Update: Possible ‘Nearby’ Gamma Ray Burst Alert Was False Alarm

Color view of M31 (The Andromeda Galaxy), with M32 (a satellite galaxy) shown to the lower left. Credit and copyright: Terry Hancock.

Following the late night news yesterday of a possible gamma ray burst in our next door neighboring galaxy Andromeda, it was an “Oh darn!” moment this morning to find out the big event was likely a false alarm. The false alert — and the ensuing false excitement — was due to an unlikely combination of Swift’s Burst Alert Telescope (BAT) detecting what was a previously known object and a power outage at Goddard Space Flight Center and Swift Data Center, so that the data couldn’t be analyzed by the regular team of astronomers around the world.

Also, according to a blog post by Phil Evans, a post-doctoral research assistant from the University of Leicester and a member of the support team for Swift, the Swift team never actually announced a claim of such an event, and it turns out that the tentative data that triggered this story was overstated.

“Interestingly, the Swift team never claimed it was [a GRB]; indeed, I haven’t seen any professional communication claiming that this was a GRB,” Evans wrote on his blog. “Why it has been reported throughout the web as a GRB is something I can only speculate on, but Swift has been fabulously successful studying GRBs.”

Definitely read Evans’ entire analysis of the event.

A circular posted from the Swift-XRT team” on NASA’s Gamma-ray Coordinates Network (GCN) system at says that the astronomers “do not believe this source to be in outburst”. On the Nature blog, Alexandra Witze spoke with Swift team member Kim Page, also from the University of Leicester, who told Nature “that the source had been initially mistaken for a new outburst, and that its intensity had been overestimated due to measurement error. Instead, she says, it was a relatively common, persistent x-ray source — possibly a globular cluster — that had previously been catalogued.”

Here’s the circular in its entirety:

We have re-analysed the prompt XRT data on Swift trigger 600114 (GCN Circ.
16332), taking advantage of the event data.

The initial count rate given in GCN Circ. 16332 was based on raw data from
the full field of view, without X-ray event detection, and therefore may
have been affected by other sources in M31, as well as background hot
pixels. Analysis of the event data (not fully available at the time of the
initial circular) shows the count rate of the X-ray source identified in
GCN Circ. 16332 to have been 0.065 +/- 0.012 count s^-1, consistent with
the previous observations of this source [see the 1SXPS catalogue (Evans
et al. 2014): http://www.swift.ac.uk/1SXPS/1SXPS%20J004143.1%2B413420].

We therefore do not believe this source to be in outburst. Instead, it was
a serendipitous constant source in the field of view of a BAT subthreshold
trigger.

This circular is an official product of the Swift-XRT team.

The event caused a tweet-storm last night on Twitter (see #GRBM31) and as many have said, the excitement was magnified because of the ability to spread news quickly via social media:

Astronomer Robert Rutledge, who publishes the Astronomer’s Telegram has given a Tweet-by-Tweet analysis of what happened with the false alarm:

Launch Alert! Watch Live As Three People Rocket To Space Today

The Expedition 40/41 crew prior to their launch to the International Space Station. From left, Alexander Gerst (ESA), Maxim Suraev (Roscosmos) and Reid Wiseman (NASA). Credit: NASA/Victor Zelentsov

In a few hours, you’ll be able to watch three crew members of Expedition 40/41 rocket to space — live from Kazakhstan!

At 3:57 p.m. EDT (7:57 p.m. UTC) a rocket carrying a Soyuz spacecraft is expected to lift off from the Baikonur Cosmodrome, carrying Reid Wiseman (NASA), Alexander Gerst (ESA) and Maxim Suraev (Roscosmos). Full schedule details are below.

NASA TV will turn on the cameras at 3 p.m. EDT (7 p.m. UTC) and stay on the crew until after they make it to orbit. If all goes to plan, NASA TV will then resume coverage at 9 p.m. EDT (1 p.m. UTC) for docking to the International Space Station 48 minutes later.

