AAS News RSS

Editor’s Note: This week we’re at the 228th AAS Meeting in San Diego, CA. Along with a team of authors from astrobites.com, I will be writing updates on selected events at the meeting and posting twice each day. Follow along here or at astrobites.com, or catch our live-tweeted updates from the @astrobites Twitter account. The usual posting schedule for AAS Nova will resume next week.

Come visit Astrobites at the AAS booth ... we have swag!

Come visit astrobites at the AAS booth … we have swag!

Things kicked off last night at our undergraduate reception booth. Thanks to all of you who stopped by — we were delighted to hear from undergrads who already know and love the site, educators who want to use it in their classrooms, and students who had not yet been introduced to astrobites and were excited about a new resource!

For the rest of the meeting we will be stationed at the AAS booth in the exhibit hall (booth #211-213), so drop by if you want to learn more (or pick up swag: we’ve got lots of stickers and sunglasses)!

Monday morning was the official start of the meeting. Here are just a few of the talks and workshops astrobiters attended this morning.

Opening Address (by Susanna Kohler)

AAS President Meg Urry kicked off the meeting this morning at 8am with an overview of some of the great endeavors AAS is supporting. We astrobiters had personal motivation to drag ourselves out of bed that early: during this session, Urry announced the new partnership between AAS and astrobites!

Urry touched on some difficult topics in her welcome, including yesterday’s tragedy in Orlando. She reiterated the AAS’s support for the Committee for Sexual-Orientation and Gender Minorities in Astronomy (SGMA). She also reminded meeting attendees about the importance of keeping conference interactions professional, and pointed to the meeting’s anti-harassment policy.

Partnership Announcement (by Michael Zevin)

This morning, the American Astronomical Society announced the new partnership that it will have with Astrobites! We are beyond excited to embark on this new partnership with the Society, which was the culmination of several years of supportive interaction. This new relationship is described further in the press release just issued by AAS.

First plenary: The Ocean World Enceladus (by Chris Faesi)

Enceladus lineup

Enceladus takes its place in the lineup of potential life-bearing solar system bodies.

In the first plenary session of the AAS 228th meeting, Christopher Glein of the University of Toronto took the audience on an exciting tour of the ocean world Enceladus. This small, icy moon of Saturn had been thought rather unremarkable for most of the 2+ centuries since its discovery in 1789, but the Cassini spacecraft’s extended visit over the last decade has revealed it to be a surprisingly dynamic and unique little world. From Cassini’s 23 flybys, we now know that Enceladus is composed of roughly equal parts rock and ice, and, with an albedo of 99%, is the most reflective body in the solar system.

The moon’s surface is not entirely cratered, as are most solar system objects such as our own Moon, but has a southern hemisphere with long fissures that look like tiger stripes on an otherwise smooth surface. Follow-up with the satellite’s highly sensitive instruments revealed that these stripes were heated up to 200 K – much hotter than Enceladus’s typical 75 K surface temperature. There seems to be an energy shortage: the heating expected from Saturn’s tidal influence on the moon is a factor of about ten smaller than what would be required to heat the surface this much. Unraveling this discrepancy is still an area of active study today.

Enceladus also spews powerful jets of salty water and water ice far into space via cryovolcanism, making it the smallest geologically active body in the solar system. Perhaps most intriguingly, this 500 km-diameter moon may be a promising target in the search for extraterrestrial life. The jets are highly alkaline and may contain molecular hydrogen, which links the inorganic and living worlds as a reactant and energy source. Although Cassini’s very fruitful mission will come to a close in 2017 with a death spiral into Saturn, the future is still bright for Enceladus. Glein closed with a preview of the next mission to this special moon: “ELF”, the Enceladus Life Finder, will fly through and analyze Enceladus’s icy plume in unprecedented detail using state-of-the-art instruments and is predicted to fly in 2031.

102: The NASA K2 Mission (by Meredith Rawls)

Everyone’s favorite planet finding telescope continues to impress. In this morning session, we heard highlights about how the repurposed Kepler mission (K2) is contributing to research in areas ranging from nearby brown dwarfs to extragalactic supernovae. The session kicked off with an overview by Knicole Colon, who happily reported extended funding for K2 through 2018, when its fuel is projected to run out.

Bradley Tucker discussed recent extragalactic results from K2, and supernovae in particular. So far, the Kepler Extragalactic Survey has found 17 supernovae and they hope to find at least 20 more in the next three years. Because Kepler observations are so frequent, they reveal previously hidden subtleties in how supernovae fade over time.

Of course, exoplanet science is still a primary goal for the K2 team. Matthew Penny updated us on the status of the in-progress microlensing campaign, which uses Kepler to search for one-off brightening events that indicate the presence of a planet due to gravitational microlensing. Work is also underway by Jeffrey Coughlin and colleagues to improve our ability to automatically detect and confirm exoplanet candidates with the traditional transit technique. They have developed a robotic technique called DAVE (Discovery And Vetting of K2 Exoplanets), which does an impressive job of eliminating false positive eclipse signals. To complement K2 observations of exoplanet transits, astrobites alumna Courtney Dressing presented a method which incorporates observations from the infrared Spitzer Space Telescope to better refine planet properties such as radius.

One of the challenges of K2 compared to Kepler is noise introduced by the spacecraft’s less precise ability to point. Derek Buzasi implored us to not consider any one pipeline that removes this jitter as necessarily “best,” but rather to try several and recognize that different science goals will need different approaches to data processing.

Jeffrey Van Cleve showed examples of what can be accomplished when K2 data is appropriately processed: just like Kepler, K2 can use asteroseismology to see the ringing oscillations of acoustic waves inside evolved stars.

Finally, several speakers including Buzasi presented their work on stellar astrophysics with K2. In addition to stellar activity and asteroseismology, presenters discussed spots and flares on cool brown dwarfs (John Gizis) and using eclipses together with stellar models to measure distances to star clusters (Keivan Stassun). Not a bad roundup for a broken space telescope!

