Category: Astronomy

• Windows on the Universe – This site has a Solar System coloring book you can print off. It offers a Java version or a PDF version.
• Enchanted Learning – Here’s another Solar System coloring book. This one contains images of all the planets, the Sun, the Moon, and other astronomical objects that you can color in.
• Johnson Space Center (NASA) – Of course, NASA has some coloring books you can use. Here’s one that covers human spaceflight.
• Solar System Coloring Book – This one comes from the Space Store. It’s not free, but it’s only $3.95 and has each of the planets.
• Exploring the Solar System – Another book you can buy. This one is available from Amazon.com.

Let us know if you find any other books for coloring the Solar System.

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A team of astronomers has found what they say is the clearest detection to date of dark energy in the universe. Scientists at the University of Hawaii compared an existing database of galaxies with a map of the cosmic microwave background radiation (CMB), and were able to detect dark energy’s effect on vast cosmic structures such as superclusters of galaxies, where there is a high concentration of galaxies, and supervoids, areas in space with a small number of galaxies. “We were able to image dark energy in action, as it stretches huge supervoids and superclusters of galaxies,” said Dr. István Szapudi said, from U of Hawaii’s Institute for Astronomy.

The discovery in 1998 that the universe was actually speeding up in its expansion was a surprise to astronomers. Dark energy refers to the fact that something must fill the vast reaches of mostly empty space in the Universe in order to be able to make space accelerate in its expansion. Dark energy works against the tendency of gravity to pull galaxies together and so causes the universe’s expansion to speed up.But the nature of dark energy and why it exists is one of the biggest puzzles of modern science.

The team from the University of Hawaii made the discovery by measuring the subtle imprints that superclusters and supervoids leave in microwaves that pass through them. Superclusters and supervoids are the largest structures in the universe.

“When a microwave enters a supercluster, it gains some gravitational energy, and therefore vibrates slightly faster,” explained Szapudi. “Later, as it leaves the supercluster, it should lose exactly the same amount of energy. But if dark energy causes the universe to stretch out at a faster rate, the supercluster flattens out in the half-billion years it takes the microwave to cross it. Thus, the wave gets to keep some of the energy it gained as it entered the supercluster.”

“Dark energy sort of gives microwaves a memory of where they’ve been recently,” postdoctoral scientist Mark Neyrinck said.

When the team compared galaxies against the CMB, they found that the microwaves were a bit stronger if they had passed through a supercluster, and a bit weaker if they had passed through a supervoid.

“With this method, for the first time we can actually see what supervoids and superclusters do to microwaves passing through them,” said graduate student Benjamin Granett.

The signal is difficult to detect, since ripples in the primordial CMB are larger than the imprints of individual superclusters and supervoids. To extract a signal, the team averaged together patches of the CMB map around the 50 largest supervoids and the 50 largest superclusters that they detected in extremely bright galaxies drawn from the Sloan Digital Sky Survey, a project that mapped the distribution of galaxies over a quarter of the sky.

The astronomers say there is only a one in 200,000 chance that the evidence they detected would occur by chance.

Original News Source: U of Hawaii press release

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“A drop fell on the apple tree, Another on the roof; A half a dozen kissed the eaves, And made the gables laugh. A few went out to help the brook, That went to help the sea. Myself conjectured, Were they pearls, What necklaces could be!” As you drink in the words of Emily Dickinson, get ready for two showers of another type this week: meteor showers.

Beginning this evening, July 27, the Delta Aquarid meteor shower will peak with an average of 25 “shooting stars” per hour for maximum activity with many of them leaving yellowish trails. While there is no specific parent comet for the shower, many believe they are the product of periodic Comet 96P/Machholz 2 – which disintegrated in 1994. Will this cause the activity to be stronger or not? No one really knows for sure. Fall rate activity is always dictated by the precise moment the Earth turns into the meteoroid stream and no specific location or time can ever be precise.

