What Does it Take to Be an Astronaut?

What does it take to have the “Right Stuff” to become an Astronaut?

Are you an overachiever? Are you working on multiple PhDs in obscure and difficult topics? Can you speak multiple languages, including alienese? Do you suspect, if handed the controls, you could complete the Kessel Run in fewer parsecs than Han Solo?

If you said yes to any of these questions you might want to consider becoming an astronaut. In fact, if you’re an American citizen, there’s never been a better time to see if you’ve got the right stuff. NASA has opened up their astronaut corps to the few, the proud, the willing to get motion sickness in zero gravity. To boldly vomit where few have vomited before.

In the olden days, you either had to be a chimpanzee or an Air Force test pilot to be allowed to take the controls of a genuine NASA rocket and break free from the surly chains of gravity. When NASA finally upgraded its astronaut corps from chimps to humans in the 1950s to begin the Mercury program, they decided they’d only allow test pilots to apply for the first missions.

To fit in the cramped cabin, you had to physically be no taller than 180 cm (5’ 11”), and weigh no more than 82 kg (180 pounds). You needed to have book smarts, too. Astronaut candidates needed at least a bachelor’s degree or the equivalent, but still be under 40 years old. But most importantly, you had to be a test pilot with at least 1,500 hours of flying time and the ability to fly jets.

If you didn’t have hours behind the stick, piloting the most insane flying machines dreamt up by those nutty scientists, well then you didn’t have the right stuff.

Those qualifications continued through the Gemini and Apollo program, although, they relaxed them somewhat, allowing younger astronauts, and those with less flight time. In the recruitment of astronauts in 1965, they allowed a new class of scientist-astronauts; folks with science degrees and no flight time. The most famous of these was Jack Schmitt, a geologist who walked on the Moon with Apollo 17.

NASA now understands that they need astronauts with a wide range of space-based skills, and not just a bunch of test pilots. There are two kinds of people who get to go to space: pilots and mission specialists.

STS-134 commander Mark Kelly strides across the runway of the Shuttle Landing Facility. Credit: Michael Deep, for Universe Today.
STS-134 commander Mark Kelly strides across the runway of the Shuttle Landing Facility. Credit: Michael Deep, for Universe Today.

The first category are the commanders and pilot astronauts – the folks who actually fly the spacecraft. They’re the ones with thousands of hours behind the stick of a modern jet, the more cockamamie the better.

To be qualified as a pilot astronaut, you need to have at least 1,000 hours of pilot-in-command time in a jet aircraft. You need to be healthy, with normal blood pressure, good vision and a height between 158 – 191 cm (62 and 75 inches). There are no longer any age restrictions, so astronauts have been selected between 26 and 46 years old.

You need a degree in some kind of space-related science, like engineering, mathematics, biological science and physical science. But that’s a minimum. You really want to have an advanced degree, or even multiple degrees. So, if you’re a healthy, eagle-eyed test pilot with a few advanced degrees, you should apply.

The other category is the mission specialists. These are the astronauts with specialties that will come into play on a space mission. For example: doctors, engineers, particle physicists, xenobiologists, alien translators, droid mechanics, etc. Since you won’t be required to fly the spacecraft, test pilot experience isn’t necessary, but you’ll need to have the same physical health as the pilot astronaut.

Nicole Stott, STS-133 mission specialist, is pictured in the Cupola of the International Space Station. Credit: NASA
Nicole Stott, STS-133 mission specialist, is pictured in the Cupola of the International Space Station. Credit: NASA

The main difference is that you’ll need to have one or multiple advanced degrees in engineering, science or math. The more degrees, and the more advanced they are, the better. Gotta collect them all.

I mentioned two kinds of astronauts, but there’s actually a third – the payload specialist. These were the astronauts who went to space during the shuttle era to support a specific mission. Priority was given to qualified NASA astronauts, but this was also how foreign astronauts like Canada’s Marc Garneau got a chance to fly in space.

Are you intrigued and thinking you might want to throw your name in the helmet? Want to know what being an astronaut pays? A starting astronaut can make $66,000 per year, while a senior one can earn $145,000 per year. Not bad at all, and the view from your office is spectacular.

So, if you’re a US citizen, you meet the qualifications, and you’d like to fly to space, you should apply during this latest call for candidates. And if you don’t think you make the cut, go ahead and wrap up those PhDs, as there’ll be another astronaut selection in a few years.