103: Galaxies Big and Small (by Ben Cook)

This session (one of the first parallel sessions of the conference) included a variety of presentations studying galaxies, primarily using observations but ending with a unique purely analytical study. Stephen McNeil began the session by discussing a survey looking for dwarf galaxies in “voids” — the most empty spaces in the universe. Candidate objects can be looked for using a smart choice of photometric color bands, but more work is ongoing to confirm the locations of (and distances to) the objects with spectroscopy. Aaron Romanowsky gave an overview of the field of Ultra-Diffuse Galaxies, a new class of galaxies only discovered within the last 2 years. Some of these galaxies are as large as the Milky Way and seem to have almost as much dark matter, but they contain 1000x fewer stars.

A high-redshift galaxy which is "gravitationally lensed" by a large cluster is shown to the left. The right image shows how big it would look without the magnification. [Slide by Greg Walsh]

A high-redshift galaxy which is “gravitationally lensed” by a large cluster is shown to the left. The right image shows how big it would look without the magnification. [Slide by Greg Walsh]

Greg Walsh presented a longer “dissertation presentation” on his work observing dusty star-forming galaxies. One of the best tools for this job is using galaxy clusters as gravitational lenses to help magnify very distant galaxies. Tianxing Jiang showed a variety of observations and simulations that suggest that the level star formation in a galaxy may have to do with the amount of gas pressure, and Aaron Barth showed new measurements of the masses of Super Massive Black Holes using radio measurements. Barth argues that the key to getting good (10%) accuracy is having very high spatial-resolution.

Bill Forman discussed how many galaxies have extremely hot, ionized gas surrounding them, and Bruce Rout argued that dark matter may not be necessary to explain the rotation curves of galaxies; a complicated analytical model using general relativity can do the job without any dark matter at all.

Press Conference: Exoplanets and Brown Dwarfs (by Susanna Kohler)

The first press conference of the meeting featured four speakers discussing some of the latest developments in the field of exoplanet and brown dwarfs.

rocky body surface

Artist’s impression of the surface of a massive, planet-like body being devoured by a white dwarf. [A. Hara/C. Melis/W. M. Keck Observatory]

First up was Carl Melis (UC San Diego), who discussed the discovery of a rocky exoplanetary body currently being shredded by a white dwarf. As the white dwarf’s strong gravitational pull tears the body apart, we can observe the material pulled from its surface layers. These observations — made by Keck Observatory and Hubble — indicate that the body might have been Earth-like, with an outer surface of made up of limestone. Here’s the press release.

Next, Avi Shporer (NASA Jet Propulsion Laboratory) spoke about the first transiting brown dwarf found in K2 mission data. Stars like companionship, but the companions are usually other massive stars, or Jupiter-size or smaller planets. Companions with the mass and size of brown dwarfs are uncommon, leading to the term “brown dwarf desert”. The brown dwarf found by K2 marks the 12th transiting brown dwarf we have discovered.

Jerome Orosz (San Diego State University) was up next, presenting the largest and longest-period circumbinary planet yet discovered. This planet is in an orbit with a 3-year period around a two-star binary system (think Tatooine!). This is the longest orbital period of any confirmed transiting exoplanet, and this Jupiter-sized planet, which is in the circumbinary’s habitable zone, is the largest circumbinary planet we’ve observed. Here’s the press release.

Finally, Sean Mills (University of Chicago) spoke about Kepler-108, a giant planet system in which the two exoplanets don’t orbit within the same plane. This is detectable because the transits of these planets occur at different times and have different depths in the light curve each time they orbit. Their misalignment may have been caused by a past collision with another planet, which was kicked out of the system in the process.

The LIGO-VIRGO Forum on Hunting Gravitational Wave Counterparts (by Gourav Khullar)

This parallel session, organized by Peter Shawhan (University of Maryland, advancedLIGO) discussed the first major followup campaign of the GW150914 gravitational wave (GW) discovery event by the physics and astronomy community around the world. It was extremely exciting to hear the speakers talk of the actual process behind the mega-collaborative effort following the first GW event. news_project_07032016b_lgThis paper, published on June 3rd this year, was described by Peter, with a strong emphasis on the timeline following the GW alert in raw LIGO data back in September 2015, along with description of the sky map and raw data given to different facilities and collaborations that LIGO-VIRGO had signed Memorandums of Understanding (MOUs) with for rapid and robust followups. The talk also focussed on resources and tutorials available now to unpack and characterize future alerts data from LIGO-VIRGO. This talk was followed by the description of the all sky survey PAN-STARRS, and its joint efforts with LIGO. It was pointed out that PAN-STARRS had already scanned the sky multiple times, which gave the program an edge in determining transients, i.e. recent features appearing on their new maps but not the old. This extensive survey also allowed better characterization of the transient source, which would be the next step for PAN-STARRS and other similar projects.


Following this was a talk by Andy Howell, of the newly formed Las Cumbres Observatory – A Global Telescope Network (LCOGT), made up of multiple telescopes across the US, Chile, Spain, South Africa, China and Australia. Howell emphasized that a robotic pointed-search facility could be extremely crucial in automated alert triggering of GW events in the future. Their galaxy and transient catalog is one to look out for.

Greetings from the 228th American Astronomical Society meeting in San Diego, California! This week, along with a team of fellow authors from astrobites, I will be writing updates on selected events at the meeting and posting twice each day. You can follow along here or at astrobites.com, or catch our live-tweeted updates from the @astrobites Twitter account. The usual posting schedule for AAS Nova will resume next week.

If you’re at the meeting, come stop by the AAS booth (Booth #211-213) to learn about the newly-announced partnership between AAS and astrobites and pick up some swag. And don’t forget to visit the IOP booth in the Exhibit Hall (Booth #223) to learn more about the new corridors for AAS Journals and to pick up a badge pin to represent your corridor!

corridors

eclipse corona

Editor’s note: This week we’re in Boulder, Colorado at the 47th meeting of the AAS Solar Physics Division (SPD). Follow along to catch some of the latest news from the field of solar physics!

Yesterday’s press conference was titled “Preparing for the 2017 Great American Eclipse.” Four speakers highlighted both outreach and research projects that are planned for the eclipse that will cross the continental United States on August 21st next year.

Eclipse from High Altitude

First up, Angela Des Jardins (Montana Space Grant Consortium) introduced us to the nationwide Eclipse Ballooning Project.

