So much space news, so little time. We had a great Weekly Space Hangout with several of our familiar space journalist friends. No huge stories, but lots of interesting tidbits, about asteroid protection, balloon trips to the edge of space, and the discovery of the furthest galaxy.
Host: Fraser Cain
Panel: Alan Boyle, Amy Shira Teitel, David Dickinson, Nancy Atkinson, Elizabeth Howell
We record the Weekly Space Hangout every Friday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch us live on Google+, Universe Today, or the Universe Today YouTube page.
“If we get hit 20 years from now, that’s not bad luck. That’s stupidity.”
That’s what former NASA astronaut Ed Lu has to say about asteroids and our efforts to search for them. He delivered those comments at a panel discussion today at New York’s American Museum of Natural History. He and several other astronauts spoke on behalf of the Association of Space Explorers (which, as the name implies, consists of astronauts, cosmonauts and the like.)
We guess that as astute readers of our publication, you know that a planetary threat from asteroids (and comets) exists. And there’s certainly more we can do; when that 17-meter asteroid blasted Russia earlier this year, Lu said most space agencies learned about it from social media!
So what’s being done about these threats? Here’s a roundup of the panel discussion’s information and some related information.
Asteroid searching and deflection:
Since Lu is the CEO of the B612 Foundation, there was a heavy emphasis on the agency’s proposed Sentinel telescope. Intended to launch in 2018, it would survey the solar system in infrared and seek out potential hazards.
To date, NASA’s NEO Observations Program has found 95 per cent of near-Earth objects larger than one kilometer, Jet Propulsion Laboratory scientist Amy Mainzer told Universe Today in a separate conversation today.
Mainzer also brought us up to speed on the Near-Earth Object Camera (NEOCam)proposal, which she’s been working on since 2005. Her group received technology development funding in 2010 to improve their infrared detectors, which succeeded in passing recent tests. Their group will seek more funding for NASA in the next opportunity.
TheWISE spacecraft’s NEOWISE mission, meanwhile, is going to restart early next year, Mainzer added. “While NEOWISE is not nearly as capable as NEOCam will be, it will improve our knowledge of the diameters and albedos of about 2,000 NEOs and tens of thousands of main belt asteroids,” Mainzer wrote. “With the NEOWISE prime mission, we discovered more than 34,000 new asteroids and observed >158,000 in total. We have used our data from NEOWISE to set constraints on the number of NEOs and potentially hazardous asteroids.”
Former NASA astronaut Tom Jones shared this slide concerning ideas for asteroid defense. Credit: Tom Jones/Association for Space Explorers/AMNH/Ustream (screenshot)
Getting the United Nations involved:
This week, the United Nations Committee on the Peaceful Uses of Outer Space adopted several steps related to asteroids. It’s planning an International Asteroid Warning Group (to share detections and warn of potential impacts), an Impact Disaster Planning Advisory Group, and a Space Missions Planning and Advisory Group (which would look at deflection missions, options, costs, etc.)
Why go with the United Nations? In the panel, NASA Apollo astronaut Rusty Schweickart explained it this way: deciding how to deflect an asteroid posts risks. You might be moving the impact path past a country that would not have been at risk before the deflection. It’s best to make such moves internationally, rather than having (say) the United States make a decision that could increase Russia’s risk to an asteroid.
The problem? Working by committee is slow, says former Romanian astronaut Dumitru-Dorin Prunariu: “You would think with the United Nations that we started to think about asteroids only in 2007, 8 or 9, but the first input was done by 1999 at the Unispace conference, the United Nations International Conference in Space.” People have been working hard, to be sure, but making a good, inclusive plan just takes time. An action team was formed in 2001, a working group was in place by 2007, and the adoptions by UNCOPUOS (as we stated earlier) took place this week.
Cost of all of this:
Schweickart: “Money is hardly an issue in this. This is a very inexpensive thing to do. It’s organizational setting the actual criteria, thresholds whatever.” It would only cost 1% of the NASA budget for the next 10 years, and less than 0.5% after that. (The NASA budget request for 2014 was $17.7 billion, so 1% of that is $177 million.)