And if you do apply and don’t make the cut this time around, don’t despair. From the astronauts I’ve talked to, sometimes it takes a few applications before you get accepted. Persistence pays off.

Well, are you going to sign up and become an astronaut? Where do you think your mission will go? Tell us in the comments below.

Don’t Miss the Geminids this Weekend, Best Meteor Shower of the Year

Wouldn’t it be nice if a meteor shower peaked on a weekend instead of 3 a.m. Monday morning? Maybe even showed good activity in the evening hours, so we could get our fill and still get to bed at a decent hour. Wait a minute – this year’s Geminids will do exactly that!

Before moonrise this Saturday night December 13th, the Geminids should put on a sweet display. The radiant of the shower lies near the bright pair of stars, Castor and Pollux. Source: Stellarium
Before moonrise this Saturday night December 13th, the Geminids should put on a sweet display. The radiant of the shower lies near the bright pair of stars, Castor and Pollux. Source: Stellarium

What’s more, since the return of this rich and reliable annual meteor shower occurs around 6 a.m. (CST) on Sunday December 14th, both Saturday and Sunday nights will be equally good for meteor watching. After the Perseids took a battering from the Moon last August, the Geminids will provide the best meteor display of 2014.  They do anyway! The shower’s been strengthening in recent years and now surpasses every major shower of the year.

The official literature touts a rate of 120 meteors per hour visible from a dark sky site, but I’ve found 60-80 per hour a more realistic expectation. Either way, what’s to complain?

The third quarter Moon rises around midnight Saturday and 1 a.m. on Monday morning. Normally, moonlight would be cause for concern, but unlike many meteor showers the Geminids put on a decent show before midnight. The radiant, the location in the sky from which the meteors will appear to stream, will be well up in the east by 9:30 p.m. local time. That’s a good 2-3 hours of meteor awesomeness before moonrise.

The author tries his best to enjoys this year's moon-drenched Perseids from the "astro recliner". Credit: Bob King
The author takes in this year’s moon-drenched Perseids in comfort.

Shower watching is a total blast because it’s so simple. Your only task is to dress warmly and get comfortable in a reclining chair aware from the unholy glare of unshielded lighting. The rest is looking up. Geminid meteors will flash anywhere in the sky, so picking a direction to watch the shower isn’t critical. I usually face east or southeast for the bonus view of Orion lumbering up from the horizon.

Bring your camera, too. I use a moderately wide angle lens (24-35mm) at f/2.8 (widest setting), set my ISO to  800 or 1600 and make 30-second exposures. The more photos you take, the better chance of capturing a meteor. You can also automate the process by hooking up a relatively inexpensive intervalometer  to your camera and have it take the pictures for you.

As you ease back and let the night pass, you’ll see other meteors unrelated to the shower, too. Called sporadics, they trickle in at the rate of  2-5 an hour. You can always tell a Geminid from an interloper because its path traces back to the radiant. Sporadics drop down from any direction.

A Geminid fireball brighter than Venus streaks across the sky above New Mexico on Dec. 14, 2011. It was captured by an all-sky camera. Before disintegrating in the atmosphere the meteoroid was about 1/2 inch across. Credit: Marshall Space Flight Center, Meteoroid Environments Office, Bill Cooke
Captured by an all-sky camera, a Geminid fireball brighter than Venus streaks across the sky above New Mexico on Dec. 14, 2011. Before disintegrating in the atmosphere the meteoroid was about 1/2 inch across. Credit: Marshall Space Flight Center, Meteoroid Environments Office, Bill Cooke

Geminid meteors immolate in Earth’s atmosphere at a moderate speed compared to some showers – 22 miles per second (35 km/sec) – and often flare brightly. Green, red, blue, white and yellow colors have been recorded, making the shower one of the more colorful. Most interesting, the meteoroid stream appears to be sorted according to size with faint, telescopic meteors maxing out a day before the naked eye peak. Larger particles continue to produce unusually bright meteors up to a few days after maximum.

Most meteor showers are the offspring of comets. Dust liberated from vaporizing ice gets pushed back by the pressure of sunlight to form a tail and fans out over the comet’s orbital path. When Earth’s orbit intersects a ribbon of this debris, sand and gravel-sized bits of rock crash into our atmosphere at high speed and burn up in multiple flashes of meteoric light.