ISS eclipse

An eclipse as seen from the ISS. Being up high gives you a very different perspective on eclipses! [NASA]

The last total solar eclipse in the continental United States was in 1979, and people were told to stay inside and watch from their TVs! For the next total solar eclipse in the US, we want the opposite: for everyone to be outdoors and in the path of totality to watch (with eclipse glasses — let’s be safe)! This eclipse is a fantastic educational opportunity, and a way to reach an enormous audience.

And what better way to experience the eclipse than to be involved? The Eclipse Ballooning Project is involving more than 50 student teams from 30 states to fly high-altitude balloons at 20 locations along the total eclipse path. These balloons will send live videos and images from the edge of space to the NASA website.

Why? Being someplace high up provides an entirely different view for an eclipse! Instead of looking up to watch the Moon slide in front of the Sun, you can look down to watch the Moon’s shadow race across the Earth’s surface at thousands of miles per hour. This unique perspective is rare, and has certainly never been covered live. This will be an awesome addition to other coverage of the eclipse!

At Maximum Totality

The next speaker, Gordon Emslie, described the outreach efforts planned at his institution, Western Kentucky University (WKU). The location where the eclipse totality will last the longest — 2 minutes and 40 seconds — is the small town of Hopkinsville, KY. WKU is located a little over an hour away, and both locations are prepared for a large influx of people on eclipse day!

Partial solar eclipse as viewed by the space-based Solar Dynamics Observatory. [NASA/SDO]

Partial solar eclipse as viewed by the space-based Solar Dynamics Observatory. [NASA/SDO]

WKU is located just off the centerline of eclipse path, which has some advantages: this provides better viewing of some of the chromospheric features of the Sun during the eclipse, like priminences and solar loops. WKU is setting up a variety of educational and public outreach activities at their football stadium and the WKU farm, and they encourage you to come visit for the eclipse!

In addition, they are participating in a nationwide experiment called Citizen CATE, short for the Continental American Telescopic Eclipse. This project will use 60 telescopes spanning the 2500 mile path of totality to record continuous data of the eclipse as it travels across the US. The result will be data of a remarkable 90 minutes of totality, revealing the activity of the solar corona and providing an extended view of the eclipse as has never been seen before.

Science During the Eclipse

Next up was Shadia Habbal (University of Hawaii), who is a co-leader of the AAS 2017 Eclipse Task Force. In addition to her education and outreach efforts associated with the eclipse, however, Habbal is a solar eclipse researcher. She and her collaborators are known as the Solar Wind Sherpas, due to the fact that they hand-carry their science equipment around the world for solar eclipses!

Solar corona during a 2008 eclipse, with color overlay indicating emission from highly ionized iron lines. [Habbal et al. 2010]

Solar corona during a 2008 eclipse, with color overlay indicating emission from highly ionized iron lines. [Habbal et al. 2010]

The primary science done during solar eclipses is the study of the solar corona, the region that extends from the solar surface out to several solar radii. This region is too faint to observe normally, but when the light from the Sun’s disk is blocked out, we can examine it.

Unfortunately, the space telescopes that observe the Sun all have relatively narrow fields of view. But during an eclipse, we can gain the larger context for the corona with ground-based observations, with the Moon conveniently blocking the light from the Sun’s disk! The cover photo is a spectacular example of this.

Observations of the corona during eclipses can provide information on both enormous events, like coronal mass ejections, and faint dynamical features, like plasma instabilities and expanding loops. In addition, we can learn about the plasma properties by examining emission from highly charged ions. The upcoming eclipse should provide a great opportunity to do some coronal science!

A Unique Opportunity

The final press-conference speaker for the meeting was Jay Pasachoff (Williams College and Caltech), a veteran solar eclipse observer who was able to speak to what we could expect if we make it into the path of totality next year.

eclipse path

Path of totality across the continental US for the August 2017 eclipse. [Fred Espenak/NASA GSFC]

Pasachoff pointed out that there are nearly 12 million people located within the band of totality. There are probably another 200 million within a day’s drive! He strongly encouraged anyone able to make it to the path of totality to do so, pointing out that the experience in person is completely unlike the experience of watching a video. The process of watching the world around you go dark, he says, is something that simply isn’t captured when you watch an eclipse on TV.

If you plan to travel for the eclipse, Pasachoff’s recommendation is to aim for the northwest end of the path of totality, rather than the southeast end — surprisingly, weather statistics suggest you have a better chance of not getting clouded out in the northwest.

We now have a year left to educate everyone likely to view the eclipse on when and how to view it safely! Accordingly, Pasachoff concluded the conference by providing a series of links on where to find more information:

eclipses.info
totalsolareclipse.org
GreatAmericanEclipse.com
eclipsophile.com

sunspots

Editor’s note: This week we’re in Boulder, Colorado at the 47th meeting of the AAS Solar Physics Division (SPD). Follow along to catch some of the latest news from the field of solar physics!

Yesterday’s press conference provided an excellent overview of some of the highlights of this week’s SPD meeting. Four speakers provided their views on some of the hottest topics in solar physics at the moment, including “stealth” coronal mass ejections (CMEs), sunspot formation, long-term solar-activity trends, and the largest solar telescope ever built.

Stealth CMEs

CME

Solar and Heliospheric Observatory (SOHO) composite image of a coronal mass ejection. [ESA/NASA/SOHO]

First up, Nathalia Alzate (Aberystwyth University) talked about recent success in solving the mystery of so-called “stealth” CMEs, massive solar storms that don’t exhibit the usual clues to their origin. Most CMEs have low-coronal signatures like flares, filament eruptions, jets, etc. that reveal the origin of the CME at the Sun. But stealth CMEs appear without warning, and seem to have no evidence of low-coronal signatures.

But are these signatures not there? Or could we just be missing them? Alzate and her collaborator Huw Morgan used advanced image processing techniques to search for low-coronal signatures associated with 40 CMEs that have been classified as stealth CMEs. Their techniques enhance the observed structure down to fine spatial scales, and help reveal very faint dynamic events.