The panel members emphasized that it’s best to start the search early and find the threatening asteroids before things become an emergency. If a moderate-sized asteroid was discovered only a few months out, it might be better just to evacuate the affected area rather than try to pull together a last-minute mission to stop the asteroid.
Astronomers have now discovered one thousand extrasolar planets, reaching a milestone in modern astronomy. (See a recent Universe Today article on the subject.) While many have contributed to this achievement, Dr. Sara Seager of MIT has played a large role over the past two decades by contributing vastly to the field of exoplanet characterization. Her theoretical work led to the first detection of an exoplanet atmosphere.
The following is a condensed interview I held with Seager earlier this week.
What first pulled you in to the field of astronomy?
When I was 10 I got to see a really dark sky (well outside her hometown of Toronto, Canada). I stepped out in the middle of the night and I just saw so many stars. I wish you and everyone could see that. So many stars, I just couldn’t believe it.
You were working at Harvard for your PhD in the mid ‘90s when we first detected exoplanets. What was that like?
The mood was quite different. Today everybody wants to talk about it (exoplanets) and write about it. There’s a lot of hype. But back then it was very quiet.
There was a huge amount of skepticism too. People don’t like change. I want you to imagine a world where the gas giants like Jupiter and Saturn are very far from the star and the terrestrial planets like Earth, Mercury, Venus, and Mars are very close to the star. People had constructed theories on how planetary bodies form based on that one example.
So when the first planets around sun-like stars were found, they were Jupiter-mass planets, but they were several times closer to their star than Mercury is to our Sun. It offended all thoughts, theories, and paradigms … As scientists we’re supposed to be skeptical and push back on new discoveries and theories that are upsetting the system. There was huge skepticism.
How difficult was it during this time to work on exoplanets?
Many people, including my graduate student peers and faculty said, “Why are you doing this (working on exoplanet research)? This is not going to happen. And even if exoplanets are real we’re never going to be able to study their atmospheres,” which is what my PhD was on.
What pushed you through despite all the skepticism?
Ironically, I was not committed to a career in science. I didn’t feel like I needed to be involved with something that was at the 100 percent certainty level. I was free because I didn’t have a plan. I had nothing to lose by doing something I thought was really cool and exciting.
When you’re doing a PhD you’re really learning how to answer a tough question. Usually if you do a homework set in high school, or college, there’s already a known answer. But when you’re doing a PhD, if you’re asking a really hard question that has never been asked before you’re answering that question with your own tools that you’ve developed yourself.
At that time, I knew… the real thing is not just what you’re working on but it’s the tools that you’re using and the things that you’re learning. At the end of the day if you don’t stay in science you have gained a skill that most people don’t have.
What changed then? What kept you in science after graduate school?
I had freedom and really enjoyed what I was doing.
What is your motivation for studying exoplanets? Why should we study exoplanets?
We want to know: Are we alone? We want to know if there is life beyond earth. Eventually we will have dozens to hundreds of potential earth-like planets to study in detail. We want to look at their atmospheres for signs of life by way of biosignature gases.
What do you think is the likelihood that we will discover an earth-like planet orbiting a sun-like star?
Well, it really just depends if we can rally resources and interest in doing this problem. We think we know how to find an earth-like planet around a sun-like star. But it’s a very very very hard endeavor. We think that the earths are out there. It’s just a matter of building the sophisticated space telescopes that we need.
So what are the chances? It’s really more of a political and economical question more than anything else. I think it’s inevitable that eventually we will find one.
Do you have a favorite planet?
I always like to say my favorite planet is the next planet. We have a sort of ADD (attention deficit disorder) in this field where we’re propelled and motivated forward by finding the next exciting planet.
We’ve reached a huge milestone in astronomy of detecting one thousand exoplanets. What does this milestone mean to you?