Phaethon sprouts a tail when close to the Sun seen in this image taken by NASA's STEREO Sun-observing spacecraft in 2012. Credit: Credit: Jewitt, Li, Agarwal /NASA/STEREO
Phaethon sprouts a tail (points southeast or to lower left) when close to the Sun in this image taken by NASA’s STEREO Sun-observing spacecraft in 2012. Credit: Credit: Jewitt, Li, Agarwal /NASA/STEREO

But the Geminids are a peculiar lot. Every year in mid-December, Earth crosses not a comet’s path but that of 3200 Phaethon (FAY-eh-thon), a 3.2 mile diameter (5.1 km)  asteroid. Phaethon’s elongated orbit brings it scorchingly close (13 million miles) to the Sun every 1.4 years. Normally a quiet, well-behaved asteroid, Phaethon brightened by a factor of two and was caught spewing jets of dust when nearest the Sun in 2009, 2010 and 2012. Apparently the intense heat solar heating either fractured the surface or heated rocks to the point of desiccation, creating enough dust to form temporary tails like a comet.

While it looks like an asteroid most of the time, Phaethon may really be a comet that’s still occasionally active. Periodic eruptions provide the fuel for the annual December show.

Most of us will head out Saturday or Sunday night and take in the shower for pure enjoyment, but if you’d like to share your observations and contribute a bit of knowledge to our understanding of the Geminids, consider reporting your meteor sightings to the International Meteor Organization. Here’s the link to get started.

And this just in … Italian astronomer Gianluca Masi will webcast the shower starting at 8 p.m. CST December 13th (2 a.m. UT Dec. 14) on his Virtual Telescope Project site.

Survival: Terrifying Moments in Space Flight

Space is a dangerous and sometimes fatal business, but happily there were moments where a situation happened and the astronauts were able to recover.

An example: today (March 16) in 1966, Neil Armstrong and Dave Scott were just starting the Gemini 8 mission. They latched on to an Agena target in the hopes of doing some docking maneuvers. Then the spacecraft started spinning inexplicably.


They undocked and found themselves tumbling once per second while still out of reach of ground stations. A thruster was stuck open. Quick-thinking Armstrong engaged the landing system and stabilized the spacecraft. This cut the mission short, but saved the astronauts’ lives.

Gemini 8's Agena target before a stuck thruster on the spacecraft put the astronauts in a terrifying tumble. Credit: NASA
Gemini 8’s Agena target before a stuck thruster on the spacecraft put the astronauts in a terrifying tumble. Credit: NASA

Here are some other scary moments that astronauts in space faced, and survived:

Friendship 7: False landing bag indicator (1962)

Astronaut John Glenn views stencilling used as a model to paint the words "Friendship 7" on his spacecraft. Credit: NASA
Astronaut John Glenn views stencilling used as a model to paint the words “Friendship 7” on his spacecraft. Credit: NASA

John Glenn was only the third American in space, so you can imagine the amount of media attention he received during his three-orbit flight. NASA received an indication that his landing bag had deployed while he was still in space. Friendship 7’s Mercury spacecraft had its landing cushion underneath the heat shield, so NASA feared it had ripped away. Officials eventually informed Glenn to keep his retrorocket package strapped to the spacecraft during re-entry, rather than jettisoning it, in the hopes the package would keep the heat shield on. Glenn arrived home safely. It turned out to be a false indicator.

Apollo 11: Empty fuel tank (1969)

Apollo 11's Eagle spacecraft, as seen from fellow spaceship Columbia. Credit: NASA
Apollo 11’s Eagle spacecraft, as seen from fellow spaceship Columbia. Credit: NASA

Shortly after Neil Armstrong announced “Houston, Tranquility Base, here, the Eagle has landed” during Apollo 11, capsule communicator Charlie Duke answered, “Roger, Tranquility. We copy you on the ground. You got a bunch of guys about to turn blue. We’re breathing again. Thanks a lot.” They weren’t holding their breath just because it was the first landing on the moon; Armstrong was navigating a spacecraft that was almost out of fuel. The spacecraft Eagle overshot its landing and Armstrong did a series of maneuvers to put it on relatively flat ground. Accounts say he had less than 30 seconds of fuel when he landed on July 20, 1969.

