting to a Kensington lock to secure your laptop to something to prevent it from being stolen. To the right of all these ports is the battering indicator lights. Press the button and the lights will light up indicating how much battery charge is left for use.

The new trackpad is larger than in the old MacBook. This was achieved by building the button into the trackpad. Multi-Touch has been introduced into this trackpad for a greatly enhanced user experience. Scroll through pages by placing to fingers on the trackpad and moving them up and down, resize images by "pinching" with two fingers on the trackpad, use three finger swipes to slide to the next photo in an album (or to flip through items in coverflow), and even more. Definitely one of my favorite features on the new MacBooks.

Finally, the built in Wi-Fi allows me to work anywheres within my house or anywheres outside, as long as I'm fairly close to the wireless router.

Here's the specs of my new MacBook:

WebID:	10111215
Mfr. Part Number:	MB466LL/A
Processor Type	Intel Core 2 Duo
Screen Size	13.3"
RAM (Preloaded / Maximum)	2GB DDR3
Hard Drive	160GB (5400RPM)
Optical Drives	8X SuperDrive (DVD±R DL/DVD±RW/CD-RW)
Graphics	NVIDIA GeForce 9400M
Average Battery Life	5 Hours
Product Weight	2.04 kg
Audio Type	Stereo
Battery Type	Lithium-Ion
Cache	3MB On-Chip Shared L2
Fax/Modem	No
I/O Ports	USB 2.0, VGA Output, Composite Output
Included In Box	AC Adapter, Manual
Network Card	Built-In 10/100/1000BASE-T Gigabit
Other Software	iLife '08, QuickTime, Time Machine
PC Card Slots	No
Pointing Device	Solid-State scrolling Trackpad
Preloaded Operating System	Mac OS X v10.5 Leopard
Processor Speed	2.0GHz
Product Dimensions	32.5(W) x 2.41(H) x 22.7(D) cm
Removable Storage	No
Screen Type	Widescreen LCD
Speakers	Yes
System Bus	1066MHz
Warranty	1 Year Limited Parts & Labour

reevesAstronomy

What's Up? Hubble opened a door to the stars

Welcome back to What's Up?

The final servicing mission to the Hubble Space Telescope is planned for Oct. 14. This mission will repair and/or replace Hubble's instruments and components to allow it to operate into the year 2014.

Let's take a look at what the Hubble Space Telescope (HST) is, what it does, and why it is so important to astronomy.

The HST was first approved by NASA (National Aeronautics and Space Administration) back in 1969 and was referred to as the Large Space Telescope project. Due to budget restrictions, the original proposal was downsized a bit, decreasing the size of the main mirror and a few of the instruments aboard the telescope.

In 1975 the European Space Agency (ESA) joined the project and was to supply solar panels and various instruments with the promise that European astronomers would get a certain percentage of time on the telescope. In 1977 US Congress approved funding for this telescope.

In 1981 it was named after Edwin P. Hubble, an American astronomer (1889-1953). He's the person who confirmed the fact that the Universe is expanding and provided the foundation for the theory of the "Big Bang".
The Hubble Space Telescope was finally launched into space on April 24, 1990, aboard the space shuttle Discovery.

Why would anyone in their right mind want to put a telescope in space? The answer is simple: turbulence.
The Earth's atmosphere is always moving around and bending light. This causes objects viewed in a telescope to be blurry. This is what causes stars to twinkle and is similar to looking across the top of a car on a hot day and seeing the objects in the background to be bent around and giving a blurry image.
To fix this problem you need to get above the atmosphere where there is none of this annoying distortion. This is where the HST comes in.

The HST has a main mirror with a diameter of 2.4 meters (94.5 inches). This is considered small compared with today's giant, ground-based telescopes, but it still is at the forefront of research because of its unique observing location. This primary mirror was made to such great precision that if it were scaled up to the diameter of the Earth, the biggest bump would only be six inches tall.
After its deployment in space it was expected to take the greatest images of space ever taken. After the first few images came in and were examined, it was realized that Hubble's mirror was ground to the wrong curvature! This resulted in terribly blurry images. HST was called by some to be one of NASA's biggest financial blunders.
Luckily, this mistake was fixable. In December, 1993, a servicing mission was sent up to correct this error and upgrade a few instruments. After this "eye surgery", Hubble operated almost exactly like it was expected to!
Now operating to its full abilities, Hubble quickly became an essential component of modern astronomy. It began taking images of the very distant Universe, seeing faint objects never seen before and looking at objects that have been observed in the past except in greater detail than ever before. It has mapped out dark matter in 3D by seeing which way dark matter was tugging galaxies, pinned the age of our Universe at about 13.7 billion years old (much better than the previous estimate of between 10 and 20 billion years old), help us understand how galaxies form, that gamma-ray bursts come from distant galaxies when a giant star collapses in a supernova, and much more. That's just starting to scratch the surface of its many discoveries. All in all, more than 6,000 scientific articles have been published using data from the Hubble Space Telescope!
Hubble's successor, the James Webb Space Telescope, is scheduled for launch in 2013. It will have a special mirror made of many segments that will unfurl itself to the correct shape in space. It has an enormous main mirror, about 6.5 meters (21.3 feet) in diameter!

