Rockets, Space transport roundup

Space transport roundup – June.2.2020

A sampling of recent articles, videos, and images dealing with space transport (find previous roundups here):

** A SpaceX Falcon 9 successfully placed a Dragon into orbit on Saturday with astronauts Doug Hurley and Robert Behnken on board.  About 19 hours later, the spacecraft successfully docked to the Int. Space Station. This was the first time that a commercial, privately developed launch system put humans into orbit.

As on the first launch attempt last Wednesday,  weather had been poor on Saturday but cleared up in the last hour before the scheduled liftoff time and the launch went very smoothly. The first stage booster landed safely as well on a platform at sea. During a live broadcast from the Dragon (see video below), the astronauts announced that the Dragon had been christened Endeavor.

On Sunday morning the Dragon reached the Station and docked with it about 20 minutes earlier than expected. An hour or so later, the crew opened the hatch and entered the station to hugs from the three station occupants – NASA astronaut Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner.

See also:

More about DM-2 and other SpaceX activities below.

** Virgin Orbit‘s first launch attempt of the LauncherOne rocket failed when the engine cut off shortly after firing. Virgin Orbit Ignites LauncherOne Rocket During First Launch Demo, Mission Safely Terminated – Virgin Orbit

Virgin Orbit, the California-based satellite launch company, conducted a launch demonstration of its innovative air-launched rocket today in the skies over the Pacific Ocean just off the California coast. The company successfully completed all of its pre-launch procedures, the captive carry flight out to the drop site, clean telemetry lock from multiple dishes, a smooth pass through the racetrack, terminal count, and a clean release. After being released from the carrier aircraft, the LauncherOne rocket successfully lighted its booster engine on cue — the first time the company had attempted an in-air ignition. An anomaly then occurred early in first stage flight, and the mission safely terminated. The carrier aircraft Cosmic Girl and all of its crew landed safely at Mojave Air and Space Port, concluding the mission.

“Our team performed their prelaunch and flight operations with incredible skill today. Test flights are instrumented to yield data and we now have a treasure trove of that. We accomplished many of the goals we set for ourselves, though not as many as we would have liked,” said Virgin Orbit CEO Dan Hart. “Nevertheless, we took a big step forward today.  Our engineers are already poring through the data. Our next rocket is waiting. We will learn, adjust, and begin preparing for our next test, which is coming up soon.”

The company’s next rocket is in final stages of integration at its Long Beach manufacturing facility, with a half-dozen other rockets for subsequent missions not far behind. Virgin Orbit’s decision to begin production of multiple rockets well in advance of this test flight will enable the team to progress to the next attempt at a significantly faster pace, shortly after making any necessary modifications to the launch system.

More about the launch attempt: Mission Recap: Our First Launch Demo | Virgin Orbit

About 9 seconds after drop, something malfunctioned, causing the booster stage engine to extinguish, which in turn ended the mission. We cannot yet say conclusively what the malfunction was or what caused it, but we feel confident we have sufficient data to determine that as we continue through the rigorous investigation we’ve already begun. With the engine extinguished, the vehicle was no longer able to maintain controlled flight — but the rocket did not explode. It stayed within the predicted downrange corridors of our projections and our Federal Aviation Administration (FAA) launch license as the vehicle fell to the ocean, posing no risk to public safety, no danger our aircrew or aircraft, and no significant environmental impact.

See also:

** The Japanese HTV-9 cargo vessel berthed to the ISS on May 25th following its launch on a H-IIB rocket on May 20th.: Japan’s Resupply Ship Installed on Station’s Harmony Module – Space Station/NASA

** China launched Long March 2D rocket with two satellites on Sunday, May 31st from the Jiuquan Satellite Launch Center in China’s northwest Gansu Province: China sends two satellites into planned orbit – Xinhua

As an optical remote sensing satellite, Gaofen-9 is capable of providing photographs with a resolution of about one meter.

It will be used in land surveys, urban planning, road network design and crop yield estimates, as well as disaster relief. It can also serve projects along the Belt and Road.

The other satellite, HEAD-4, was developed by Beijing-based HEAD Aerospace Technology Co. Ltd. It can carry out on-orbit information collection, including that on ships and aircraft, and the Internet of Things.

See also Long March 2D lofts Gaofen-9 – NASASpaceFlight.com.

** China launched two technology demo satellites on a Long March-11 launch vehicle on Friday, May 29th from the Xichang Satellite Launch Center, Sichuan Province in southwest China.