Apollo 12: Lightning strike (1969)

Apollo 12's launch in 1969, moments before the rocket was struck by lightning. Credit: NASA
Apollo 12’s launch in 1969, moments before the rocket was struck by lightning. Credit: NASA

Moments after Apollo 12 headed from ground towards orbit, a lightning bolt hit the rocket and caused the spacecraft to go into what appeared to be a sort of zombie mode. The rocket was still flying, but the astronauts (and people on the ground) were unsure what to do. Scrambling, one controller suggested a command that essentially reset the spacecraft, and Apollo 12 was on its way. NASA did take some time to do some double-checking in orbit, to be sure, before carrying on with the rest of the mission. The agency also changed procedures about launching in stormy weather.

Apollo 13: Oxygen tank explosion (1970)

Evidence of the Apollo 13 explosion on the spacecraft Odyssey. Credit: NASA
Evidence of the Apollo 13 explosion on the service module. Credit: NASA

The astronauts of Apollo 13 performed a routine stir of the oxygen tanks on April 13, 1970. That’s when they felt the spacecraft shudder around them, and warning lights lit up. It turned out that an oxygen tank, damaged through a series of ground errors, had exploded in the service module that fed the spacecraft Odyssey, damaging some of its systems. The astronauts survived for days on minimal power in Aquarius, the healthy lunar module that was originally supposed to land on the moon. They arrived home exhausted and cold, but very much alive.

Apollo-Soyuz Test Project: Toxic vapours during landing (1975)

The Apollo command module used in the Apollo-Soyuz Test Project, during recovery. Credit: NASA
The Apollo command module used in the Apollo-Soyuz Test Project, during recovery. Credit: NASA

The Apollo-Soyuz Test Project was supposed to test out how well American and Russian systems (and people) would work together in space. Using an Apollo command module and a Russian Soyuz, astronauts and cosmonauts met in orbit and marked the first mission between the two nations. That almost ended in tragedy when the Americans returned to Earth and their spacecraft was inadvertently flooded with vapours from the thruster fuel. “I started to grunt-breathe to make sure I got pressure in my lungs to keep my head clear. I looked over at Vance [Brand] and he was just hanging in his straps. He was unconscious,” recalled commander Deke Slayton, in a NASA history book about the event. Slayton ensured the entire crew had oxygen masks, Brand revived quickly, and the mission ended shortly afterwards.

Mir: The fire (1997)

Jerry Linenger dons a mask during his mission on Mir in 1997. Credit: NASA
Jerry Linenger dons a mask during his mission on Mir in 1997. Credit: NASA

The crew on Mir was igniting a perchlorate canister for supplemental oxygen when it unexpectedly ignited. As they scrambled to put out the fire, NASA astronaut Jerry Linenger discovered at least one oxygen mask on board were malfunctioning as well. The crew managed to contain the fire quickly. Even though it affected life aboard the station for a while afterwards, the crew survived, did not need to evacuate, and helped NASA learn lessons that they still use aboard the International Space Station today.

STS-51F: Abort to orbit (1985)

STS-51F aborted to orbit during its launch. Credit: NASA
STS-51F aborted to orbit during its launch. Credit: NASA

The crew of space shuttle Challenger endured two aborts on this mission. The first one took place at T-3 seconds on July 12, when a coolant valve in one of the shuttle’s engines malfunctioned. NASA fixed the problem, only to face another abort situation shortly after liftoff on July 29. One of the engines shut down too early, forcing the crew to abort to orbit. The crew was able to carry on its mission, however, including many science experiments aboard Spacelab.

STS-114: Foam hitting Discovery (2005)

Discovery during STS-114, as seen from the International Space Station. CREDIT: NASA
Discovery during STS-114, as seen from the International Space Station. CREDIT: NASA

When Discovery lifted off in 2005, the fate of the entire shuttle program was resting upon its shoulders. NASA had implemented a series of fixes after the Columbia disaster of 2003, including redesigning the process that led to foam shedding off Columbia’s external tank and breaching the shuttle wing. Wayne Hale, a senior official in the shuttle program, later recalled his terror when he heard of more foam loss on Discovery: “I think that must have been the worst call of my life. Once earlier I had gotten a call that my child had been in an auto accident and was being taken to the hospital in an ambulance. That was a bad call. This was worse.” The foam, thankfully, struck nothing crucial and the crew survived. NASA later discovered the cracks in the foam are linked to changes in temperature the tank undergoes, and made more changes in time for a much more successful mission in 2006.

