Astronaut Buzz Aldrin, the second man on the Moon.
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The 1st man on the moon was the Apollo 11 Commander Neil Armstrong, who made history on July 20, 1969.
The Apollo 11 mission consisted of Command Module Pilot Michael Collins, Lunar Module Pilot Buzz Aldrin and Commander Neil Armstrong. The mission launched atop a Saturn V rocket on July 16, 1969. After a 4 day journey from the Earth to the Moon, the lunar module detached from the command module and landed on the surface of the Moon in the southern Sea of Tranquility.
The crew remained inside the module for 6 and a half hours, preparing to make their exit onto the lunar surface. And then Neil Armstrong descended the ladder from the lunar module and onto the lunar surface. The first words spoken by the first man on the Moon were, “that’s one small step for (a) man, one giant leap for mankind.”
Buzz Aldrin followed Armstrong, and the two remained on the surface of the Moon for 2.5 hours, taking photographs, collecting rocks, drilling samples, and placing scientific experiments. They they gathered up all their samples, stowed them in the lunar module, and left some souvenirs on the surface of the Moon, like an American flag, Apollo 1 mission patch, and commemorative plaque. They launched again and returned to Earth on July 24.
After the 1st man on the Moon, Neil Armstrong, there were a total of 12 astronauts to walk on the surface of the Moon.
Want to experience what it might have been like to be the first man on the Moon? Here’s a movie review of Fly Me to the Moon.
Of course, NASA has a tremendous amount of information about Apollo 11. Here’s the NASA history page about Apollo 11. And here’s a page that was put together for the 30th anniversary of the first man on the Moon.
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The total surface area of the Moon is 37.9 million square kilometers, or 14.6 million square miles.
Need some context? The surface area of the Earth is 510 million square kilometers. In other words, the total surface area of the Moon is only 7.4% the surface area of the Earth. If you could unwrap the Moon and lay it out flat on the Earth, it wouldn’t fill up Asia, which has an area of 44.4 million square kilometers.
The pulsar lies in the CTA 1 supernova remnant in Cepheus. Credit: NASA/S. Pineault, DRAO
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NASA’s Fermi Gamma-ray Space Telescope discovered the first pulsar that beams only in gamma rays. A pulsar is a rapidly spinning neutron star, the crushed core left behind when a massive sun explodes. Astronomers have cataloged nearly 1,800 pulsars. Although most were found through their pulses at radio wavelengths, some of these objects also beam energy in other forms, including visible light and X-rays. However, this new object only pulses at gamma-ray energies. “This is the first example of a new class of pulsars that will give us fundamental insights into how these collapsed stars work,” said Stanford University’s Peter Michelson, principal investigator for Fermi’s Large Area Telescope.
The gamma-ray-only pulsar lies within a supernova remnant known as CTA 1, which is located about 4,600 light-years away in the constellation Cepheus. Its lighthouse-like beam sweeps Earth’s way every 316.86 milliseconds. The pulsar, which formed about 10,000 years ago, emits 1,000 times the energy of our sun.
“We think the region that emits the pulsed gamma rays is broader than that responsible for pulses of lower-energy radiation,” explained team member Alice Harding at NASA’s Goddard Space Flight Center in Greenbelt, Md. “The radio beam probably never swings toward Earth, so we never see it. But the wider gamma-ray beam does sweep our way.”
Scientists think CTA 1 is only the first of a large population of similar objects.
“The Large Area Telescope provides us with a unique probe of the galaxy’s pulsar population, revealing objects we would not otherwise even know exist,” says Fermi project scientist Steve Ritz, also at Goddard.
Fermi’s Large Area Telescope scans the entire sky every three hours and detects photons with energies ranging from 20 million to more than 300 billion times the energy of visible light. The instrument sees about one gamma ray every minute from CTA 1, enough for scientists to piece together the neutron star’s pulsing behavior, its rotation period, and the rate at which it is slowing down.
The pulsar in CTA 1 is not located at the center of the remnant’s expanding gaseous shell. Supernova explosions can be asymmetrical, often imparting a “kick” that sends the neutron star careening through space. Based on the remnant’s age and the pulsar’s distance from its center, astronomers believe the neutron star is moving at about a million miles per hour — a typical speed.