An enhanced LM-11 is in development: Designers working on new, more powerful Long March 11 rocket – Chinadaily.com.cn.

** Rocket Lab returning to launchpad following stand-down due to the corona virus. The Don’t Stop Me Now mission (pdf) aims to send an Electron into orbit during a window that between June 11 – 24. The Electron

will launch several small satellites, including the ANDESITE (Ad-Hoc Network Demonstration for Extended Satellite-Based Inquiry and Other Team Endeavors) satellite created by electrical and mechanical engineering students and professors at Boston University. The satellite will launch as part of NASA’s CubeSat Launch Initiative (CSLI) and will conduct groundbreaking scientific study into Earth’s magnetic field. Once in space, the ANDESITE satellite will initiate measurements of the magnetosphere with onboard sensors, later releasing eight pico satellites carrying small magnetometer sensors to track electric currents flowing in and out of the atmosphere, a phenomenon also known as space weather. These variations in the electrical activity racing through space can have a big impact on our lives here on Earth, causing interruptions to things like radio communications and electrical systems. The ANDESITE satellite follows on from Rocket Lab’s first ELaNa (Educational Launch of Nanosatellites) launch for NASA, the ELaNa-19 mission, which launched a host of educational satellites to orbit on Electron in December 2018.

The mission also carries three payloads designed, built and operated by the NRO. The mission was procured under the agency’s Rapid Acquisition of a Small Rocket (RASR) contract vehicle. RASR allows the NRO to explore new launch opportunities that provide a streamlined, commercial approach for getting small satellites into space, as well as provide those working in the small satellite community with timely and cost-effective access to space. This mission follows Rocket Lab’s first dedicated mission for the NRO, Birds of a Feather, which was launched on 31 January 2020 NZT from Rocket Lab Launch Complex 1.

The ANDESITE and NRO payloads will be joined on the mission by the M2 Pathfinder satellite, a collaboration between the University of New South Wales (UNSW) Canberra Space and the Australian Government. The M2 Pathfinder will test communications architecture and other technologies that will assist in informing the future space capabilities of Australia. The satellite will demonstrate the ability of an onboard software-based radio to operate and reconfigure while in orbit.

** EXOS Aerospace engine test a success but ends with test stand tank failure: Dramatic Engine Test Dubbed Success Amidst Explosion | EXOS Aerospace

Set upon the Caddo Mills (Texas) Airport Testpad, Exos Aerospace’s new SARGE R2 rocket engine was ready for testing. The efficient eight-man Operations Team of Exos prepared to conduct a 55- second engine run test.

In the briefest moment, as the valves opened and the liquid oxygen mixed with the Ethanol fuel the ambient noise was sucked into a vapor of silence, then blasted by the roar of a clean-burning engine. For 15 seconds, the perfect fiery exhaust gave a glimpse into the thrust that will fly the Exos’ SARGE R2 rocket.

But the impressive display of power was cut short by the failure of the LOX tank on the test stand, resulting in the near-instantaneous release of the liquid oxygen and ignition of the residual Ethanol in the supply lines between the tanks and the engine. This created all the pomp & circumstance expected of such an energetic event. After the level-two Safety event was under control, the Exos team was in good spirits, as they seemed more focused on the new data and slight performance boost of the SARGE engine than with the theatrics that accompanied the test.

A liquid oxygen tank on the mobile test stand failed during an engine test on Mar.27, 2020. Credits: EXOS Aerospace

** Interview with Masten Space CEO: Evadot Podcast #116 – Sean Mahoney CEO of Masten Space Systems – Evadot

We talk about a huge range of subjects, from how he got there, to entrepreneurial strategies and how the current Space industry is preparing us for a future worth looking forward to.

Sean has over 15 years of corporate and technology industry experience, having founded and led a number of technology start-up ventures, and raised multiple rounds of private funding. Sean received his MBA from Emory University’s Goizueta Business School and serves in a leadership capacity for a number of entrepreneurship and environmental non-profit organizations, including serving as Chairman of the Board of the Space Frontier Foundation.