We’ve probably missed some scary moments in space, so which ones do you recall?

New NASA Gallery of Restored 1960s Project Gemini Photos


NASA has published a new online gallery of beautifully restored photographs from the historic Project Gemini of the 1960s, the second U.S. manned spaceflight program. The digitally remastered photos have been scanned from the original film, showing highlights of Project Gemini in beautifully enhanced colour and detail.

Project Gemini followed the initial Project Mercury program and was the predecessor for the ambitious Apollo missions to the Moon, with ten crewed flights from 1965-1966. It used a two-man spacecraft and tested new technologies and procedures for the later Apollo missions such as precision atmospheric reentry, Extra Vehicular Activity (spacewalking), fuel cells to generate electricity and water, perfect the rendezvous and docking process between two spacecraft, new techniques for propelling and maneuvering two docked spacecraft and long-term human spaceflight.

It featured the first spacewalk, the first rendezvous between two Gemini spacecraft, the first docking between a manned and unmanned vehicle, the first maneuver to change orbit and the first onboard computer.

Gemini VII's rendezvous with Gemini VI. Credit: NASA / JSC / Arizona State University

The photo gallery is part of the March to the Moon website archive, which also has restored photo galleries from the Mercury missions as well as background information on the missions, Quicktime video clips and links to additional resources.

Gemini’s New Filters Reveal the Beauty of Star Birth

About 2,000 light-years away, in the constellation of Cygnus (the Swan), lies Sharpless 2-106 (after Stewart Sharpless who put the catalog together in 1959), the birth-place of a star cluster-to-be.

Two recent image releases – by Subaru and Gemini – showcase their new filter sets and image capabilities; they also reveal the stunning beauty of the million-year-long process of the birth of a star.

Sharpless 2-106 (Gemini Observatory/AURA)

The filter set is part of the Gemini Multi-Object Spectrograph (GMOS) toolkit, and includes ones centered on the nebular lines of doubly ionized oxygen ([OIII] 499 nm), singly ionized sulfur ([SII] 672 nm), singly ionized helium (HeII 468nm), and hydrogen alpha (Hα 656 nm). The filters are all narrowband, and are also used to study planetary nebulae and excited gas in other galaxies.

The hourglass-shaped (bipolar) nebula in the new Gemini image is a stellar nursery made up of glowing gas, plasma, and light-scattering dust. The material shrouds a natal high-mass star thought to be mostly responsible for the hourglass shape of the nebula due to high-speed winds (more than 200 kilometers/second) which eject material from the forming star deep within. Research also indicates that many sub-stellar objects are forming within the cloud and may someday result in a cluster of 50 to 150 stars in this region.

The nebula’s physical dimensions are about 2 light-years long by 1/2 light-year across. It is thought that its central star could be up to 15 times the mass of our Sun. The star’s formation likely began no more than 100,000 years ago and eventually its light will break free of the enveloping cloud as it begins the relatively short life of a massive star.

For this Gemini image four colors were combined as follows: Violet – HeII filter; Blue – [SII] filter; Green – [OIII] filter; and Red – Hα filter.

Sharpless 2-106 (Copyright Subaru Telescope, National Astronomical Observatory of Japan. All rights reserved)

The Subaru Telescope image was made by combining images taken through three broadband near-infrared filters, J (1.25 micron), H (1.65 micron), and K’ (2.15 micron).

Sources: Gemini Observatory, NAOJ

Mysterious Alien Dust Hints at Violent Planet Formation

Image credit: Lynette Cook for Gemini Observatory/AURA

An artist’s rendition of colliding planets, the most likely explanation for the warm dust observed around HD 131488. Image credit: Lynette Cook for Gemini Observatory/AURA

Five-hundred light years away, worlds are colliding, and they’re made of nothing we’ve ever seen.

Last week at the 215th American Astronomical Society meeting, UCLA astronomers announced that they had found warm dust – evidence for the violent collision of rocky planets – around a star called HD 131488. The strange thing is, the composition of the dust has little in common with the composition of rocky bodies in any other known system.