Sure enough, these processing techniques consistently revealed low-coronal signatures for every single supposed stealth CME they examined. This suggests that all CMEs exhibit some signatures in the low corona — it’s only a matter of being able to process the images well enough to detect them!

Spectacular Sunspot Simulations

Still image from a simulation studying sunspot formation. Compare to the cover image of sunspot observations! [Feng Chen, Matthias Rempel, & Yuhong Fan]

Still image from a simulation studying sunspot formation. Compare to the cover image of sunspot observations! [Feng Chen, Matthias Rempel, & Yuhong Fan]

Next up, Feng Chen (High Altitude Observatory) described recent computational advances in simulating sunspot formation. He and his collaborators have used high-performance computing to build a model that successfully reproduces many of the key properties of sunspots that are observed.

In particular, these simulations track the motions of the magnetic field starting within the interior of the Sun (8000 km below the surface!). The magnetic field is generated and intensified by convection deep within the solar interior. Bundles of magnetic field then rise through the convection zone, eventually breaking through the solar surface and giving rise to sunspots.

This process of tracking the flow as it travels from the convective layer all the way through the solar surface has resulted in what may be some of the highest fidelity simulations of sunspots thus far. The structures produced in these simulations compares very favorably with actual observations of sunspots — including the asymmetry seen in most sunspots.

Counting Spots on the Sun

Continuing the discussion of sunspots, Leif Svalgaard (Stanford University) next took us on a historical journey from the 1600s through the present. For the last 400 years — starting with Galileo — people have kept records of the number of sunspots visible on the Sun’s disk.

Galileo sunspots

One of Galileo’s drawings of his sunspot observations from 1612. [The Galileo Project]

This turns out to be a very useful practice! Total solar irradiance, a measure used as input into climate models, is reconstructed from sunspot numbers. Therefore, the historical record of sunspots over the last 400 years impacts our estimates of the long-term trends in solar activity.

Based on raw sunspot counts, studies have argued that solar activity has been steadily increasing over time. But could this be a misinterpretation resulting from the fact that our technology — and therefore our ability to detect sunspots — has improved over time? Svalgaard believes so.

By studying and reconstructing 18th century telescopes, he demonstrates that modern-day sunspot counts are able to detect three times as many sunspots as would have been possible with historical technology. When you normalize for this effect, the data shows that there has therefore not been a steady increase long-term in sunspot numbers.

World’s Largest Solar Telescope

The final speaker of the press conference was Joe McMullin (National Solar Observatory), who updated us on the status of the Daniel K. Inouye Solar Telescope (DKIST). This 4-meter telescope will be the world’s largest solar telescope, and the first new solar facility that the US has had in several decades.

The DKIST team and facilities, as of March 2016. [NSO]

The DKIST team and facilities, as of March 2016. [NSO]

The technology involved in this spectacular telescope is impressive. Its thin, enormous mirror is polished to within an error of nearly 1/10,000th of a human hair! Underlying the telescope is the most complex solar adaptive optics systems ever created, with 1600 different actuators controlling the system real-time to within an error of 4 nanometers. In addition, the entire facility is designed to deal with a tremendous heat load (which can severely limit the quality of observations).

DKIST’s construction on Haleakala in Hawaii has been underway since 2012, and is making solid progress. The majority of the structures have now been completed, as have most of the major telescope subsystems. The primary hurdle that remains is to integrate all the of components and make sure that they can perform together — no small feat!

DKIST is expected to begin science operations in 2020, with ~10-20 TB of data being produced each day. This data will be freely and immediately accessible to both researchers and the public.

 

X-ray Sun

Editor’s note: This week we’re in Boulder, Colorado at the 47th meeting of the AAS Solar Physics Division (SPD). Follow along to catch some of the latest news from the field of solar physics!

The 2016 SPD meeting was launched this morning from the University of Colorado Boulder campus. Two of the hot topics at this year’s meeting include celebration of the recent move of the National Solar Observatory’s headquarters to Boulder, and discussion of the future Daniel K. Inouye Solar Telescope (DKIST, formerly the Advanced Technology Solar Telescope, ATST). DKIST, planned for a 2019 completion in Hawaii, is the next big telescope on the horizon for solar physics.

Today’s press conference had an interesting focus: instruments providing new high-energy observations of the Sun. Representatives from four different instruments were here to talk about some of the latest X-ray solar observations.

GRIPS

GRIPS

The GRIPS payload flew at 130,000 ft over Antarctica on a giant balloon in January 2016. [NASA/Albert Shih]

First up, Albert Shih (NASA Goddard) described the Gamma-Ray Imager/Polarimeter for Solar flares, or GRIPS. GRIPS is a balloon-borne instrument designed to detect X-rays and gamma rays emitted during solar flares. Up to tens of a percent of the energy in solar flares is emitted in the form of accelerated particles, but the physics behind this process is not well understood. GRIPS observes where the highest-energy particles are accelerated, in an effort to learn more about the process.

GRIPS was launched on 19 January, 2016 and flew for roughly 12 days — gathering ~1 million seconds of data! The logistics of this instrument’s flight are especially interesting, since it was launched from Antarctica and carried by a balloon at a whopping elevation of 130,000 ft (to get high enough that the atmosphere doesn’t absorb all the photons GRIPS is trying to observe). Though the data from the mission has been retrieved, the bulk of the hardware remains where it landed at the end of January. It must wait for the warmer Antarctic weather in December before a team will be able to reach the instrument and recover it!

Over the 12 days it flew, GRIPS observed 21 small, C-class solar flares. Data analysis is currently underway, and the team hopes that these observations will help improve our understanding of the processes underlying these solar flares.

FOXSI

The FOXSI mission launches on a sounding rocket, taking roughly five minutes of hard X-ray data of the Sun during its flights. [NASA/FOXSI]

FOXSI

Next, Camilo Buitrago-Casas (UC Berkeley) introduced us to the Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket. More than anything, FOXSI is a test of new instrumentation that may be key to future observations of the Sun in hard X-rays.