But don’t be discouraged if it’s cloudy tonight. This whole week will be a grand time to watch for meteors as the Capricornid meteor shower peaks on July 29. This time we’re looking at about 15 to 20 meteors per hour, but a shower that also has a reputation for bolides. Who among us doesn’t get a thrill at watching a bright fireball pass overhead!

“Dazzling and clear shooting over our heads, A moment, a moment long it sail’d its balls of unearthly light over our heads, Then departed, dropt in the night, and was gone.”

Numerous astronomers have tried to identify the object responsible for the formation of the Alpha Capricornid stream, but no definitive parent has ever really been chosen because the stream is so broad. It may be Denning-Fujikawa, or it could be Honda-Mrkos-Pajdusakova, but I like to think it might be possible that Apollo asteroid Adonis is the case. Although there is radio evidence to support that, I still find something dreadfully romantic about spending an evening watching for meteors and what more romantic figure than Adonis?

“As I flit through you hastily, soon to fall and be gone, what is this chant, What am I myself but one of your meteors?” Over time, meteor showers have inspired poets and artist alike, just like these words from Walt Whitman. How long has it been since you read a poem, or contemplated the evening sky? With the Moon far gone from the early evening, why not take children or grandchildren out with you? Let them catch fireflies in a jar, like captured meteors to take their fancy. Try the words of May Justus: “One night a little firefly, Was looking at a star, And said – but no one heard him – “I wonder what you are.” Then, eager for adventure, And brave as he could be, He trimmed his little lantern, And flew away to see!”

Even if you don’t take such fanciful notions to viewing a meteor shower, there’s still no harm enjoying a pleasant summer evening outdoors and adding to your scientific studies. For the most part, activity will take place in the south/southeast, so face in that general direction. As always, around midnight is a preferable time to begin – but there could always be early arrivals. Make your evening comfortable by bringing a blanket to lay on, or a reclining chair. Little things like a thermos of lemonade, cookies, insect repellent and binoculars are always welcome. If you live near city lights, why not make it a special event and take a drive to the countryside? And take along the words of Melville: “Of thee we think, in a ring we link; To the shearer of ocean’s fleece we drink, And the Meteor rolling home.”

[/caption]Greetings, fellow SkyWatchers! Now that the Moon is gone from the early evening skies and I’m back from that soul vacation, tracing my way across the constellations it’s time to break out binoculars and telescopes and enjoy some of the summer’s finest globular clusters – both easy and challenging. For everyone, it’s also time to get back in our atmosphere with drops of Jupiter in our hair and check out the Mighty Jove as it smokes up the sky. Are you ready to dance?

Friday, July 25 – Today in 1971, Apollo 15 was launched on its way to the Moon, and tonight we’ll launch our way north to the Mighty Hercules for a look at another globular study – M92. Although in a relatively open field for starhoppers, it’s not too hard to find if you can imagine it as the apex of a triangle with the northern keystone stars – Eta and Pi – as the base (RA 17 17 07 Dec +43 08 11).

At near magnitude 6, Class IV M92 was discovered by Johann Bode in 1777 and cataloged as Bode 76. Independently recovered by Messier in 1781 and resolved by Herschel in 1783, this bright, compact globular is around 26,700 light-years away and is about 12 to 14 billion years old. It contains 14 RR Lyrae variables among its 330,000 stars and also a very rare eclipsing binary. Viewable unaided under the right conditions and very impressive in even small binoculars, M92 is a true delight to even the smallest of telescopes. It has a very bright and unresolvable core with many outlying stars that are easily revealed. Larger scopes will appreciate its fiery appearance!

Now let’s hop south to Beta Ophiuchi to have a look at NGC 6426 about a fingerwidth south (RA 17 44 54 Dec +-3 10 12). There’s a very good reason why you’ll want to at least try with Herschel II.587. Discovered by Sir William in 1786, this 11th magnitude Class IX globular looks destroyed in comparison to M92. At 67,500 light-years away, it is more than twice the distance from us as M92! Residing 47,600 light-years from the galactic center, NGC 6426 contains 15 RR Lyrae variables (three of which are newly-discovered), and is the most metal-poor globular known. So what’s the relation to M92? It’s even a little bit older!