There’s a caveat here, an uncertainty. We don’t know which one is going to be number one thousand because we don’t agree on the definition of a planet. And even if we did, there’s an uncertainty in the mass and size measurements such that some objects that are called planets probably aren’t planets depending on what definition you want. Occasionally a planet is retracted.
But in general, we’re about to pass the one thousandth mark. What do I think? I think it’s phenomenal. I mean I’m so excited.
The study of exoplanets really started as a field where no one wanted to work on it. People thought it was never going to happen, they thought even if there were real planets we’d never get any measurements beyond stamp collecting – a derogatory phrase we sometimes use in astronomy for science that is not that useful. You just find discoveries and they pile up because you don’t know what to do with them.
We’ve changed the paradigm of planet formation, found exotic types of planets, and we’re right on our way to finding another Earth. So I think it couldn’t be better.
We know that hundreds of thousands of asteroids orbit the Sun, and a very few have a high risk of striking Earth. There are also asteroids that haven’t been discovered yet that can surprise us, as evidenced by the explosion over Chelyabinsk, Russia, last February. This event was confirmation that an asteroid strike is a risk we do face. But also, how do scientists counter the pseudo-scientific claims and fears that asteroids seem to generate? And what opportunities do asteroids provide for mining useful resources?
Watch live today (Friday, October 25, 2013) at 15:00 UTC (11 am EDT) as astrophysicist Neil deGrasse Tyson, astronauts Rusty Schweickart, Tom Jones, Ed Lu, Soichi Noguchi and others discuss the research and the steps that are being taken to avoid these potential natural disasters. With current space technology, scientists know how to deflect the majority of hazardous near-Earth objects, but these technologies have not yet been tested in space, and prevention is only possible if nations work together on detection and deflection.
Here’s the latest attempt to hunt down the water leak that aborted Luca Parmitano’s spacewalk in July: two astronauts aboard the International Space Station removed and replaced a fan pump and water separator inside the spacesuit earlier this week.
All spacewalks with NASA suits are on hold while the agency investigates the leak, and they have been trying mightily. In late July, then on-station NASA astronaut Chris Cassidy demonstrated how the pool of water spread within the helmet (as you can see in these YouTube videos).
This week, on-orbit NASA astronauts Mike Hopkins and Karen Nyberg delved further. While the astronauts are trained before their missions on some suit repairs, this particular type was not something that was covered before they left Earth. After Mission Control walked them through what to do, the astronauts proceeded cautiously as they did the work, NASA said.
“Our engineering teams have identified several different components of the suit, designing a big fault tree, and this is just one of the components that we think could have contributed to the leak in the suit,” said Alex Kanelakos, an extra-vehicular activity flight controller and astronaut instructor, in a new YouTube video.
“Specifically, the water separator is what we’re concentrating our efforts on today.”
As Kanelakos explained, a motor inside the suit drives the fan pump and water separator. The fan circulates oxygen, and the pump pumps the coolant fluid. The water separator, meanwhile, takes out moisture (water) from the ventilation loop and gas that could be trapped inside the water coolant loop. The dried-out air is then returned to the crew member for breathing, and the cycle continues.
In September, Cassidy told Universe Today that the spacesuit is expected to come back to Earth during a future SpaceX Dragon cargo flight. That type of spacecraft is (unusually among space trucks) designed to survive re-entry in the atmosphere, allowing engineers on the ground to examine the spacesuit after it comes back.
Cassidy added that the situation was serious, and he supported NASA’s decision to end the spacewalk (which he was also participating in.) He didn’t think, however, that Parmitano was in immediate danger of drowning. For his part, Parmitano wrote a blog post on the European Space Agency website after his spacewalk, saying that space is an “inhospitable” arena.
As any astronaut is trained to do, Parmitano did consider other contingencies while the leak was happening, he wrote:
“The only idea I can think of is to open the safety valve by my left ear: if I create controlled depressurisation, I should manage to let out some of the water, at least until it freezes through sublimation, which would stop the flow. But making a ‘hole’ in my spacesuit really would be a last resort,” he wrote.