FOXSI is a focusing telescope — something that is significantly more difficult to do with hard X-rays than it is with optical telescopes. Hard X-rays are difficult to bounce off of mirrors since, due to their high energy, they simply pass through the mirrors! The trick is to capture the X-rays at a grazing angle, sending them through a series of nested mirrors that progressively focus the light. Due to this process and new-technology detectors, FOXSI is able to produce very high-quality, low-noise images of some of the hottest solar sources in fine detail.

FOXSI has now flown twice, with a third flight planned for 2018. Each flight gains about five minutes of data while the sounding rocket is above the Earth’s atmosphere in its parabolic trajectory. While this instrument has already produced a wealth of data about tiny solar flares, the ultimate goal is to get FOXSI’s technology on a space-based observatory, allowing for dedicated and longer observations of solar flares.

NuSTAR

Next, Lindsay Glesener (University of Minnesota) spoke about the Nuclear Spectroscopic Telescope Array (NuSTAR) space telescope, which actually has this opportunity for long solar observations — except that it’s a little busy. NuSTAR was primarily designed to look at faint sources in the distant universe. But a few times a year, it takes a few hours to look closer to home, turning to point at the Sun.

NuSTAR

Artist’s concept of NuSTAR, a high-energy space telescope that occasionally takes a break from observing the distant universe to instead point at the Sun. [NASA]

Due to NuSTAR’s extreme sensitivity, there are obviously some challenges in pointing it directly at a nearby, high-intensity source! Large solar flares would completely swamp the telescope’s detectors, but in quiet conditions, NuSTAR is an excellent tool for detecting faint sources.

As a result, NuSTAR recently detected the smallest, faintest X-ray flare ever imaged at high energies. Tiny flares such as this one are very different from the enormous eruptions we’re used to seeing in solar images; these small flares would go unnoticed by a less sensitive instrument. They’re interesting to study, however, because they might provide the solution to the “coronal heating problem” — the question of how the enormous temperature of the solar corona is sustained. It’s thought that continuous eruption of small solar flares could potentially provide the heating necessary to explain the corona’s temperature.

MinXSS

The last speaker of the press conference was Amir Caspi (Southwest Research Institute), who told us about the Miniature X-ray Solar Spectrometer, or MinXSS. MinXSS is a NASA-funded CubeSat — a small but full-feature satellite roughly the size of a loaf of bread. It was deployed from the International Space Station just two weeks ago (16 May), and saw its first light last night (30 May)!

MinXSS will detect soft X-rays from the Sun, with the goal of gaining a better understanding solar flares, nanoflares, and how these impact the Earth. When solar X-rays are absorbed by the Earth’s upper atmosphere, the atmosphere heats up — with photons of different energies causing heating in different atmospheric layers. Understanding this interaction is important for making predictions about how communications signals traveling through the Earth’s ionosphere might be affected.

MinXSS’s mission is roughly 6-12 months long, with a second mission planned after the conclusion of the current one. The team is looking forward to MinXSS’s entry into science mode in a few days time, and the data that will hopefully follow! You can keep up with the latest news from MinXSS on facebook and twitter.

Bonus

Check out the gif below that shows the deployment of MinXSS (the one in front) and a second CubeSat, CADRE, from the ISS! This compilation of photos was put together by James Mason, MinXSS project manager. The photos were taken from the ISS by astronaut Tim Peake. [NASA]

minxss

Sun and Heliosphere corridor

In the lead-up to next week’s 2016 Solar Physics Division (SPD) meeting, we wanted to introduce you to Leon Golub, our new Lead Editor for the Sun and the Heliosphere corridor.

Leon is a Senior Astrophysicist in the High Energy Division at the Harvard-Smithsonian Center for Astrophysics. He specializes in studies of solar and stellar magnetic activity, and he has built numerous rocket and satellite instruments to study the Sun and its dynamic behavior.

* * * * *

Tell me about your field of research and some of your current projects.

I’ve been working primarily on understanding the dynamics of the solar corona, especially using new types of instrumentation that can provide challenges to our theoretical understanding.

ATM

Image of the Apollo Telescope Mount on Skylab. [NASA]

Why did you choose this field?

Shortly after graduating from MIT in experimental high energy physics I found a position with a group that was preparing to launch an X-ray telescope on Skylab as part of the cluster of solar instruments called the Apollo Telescope Mount. I have stayed with that field and related ones ever since.

What do you consider to be some of the biggest open questions in solar and heliospheric research today?

There are so many major questions that it’s difficult to just settle on a few. The heliosphere is defined by the extent of the influence of the Sun on the interstellar medium. It is an exciting time in that area of study, because we now have the ability to make impressive new observations that allow us to test our understanding of that outer boundary.

Within those limits, the Sun has a major influence on solar system objects via its gravitational pull, its light and heat, and the magnetized plasma and high energy particles that it emits in all directions. We are making major discoveries related to how the Sun has influenced the formation and evolution of the planets, including our own planet.

The source of all this influence is, of course, the Sun itself, and we are working to understand how magnetic fields are generated inside the Sun and how they produce the observed dynamic processes once they emerge from inside.

CME

A coronal mass ejection observed by the LASCO C3 instrument on the Solar and Heliospheric Observatory. [NASA/ESA/SOHO]

What do you anticipate will be some of the most exciting topics presented on at the SPD meeting next week?

We have some new and exciting presentations that I’m looking forward to, related to solar magnetism and solar dynamics, especially flares and mass ejections. There are also some spectacular developments going on in improving the quality of ground-based observations, normally limited by the murkiness of our atmosphere. I expect to see some thrilling new observations from them.

What do you do in your work for ApJ?

I am one of the new Lead Editors, heading the Solar and Heliospheric corridor. This is a new level of editorial work situated between the Editor in Chief and the Scientific Editors (SEs). I am also acting as an SE myself, along with the other Solar and Heliospheric SEs.

What do you think makes for a well-authored paper?

I have long thought that a training in journalism is the best preparation for authoring scientific papers. What is your headline? Can you inform the reader succinctly and clearly?

Is there anything else you’d like to share about the publishing process with potential authors?

I would tell potential authors that our primary goal is to help them publish high quality work, and that the review process is critical to that effort. It takes time, but it makes all the difference.

* * * * *

Look for Leon and several of the Scientific Editors for the corridor at the SPD meeting in Boulder next week! Additionally, Leon can be reached by email should you have any questions about the new Sun and Heliosphere corridor.