Forget about finding this one in binoculars and very small telescopes. For the mid-sized scope you’ll find it conveniently located about halfway between Beta and Gamma Ophiuchi – but it’s not easy. Faint and diffuse, a large telescope is required to begin resolution.

Saturday, July 26– For hardcore observers, tonight’s globular cluster study will require at least a mid-aperture telescope, because we’re staying up a bit later to go for a pair that can be seen in the same low power field – NGC 6522 and NGC 6528. You will find them easily at low power just a breath northwest of Gamma Sagittarii (Al Nasl), or the tip of the “teapot’s” spout. Once located, switch to higher power to keep the light of Gamma out of the field and let’s do some studying.

The brighter, and slightly larger, of the pair to the northeast is Class VI NGC 6522 (RA 18 03 34 Dec 30 02 02). Note its level of concentration compared to Class V NGC 6528 (RA 18 04 49 Dec 30 03 20). Both are located around 2,000 light-years from the galactic center, and are seen through a very special area of the sky known as “Baade’s Window” – one of the few areas toward our galaxy’s core region not obscured by dark dust. While they are similar in concentration, distance, etc., NGC 6522 has a slight amount of resolution toward its edges while NGC 6528 appears more random.

Both NGC 6522 and NGC 6528 were discovered by Sir William Herschel on the same night 1784 and both are the same distance from the galaxy’s nucleus. But there the similarities end: NGC 6522 has an intermediate metallicity. At its core, the red giants have been depleted – stripped tidally by evolving blue stragglers. It is possible that core collapse has already occurred. NGC 6528, however, contains one of the highest metal contents of any known globular cluster collected in its bulging core!

Now, let’s go kill our night vision and have a look at Jupiter! During the course of the evening of July 26-27, several events will happen – including eclipses and transits. For viewers in the United States eastern time zone, look for the Great Red Spot to appear on the meridian at around 10:48 p.m. While it’s difficult to make out the faint contrast of this most popular of all jovian features, take the opportunity to experiment with color filters if you have them. Even wearing sunglasses can sometimes produce surprising results!

Sunday, July 27 – Today in 1892, a very special astronomer was born – Sir George Biddell Airy. Does that name sound familiar? Anyone who uses a refractor understands the properties of the “Airy disc” as first outlined in his paper “On the Diffraction of an Object-Glass with Circular Aperture.” But, Sir George achieved a bit more: As Astronomer Royal from 1835 to 1881, his tireless devotion to planetary study led to the discovery by P. A. Hansen of two new irregularities in the moon’s motion. Not enough? Airy’s calculations also determined the mean density of the Earth. More? Then thank Sir George for giving us Greenwich Mean Time!

Are you still having no luck in finding a deep-space object? Then how about one that’s simple to locate for all optics. All you have to know is Antares and go west…

Just slightly more than a degree away you’ll find a major globular cluster perfectly suited for every size telescope and binoculars – M4 (RA 16 23 35 Dec 26 31 31). This 5th magnitude Class IX cluster can even be spotted unaided from a dark location! In 1746 Philippe Loys de Chéseaux happened upon this 7200 light-year distant beauty – one of the nearest to us. It was also included in Lacaille’s catalog as object I.9 and noted by Messier in 1764. Much to Charles’ credit, he was the first to resolve it!

As one of the loosest globular clusters, M4 would be tremendous if we were not looking at it through a heavy cloud of interstellar dust. To binoculars, it is easy to pick out a very round, diffuse patch – yet it will begin resolution with even a small telescope. Large telescopes will also easily see a central “bar” of stellar concentration across M4’s core region, which was first noted by Herschel.

As an object of scientific study, the first millisecond pulsar was discovered within M4 in 1987 – one which spins 10 times faster than the Crab Nebula pulsar. Photographed by the Hubble Space Telescope in 1995, M4 was found to contain white dwarf stars – the oldest in our galaxy – with a planet orbiting one of them! A little more than twice the size of Jupiter, this planet is believed to be as old as the cluster itself. At 13 billion years, it would be three times the age of the Sol system!