“Typically, dust debris around other stars, or our own Sun, is of the olivine, pyroxene, or silica variety, minerals commonly found on Earth,” said Dr. Carl Melis, who led the research as a graduate student at UCLA. “The material orbiting HD 131488 is not one of these dust types. We have yet to identify what species it is – it really appears to be a completely alien type of dust.”

The warm dust in the HD 131488 system is concentrated in an area close to the star, where temperatures are similar to those on Earth. The researchers concluded that the most likely source for dust in that part of the system would be the collision of two rocky planetary bodies. Only five other stars like HD 131488 with dust in their terrestrial planet zone are known. “Interestingly, all five of these stars have ages in the range of 10-30 million years,” Melis said. “This finding indicates that the epoch of final catastrophic mass accretion for terrestrial planets, the likes of which could have resulted in the formation of the Earth-Moon system in our own Solar System, occurs in this narrow age range for stars somewhat more massive than the Sun.”

The team also discovered a unique second dusty region in the outer reaches of the HD 131488 system, comparable to the location of Pluto and other Kuiper Belt objects in our own solar system.
Image Credit: Lynette Cook for Gemini Observatory/AURA

Top: Illustration depicting the location of the warm and cold dust rings in the HD131488 system. Bottom: Comparable regions in our own solar system, with the orbits of the outer planets for scale. Image Credit: Lynette Cook for Gemini Observatory/AURA

“The hot dust almost certainly came from a recent catastrophic collision between two large rocky bodies in HD 131488’s inner planetary system,” Melis said. “The cooler dust, however, is unlikely to have been produced in a catastrophic collision and is probably left over from planet formation that took place farther away from HD 131488.”

“…for some reason stars that have large amounts of orbiting warm dust do not also show evidence for the presence of cold dust. HD 131488 dramatically breaks this pattern,” said Dr. Benjamin Zuckerman, a co-author on the paper and a professor of physics and astronomy at UCLA.

With its unusual dust composition and unique combination of warm and cold dust regions, the HD 131488 system is now under intense scrutiny. Melis and colleagues plan to continue trying to determine the composition of the dust, and will search for other stars with the dusty evidence for planet formation.

Source: Gemini Observatory



Gemini is a constellation of the zodiac, positioned on the ecliptic plane between between Taurus to the west and Cancer to the east. Only its Alpha and Beta stars – Castor and Pollux – are easy to recognize. They represent the “Twins”. Gemini is one of the original 48 constellations charted by Ptolemy and has endured to become a part of the 88 modern constellations recognized by the International Astronomical Union. It covers approximately 54 square degrees of sky and contains 17 main stars in the asterism, with 80 stars possessing Bayer/Flamsteed designations. Gemini is bordered by the constellations of Lynx, Auriga, Taurus, Orion, Monoceros, Canis Minor and Cancer. It can be viewed by all observers located at latitudes between +90° and ?60° and is best seen at culmination during the month of February.

There are two annual meteor showers associated with the constellation of Gemini. The first peaks on or around the date of March 22, and are referred to as the March Geminids. This meteor shower was first discovered in 1973 and then confirmed in 1975. The average fall rate is generally about 40 per hour, but the meteoroid stream is unstudied and it may vary. These appear to be very slow meteors, entering our atmosphere unhurriedly and leaving lasting trails.

The second meteor shower associated with Gemini are the Geminids themselves, which peak on or near the date of December 14th, with activity beginning up to two weeks prior and last several days beyond the date. The Geminids are one of the most hauntingly beautiful and mysterious displays of celestial fireworks all year – first noted in 1862 by Robert P. Greg in England, and B. V. Marsh and Prof. Alex C. Twining of the United States in independent studies. The annual appearance of the Geminid stream was weak initially, producing no more than a few per hour, but it has grown in intensity during the last century and a half. By 1877, astronomers had realized this was a new annual shower – producing about 14 meteors per hour. At the turn of the last century, the rate had increased to over 20; and by the 1930s, up to 70 per hour. Only ten years ago observers recorded an outstanding 110 per hour during a moonless night…