Artist's impression of a young star with surrounding disk of dust (ESO/L. Calçada)
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Understanding how stars form is critical to astronomers. If we can gain a better understanding of how intermediate-size infant stars grow, we can begin to answer some of the most perplexing questions hanging over the evolution of our own Solar System. Unfortunately, the nearest star forming regions are about 500 light years away, meaning that astronomers cannot simply use traditional optical telescopes to peer into star-forming disks of gas and dust. So, researchers working with the European Southern Observatory (ESO) are combining high resolution spectroscopic and interferometry observations to give the most detailed view yet of infant stars eating away at their proto-planetary disk, blasting out violent stellar winds as they do so…
It sounds like baby stars are very much like their human counterparts. They need a conveyor belt of food supplying their development and they blast huge amounts of waste back out in the form of gas. These findings come from researchers using the ESO’s Very Large Telescope Interferometer (VLTI), giving us milli-arcsecond resolution when focusing on these star-forming regions. The detail this provides is equivalent to studying the period (‘full stop’ as I prefer to call it) at the end of this sentence at a distance of 50 km (31 miles).
This high resolution is achieved by combining the light from two or more telescopes separated by a certain distance. This distance is known as the “baseline,” and interferometers such as the VLTI have a large baseline (of up to 200 metres), simulating a telescope diameter equivalent to this distance. However, the VLTI now has another trick up its sleeve. The AMBER spectrometer can be used in conjunction with the interferometer observations to give a more complete view of these feeding stars, probing deep into the spectrum of light being emitted from the region.
“So far interferometry has mostly been used to probe the dust that closely surrounds young stars. But dust is only one percent of the total mass of the discs. Their main component is gas, and its distribution may define the final architecture of planetary systems that are still forming.” – Eric Tatulli, co-leader of the VLTI international collaboration from Grenoble, France.
The Herbig Ae/Be star R Coronae Australis, a young intermediate-size star (2MASS)Using the combined power of the VLTI and AMBER instrument, astronomers have been able to map this gas surrounding six stars belonging to the Herbig Ae/Be family. These particular stars are typically less than 10 million years old and a few times the mass of our Sun. They are very active stars in the process of forming, dragging huge amounts of material from a surrounding disk of dust.
Until now, astronomers have not been able to detect gas emission from young stars feeding on their stellar disks, thereby keeping the physical processes acting close to the star a mystery.
“Astronomers had very different ideas about the physical processes that have been traced by the gas. By combining spectroscopy and interferometry, the VLTI has given us the opportunity to distinguish between the physical mechanisms responsible for the observed gas emission,” says co-leader Stefan Kraus from Bonn in Germany. In two of the Herbig Ae/Be stars, there is evidence for a large quantity of dust falling into them, thereby increasing their masses. In four cases, there is evidence for a strong stellar wind, forming an extended stellar gas outflow.
The VLTI observations also reveal dust from the surrounding disk is much closer than one would expect. Usually there is a cut-off distance for dust location as the stars heat will cause it to vaporize. However, it would appear in one case that gas between the star and dusty disk shields the dust from evaporating; the gas acts as a radiation-block, allowing the dust to extend closer to the star.
“Future observations using VLTI spectro-interferometry will allow us to determine both the spatial distribution and motion of the gas, and might reveal whether the observed line emission is caused by a jet launched from the disc or by a stellar wind“, Kraus added.
These phenomenal observations of star-forming dust disks and gas emission, 500 light years away, open up a new kind of high-resolution astronomy. This will help us understand how our Sun fed off its surrounding disk of dust, eventually forming the planets and, ultimately, how life on Earth was possible…
WASP-12b orbits so close to its star that it is heated to a record-breaking 2250°C (ESA/C Carreau)
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Planets approximately the size of Jupiter orbiting close to their star in other systems are often referred to as “Hot Jupiters.” It would appear that a new classification is required: Very Hot and Very Fast Jupiters. WASP-12b is an exoplanet, about 50% more massive than Jupiter, orbiting a star (imaginatively called WASP-12) over 800 light years away, but it isn’t any ordinary exoplanet. It orbits its host star 1/40th of the distance at which the Earth orbits the Sun and it takes a breathtaking one day to complete one orbit. As a consequence, its host star heats WASP-12b to record-breaking temperatures; the planet is being toasted up to 2250 °C. For an exoplanet of this size, to be orbiting so close to a star has caused a stir amongst planet hunters. WASP-12b is and oddity, there’s nothing else like it… so far.
This new discovery originates from the UK’s Wide Area Search for Planets, a.k.a. “SuperWASP”. SuperWASP is a robotic system surveying both hemispheres, consisting of two observatories (one in the Canary Islands, off the coast of Africa, called SuperWASP-North; one in South Africa called SuperWASP-South) with eight cameras in both. The north and south observatories are on the look out for extrasolar planets, but rather than focusing on one star and seeing whether it wobbles (thereby giving away the presence of the gravitational pull of an orbiting planet), SuperWASP looks out for the periodic dimming of stars as their companion planets pass in front of them. Since it began operations in 2004, the two observatories have found 15 transiting exoplanets (as of April 2008).