AAS Publishing News

In the lead-up to next week’s 15th High Energy Astrophysics Division (HEAD) meeting, we wanted to introduce you to our new Lead Editor for the High Energy Phenomena and Fundamental Physics corridor.

More About Frank

Frank TimmesFrank is a researcher at Arizona State University and a recent awardee of the Simons Fellowship in Theoretical Physics. His research interests span a broad range of topics, including gamma-ray astronomy, stellar evolution and supernovae, and high-performance computing and next-generation internet. Among his current activities is, as he puts it, “the development, care, and nurturing of the MESA (Modules for Experiments in Stellar Astrophysics) project” — a well-known stellar evolution software instrument likely to be familiar to anyone working in the field of stellar astrophysics.

In January 2016, Frank was appointed Lead Editor to the new High Energy Phenomena and Fundamental Physics corridor for AAS journals. What are some of the interesting things he sees on the horizon for these fields? “The integrated whole of new observations from current missions such as NuSTAR and LIGO to near-future missions, coupled with advances in fundamental theory and modeling capabilities with the next generation of computing resources.”

Outlook for the HEAD Meeting

The HEAD meeting, occurring 3-7 April in Naples, Florida, promises to be packed full of the latest science coming from the field. For three and a half days, talks, posters and town halls will highlight research on topics from supernovae to cosmic rays, discussing both theory and observations from space- and ground-based observatories.

When asked what he anticipates some of the most exciting topics will be at this year’s meeting, Frank is enthusiastic: “It’s all exciting! I’m looking forward to the special sessions — especially the time-domain astronomy, gravitational waves, and the three accretion sessions. The poster session is often the most insightful, as that’s usually where the rubber meets the road.”

On Being An Author

Frank has been working with the AAS journals since 2009. In his view, the best publications are those that contain significant new results or theories and reflect sufficiently high scientific standards. “A well-authored manuscript is one that tells its story with conciseness, accuracy, and clarity in its prose.”

In closing, Frank offers three suggestions for potential authors:

  1. Watch this youtube video for advice on how to be a successful author.
  2. Give credit to one’s peers for their contributions.
  3. Turnabout is fair play — be a willing and on-time referee when asked!

Frank will be around at the HEAD meeting next week, or he can be reached by email if you have any questions for him about the new High Energy Phenomena and Fundamental Physics corridor.

AAS Publishing News

Watermarking using the command \watermark{DRAFT, v2}.

Watermarking using the command \watermark{DRAFT, v2}.

Are you an astronomer considering submitting a paper to an AAS journal (i.e., AJ, ApJ, ApJ Letters, or ApJ Supplements)? If so, this post is for you! Read on to find out about the exciting new things you can do with the AAS’s newest LaTeX class file, available for download now.

Why the Update?

AAS publishing has maintained a consistent class file for LaTeX manuscript preparation for the past decade. But academic publishing is changing rapidly in today’s era of electronic journals! Since its journals went fully electronic, the AAS has been continuously adding new publishing capabilities based on the recommendations of the Journals Task Force and the needs and requests of AAS authors. The AAS’s manuscript preparation tools are now being updated accordingly.

What’s New in AASTex 6.0?

There are many exciting new features and capabilities in AASTex 6.0. Here are just a few:

  • Tracking options for author revisions include \added{text}, \deleted{text}, \replaced{old}{new}, and \explain{text}.

    Tracking options for author revisions include \added{text}, \deleted{text}, \replaced{old}{new}, and \explain{text}.

    Based on emulateapj
    Do you use the popular class file emulateapj to prepare your manuscripts? AASTex 6.0 is based on emulateapj, rather than on the older AASTex 5.2 (though 5.2 is still supported). This means that it is easy to produce a double-columned, single-spaced, and astro-ph-ready manuscript. Since two thirds of the AAS journals’ authors use emulateapj, this transition was designed to make manuscript preparation and sharing an easier and more seamless process.

  • Tools for collaborations
    Do you work in a large collaboration? AASTex now includes new tools to make preparing a manuscript within a collaboration easier. Drafts can now be watermarked to differentiate between versions. New markup for large author lists streamlines the display so that readers can access article information immediately, yet they can still access the full author list and affiliations at the end of the paper. And author revision markup allows members of a collaboration to track their edits within a manuscript, for clearer organization of versions and edits.
  • An example figure set, which the reader can download as a .tar.gz high-resolution set or as powerpoint slides.

    An example figure set, which the reader can download as a .tar.gz high-resolution set or as PowerPoint slides.

    Additional figure support
    Do you have a lot of similar figures that you’d like associated with the electronic journal article but don’t all need to be included in the article pdf? New support is now available for figure sets, which allow readers efficient access to the full set of images without slowing down their ability to read your article. In addition, AASTex 6.0 now offers new markup for displaying figures in a grid, providing authors with more control over figure placement.

  • New features for tables
    Do you frequently work with large data tables? You might be especially happy with the changes in table-handling in AASTex 6.0. Now you can automatically number columns, hide columns with a single command, specify math mode automatically for a designated column, control decimal alignment, and even split wide tables into multiple parts.
  • software

    Example use of the new software command.

    Software citation support
    Do you want to cite software and third-party repositories within your articles? With AASTex 6.0, there’s now a \software command that can be used to highlight and link to software that you used in your work. In addition, the ApJ BibTeX style file has been updated to support software citation.

Where Can You Get More Information?

Wishing for still more improvements?

The AAS publishing team would love your input! You can contact them at aastex-help@aas.org with additional suggestions or ideas for the next iteration of AASTex.

Editor’s Note: This is a final post from the 227th AAS Meeting in Kissimmee, FL. This special summary of AAS Hack Day, a meeting of AAS members to collaboratively work on various small projects, was written by Meredith Rawls (@Merrdiff) and was originally posted on astrobites.com.

As the 227th American Astronomical Society meeting drew to a close (see highlights from Day 1, Day 2, Day 3, and Day 4), a group of at least 50 attendees spent “Day 4” working on small projects fondly called hacks. Thanks to sponsorship from LSST and Northrup Grumman, the industrious hackers were well-caffeinated and fed so we could devote time and energy to working in groups on one-day projects.