Next comes the hatch opening. NASA will start coverage at 11 p.m. EDT (3 a.m. UTC) for the opening about 25 minutes later. Greeting the arriving crew members will be the other half of the Expedition 40 crew: Steve Swanson (NASA), Alexander Skvortsov (Roscosmos) and Oleg Artemyev (Roscosmos). The incoming crew traditionally participates in a televised chat with their families once they are a little settled in.

Because these are live events, all schedules are subject to change. Make sure to follow the NASA Twitter feed for any adjustments. For example, during the last launch the Soyuz spacecraft failed to make a burn to bring the crew members to the station quickly, making the crew go to a standard backup procedure that brought them to the station about two days later. No one was at risk, NASA said, and the delayed docking happened flawlessly.

By the way, all three crew members are on Twitter: @astro_alex, @astro_reid and @msuraev.

Possible Gamma Ray Burst Detected in Andromeda, Would be Closest Ever Observed

Raw data showing the raw gamma ray light curve from a possible Gamma Ray Burst in M31 on May 27, 2014 obtained by the Swift Burst Alert Telescope. Credit: Goddard Space Flight Center/NASA

Update (5/28/14 9:20 am EDT): This alert may have been a false alarm. Further analysis showed the initial brightness was overestimated by a factor of 300. An official circular from the Swift-XRT team says “therefore do not believe this source to be in outburst. Instead, it was a serendipitous constant source in the field of view of a BAT subthreshold trigger.” Please read our subsequent article here that provides further information and analysis.

Something went boom in the Andromeda Galaxy, our next door neighbor. The Swift Gamma-Ray Burst telescope detected a sudden bright emission of gamma rays. Astronomers aren’t sure yet if it was a Gamma-Ray Burst (GRB) or an Ultraluminous X-Ray (ULX) or even an outburst from a low-mass x-ray binary (LMXB), but whatever it turns out to be, it will be the closest event of this kind that we’ve ever observed.

One of the previous closest GRBs was 2.6 billion light-years away, while Andromeda is a mere 2.5 million light years away from Earth. Even though this would be the closest burst to Earth, there is no danger of our planet getting fried by gamma rays.

According to astronomer (Bad Astronomer!) Phil Plait, a GRB would have to be less than 8,000 light years away cause any problems for us.

Andromeda Galaxy. Credit: NASA
Andromeda Galaxy. Credit: NASA

This event is providing astronomers with a rare opportunity to gain information vital to understanding powerful cosmic explosions like this.

If it is a GRB, it likely came from a collision of neutron stars. If it is a ULX, the blast came from a black hole consuming gas. If the outburst was from a LMXB, a black hole or neutron star annihilated its companion star.
Astronomers should be able to determine the pedigree of this blast within 24-48 hours by watching the way the light fades from the burst.

How this Blast was Detected

The Swift Burst Alert telescope watches the sky for gamma-ray bursts and, within seconds of detecting a burst Swift relays the location of the burst to ground stations, allowing both ground-based and space-based telescopes around the world the opportunity to observe the burst’s afterglow. As soon as it can, Swift will swiftly shift itself to observe the burst with its X-ray and ultraviolet telescopes.

The burst alert came at 21:21 pm Universal time on May 27, 2014; three minutes later, the X-ray telescope aboard Swift was observing a bright X-ray glow.

News of the event quickly spread across the astronomical community and on Twitter, sending astronomers scrambling for their telescopes.

According to astronomer Katie Mack on Twitter, if this is indeed a GRB, this gamma-ray burst looks like a short GRB.

No two GRBs are the same, but they are usually classified as either long or short depending on the burst’s duration. Long bursts are more common and last for between 2 seconds and several minutes; short bursts last less than 2 seconds, meaning the action can all be over in just milliseconds.

As we noted earlier, more should be known about this blast within a day or so and we’ll keep you posted. In the meantime, you can follow the hashtag #GRBM31 on Twitter to see the latest. Katie Mack or Robert Rutledge (Astronomer’s Telegram) have been tweeting pertinent info about the burst.