The James Webb Space Telescope will orbit the sun keeping its distance from Earth at about 1.5 million kilometers (1 million miles), so that it doesn't have to work as hard to keep itself locked on an object like the Hubble does. Since the Hubble flies around the Earth at a speed of 8 kilometers per second (5 miles/sec), it needs to be able to lock onto objects accurately. It can lock on to an object without deviating more than 7/1000th of an arc second (about the width of a hair seen at a distance of 1 mile).
To see where Hubble is orbiting above, go to: http://hubblesite.org/the_telescope/where.a.s_hubble_now/.
Once you're done checking that out, let's take a look at what's going on in the skies this month.

On Oct. 14 there will be a full moon, which will dwindle down to a new moon by Oct. 28.
On Oct. 21 will be the peak of the Orionids Meteor Shower. It will produce about 20 meters per hour at their peak but are very irregular and could give a good show on any morning between Oct. 20-24.

Until next month, just look up!

Hey Kids...

You can build your own model of the Hubble Space Telescope. Just go to http://hubblesite.org/the_telescope/hand-held_hubble/pvc.php for details on supplies and details on how to make it. Make sure to ask for help from parents when it comes to using the drill or the saw. It can be done in 1-3 hours for under $20. Have fun!

First planet imaged around a sun-like star

The enormous 8 meter North Gemini telescope in Hawaii captured what appears to be the first image of a planet orbiting a sun-like star(the planet is circled in the image shown).

According to spectra obtained from the image, the dim object is a planet and not a background star like it may seem at first glance.  The planet weighs in at a whopping 8 Jupiter masses and was 330 AU (Earth's distance from sun: 93 million miles = 1 AU)  from its parent star which was 500 light years away from Earth when this image was taken.

Astronomers are hoping to get a follow-up study on this planet to determine an orbit and learn more about this large world.

Normally, Astronomers take careful measurements of a star's movement as it gets tugged by a nearby planet by seeing if the light is slightly blue or slightly red shifted (called a Doppler shift).  This method works best for very large Jupiter-like planets that orbit really close to their star.  The reason Astronomers haven't been able to image planets like this with ease is not just because they're all too faint, it's because the light from their parent star outshines them and blocks out the light.   It's similar to detecting a spotlight and a firefly a few feet apart on the moon.  Planets are similar to that firefly, they're really hard to see!

Using infrared imaging we can see warm planets like this (it has a temperature of around 1800K or 1500°C) next to a star easily since stars give off less light in the infrared than the visible part of the spectrum.

The star - which was creatively named 1RXS J160929.1-210524 - and its planet are very young, astronomically speaking, at only 5 million years old.  This leaves the planet nice and warm and easy to detect since it gives off a lot of infrared light.

Jupiter sized planets aren't supposed to form so far out from their parent star, according to our current theories, so it's most likely that it formed in closer to its parent star and then slowly migrated outward into the orbit it has today.  Van Kerkwijk (one of the authors of the paper announcing the discovery) thinks that this Jupiter-like planet is uncommon and may only be found in one in every 100 stars.

If you want to read more into this interesting find, click here to read the paper announcing the discovery.  The paper is called "Direct Imaging and Spectroscopy of a Planetary Mass Candidate Companion to a Young Solar Analog" and was written by David Lafrenière, Ray Jayawardhana, and Marten H. Van Kerkwijk.

Dust devils around Phoenix

Recently, with temperatures around the Phoenix Mars Lander changing as Winter on Mars approaches, dust devils have started forming.  Scientists working on the Phoenix mission have noticed that they are steadily increasing in number.  They believe this is caused by the growing difference of day and night temperatures which are currently around -30C and -90C, respectively.  The following animated image is composed of 10 images taken during a Martian night and clearly illustrates the moving clouds that are swirling in the night sky and moves in a westerly direction.  Just click the image below to see the animated image.

Phoenix has photographed several of these dust devils (below image, click for animated image) and has even recorded a drop in air pressure as one passed over the Lander .

One of these dust devils had recorded wind speeds that exceeded 5 meters per second (about 11 miles per hour) and range in size from 2 meters (7 feet) to 5 meters (16 feet).  This was recorded with the telltale during the Martian night and is shown in the below image (those blurs moving in the background are clouds, click for animated image).

The winds from these dust devils are now strong enough to stir up dust and shake the solar panels on the Phoenix lander, moving them up about half a centimeter (0.19 in).  In the below image this effect is shown well as you will see on part of the panel, it was blurred in the image as it moved during an exposure in the image below (the white spikey patch is caused by a few overexposed pixels in the camera, it may be a reflection from the sun).