Artist illustration of the planet orbiting the sun-like star HD 149026 (U.C. Santa Cruz)Now, astronomers have focused their attentions on one rather strange exoplanet. When WASP-12b was first seen by the robotic planet spotters, researchers knew they were on to something special. The speed at which WASP-12b was transiting its host star (WASP-12) indicated that it had an orbital period of only 1.1 (Earth) days. This therefore meant that it had to be located very close to the star. This meant that it was going to be hot. Very, very hot in fact. Early estimates put WASP-12b’s surface temperature into the record-breaking range, possibly challenging the calculated temperature of HD 149026b, an exoplanet some 257 light-years away in the constellation of Hercules, with an estimated temperature of 2050°C. WASP-12b has an estimated surface temperature of 2250°C – that’s half as hot as the temperature of our Sun’s photosphere, and approximately the same temperature as many Class M stars.
Although impressive, there may be hotter “Hot Jupiters” out there, but the orbital velocity of WASP-12b will be a tougher record to beat. To date, most Jupiter-sized exoplanets have orbital periods of a few days, which led astronomers to believe there was some planetary mechanism preventing these planets from migrating very close to their host stars. Although Jupiter-like planets will have formed further away from their stars, they drift closer as they evolve until they settle into a stable orbit. Usually these orbits are located far away from the star, but WASP-12b obviously didn’t read the rule book before it set up home in its stellar oven.
“When the planets form and migrate inward, something is causing them to stop and preferentially stop with a period of three days,” said Leslie Hebb of the University of St Andrews, UK. “I was surprised that the period could be so much shorter.”
So WASP-12b has a strange orbit, making it orbit very fast, causing it to be heated to astounding temperatures. But the strangeness doesn’t stop there. It has a diameter 1.8 times that of Jupiter, far bigger than gas giants are thought to grow. However, the extreme temperatures WASP-12b is experiencing may explain its obesity problem – the star could be causing the planet to “puff up,” making the gas giant less dense, but blowing it 80% larger than Jupiter proportions.
Now, SuperWASP researchers hope to probe the planetary system for UV light radiating from the exoplanet, possibly showing evidence that WASP-12b’s atmosphere is undergoing aggressive stripping or evaporation at such close proximity to the host star.
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The mass of the Moon is 7.347 x 1022 kg.
That sounds like a large number, and I suppose it is compared to the mass of a single person, a car or even a building. But you’ve got to keep it in context. The mass of the Moon is only 1.2% the mass of the Earth. In other words, you would need 81 objects with the mass of the Moon to match the mass of the Earth.
The diameter of the Moon is only about 1/4 the diameter of the Earth, so it might seem like the mass of the Moon is strangely low. And you would be right. The key is the Moon’s low density. It has a density of only 3.3 g/cm3. This is almost half the density of Earth.
Astronomers think that a Mars-sized object crashed into the Earth about 100 million years after the Earth formed. The huge cloud of ejected debris coalesced into the Moon, which still orbits us today. The Moon has a lower density because the impact gouged out the outer crust and mantle, and didn’t eject so much of the Earth’s iron core.
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A lunar day is the length of time it takes for the Moon to make one complete rotation on its axis compared to the Sun. This is important because the Moon is tidally locked with respect to the Earth. So it always points the same face towards the Earth as it goes around the planet. So, how long is a day on the Moon?
The lunar day lasts 29 days, 12 hours and 44 minutes. And this the same time it takes for the Moon to orbit around the Earth.
With respect to the background stars, however, the Moon only takes 27 days and 7 hours for the sky to completely rotate back to its original position.
So why is there a difference?
As the Earth and Moon are orbiting around the Sun, they complete a circle over the course of the year. Each time the Moon goes around the Earth, it needs to go a little further to get the Sun back into the same position.
If you ever get the opportunity to stand on the surface of the Moon, and look at the Earth, our planet would always remain in the exact same position in the sky. The Sun, on the other hand, will still rise, move across the sky and then set. Of course, an average day will last 29 days, 12 hours and 44 minutes until the Sun returns to the same position in the sky.
Astronomers say that the Moon is tidally locked to the Earth. At some point in the distant past, the Moon rotated more rapidly than it currently does. The Earth’s gravity caused part of the Moon to bulge out. The pull of gravity caused the rotation of the Moon to slow down until this bulge was pointing directly at the Earth. At this point, the Moon was tidally locked to the Earth; this is why it shows the same face to us.
And it’s also why a lunar day lasts the same as it takes the Moon to go around the Earth.
One of the most famous pictures taken during the space age is Earthrise, captured by the Apollo 8 astronauts. Here’s an article about it, and here’s an update from the Japanese Kaguya spacecraft.