SpaceX CEO Elon Musk to Unveil Manned Dragon ‘Space Taxi’ on May 29

SpaceX Dragon cargo freighter berthed to the International Space Station during recently concluded SpaceX-3 mission in May 2014. An upgraded, manrated version will carry US astronauts to space in the next two to three years. Credit: NASA

SpaceX Dragon cargo freighter berthed to the International Space Station during recently concluded SpaceX-3 mission in May 2014. An upgraded, manrated version will carry US astronauts to space in the next two to three years. Credit: NASA
Story updated[/caption]

SpaceX CEO, founder and chief designer Elon Musk is set to unveil the manned version of his firms commercial Dragon spaceship later this week, setting in motion an effort that he hopes will soon restore America’s capability to launch US astronauts to low Earth orbit and the International Space Station (ISS) by 2017.

Musk will personally introduce SpaceX’s ‘Space Taxi’ dubbed ‘Dragon V2’ at what amounts to sort of a world premiere event on May 29 at the company’s headquarters in Hawthorne, CA, according to an official announcement this evening (May 27) from SpaceX.

“SpaceX’s new Dragon V2 spacecraft is a next generation spacecraft designed to carry astronauts into space,” according to the SpaceX statement.

The manned Dragon will launch atop the powerful SpaceX Falcon 9 v1.1 rocket from a SpaceX pad on the Florida Space Coast.

Dragon was initially developed as a commercial unmanned resupply freighter to deliver 20,000 kg (44,000 pounds) of supplies and science experiments to the ISS under a $1.6 Billion Commercial Resupply Services (CRS) contract with NASA during a dozen Dragon cargo spacecraft flights through 2016.

Musk is making good on a recent comment he posted to twitter on April 29, with respect to the continuing fallout from the deadly crisis in Ukraine which has resulted in some US economic sanctions imposed against Russia, that now potentially threaten US access to the ISS in a boomerang action from the Russian government:

“Sounds like this might be a good time to unveil the new Dragon Mk 2 spaceship that @SpaceX has been working on with @NASA. No trampoline needed,” Musk tweeted.

“Cover drops on May 29. Actual flight design hardware of crew Dragon, not a mockup,” Musk added.

The ‘Dragon V2’ is an upgraded, man rated version of the unmanned spaceship that can carry a mix of cargo and up to a seven crewmembers to the ISS.

NASA astronauts and industry experts check out the crew accommodations in the Dragon spacecraft under development by SpaceX. The evaluation in Hawthorne, Calif., on Jan. 30, 2012, was part of SpaceX's Commercial Crew Development Round 2 agreement with NASA's Commercial Crew Program. Credit: NASA
NASA astronauts and industry experts check out the crew accommodations in the Dragon spacecraft under development by SpaceX. The evaluation in Hawthorne, Calif., on Jan. 30, 2012, was part of SpaceX’s Commercial Crew Development Round 2 agreement with NASA’s Commercial Crew Program. Credit: NASA

Dragon is among a trio of US private sector manned spaceships being developed with seed money from NASA’s Commercial Crew Program in a public/private partnership to develop a next-generation crew transportation vehicle to ferry astronauts to and from the ISS by 2017 – a capability totally lost following the space shuttle’s forced retirement in 2011.

Since that day, US astronauts have been totally dependent on the Russian Soyuz capsules for ferry rides to orbit and back.

The Boeing CST-100 and Sierra Nevada Dream Chaser ‘space taxis’ are also vying for funding in the next round of contracts to be awarded by NASA around late summer 2014.

All three company’s have been making excellent progress in meeting their NASA mandated milestones in the current contract period known as Commercial Crew Integrated Capability initiative (CCiCAP) under the auspices of NASA’s Commercial Crew Program.

However, US progress getting the space taxis actually built and flying has been repeatedly stifled by the US Congress who have severely cut NASA’s budget request for the Commercial Crew Program by about half each year. Thus forcing NASA to delay the first manned orbital test flights by at least 18 months from 2015 to 2017.

The situation with regard to US dependency on Russian rocketry to reach the ISS has always been awkward.