So why are the Geminids such a mystery? Most meteor showers are historic – documented and recorded for hundreds of years – and we know them as originating with cometary debris. But when astronomers began looking for the Geminids’ parent comet, they found none. It wasn’t until October 11, 1983 that Simon Green and John K. Davies, using data from NASA’s Infrared Astronomical Satellite, detected an object (confirmed the next night by Charles Kowal) that matched the orbit of the Geminid meteoroid stream. But this was no comet, it was an asteroid – in fact, a 14th magnitude asteroid which is passing Earth tonight from a distance of less than 18 million kilometers! Now considered a Potential Hazardous Asteroid (PHA), 3200 Phaeton comes within 3.2 million kilometers of Earth’s orbit about every 17 months. Originally designated as 1983 TB, but later renamed 3200 Phaethon, this apparently rocky solar system member has a highly elliptical orbit that places it within 0.15 AU of the Sun during every solar system tour. But asteroids can’t fragment like a comet – or can they? The original hypothesis was that since Phaethon’s orbit passes through the asteroid belt, it may have collided with one or more asteroids, creating rocky debris. This sounded good, but the more we studied the more we realized the meteoroid “path” occurred when Phaethon neared the Sun. So now our asteroid is behaving like a comet, yet it doesn’t develop a tail.

So what exactly is this “thing?” Well, we do know that 5.1 kilometer diameter Phaethon orbits like a comet, yet has the spectral signature of an asteroid. By studying photographs of the meteor showers, scientists have determined that the meteors are denser than cometary material, yet not as dense as asteroid fragments. This leads them to believe Phaethon is probably an extinct comet which has gathered a thick layer of interplanetary dust during its travels, yet retains the ice-like nucleus. Until we are able to take physical samples of this “mystery,” we may never fully understand what Phaethon is, but we can fully appreciate the annual display it produces!

Thanks to the wide path of the stream, folks the world over get an opportunity to enjoy the show of the Geminids. The traditional peak time is the night of the 13th into the morning of the 14th of December – as soon as the constellation of Gemini appears, around mid-evening. The radiant for the shower is near the bright star Castor, but meteors can originate from many points in the sky. From around 2 AM tonight until dawn (when our local sky window is aimed directly into the stream) it is possible to see about one “shooting star” every 30 seconds. The most successful of observing nights are ones where you are comfortable, so be sure to use a reclining chair or pad on the ground while looking up… And dress warmly! Please get away from light sources when possible – it will triple the amount of meteors you see.

In mythology, Gemini is associated with the myth of Castor and Polydeuces. The two brothers Castor and Pollux were twins, of course and no one could tell them apart. According to legend, they joined Jason’s expedition aboard the Argo to the Black Sea in search of the Golden Fleece. When the Argo stopped at the entrance to the King Amycus’ realm, the king challenged them to a boxing match – mainly because no one ever survived. The brothers were known to be fit and ready, so Pollux was the first Argonaut to take on the challenge. As soon as he got a clear shot, Pollux drove his fist into Amycus’ temple, crushing his skull and ended the battle. However, the tale ends rather sadly. Their final adventure took them to lands of Arcadia with two cousins (ex-Argonauts) to raid cattle. When their ill-gotten booty was divided, the cousins took the loot and ran. Of course, Castor and Pollux followed, taking a shortcut to wait. Unfortunately, a cousin discovered Castor first shot him. When Pollux avenged his brother, the other cousin knocked him unconscious with a rock and went in for the kill. Luckily, Zeus was watching and ended the ordeal with a thunderbolt. When Pollux regained consciousness and realized Castor was join, he begged Zeus to remove his immortality. Zeus granted his wish and placed the twins in the sky to remind us of all of brotherly love.

For binocular observers, Gemini has a wealth of treasures. But to find things, you’ve got to know your way around! Let’s start first with Alpha Geminorum – the “a” symbol on our map. This is Castor. Although it might look like just a single star in binoculars, it’s really quite an outstanding triple star system in a telescope. Here you will find two similar magnitude stars separated by just a few seconds of arc – and both of these stars are binary stars, too! The faint, distant orange star, Castor C, is also double star, consisting of nearly identical, low-mass M stars – red dwarfs – and either one, or both of these are flare stars. Pretty remarkable, huh?