A NASA astronaut on the lunar surface (credit: NASA)
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Are you feeling heavy? Maybe it’s time to go to the Moon, where you’ll experience much less gravity. Since the Moon is smaller, and has much less mass, it pulls with less gravity. In fact, if you could stand on the surface of the Moon, you would experience only 17% the force of gravity that you would experience on Earth. Gravity on the Moon is much less.
Just to give you an example, let’s say that you weighed 100 kg on Earth. If you stood on the Moon, and then onto your bathroom scale your weight would only be 17 kg. With gravity on the Moon so low, you would be able to jump much higher. If you can jump 30 cm on Earth, you would be able to jump almost 2 meters straight up into the air. And you would be able to fall much further on the Moon. If you jumped off the roof of your house, it would only feel like you jumped off a table. You would be able to throw a ball 6 times further, hit a golf ball 6 times further… you get the idea.
When the Apollo astronauts first walked on the surface of the Moon, they needed to learn how to walk differently in the Moon’s gravity. That’s why the astronauts do a funny hopping run as they move across the surface of the Moon. If they tried to take normal steps, they would fly up into the air to far and fall over – that did happen a few times.
One last, fascinating idea. The pull of gravity on the Moon is so low that you could actually fly with wings attached to your arms (as long as you were inside an enclosed dome filled with air at the Earth’s atmospheric pressure. Wouldn’t it be great to be able to fly around like a bird?
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Have you ever heard that there’s a special time of the year when you’ll be able to see Mars in the sky so big that it looks like a double Moon? You might have gotten this as an email from a friend or family member. Here’s an example of the email.
The Red Planet is about to be spectacular! This month and next, Earth is catching up with Mars in an encounter that will culminate in the closest approach between the two planets in recorded history. The next time Mars may come this close is in 2287. Due to the way Jupiter’s gravity tugs on Mars and perturbs its orbit, astronomers can only be certain that Mars has not come this close to Earth in the Last 5,000 years, but it may be as long as 60,000 years before it happens again.
The encounter will culminate on August 27th when Mars comes to within 34,649,589 miles of Earth and will be (next to the moon) the brightest object in the night sky. It will attain a magnitude of -2.9 and will appear 25.11 arc seconds wide. At a modest 75-power magnification
Mars will look as large as the full moon to the naked eye. By the end of August when the two planets are closest, Mars will rise at nightfall and reach its highest point in the sky at 12:30 a.m. That’s pretty convenient to see something that no human being has seen in recorded history. So, mark your calendar at the beginning of August to see Mars grow progressively brighter and brighter throughout the month. Share this with your children and grandchildren. NO ONE ALIVE TODAY WILL EVER SEE THIS AGAIN
Are we going to get a chance to see a double Moon? I’m sorry, but this is a complete hoax and Internet myth. We’ve written many times about this on Universe Today. Here’s a link to a more complete article.
Each time this email hoax goes around the Internet, it doesn’t mention the year. It only says August 27th, but it doesn’t say what year. In reality, this email first started in 2003. But because the email doesn’t have a year, it keeps coming around year after year. There wasn’t a double moon back in 2003. And there won’t be one this year – whenever you’re reading this.
Mars did make a close approach back in 2003, but it was only slightly closer than it gets any other year that it makes a close approach to the Earth. It came within 34.6 million km. But if you don’t understand how far away that is, it’s hard to see that it can’t be anywhere near as close or big as the Moon. Mars looked like a bright red star in the sky. But nothing like a double moon.
What this email is trying to say is that if you put your eye to the telescope and looked at Mars at 75 power magnification, it would look about the same size as the Moon looks with the unaided eye. In other words, you’d see a double moon if you could somehow look at both at the same time – but you can’t.
I hope this helps clear up the double moon myth.
We’ve tackled this myth many times in the past. Here’s the one we did in 2006, 2007, and 2008.
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The astronomical symbol for the Moon is easy to recognize: it’s a crescent moon. Both the crescent and decrescent moon symbols are used to represent the Moon in astronomy, astrology and alchemy.
When the crescent is on the right, this is the first phase of the Moon, as seen by the northern hemisphere. Think about that for a second, when you’re standing in the southern hemisphere, your view of the Moon is reversed. So from a southern perspective, the crescent will be on the left. But for people in the northern hemisphere, when the crescent is on the right, it’s the first quarter, just after the new moon. And when the crescent is on the left, it’s in the last quarter, just before the new Moon.
Calendars often use a different set of symbols for the Moon to designate the different phases.
Full Moon
First Quarter
Last Quarter
New Moon
This is the same symbol used for the Moon in astrology, and represents silver in alchemy.
Want to know more symbols, here’s the symbol for the Sun, and here’s the symbol for the Earth.
Here’s more information about the Moon symbol from symbols.com.
Full Moon 
First Quarter
Last Quarter
New Moon