But it finally took on new found importance and urgency from politicos in Washington, DC, since the ongoing crisis in Ukraine this year exposed US vulnerability in a wide range of space endeavors affecting not just astronaut rides to the ISS but also the launch of the most critical US national security surveillance satellites essential to US defense.

US space vulnerability became obvious to everyone when Russia’s deputy prime minister, Dmitry Rogozin. who is in charge of space and defense industries, said that US sanctions could “boomerang” against the US space program and that perhaps NASA should “deliver their astronauts to the International Space Station using a trampoline.”

A SpaceX Falcon 9 rocket with Dragon cargo capsule bound for the ISS launched from Space Launch Complex 40 at Cape Canaveral, FL.   File photo.  Credit: Ken Kremer/kenkremer.com
A SpaceX Falcon 9 rocket with Dragon cargo capsule bound for the ISS launched from Space Launch Complex 40 at Cape Canaveral, FL. File photo. Credit: Ken Kremer/kenkremer.com

Rogozin also threatened to cut off exports of the Russian made RD-180 rocket engines which power the first stage of the United Launch Alliance (ULA) Atlas V rocket used to launch numerous US National Security spy satellites.

“Moscow is banning Washington from using Russian-made rocket engines, which the US has used to deliver its military satellites into orbit,” Rogozin said at a media briefing held on May 13.

NASA is also a hefty user of the Atlas V for many of the agency’s science and communication satellites like the Curiosity Mars rover, MAVEN Mars orbiter, MMS, Juno Jupiter orbiter and TDRS.

Musk and SpaceX have also filed lawsuits against the US Air Force to legally block the importation of the RD-180 engines by ULA for the Atlas V as a violation of the US economic sanctions.

So overall, US space policy is in a murky and uncertain situation and Musk clearly aims for SpaceX to be a central and significant player in a wide range of US space activities, both manned and unmanned.

Read my earlier articles about the Atlas V controversy, Rogozin’s statements, Musk’s suit and more about the effects of economic sanctions imposed by the US and Western nations in response to Russia’s actions in Ukraine and the annexation of Crimea; here, here, here, here and here.

SpaceX founder and CEO Elon Musk briefs reporters including Universe Today in Cocoa Beach, FL prior to SpaceX Falcon 9 rocket blastoff with SES-8 communications satellite on Dec 3, 2013 from Cape Canaveral, FL. Credit: Ken Kremer/kenkremer.com
SpaceX founder and CEO Elon Musk briefs reporters including Universe Today in Cocoa Beach, FL prior to SpaceX Falcon 9 rocket blastoff with SES-8 communications satellite on Dec 3, 2013 from Cape Canaveral, FL. Credit: Ken Kremer/kenkremer.com

The 3rd operational Dragon cargo resupply mission completed the 30 day SpaceX-3 flight to the ISS with a successful Pacific Ocean splashdown on May 18.

SpaceX will webcast the Dragon unveiling event LIVE on May 29 at 7 p.m. PST for anyone wishing to watch at: www.spacex.com/webcast

Stay tuned here for Ken’s continuing SpaceX, Boeing, Sierra Nevada, Orbital Sciences, commercial space, Orion, Mars rover, MAVEN, MOM and more planetary and human spaceflight news.

Ken Kremer

SpaceX Falcon 9 rocket successfully launched the SES-8 communications satellite on Dec. 3, 2013 from Pad 40 at Cape Canaveral, FL. Credit: Ken Kremer/kenkremer.com
SpaceX Falcon 9 rocket successfully launched the SES-8 communications satellite on Dec. 3, 2013 from Pad 40 at Cape Canaveral, FL. Credit: Ken Kremer/kenkremer.com

More Camelopardalids: Persistent Trains and that Satellite Fuel Dump Cloud

A Camelopardalids meteor captured at Jebel Al Jais mountain on the morning of May 24, 2014. Credit and copyright: Justin Ng.

The first ever Camelopardalids Meteor Shower ended up being more of a drizzle than a shower, said astrophotographer John Chumack. “The new shower had very few meteors per hour, I estimated about 8 to 12 per hour, most were faint, but it did produce a few bright ones, as seen captured by my Meteor Video Camera network at my backyard observatory in Dayton Ohio.”