** Briefs:

==================

Check out the
The Lurio Report
for news and analysis of key developments in NewSpace

The latest issue:
Masten Goes Lunar, Rocket Lab, New Space and a Virus
Vol. 15, No. 3, May 2, 2020

Space Frontier Foundation Award for NewSpace Journalism

==================

** SpaceX:

**** SpaceX achieves human orbital spaceflight after a hectic 18 year trek. In an interview with Irene Klotz  recorded before the launch, Elon Musk describes some of the trials and tribulations that he and SpaceX endured during the long struggle to reach the point where a SpaceX rocket will send people to orbit for the first time: Podcast: Interview with SpaceX’s Elon Musk – Aviation Week Network (subscription not required). He also briefly recounted the SpaceX story during the post-launch briefing on Saturday:

**** Misc. DM-2 resources:

**** SpaceX Falcon 9 launch of 60 Starlink satellites set for Wednesday, June 3rd. They aim to

They aim to capture the nosecone fairings as well:

See also SpaceX to ring in Crew Dragon’s success with a Starlink launch and landing – Teslararti

**** Starship

The Starship program, currently centered at Boca Chica Beach in South Texas, continues to exhibit an amazing mixture of assembly-line vehicle construction running at a furious pace with prototype tests that fluctuate between incremental successes and hugely energetic failures.

On May 19th, the third test firing of the SN4 prototype seemed to go well but as the plume dissipated,  small fires could be seen around the base of the vehicle and the launch mount.  Remote controlled water sprays eventually got the flames under control but it was more than a day before anyone approached the vehicle.

Another test fire happened on Thursday May 28th without any subsequent extraneous fires breaking out:

Before that test, there was an announcement from the FAA that SpaceX had been awarded a license to carry out suborbital test launches for the Starship:

While it appeared from this successful test that the SN4 was poised to do a brief hop, Elon Musk had said in the Aviation Week interview (see above) that they would wait to do a flight after the Crew Dragon launch.  This was presumably to prevent any distraction from the most important SpaceX mission since the founding of the company and to avoid any negative vibes that could result from a mishap.  The road closure schedule and FAA NOTAMs hinted, however, that a test flight might be attempted during the week after the Dragon launch.  SpaceX’s first Starship hop on hold for historic Crew Dragon astronaut launch – Teslarati

Pushing its luck, SpaceX tried another engine tests on Friday, May 29th. The Raptor firing  appeared to go well but a minute or so after the engine shut off, methane began pouring out at a point on the interface between the support stand and the vehicle. A few seconds later, a huge fiery explosion enveloped the vehicle when the methane ignited. After the flames and smoke died down, it appeared that the vehicle had vanished but in fact its mangled remains lay on the ground be the test stand. SpaceX Starship SN4 prototype explodes in dramatic fireball – Teslarati.

Elon said in comments following the post-DM2 briefing that the methane leak was due to a problem with a test of the quick disconnect mechanism that allows the fuel line to separate from the vehicle as it lifts off the pad:

Elon Musk, leaving the KSC press site just now, said of yesterday’s Starship test in Boca Chica Texas: “Unfortunately what we thought was going to be a minor test of a quick disconnect ended up being a big problem,” referring to the explosion.

With two out of three engine tests marred by serious problems at the interface between the vehicle and the ground support equipment, it might seem that SpaceX needs to take a pause to do some redesign and component testing. Note that using liquid methane in a large rocket and feeding propellants from the base rather than from umbilical towers are both new technological challenges. It will take SpaceX some time to get them right.

Scott Manley  discusses “What Can We Learn From The Explosion Of The Latest SpaceX Prototype?”:

After several weeks of testing Starship prototype SN4 something went wrong minutes after a successful engine test. A massive fuel leak caused an explosion which wrecked the vehicle and cause significant damage to the test stand. As far as we know nobody was injured and there are prototypes already waiting in the wings to continue tests. …

… I believe that unlike the first few failures due to welding quality this is not related to the manufacture of the rocket, but in the way it’s connected to the ground service equipment that resulted in the propellent loading lines coming loose and spraying liquid methane everywhere.

****** Elon Musk said at the post-launch briefing for DM-2 that he hopes Starship to be operational within 2-4 years, though he admits scheduling is not his strong point. Gwynne Shotwell is on the same page:

****** SpaceX has raised additional funding for development of Starships as well as for the Starlink broadband Internet constellation : SpaceX raises more than half a billion dollars for Starship, Starlink programs – Teslarati

****** Aerial views of the Boca Chica construction and pad sites – Starship SN4 Ultimate Fly Over! – May 25 – LabPadre – YouTube

Feast your eyes on this exquisite aerial footage of SpaceX’s Starship SN4. These images will knock your socks off! SpaceX Boca Chica, Texas is more like a new city now. All images are explicitly owned by LabPadre Media and may not be used without written permission.