The Hack Day began at 10am with pitches. Anybody with a project idea was welcome to briefly speak and try to convince others to work with them. Only some ideas panned out, but the enthusiasm was palpable. It’s not every day you get a full room of astronomers and affiliates eager to spend hours working on fun and useful projects to benefit the community.

Here is a rundown of what we accomplished. Pretty impressive for a single day! Many thanks to fellow astrobiter Erika Nesvold (now at Carnegie DTM; @erikanesvold) whose hack was live-documenting all the other hacks. Her tweets as @astrobites appeared with the #hackaas hashtag, and her notes made this recap post infinitely easier to write.

Interested in joining the fun? Sign up for Hack Day at the 2017 January AAS meeting (it’s free with meeting registration), and consider applying for the .Astronomy conference this summer.

  • Towards Optimal Session Scheduling: Adrian Price-Whelan (Columbia), David Hogg (NYU), and Scott Idem (AAS) began writing a program to take all submitted abstracts to a conference like AAS and sort them using keywords to avoid scheduling similar talks in parallel sessions. It’s impossible to make everyone happy, but minimizing conflicts will be a huge first step.
  • Gender in Astronomy Conferences: Jim Davenport (WWU), Ben Nelson (Northwestern), Mehmet Alpsalan (NASA Ames), and Erin Maier (University of Iowa) analyzed data collected during the conference on the gender breakdown of who asks questions after oral presentations. Now in its third year, one new finding from the study is that women don’t ask questions as much as men do, but they tend to ask questions more when the speaker is a woman or the first question-asker is a woman.

  • The Early Reference Project: Many pre-1950 publications lack up-to-date citation information because the text is digitally archived as an image. Brendan Wells (UC Santa Cruz) worked with representatives from ADS and Zooniverse to set up a crowd-sourced platform to identify references in these old papers.
  • Glassdome: Ellie Schwab (CUNY) and colleagues Paige Godfrey, Munazza Alam, and Cam Buzzard began work on a website modeled after glassdoor for safely sharing experiences throughout their astronomy careers. Glassdome will feature career path stories, department reviews, and salaries, all optionally anonymous. The site is hosted by ScienceBetter and is under development.
  • Observing Run Sharing: Sometimes near the end of a long night at the telescope you have observed everything you need but still have time left. Short of choosing randomly or hoping a colleague is online in the middle of the night, there is currently no good solution. To address this, Brooke Simmons (UC San Diego) designed a web app that would allow astronomers to submit their favorite night sky targets. The project is still a work in progress.
  • ArXiv Podcast: Ruth Angus (Oxford) started a podcast featuring astronomers summarizing their new papers submitted to astro-ph in one minute. It’s like audio astrobites! If you’ve recently published a paper, Ruth is seeking contributions of one-minute audio recordings.
  • RadioFree LST: Radio observers don’t care when the Sun is up, but they do care if their astronomical objects of interest are above the horizon. Demitri Muna (Ohio State) and Amanda Kepley (NRAO) created a calculator which uses local sidereal time (LST) to determine when sources rise and set based on the position of the observatory and the coordinates of the target.

  • Hidden Killer Detective: The Kepler spacecraft has enabled many discoveries related to exoplanets and stars. But now that K2 is observing in the ecliptic plane, it should also find asteroids. Geert Barentsen (NASA Ames), Tom Barclay (NASA Ames), Meg Schwamb (ASIAA), and Brooke Simmons (UC San Diego) created a new crowd-sourced Zooniverse project so anyone can help search for moving objects that may be asteroids.
  • Expanding Astronomy on Tap: This casual science pub night, started in 2013, is now a regular event in seven cities worldwide. Jeff Silverman (UT Austin) created a Launch Manifesto and guide for bringing Astronomy on Tap to your own city. If you’re interested, fill out their survey to get more information.
  • The Arceli Project: Arceli is publishing online astronomy content. A team led by ScienceBetter and Kelle Cruz (CUNY) including Daina Bouquin (Harvard CfA), Aram Zucker-Scharff, Lars Holm Nielsen (CERN), Jonathan Sick (LSST), Chris Erdmann (Harvard CfA), and Meredith Rawls (NMSU) worked on getting each component of Arceli to talk to the others. Eventually, Arceli will accept submissions of informal scholarly content—like blog posts—which will become archived and citable just like traditional papers.
  • Special Dark: Leonidas Moustakas (JPL/Caltech) and Tonima Ananna (Yale) hosted a special session at this year’s AAS meeting all about dark matter. During hack day, they began a repository for information that may help constrain the nature of dark matter. Assuming dark matter is a particle, many different kinds of astronomical observations can help nail down its properties, but they are scattered all over the literature. The goal is to compile these observations in one place so the community can piece together a more complete picture of dark matter. A preliminary table of overlap from different astronomical surveys is available online.

  • BibTeX Updater: Mike Lund (Vanderbilt) wrote a python program that takes a citation database created by Mendeley and updates its BibTeX reference information. This tool will help anyone who uses Mendeley as a citation manager and writes papers in LaTeX with BibTeX. By the end of the day, someone from Mendeley had already gotten in touch with Mike to talk about implementing his fixes!
  • Improved Plotly Colormaps: The open source Java graphing code plotly.js lacks colorblind-friendly color tables, so Timothy Pickering (STScI) added some. The color schemes include the new default “viridis” from matplotlib and are perceptually uniform, meaning they don’t have any significant perceptual “jumps” in color. They are better for displaying data whether you’re colorblind or not. Look for the new colors to be available after he submits a pull request to the main plotly repository.
  • Interfacing with Amazon’s Web Services: Meagan Lang (UIUC), Kyle Conroy (Vanderbilt), and Kaylan Burleigh (UC Berkeley/LBNL) worked on a package to streamline running computing jobs with Amazon’s distributed computing. Right now, you can run parallelized computer programs with Amazon Web Services and pay per CPU-hour, but it’s a hassle to set everything up and ensure you don’t pay for more time than you need. Their new rc-submit solves this.
  • #MarsFilter: Becky Smethurst (Oxford), Meredith Durbin (STScI), and Jana Grcevich (AMNH) developed a filter for digital photos to make them look like they were taken on Mars by Curiosity.