The above image is by Justin Ng who went to Jebel Al Jais mountain near Dubai to capture the meteor shower.

As our own Bob King reported the morning after — with several images and apt descriptions of the shower — the peak activity seem to occur around 2:00am to 4:00am EST (0700 to 900 UT).

There was a lot of buzz about a weird gigantic persistent train that occurred early on (about 1 am EST) and it ended up being a cameo appearance by the Advanced Land Observation Satellite a new Japanese mapping satellite, and a fuel dump from a booster stage of the satellite’s launch vehicle. Read more about it at Bob’s article, and see some images of it below.

Also, see a great video capture of a persistent train, shot by astrophotographer Gavin Heffernan:

We’ve had some more images come in via email and on our Flickr page

Persistent trains are the vaporized remains of the tiny meteoroid. The dust is blown around by upper level winds in Earth’s atmosphere.

Here’s a great time-lapse of the plume from the fuel dump. Astrophotographer Alan Dyer called it a “strange glow of light that moved across the northern sky… What I thought was an odd curtain of slow-moving, colourless aurora — and I’ve seen those before — has many people who also saw it suspecting it was a glow from a fuel dump from an orbiting satellite.

This short time-lapse of 22 frames covers about 22 minutes starting at 11:59 pm MDT on May 23 Each frame is a 60-second exposure taken at 2 second intervals, played back at one frame per second.

A Camelopardolids Meteor on May 24, 2014. Credit and copyright: Stephen Rahn.
A Camelopardolids Meteor on May 24, 2014. Credit and copyright: Stephen Rahn.
Camelopardalids Meteor zips past the Big Dipper and Mars on May 24, 2014. Credit and copyright: John Chumack.
Camelopardalids Meteor zips past the Big Dipper and Mars on May 24, 2014. Credit and copyright: John Chumack.

Here’s a video compilation put together by John Chumack:

Closeup of one frame of a timelapse session containing what appears to be a meteor from the  Camelopardalids meteor shower. Credit and copyright: DaretheHair on Flickr.
Closeup of one frame of a timelapse session containing what appears to be a meteor from the
Camelopardalids meteor shower. Credit and copyright: DaretheHair on Flickr.
An animated gif of the strange ‘cloud’ plume from a fuel dump from the launch of a new Japanese mapping satellite. Credit and copyright: DaretheHair.

We’ll add more images as they come in!

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Want to Measure the Distance to the Moon Yourself? Now You Can!

The dazzling full moon sets behind the Very Large Telescope in Chile’s Atacama Desert in this photo released June 7, 2010 by the European Southern Observatory. The moon appears larger than normal due to an optical illusion of perspective. Image Credit: Gordon Gillet, ESO.

Astronomy is a discipline pursued at a distance. And yet, actually measuring that last word — distance — can be incredibly tricky, even if we set our sights as nearby as the Moon.

But now astronomers from the University of Antioquia, Colombia, have devised a clever method that allows citizen scientists to measure the Moon’s distance with only their digital camera and smartphone.

“Today a plethora of advanced and accessible technological devices such as smartphones, tablets, digital cameras and precise clocks, is opening a new door to the realm of ‘do-it-yourself-science’ and from there to the possibility of measuring the local Universe by oneself,” writes lead author Jorge Zuluaga in his recently submitted paper.

While ancient astronomers devised clever methods to measure the local Universe, it took nearly two millennia before we finally perfected the distance to the Moon. Now, we can bounce powerful lasers off the mirrors placed on the Lunar surface by the Apollo Astronauts. The amount of time it takes for the laser beam to return to Earth gives an incredibly precise measurement of the Moon’s distance, within a few centimeters.

But this modern technique is “far from the realm and technological capacities of amateur astronomers and nonscientist citizens,” writes Zuluaga. In order to bring the local Universe into the hands of citizen scientists, Zuluaga and colleagues have devised an easy method to measure the distance to the Moon.