****** May.26: SpaceX Ultimate Rocket Shipyard Fly Over! LabPadre – YouTube

Feast your eyes on this exquisite aerial footage of SpaceX’s Starship Shipyard facility. These images will knock your socks off! SpaceX Boca Chica, Texas is more like a new city now. All images are explicitly owned by LabPadre Media and may not be used without written permission.

**** Construction of Prototypes SN5, SN6, and SN7 continues. The videos below show that SN5  is stacked except for a nosecone. SN6 is nearly fully stacked as well. Parts for SN7 have been seen. Here is a diagram showing the state of SN6 assembly:

****** May 23:  SpaceX Boca Chica – Starship SN6 Section in the High Bay – NASASpaceflight – YouTube

While SN4 undergoes work at the launch site, SN5 is waiting in the VAB/High Bay, with a SN6 section paying a visit. Video also includes new – and very cool – SpaceX Food Truck! Video and Photos from Mary (@bocachicagal).

****** May 30:  SpaceX Boca Chica – Starship SN4 Aftermath – Successors Line Up – NASASpaceflight – YouTube

****** May 31: SpaceX Boca Chica – New Starships Prepare during Launch Site clearing – NASASpaceflight – YouTube

Several Starships are waiting for their turn at testing on the Boca Chica launch mount(s) as the clearing of SN4’s remains continues – notably under a Sunday Rainbow. Video and Photos from Mary (@bocachicagal). Edited by Jack Beyer (@thejackbeyer).

****** June 1: SpaceX Boca Chica – Starships SN5 and SN6 in the High Bay – SN7 Sleeved – NASASpaceflight – YouTube

****** June 2: SpaceX Boca Chica – SPadre – YouTube

** Webcast rocket reports:

**** Starship SN4 Explodes, Crew Dragon Demo 2, Rocket Lab’s 3 years and Virgin Orbit LauncherOne test – Marcus House

**** SpaceX Starship Updates – Crew Dragon Demo 2 Launch Attempt Summary – What about it!?

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Activism, Roundup

Space policy roundup – June.2.2020

A sampling of links to recent space policy, politics, and government (US and international) related space news and resource items that I found of interest (find previous space policy roundups here):

International space

Webcasts:

** Episode 18 Safety vs Mitigating Risk – Michael Listner, Space Law & Policy Solutions

** The Space Show – Fri. 05/29/2020 – Professor Madhu Thangavelu “spoke about SpaceX, returning to the Moon, commercial space, the USC back to school opening plans due to Covid 19 and more”.

** Hotel Mars/The Space Show – Wed. 05/27/2020 – John Batchelor and Dr. David Livingston

discussed the SpaceX Demo-2 Crewed Dragon flight planned for the ISS but which was cancelled due to weather issues. I discussed what was shown for the mission on most all TV channels as the global interest in the mission and the launch was significant. During this short one segment 10 minute discussion, you will come away with a brief but accurate description of the SpaceX production for this launch. Those of you familiar with NASA launches, compare and contrast this SpaceX launch to what you saw for Apollo and later the Shuttle

** The Space Show – Tues.05/26/2020 – Dr. Michael Weil talked about “radiation exposure in deep space, cancer, NASA radiation requirements, strategies and more”. (See slides (pdf) discussed during the program.)

**  Webinar Replay | Defending the high ground (and rescuing astronauts) – SpaceNews.com

With the successful launch and docking of NASA and SpaceX’s historic Demo-2 mission, SpaceNews talks with the Space Force brass supporting this and future commercial crew missions. Maj. Gen. John Shaw and Brig. Gen. Doug Schiess join SpaceNews Staff Writer Sandra Erwin and Editor-in-Chief Brian Berger for a broad-based discussion on Space Force operations, including the U.S. military’s role in rescuing astronauts.

Shaw and Schiess were joined by the 45th Operations Group’s Detachment 3 commander, Lt. Col. Michael Thompson, to talk about how the military revived and trained for the astronaut-rescue role it has performed since the Apollo era.

Astronaut rescue is a small but important part of Maj. Gen. Shaw’s duties as the head of the U.S. Space Command’s Combined Force Space Component, which plans and executes day-to-day military space operations and has tactical control of American and multinational space forces during a conflict.

Shaw, as a dual-hatted general, also leads the U.S. Space Force’s Space Operations Command, responsible for organizing, training and equipping the space forces that fly the U.S. military’s satellites, launches its rockets, stands sentinel over the orbital commons, and supports American and allied combat operations.

Shaw also addressed how the ongoing standup of the U.S. Space Force is bringing greater focus to the role space plays in all military operations and what’s at stake in defending the ultimate high ground.