Now, go look at brighter Beta Geminorum, the “B” symbol on our map. Pollux is the 17th brightest star in the sky, and this orange giant star is unusual, too. Here we have an X-ray emitter. Pollux has a hot, outer, magnetically supported corona perhaps similar to that surrounding our Sun. But that’s not all. Beta Geminorum has an orbiting planet! That’s right. A planet that’s nearly 3 times the size of Jupiter and orbits its sun about the same distance as Mars orbits ours. So, if we were there, how big would orange giant Pollux look in the sky? Try almost 6 times larger, and belting out 16 times more radiation. Sunblock 6000 anyone?

Our next target is Delta Geminorum – the “8” shape on our map. Delta goes by the traditional name of Wasat, which means middle. Thankfully, that’s right about where it’s positioned! Wasat is positioned very close to the ecliptic plane, so it is an important star to remember since it often gets occulted by the Moon. But that’s not all. Wasat is also a terrific double star, too. Take out the telescope and have a look at this soft white star with the disparate orange companion. It’s a tasty treat!

Now head further down the line for Gamma Geminorum – the “Y” shape on our map. It’s name is Almeisan and it is about 150 light years away from Earth. A binary star? You bet. The major star is a spectroscopic binary, but look for a faint optical companion, too. Hop across the constellation to Theta Geminorum, the “n” shape. Often called Nageba, this 200 light year distant Class A3 star is also a binary that can be split with a telescope. Look for components of magnitudes 3.60 and 5.18, separated by 2.9 arcseconds.

Last on our list of stars is Epsilon Geminorum, the backward “3”. It’s name is Mebsuta and it is about 900 light years away from our solar system. Mebsuta is a supergiant star of spectral class G5, and compared to our Sun, it’s 150 times larger. Like Delta on the other side of Gemini, Epsilon is also very near the ecliptic plane and can also be occulted by the Moon or planets. Be sure to also keep an eye on Zeta Geminorum, too! It is a cepheid variable star, with very nice magnitude changes from 3.62 to 4.18 every 10.15 days. Quite worth following!

Before you put away your binoculars, travel back to Theta and make the starhop to magnificent Messier 35. Also listed as NGC 2168, the awesome open star cluster was discovered by Philippe Loys de Chéseaux in 1745 and independently discovered by John Bevis before 1750. Progressively larger optics will reveal more and more stars… several hundred stars in an area about the size of the full moon. Perhaps 100 million years old, this collection of stellar gems contains several yellow and orange giant stars to delight the eye – but large telescopes will see something else. Located about 15 arc minutes southwest of M35 is another galactic cluster – NGC 2158. At low magnification, it will appear almost like a faint globular cluster – and with good reason. NGC 2158 is over 10 times older and over five times more remote than M35! About 50 arc minutes west from M35, faint, loose open cluster IC 2157 can also be found. For those with ultra-wide field eyepieces, you can often showcase all three objects in the same field of view!

For the telescope, there’s no place like NGC 2392 (RA 7:29; Dec 20:55) about 4 degrees east/southeast of Wasat. Better known as the “Eskimo Nebula”, this planetary nebula has a bright central region and the surrounding dim ring structure. Be sure to up the magnification in even a small telescope on this one. This stellar relic was first spied by William Herschel in 1787 and is a bubble of material being blown into space by the central star’s intense “wind” of high-speed material. Try adding a nebula filter to bring out different and subtle details!

Head now for NGC 2266 (RA 06 43.2 Dec +26 58). This open cluster is probably a billion years old – nearly all of its members evolved to the red giant star phase. From its position high above the galactic plane, low metallicity NGC 2266 has escaped the mixing of dusts and gases contained in the rest of the Milky Way and become the perfect laboratory for studying stellar evolution. Look for a relatively well compressed area of looping faint stars with a combined magnitude of near 10.

Care to try NGC 2420? You’ll find it located at RA 07 38.5 Dec +21 34. This near 8th magnitude galactic star cluster is rich in solar type stars – another scientific playground for learning about the origins and evolution of the Milky Way. With nearly 1000 stars packed densely together in a small region, NGC 2420 originally belonged to another small galaxy that was cannibalized by our own. With an estimated age of 1.7 billion years old, it remains a curiosity because it is moving rapidly through space – and because it hasn’t been tidally pulled apart by our galactic disc. Enjoy this unique view!

There are other star clusters to enjoy in the constellation of Gemini as well, so get a good star chart and enjoy your time with the “Twins”!

Sources: SEDS, Chandra Observatory
Charts Courtesy of Your Sky.