That fix, however, was not implemented as Parmitano and Cassidy made their way back to the station in time for their crewmates to repressurize the hatch and bring their Italian crewmate safely inside.
Undoubtedly, you’ve been seeing the recent images of Comet ISON now that it is approaching its close encounter with the Sun on November 28. ISON is currently visible to space telescopes like the Hubble and amateur astronomers with larger telescopes. But you might be wondering why many images show the comet with a green-ish “teal” or blue-green color.
Amateur Astronomer Chris Schur has put together this great graphic which provides information on the spectra of what elements are present in the comet’s coma.
For the conspiracy theorists out there, the green color is actually a good omen, and lots of comets display this color. The green color is a sign the comet is getting more active as gets closer to the Sun – meaning it is now putting on a good show for astronomers, and if it can continue to hold itself together, it might become one of the brightest comets in the past several years.
“ISON’s green color comes from the gases surrounding its icy nucleus,” says SpaceWeather.com’s Tony Phillips. “Jets spewing from the comet’s core probably contain cyanogen (CN: a poisonous gas found in many comets) and diatomic carbon (C2). Both substances glow green when illuminated by sunlight in the near-vacuum of space.”
Both are normally colorless gases that fluoresce a green color when excited by energetic ultraviolet light in sunlight.
And if those poisonous gasses sound dangerous, don’t worry. They are spread out in space much too thinly to touch us here on Earth. So don’t fall prey to fear mongers who are out to bilk the masses – like people did in 1910 when Comet Halley made a return to the skies and swindlers pitched their ‘gas masks’ and special ‘comet pills’ for protection. And of course, nothing happened.
But back to the color. Chris Schur provided this info along with his graphic:
Your readers may appreciate knowing why comets can appear this color. The background image is the shot I took with my 12.5″ and an ST10xme CCD camera for 20 minutes in mid-October. A pale coloration of the front of the coma is seen. To the lower left is a shot with the same instrument but with a 100 lpmm (line pair per millimeter) diffraction grating in front of the CCD chip to break out the spectra of the objects in the entire field.
Here ISON is faintly seen to the left of center, and the first order spectra a band to its right. But the real answer comes when we use the software called Rspec to analyze this band of light. The result is on the lower right. Normally reflected sunlight is rather flat and bland, and mostly that is what ISON is right now, reflected from dust. But labeled are two humps in the blue and green parts of the spectrum labeled “C2” for a carbon molecule. This blue/green emission pair is what gives ISON the color.
Chris notes that as the comet nears the Sun, astronomers and astrophotographers will be able to resolve more spectral details in the comet. “It will be exciting to watch the changes as more molecules pop out,” Chris said via email, “and possibly when it is closest to the Sun, we just may see some metal lines like iron or magnesium from MELTED vaporized rock. How exciting!”
And for those who insist there is something nefarious about Comet ISON, take a look at this FAQ from our friend Stuart Atkinson, who hosts the great site Waiting for ISON. He addresses the many conspiracy theories that are out there regarding this comet.
How’s that for a beacon? NASA’s Chandra X-ray Observatory has tracked down evidence of at least a couple of past luminous outbursts near the Milky Way’s huge black hole. These flare-ups took place sometime in the past few hundred years, which is very recently in astronomical terms.
“The echoes from Sagittarius A were likely produced when large clumps of material, possibly from a disrupted star or planet, fell into the black hole,” the Chandra website stated.
“Some of the X-rays produced by these episodes then bounced off gas clouds about 30 to 100 light years away from the black hole, similar to how the sound from a person’s voice can bounce off canyon walls. Just as echoes of sound reverberate long after the original noise was created, so too do light echoes in space replay the original event.”
The astronomers saw evidence of “rapid variations” in how X-rays are emitted from gas clouds circling the hole, revealing clues that the area likely got a million times brighter at times.
Watch out, asteroid 1999 JU3: you’re being targeted. As severalmediareports reminded us, the Japan Aerospace Exploration Agency (JAXA)’s Hayabusa-2 asteroid exploration mission will carry a ‘space cannon’ on board — media-speak for the “collision device” that will create an artificial crater on the asteroid’s surface.