The trick is in observing how the apparent size of the Moon changes with time.

As the moon rises its distance to an observer on the surface of the Earth is slightly reduced.  Image Credit: Zuluaga et al.
As the moon rises its distance to an observer on the surface of the Earth is slightly reduced.
Image Credit: Zuluaga et al.

While the Moon might seem larger, and therefore closer, when it’s on the horizon than when it’s in the sky — it’s actually the opposite. The distance from the Moon to any observer on Earth decreases as the Moon rises in the sky. It’s more distant when it’s on the horizon than when it’s at the Zenith. Note: the Moon’s distance to the center of the Earth remains approximately constant throughout the night.

The direct consequence of this is that the angular size of the moon is larger — by as much as 1.7 percent — when it’s at the Zenith than when it’s on the horizon. While this change is far too small for our eyes to detect, most modern personal cameras have now reached the resolution capable of capturing the difference.

So with a good camera, a smart phone and a little trig you can measure the distance to the Moon yourself. Here’s how:

1.) Step outside on a clear night when there’s a full Moon. Set your camera up on a tripod, pointing at the Moon.

2.) With every image of the Moon you’ll need to know the Moon’s approximate elevation. Most smartphones have various apps that allow you to measure the camera’s angle based on the tilt of the phone. By aligning the phone with the camera you can measure the elevation of the Moon accurately.

3.) For every image you’ll need to measure the apparent diameter of the Moon in pixels, seeing an increase as the Moon rises higher in the sky.

4.) Lastly, the Moon’s distance can be measured from only two images (of course the more images the better you beat down any error) using this relatively simple equation:

Screen Shot 2014-05-27 at 11.47.25 AM

where d(t) is the distance from the Moon to your location on Earth, RE is the radius of the Earth, ht(t) is the elevation of the Moon for your second image, α(t)
is the relative apparent size of the Moon, or the apparent size of the Moon in your second image divided by the initial apparent size of the Moon in your first image and ht,0 is the initial elevation of the Moon for your first image.

So with a few pictures and a little math, you can measure the distance to the Moon.

“Our aim here is not to provide an improved measurement of a well-known astronomical quantity, but rather to demonstrate how the public could be engaged in scientific endeavors and how using simple instrumentation and readily available technological devices such as smartphones and digital cameras, any person can measure the local Universe as ancient astronomers did,” writes Zuluaga.

The paper has been submitted to the American Journal of Physics and is available for download here.

Observing Alert – Space Station ‘Marathon’ Starts This Week

Time exposure showing the International Space Station making a bright pass across the northern sky. Credit: Bob King

What’s your favorite satellite? For me it’s the space station. Not only is it the brightest spacecraft in the sky, but it’s regularly visible from so many places. It’s also unique. Most satellites are either spent rocket stages or unmanned science and surveillance probes. The ISS is inhabited by a crew of astronauts. Real people.

Every time I see that bright, moving light I think of the crew floating about the cabin with their microgravity hair, performing experiments and pondering the meaning of it all while gazing out the cupola windows at the rolling blue Earth below. Starting Friday, the station will make up to 5 flybys a night from dusk till dawn. Marathon anyone?

The ISS’s orbit is inclined 51.6 degrees to the equator and passes overhead for anyone living between 51.6 degrees north and 51.6 degrees south latitude. It’s visible well beyond this zone also but never passes through the zenith outside of these limits. Traveling at a little more than 17,000 mph (27,350 kph) the station completes an orbit in 93 minutes.

Diagram showing the Earth in late May when the space station's orbital track is closely aligned with the day-night terminator. The astronauts see the sun 24-hours a day (midnight sun effect) while we on the ground get to watch repeated passes. Credit: Bob King
Diagram showing the Earth in late May when the space station’s orbital track is closely aligned with the day-night terminator. The astronauts see the sun 24-hours a day (midnight sun effect) while we on the ground get to watch repeated passes. Credit: Bob King

Most of the time we get one easy-to-see bright pass preceded or followed by a fainter partial pass. ‘Partials’ occur when the space station glides into Earth’s shadow and disappears from view during an appearance. But in late May-early June each year, the space station’s orbit and Earth’s day-night terminator nearly align. From the astronauts’ viewpoint, the sun never sets, much like seeing the midnight sun from the Arctic Circle. From down on the planet between latitudes 40-55 degrees north, the ISS remains in sunlight during repeated 90 minute-long orbits.