  • Different Kind of Kepler Light Curve: Every so often, the Kepler spacecraft sends us an image of its entire field of view rather than just small regions of pixels near specific stars. Jennifer Cash (South Carolina U), Lucianne Walkowicz (Adler), and Joe Filipazzo (CUNY) worked with these Full-Frame Images to identify all the sources. The next step is to identify all the stars in the image and perform aperture photometry. There are likely new exoplanets, binary stars, and other interesting variable sources hidden in this dataset.
  • Exoplanets in the WorldWide Telescope (WWT): Did someone say exoplanets? WWT, now run by the AAS, is an open source data visualization tool often used by planetariums to virtually fly around the Universe. David Weigal (Samford U) worked to improve WWT by adding exoplanetary systems. This was tricky, but he was able to demo one example of a planet orbiting a Sirius-like star.
  • Career Paths: Peter Yoachim (UW) and Eric Bellm (Caltech) took different approaches to study career paths in astronomy. Peter tracked how publishing records affect hiring outcomes, while Eric mapped the careers of astronomers with prize fellowships. Explore their findings here and here.
Preliminary results from Peter Yoachim's project show a significantly lower fraction of recent astronomy PhD recipients continue to publish regularly. (Figure courtesy of Peter.)

Preliminary results from Peter Yoachim’s project show a significantly lower fraction of recent astronomy PhD recipients continue to publish regularly. Figure courtesy of Peter.

  • Testing Stationarity of Time Series Data: Matthew Graham (Caltech) and Phil Marshall (Slac) wrote some code to determine whether a set of observations taken over a period of time is stationary. This will be useful for surveys like LSST which observe the same source multiple times over many visits. It is important to have a way to quantify if something has changed since the last time we looked at it. Their idea was inspired by a paper about wavelets.
  • FuzzyBlobs: David Nidever (LSST) and Phil Marshall (Slac) worked on a technique to automatically find nearby satellite galaxies to the Milky Way hidden in images from astronomical surveys. The name stems from the fact that satellite galaxies have a low surface brightness and generally appear as faint, fuzzy blobs in images.
  • Fabric Poster Fashion (#makeAAS at #hackAAS): What do you get when you bring a sewing machine to a hack day? Dozens of creative garments and accessories fashioned from research posters printed on fabric! This idea was originated on twitter by Emily Rice (CUNY), Josh Peek (STScI), and Ashley Pagnotta (AMNH), and dozens of astronomers including Rachael Livermore (UT Austin) and Haley Fica (Columbia) participated.

WWT web client

During the 227th American Astronomical Society meeting last week in Kissimmee, the AAS announced the exciting news that it will become the new institutional home of Microsoft’s WorldWide Telescope (WWT) astronomy software.

WWT is a scriptable and interactive way of browsing the multiwavelength sky as it is seen from Earth, and the universe as we would travel within it. WWT can be run either as a desktop app or from within an internet browser. And — of interest to researchers especially — it’s an incredibly useful way to visualize and contextualize astronomical data.

What does WWT’s transition to the AAS as its new host mean? WWT was open-sourced by Microsoft Research last year, and hosting by the AAS will permit broad community involvement — in the form of contribution of both code and guidance — in WWT’s further development.

All of this begs the question: why might YOU want to use WWT? That depends on whether your goal is to use it for research, education, or just for fun.

WWT for Research

If you thought WWT was just for education and outreach, think again! Here are just a few things you can do with WWT to advance your astronomical research1:

1) Put surveys into context, on top of more than 40 different all-sky images, spanning the electromagnetic spectrum.

2) Perform literature searches from the sky.

3) Compare images and catalogs at different wavelengths, on-the-fly in seconds.

4) Show your own online data to the world, in an API that allows users to see it on the sky in their browsers.

5) Communicate to colleagues and learners about the sky using interactive tours of your data and ideas.

An example of WWT used to perform astronomy research is the recently highlighted work on the “bones of the Milky Way”, in which the authors used WWT to overlay multiple data sets and visually identify and then search for infrared dark clouds along the predicted positions of Milky Way spiral arms.

An example of WWT used to communicate research is given in this paper, wherein a link in the caption of a figure takes the reader to WWT, where the figure has been placed into context of the sky, allowing the reader to navigate around and within the figure. The reader can even identify individual objects within the image (by right-clicking) and access the objects’ information in astronomical databases like SIMBAD or NED, or find publications about the object on ADS. Try it out for yourself!

WWT used in a paper

This gif shows how a link from a figure caption takes the reader to WWT to see the figure data in context. [https://www.youtube.com/watch?v=3eiUffqU8QI]

A final example of WWT’s use for communicating research is the video abstract below. If you want instructions on how to make your own video abstract using WWT, you can find them here.

 

WWT for Education

WWT and students

Students using WWT for a Moon phases lab. [http://wwtambassadors.org/science-education-research]

WWT is an incredibly powerful visualization tool that can be used to bring context to lesson topics in K-12 education as well as university classes. It can be used in a lecture setting to talk about an enormous variety of astronomy topics — from Spitzer data sets to phases of the Moon — and in a lab setting to encourage students to explore on their own and ask questions.

Sample, pre-made tours for teaching various topics can be found here.

A few sample lesson plans can be found here.

WWT for Fun

Hopefully you’ve already been convinced by the descriptions of WWT’s capabilities that it’s worth checking out. If you don’t have a specific goal in mind, you can visit WWT to simply browse the universe, examining anything from planets to nebulae, from constellations to the CMB, from supernovae to galaxy clusters. If you want a little more guidance, try one of the guided tours available. If you’re feeling adventurous, try to make your own!

The fact that WWT will be developed and guided by the broader community of astronomers will only increase its capabilities. We at the AAS are excited to provide WWT’s new home, and we look forward to watching its evolution.

You can access WWT in your browser here.

You can download the WWT desktop application here (for Windows).

More information on how to use WWT for education and outreach can be found at the WWT Ambassadors webpage.

1Recommendations from Alyssa Goodman

1 … 17 18 19 20