“An artificial crater that can be created by the device is expected to be a small one with a few meters in diameter, but still, by acquiring samples from the surface that is exposed by a collision, we can get fresh samples that are less weathered by the space environment or heat,” JAXA states on its website.
Reports indicate JAXA is on schedule to, er, shoot this thing into space for a 2018 rendezvous with an asteroid. The spacecraft will stick around the asteroid for about a year before heading back to Earth in 2020. The overall aim is to learn more about the origin of the solar system by looking at a C-type asteroid, considered to be a “primordial body” that gives us clues as to the early solar system’s makeup.
This beautiful new view of Comet ISON comes from a collaborative effort between astrophotographers Cliff Spohn in Ohio and Terry Hancock in Michigan, taken on October 21, 2013. “The first time in almost two weeks that we have had a break in the clouds and rain we could not miss this rare opportunity to capture ISON using Cliff’s equipment,” said Terry via email. “Credit goes to Cliff for capturing the object while I did the calibration, stacking in CCDStack post processing in CS5 and video editing.”
You can see a timelapse video below, covering 93 minutes of imaging, again on October 21. It’s obvious ISON is still intact and it continues to bright, as it is currently about magnitude 9.
More recent images:
Update: This new one is just in from astrophotographer Damian Peach, and its a beauty! Taken on October 24.
From John Chumack: “I just had to try just a telephoto on Comet ISON while it was near Mars,” John said via email. This view shows Comet ISON (C/2012 S1) near Mars and Regulus, the brightest star in the constellation Leo. This image was taken on October 18, 2013 from
Warrenton, Virginia at 6:27am EST looking over Washington D.C.
This nice image comes from Chris Schur from Arizona, taken on October 14, and is also of the conjunction. “As you may recall, on this date of 10/14 the three objects were in a perfect line going from south to north in Leo,” Chris said via email. “What a spectacular sight in the 11 x 80 binoculars! While the comet was quite faint, a short 1/4 degree of tail could be seen, and the gorgeous blue and orange colors of the planets.”
Chris used a Canon Xti, ASA800 with 10 minutes total integration time, with a 80mm f/4.8 Ziess APO refractor on a Televue GEM. Taken from Payson, Arizona at 5,100 feet elevation.
Here’s your amazing oh-my-gosh-space-is-so-cool video of the day — a “canyon of fire” forming on the Sun after the liftoff and detachment of an enormous filament on September 29-30. A new video, created from images captured by the Solar Dynamics Observatory (SDO) and assembled by NASA’s Goddard Space Flight Center, shows the entire dramatic event unfolding in all its mesmerizing magnetic glory.
Watch it below:
Solarrific! (And I highly suggest full-screening it in HD.) That filament was 200,000 miles long, and the rift that formed afterwards was well over a dozen Earths wide!
Captured in various wavelengths of light by SDO’s Atmospheric Imaging Assembly (AIA) the video shows the solar schism in different layers of the Sun’s corona, which varies greatly in temperature at different altitudes.
According to the description from Karen Fox at GSFC:
“The red images shown in the movie help highlight plasma at temperatures of 90,000° F and are good for observing filaments as they form and erupt. The yellow images, showing temperatures at 1,000,000° F, are useful for observing material coursing along the sun’s magnetic field lines, seen in the movie as an arcade of loops across the area of the eruption. The browner images at the beginning of the movie show material at temperatures of 1,800,000° F, and it is here where the canyon of fire imagery is most obvious.”
Now, there’s not really any “fire” on the Sun — that’s just an illustrative term. What we’re actually seeing here is plasma contained by powerful magnetic fields that constantly twist and churn across the Sun’s surface and well up from its interior. The Sun is boiling with magnetic fields, and when particularly large ones erupt from deep below its surface we get the features we see as sunspots, filaments, and prominences.
When those fields break, the plasma they contained gets blasted out into space as coronal mass ejections… and this is what typically happens when one hits Earth. (But it could be much worse.)