Instead of once or twice a night, we’ll see passes all night long from dusk till dawn starting about May 30. For instance, on May 31 from Minneapolis, Minn., skywatchers will be treated to four flybys at 12:12 a.m, 1:44 a.m., 3:20 a.m. and 11:23 p.m. The best nights are June 4 and 6 with five passes. By the 10th, the space station ‘marathon’ winds down and we return to 2-3 passes a night.


In late May-early June near the summer solstice, the sun doesn’t set on the International Space Station

The ISS always appears in the western sky first and travels east opposite to the movement of the stars. Low altitude flybys are fainter because there’s more lateral distance between you and the station. Even then the it still shines as bright as Vega. But when the ISS flies overhead, it’s only about 250 miles away, as close as it gets. Then it outshines everything in the night sky except Venus and the moon. Absolutely stunning.

The track of the ISS near Vega in Lyra. From right to left, the station is passing from sunlight into Earth's shadow. Its color transitions from white to red. Credit: Bob King
The track of the ISS near Vega in Lyra. From right to left, the station is passing from sunlight into Earth’s shadow. Its color transitions from white to red. Credit: Bob King

Have you ever noticed that satellites, including the ISS, appear to move in a jerky or zigzag fashion if you watch them closely? What you’re really are your own eyes not moving smoothly as you follow the satellite across the starry sky. My favorite passes are those where the space station fades away mid-flyby as it encounters Earth’s shadow. I always keep binoculars handy for these passes so I can watch the ISS turn color from pale yellow (caused by the gold Mylar plastic used in its many solar panels) to orange and red as it experiences one of its many orbital sunsets.

The phenomenon is easy to capture on camera too. Find out when the station will cross into shadow using the maps from Heavens-Above (see below) and point your tripod-mounted camera in that direction. I typically use a 35mm lens wide open to f/2.8 and a 30-second exposure at either ISO 400 – if still twilight – or 800 in a darker sky.

ISS
The multiple solar panels on the ISS give it the shape of the letter ‘H’ when viewed through a telescope. Other modules are visible too but hard to see as clearly.  Credit: NASA

There are many ways to find out when the ISS will pass over your city. My favorite are the listings in Heavens-Above. Login with your city and you’ll see a complete list with links to create maps of the station’s track across the sky. There’s also Spaceweather’s Satellite Flyby tracker. Type in your zip code and hit enter. Couldn’t be easier. You can also have NASA send you an e-mail when the most favorable (highest, brightest) passes occur by adding your e-mail to the Spot the Station site. Be aware though that you won’t be notified of some of the less favorable passes.


Half-minute video of the space station tracked through a telescope

One last pleasure of space station watching is seeing it in a telescope. Notoriously tricky to track when magnified, after minimal research I’ve come up with a method that allows at least a half dozen people to see it up close during a good flyby. One person mans the finderscope, keeping the station in the center of the crosshairs, while one happy observer after another takes their turn for a look through the eyepiece. Sure, it’s a little herky-jerky, but you’d be surprised how much you can see at magnifications as low as 60x. The solar panels really jump out. Observing solo might mean a couple tries positioning the moving target  ahead of where you think it will cross the field of view and then being ready to lock on and follow.

Well, I’m going to prep for the upcoming marathon. See you in spirit on the course!

Space Robot Fixes Itself, Takes Selfie As Funny Livetweet Happens On The Ground

Dextre, the Canadian Space Agency's robotic handyman aboard the International Space Station. Credit: CSA/NASA

In a thrilling demonstration of space robotics, today the Dextre “hand” replaced a malfunctioning camera on the station’s Canadarm2 robotic arm. And the Canadian Space Agency gleefully tweeted every step of the way, throwing in jokes to describe what was happening above our heads on the International Space Station.