** May 26, 2020 Zimmerman/Batchelor podcast | Behind The Black

** May 29, 2020 Zimmerman/Batchelor podcast | Behind The Black

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Astronomy, Space participation

Night sky highlights for June 2020

[ Update June.12.2020: What’s Up: June 2020 – NASA JPL:

What are some skywatching highlights you can see in June 2020? Look for the Summer Triangle rising in the east after sundown, keep tabs on the morning planets and June 20 brings the solstice. Additional information about topics covered in this episode of What’s Up, along with still images from the video, and the video transcript, are available at https://solarsystem.nasa.gov/whats-up… Credit: NASA-JPL/Caltech

]

** Tonight’s Sky: June – Space Telescope Science Institute

Though the nights are shorter in June, they are filled with fine sights. Look for the Hercules constellation, which will lead you to a globular star cluster with hundreds of thousands of densely packed stars. You can also spot Draco the dragon, which will point you to the Cat’s Eye Nebula. Keep watching for space-based views of globular star clusters and the nebula.

** What’s in the Night Sky June 2020 #WITNS | Solar Eclipse | Milky Way | NLCs – Alyn Wallace

** What to see in the night sky: June 2020 – BBC Sky at Night Magazine

What can you see in the night sky this month? Astronomers Pete Lawrence and Paul Abel reveal their stargazing tips for June 2020.

** The Night Sky June 2020 – Auriga Astronomy – Science made Simple!

A look at the Planets and Major stars/Constellations visible during June 2020 (the shortest nights of the year)

** Skywatch: What’s happening in the heavens in June – The Washington Post

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Activism, Space Policy

The Space Show this week – June.1.2020

The guests and topics of discussion on The Space Show this week:

1. Monday, June 1, 2020; 7 pm PDT (9 pm CDT, 10 pm EDT: No special programming.

2. Tuesday, June 2, 2020; 7 pm PDT (9 pm CDT, 10 pm EDT): We welcome space engineer Dr. Dana Andrews for his new book, Chasing The Dream, which “tells what really happened in our space program over the past 50 years”.

3. Wednesday, June 3, 2020: Hotel Mars TBA pre-recorded. See upcoming show menu on the home page for program details.

4. Thursday, June 4, 2020; 7-8:30 pm PDT (9-10:30 pm CDT, 10-11:30 pm EDT): No special programming.

5. Friday, June 5, 2020; 9:30-11 am PDT (11:30 am-1 pm CDT, 12:30-2 pm EDT): We welcome CEO Jaume Sanpera of Sateliot, a 5G Spanish company that aims to be “the first satellite telecom operator for global continuous IoT connectivity merging satellite and terrestrial networks under 5G protocol“.

6. Sunday, June 7, 2020; 12-1:30 pm PDT (3-4:30 pm EDT, 2-3:30 pm CDT): Welcome to OPEN LINES. All calls welcome, first time callers welcome. Space, STEM, STEAM, science, policy. Join the discussion.

Some recent shows:

** Sun. 05/31/2020 – Dr. Joyce Liao discussed eye-brain microgravity issues.

**  Fri. 05/29/2020 – Professor Madhu Thangavelu “spoke about SpaceX, returning to the Moon, commercial space, the USC back to school opening plans due to Covid 19 and more”.

** Hotel Mars/The Space Show – Wed. 05/27/2020 – John Batchelor and Dr. David Livingston

discussed the SpaceX Demo-2 Crewed Dragon flight planned for the ISS but which was cancelled due to weather issues. I discussed what was shown for the mission on most all TV channels as the global interest in the mission and the launch was significant. During this short one segment 10 minute discussion, you will come away with a brief but accurate description of the SpaceX production for this launch. Those of you familiar with NASA launches, compare and contrast this SpaceX launch to what you saw for Apollo and later the Shuttle

** Tues.05/26/2020 – Dr. Michael Weil talked about “radiation exposure in deep space, cancer, NASA radiation requirements, strategies and more”. (See slides (pdf) discussed during the program.)

** See also:
* The Space Show Archives
* The Space Show Newsletter
* The Space Show Shop

The Space Show is a project of the One Giant Leap Foundation.

The Space Show - David Livingston
The Space Show – David Livingston

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Astronomy

ESO: Small hot stars display giant magnetic spots and super-flares

The latest report from ESO (European Southern Observatory):

Hot stars are plagued by giant magnetic spots, ESO data shows

Astronomers using ESO telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters, called extreme horizontal branch stars. This image shows an artist’s impression of what one of these stars, and its giant whitish spot, might look like. The spot is bright, takes up a quarter of the star’s surface and is caused by magnetic fields. As the star rotates, the spot on its surface comes and goes, causing visible changes in brightness.