Have a great weekend….

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This story has been spreading like wildfire across the internet, as well as other news sources, which is not surprising given the topic. In a radio interview in the UK, and in a subsequent article in the Daily Register, former Apollo astronaut Edgar Mitchell said he believes there is life on other planets. OK, that’s not much of a bombshell. But then he went on to say that aliens have visited Earth, and our governments have been covering it up. That was the shocker. Mitchell said he was “privileged enough to be in on the fact that we’ve been visited on this planet and the U.F.O. phenomena is real.” While he didn’t offer any real facts or say that he has actually seen aliens, he said big organizations will soon be offering full disclosure. NASA officials responded to Mitchell’s comments fairly politely with this comment: “NASA does not track UFOs. NASA is not involved in any sort of cover up about alien life on this planet or anywhere in the universe. Dr. Mitchell is a great American, but we do not share his opinions on this issue.”

Mitchell was a member of Apollo 14, and was the sixth man to walk on the moon. While he didn’t offer any real proof of his claims, he does seemingly have credentials. However, he alone among the Apollo astronauts makes these types of claims, and has been saying things like this for quite some time. He said on the way home from the moon he had a “transformational, transcendental experience.” After his flight he started the Institute of Noetic Sciences, which “conducts and sponsors leading-edge research into the potentials and powers of consciousness.”

There was another interesting statement by Mitchell during this interview: “There’s more nonsense out there about this than there is real knowledge.”

Of course, the UFO folks have glommed onto these latest statements by Mitchell, but here’s what some of the more reputable news sites have been saying:

New York Times Blog: “While Mr. Mitchell, 77, is certainly entitled to his own views on the issue, the rest of us may need to wait for something more convincing.”

Huffington Post: “Mitchell, a member of the Apollo 14 team, has long held these beliefs despite the fact that he himself has never seen neither an alien or a U.F.O.”

NASA Watch’s Keith Cowing: “I assume you have proof to back up your extraterrestrial conspiracy mongering, Ed.”

Robert Pearlman, the editor of CollectSpace, wrote the following on an online forum:

Based on the nine minute call, it (a) doesn’t seem to be anything tremendously different from prior comments and writings by Dr. Mitchell, and (b) he isn’t actually claiming first-hand knowledge but rather repeating what he was told by others. It is no secret that Dr. Mitchell’s Noetic Science Institute attracts those that believe in extraterrestrials and that he has attended numerous conferences where they have been on the agenda for discussion, thus what he says here is of little surprise (and some might argue, consequence).

Irene Klotz from Discovery interviewed Mitchell after his UK radio interview and here’s an excerpt:

Irene Klotz: I wanted to ask you if there was anything about the radio interview you did that was different from what you’ve said in the past.

Edgar Mitchell: No, there’s nothing different. Several of (the reports of the interview) that I’ve seen come around have some flaws in them. Some of the reports pushed it or spun it incorrectly. NASA had nothing to do with anything I’ve done. I wasn’t briefed by NASA. There haven’t been any sightings as a result of my flight service there, so if that part of it comes out on anything you’ve seen it is just totally wrong.

In this Discovery interview, and in previous interviews, Mitchell has not offered any definite proof of his claims, and said he’s only been “told by people who were utterly sworn to secrecy” about alien visits to Earth. Mitchell grew up in Roswell, New Mexico.

All in all, unless Mitchell can offer definitive proof, his claims will have to be put in the same class as anyone else that makes similar claims, despite his background. Even with the prevalence of cameras and video cameras among the general public and with an abundance of investigative news reporters out there (all wanting to break the news story of the millennium) still, no one has been able to produce credible proof of aliens visiting Earth.

As the Bad Astronomer Phil Plait has said repeatedly, the people constantly looking at the skies, professional and amateur astronomers, have made no claims of UFO’s or aliens visiting Earth. They know what they are looking at in the sky.

For a dose of reality, please see Phil’s take on UFO’s.