“Dextre’s job is to reduce the risk to astronauts by relieving them of routine chores, freeing their time for science,” the Canadian Space Agency tweeted today (May 27) .

“Spacewalks are thrilling, inspiring, but can potentially be dangerous. They also take a lot of resources and time. So Dextre is riding the end of Canadarm2 today instead of an astronaut. And our inner child is still yelling out ‘Weeeee…!’ ”

The complex maneuvers actually took a few days to accomplish, as the robot removed the broken camera last week and stowed it. Today’s work (performed by ground controllers) was focused on putting in the new camera and starting to test it. You can see some of the most memorable tweets of the day below.

The cookie you see in the first tweet is part of a tradition in Canada’s robotic mission control near Montreal, Que., where controllers have this snack on the day when they are doing robotic work in space.

Incidentally, the Canadian Space Agency bet NASA a box of maple cream cookies in February during a gold-medal Olympic hockey game between the two countries, which Canada won.

NASA’s Mars Landing Idea Will Take To The Air In June

No rocket sleds were harmed in the making of this video. (NASA/JPL)

So what does an agency like NASA do after making a daring new type of landing with the Mars Curiosity rover? Try to make it even better for next time.

NASA is readying a new technology for landing on the Red Planet that is supposed to help brake the spacecraft in the atmosphere by inflating a buffer around the heat shield to slow things down. And after testing this so-called “Low-Density Supersonic Decelerator” on a rocket sled in January and April, the team is ready for the next major test: heading aloft.

As early as June 3, NASA will strap a test device below a high-altitude balloon and send it up to 120,000 feet — about the same altitude that Felix Baumgartner jumped from in 2012. The device will then drop from the balloon sideways, spinning like a football, and reach a velocity of four times the speed of sound. Then the LDSD will inflate, if all goes as planned, and NASA will evaluate how well it performs.

The agency hopes to use this technology to land heavier and heavier spacecraft on the Red Planet. If the testing goes as scheduled and the funding is available, NASA plans to use an LDSD on a spacecraft as early as 2018.

You can read more about LDSD at this website.

Why You Shouldn’t ‘Buy Real Estate’ On Neptune’s Moon Triton

Neptune's largest Moon, Triton. Astronomers think that Triton is a captured Kuiper Belt Object. Credit: NASA/JPL

Leaving aside the complications of space treaties, a new video lays out another case for why you wouldn’t want to purchase property on Triton — at least, if you were buying for the ultra-long term, over millions of years. The moon is being slowed down by Neptune and will eventually crash or break up into a ring system.

All joking aside, the video also puts forward an interesting hypothesis: that Triton was once a dwarf planet, with a companion, and that Neptune captured Triton and flung the companion away when the giant gas planet moved further out into the solar system, billions of years ago.

Checking into the theory’s credentials, it’s worth noting that the author — Kurzgesagt — represents a startup company that has posted other videos about the solar system. They’re cutely done, although the company’s website does not appear to list any names, at least yet; they describe themselves as a “team of designers, journalists and musicians.”  (That might be because they’re operating in “stealth mode”, a term describing startups that aren’t quite ready to make their idea or founders public yet.)

The theory Kurzgesagt cites is peer-reviewed, however. A 2006 Nature paper called “Neptune’s capture of its moon Triton in a binary–planet gravitational encounter” describes Triton as being part of a binary system in the past, somewhat similar to Pluto and Charon.

NASA’s web page about Triton doesn’t mention the binary system or dwarf planet hypothesis, but says “scientists think Triton is a Kuiper Belt Object captured by Neptune’s gravity millions of years ago.” (The Kuiper Belt is a collection of objects near Neptune’s orbit.)

Some of the reasons include its strange orbital motion that is opposite to Neptune’ s rotation, and the fact that Triton is overwhelmingly the largest moon in the system — suggesting it ejected other ones when it was captured.

Makes you want to send another spacecraft to Neptune, doesn’t it? The first and only visitor there, Voyager 2, flew past there in 1989.