Astronomers using European Southern Observatory (ESO) telescopes have discovered giant spots on the surface of extremely hot stars hidden in stellar clusters. Not only are these stars plagued by magnetic spots, some also experience superflare events, explosions of energy several million times more energetic than similar eruptions on the Sun. The findings, published today in Nature Astronomy, help astronomers better understand these puzzling stars and open doors to resolving other elusive mysteries of stellar astronomy.

The team, led by Yazan Momany from the INAF Astronomical Observatory of Padua in Italy, looked at a particular type of star known as extreme horizontal branch stars — objects with about half the mass of the Sun but four to five times hotter.

“These hot and small stars are special because we know they will bypass one of the final phases in the life of a typical star and will die prematurely,” says Momany, who was previously a staff astronomer at ESO’s Paranal Observatory in Chile. “In our Galaxy, these peculiar hot objects are generally associated with the presence of a close companion star.”

Spots on extreme horizontal branch stars (right) appear to be quite different from the dark sunspots on our own Sun (left), but both are caused by magnetic fields. The spots on these hot, extreme stars are brighter and hotter than the surrounding stellar surface, unlike on the Sun where we see spots as dark stains on the solar surface that are cooler than their surroundings. The spots on extreme horizontal branch stars are also significantly larger than sunspots, covering up to a quarter of the star’s surface. While sunspots vary in size, a typical size is around an Earth-size planet, 3000 smaller than a giant spot on an extreme horizontal branch star.

Surprisingly, however, the vast majority of these extreme horizontal branch stars, when observed in tightly packed stellar groups called globular clusters, do not appear to have companions. The team’s long-term monitoring of these stars, made with ESO telescopes, also revealed that there was something more to these mysterious objects. When looking at three different globular clusters, Momany and his colleagues found that many of the extreme horizontal branch stars within them showed regular changes in their brightness over the course of just a few days to several weeks.

“After eliminating all other scenarios, there was only one remaining possibility to explain their observed brightness variations,” concludes Simone Zaggia, a study co-author from the INAF Astronomical Observatory of Padua in Italy and a former ESO Fellow: “these stars must be plagued by spots!”

Spots on extreme horizontal branch stars appear to be quite different from the dark sunspots on our own Sun, but both are caused by magnetic fields. The spots on these hot, extreme stars are brighter and hotter than the surrounding stellar surface, unlike on the Sun where we see spots as dark stains on the solar surface that are cooler than their surroundings. The spots on extreme horizontal branch stars are also significantly larger than sunspots, covering up to a quarter of the star’s surface. These spots are incredibly persistent, lasting for decades, while individual sunspots are temporary, lasting only a few days to months. As the hot stars rotate, the spots on the surface come and go, causing the visible changes in brightness.

Beyond the variations in brightness due to spots, the team also discovered a couple of extreme horizontal branch stars that showed superflares — sudden explosions of energy and another signpost of the presence of a magnetic field.

“They are similar to the flares we see on our own Sun, but ten million times more energetic,” says study co-author Henri Boffin, an astronomer at ESO’s headquarters in Germany. “Such behaviour was certainly not expected and highlights the importance of magnetic fields in explaining the properties of these stars.”

After six decades of trying to understand extreme horizontal branch stars, astronomers now have a more complete picture of them. Moreover, this finding could help explain the origin of strong magnetic fields in many white dwarfs, objects that represent the final stage in the life of Sun-like stars and show similarities to extreme horizontal branch stars.

“The bigger picture though,” says team member, David Jones, a former ESO Fellow now at the Instituto de Astrofísica de Canarias, Spain, “is that changes in brightness of all hot stars — from young Sun-like stars to old extreme horizontal branch stars and long-dead white dwarfs — could all be connected. These objects can thus be understood as collectively suffering from magnetic spots on their surfaces.”

To arrive at this result, the astronomers used several instruments on ESO’s Very Large Telescope (VLT), including VIMOS, FLAMES and FORS2, as well as OmegaCAM attached to the VLT Survey Telescope at Paranal Observatory. They also employed ULTRACAM on the New Technology Telescope at ESO’s La Silla Observatory, also in Chile. The breakthrough came as the team observed the stars in the near-ultraviolet part of the spectrum, allowing them to reveal the hotter, extreme stars standing out bright amongst the cooler stars in globular clusters.

Links

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