Connect with us

Science

Interstellar Comet 2I/Borisov Formed in a Very Cold Environment – Universe Today

Published

on


In the summer of 2019, a team of astronomers from NASA, the ESA, and the International Scientific Optical Network (ISON) announced the detection of the comet 2I/Borisov. This comet was the only second interstellar visitor observed passed through our Solar System, coming on the heels of the mysterious ‘Oumuamua. For this reason, astronomers from all over the world watched this comet intently as it made its closest pass to the Sun.

One such group, led by Martin Cordiner and Stefanie Milam of NASA’s Goddard Space Flight Center, observed 2I/Borisov using the ESO’s Atacama Large Millimeter/submillimeter Array (ALMA) in the Chilean Andes. This allowed them to observe the gases 2I/Borisov released as it moved closer to our Sun, thus providing the first-ever chemical composition readings of an interstellar object.

Astronomers are naturally interested in the study of comets because they are essentially material left over from the formation of the Solar System. In addition, they spend most of their lives at large distances from any star and in very cold environments. The majority of comets observed in the Solar System, for example, originated in the Kuiper Belt or the Oort Cloud, depending on whether they are short-period or long-period comets.

[embedded content]

In addition, the interior composition of comets has not changed significantly since the formation of the Solar System. Therefore, the study of their interiors can tell scientists a great deal about the processes that occurred during their birth in protoplanetary disks. This becomes possible as comets draw closer to their suns and their ices begin to sublimate (a process known as “outgassing.”)

Interstellar comets are of particular interest to astronomers because they can tell us a great deal about the formation and evolution of star systems other than our own. When they observed 2I/Borisov, the team detected two types of gas molecules being ejected from the comet: hydrogen cyanide (CHN) and carbon monoxide (CO). The study that describes these findings recently appeared in the journal Nature.

While the team expected to see the former, which is present in 2I/Borisov in similar concentrations to what has been observed in Solar System comets, they were surprised to see large amounts of CO as well. In fact, the CO concentrations were estimated to be 9 to 26 times higher than the average Solar System comet or any comet detected within 2 AU of the Sun (twice the distance between the Earth and the Sun.)

“The comet must have formed from material very rich in CO ice, which is only present at the lowest temperatures found in space, below -420 degrees Fahrenheit (-250 degrees Celsius),” said planetary scientist Stefanie Milam in a recent NRAO press release.

ALMA images showing hydrogen cyanide (HCN) and Carbon monoxide (CO) gas being released from 2I/Borisov. Credit: ALMA (ESO/NAOJ/NRAO), M. Cordiner & S. Milam; NRAO/AUI/NSF, S. Dagnello

While CO is one of the most plentiful molecules in space and is found inside most comets, there are typically huge variation in terms of its concentration in comets – for reasons which remain unknown. This may be a result of where they formed in the Solar System and/or how often a comet gets closer to the Sun and loses some of its more-easily evaporated ices. As astrochemist Martin Cordiner explained:

“This is the first time we’ve ever looked inside a comet from outside our solar system, and it is dramatically different from most other comets we’ve seen before… If the gases we observed reflect the composition of 2I/Borisov’s birthplace, then it shows that it may have formed in a different way than our own solar system comets, in an extremely cold, outer region of a distant planetary system.”

In all previous cases where ALMA was used to study protoplanetary disks, those disks were found around Sun-like stars. At the same time, many disks extended far beyond where comets in the Solar System are believed to have formed and contained large amounts of extremely cold gas and dust. While the team can only speculate at this point, they believe it is possible that 2I/Borisov came from one of these larger disks.

Given the speed with which it traveled through our Solar System (33 km/s; 21 mps), astronomers suspect that 2I/Borisov was likely to have been kicked out of its host system by gravitational interaction – possibly from a passing star or a giant planet. After that, it is thought to have spent millions or billions of years travelling through the extreme cold of interstellar space before arriving in our Solar System.

Labeled version of four of the twenty disks that comprise ALMA’s highest resolution survey of nearby protoplanetary disks. Credit: ALMA (ESO/NAOJ/NRAO) S. Andrews et al.; NRAO/AUI/NSF, S. Dagnello

2I/Borisov was discovered on August 30th, 2019 by amateur astronomer Gennady Borisov, who it was named in honor of. The only other insteallr object observed – 1I/’Oumuamua – was already on its way out of the Solar System when it was first detected, which made it very difficult to study the object and determine if it was an asteroid, a comet, a fragment of a comet, or something else entirely (like an alien spacecraft or derelict).

In 2I/Borisov’s case, the presence of an active gas and dust coma surrounding it confirmed that it was the first known interstellar comet to ever be observed. The fact that it’s composition is unlike that of comets observed in the Solar System only makes it more appealing for researchers, and is an invitation to find more interstellar comets. As Milam put it:

“2I/Borisov gave us the first glimpse into the chemistry that shaped another planetary system. But only when we can compare the object to other interstellar comets, will we learn whether 2I/Borisov is a special case, or if every interstellar object has unusually high levels of CO.”

In addition to the many ground-based and space-based telescopes that will be on the lookout for interstellar asteroids and comets in the future, there is also compelling evidence that many interstellar objects that arrived in the past ended up staying here. There are even proposals in place to send a spacecraft to rendezvous with an interstellar object in the future, like the ESA’s Comet Interceptor.

[embedded content]

There’s no telling when the next interstellar comet or asteroid will pass through our Solar System, or whether or not we will be able to study it up-close using a spacecraft. One thing that is certain is that any future visitors will offer astronomers the opportunity to learn more about other star systems, like their compositions and how planets form within them.

The international team behind this study included members from the Laboratoire d’Etudes Spatiales et d’Instrumentation en Astrophysique (LESIA), the STAR Institute, the National Radio Astronomy Observatory (NRAO), the Institut de RAdioastronomie Millimétrique (IRAM), multiple universities, the NASA Jet Propulsion Laboratory and NASA HQ.

Since the team led by Cordiner and Milam made their observations, 2I/Borisov appears to have split into two objects (aka. “calving.”) This occurred in late March as the comet was making its way back into interstellar space. The venerable Hubble was able to catch a final glimpse of “Little Boris and Big Boris” as they departed our Solar System, perhaps never to be seen again.

Further Reading: NRAO, Nature

Let’s block ads! (Why?)



Source link

Continue Reading

Science

Tesla's Musk earns $770M in stock options, company confirms – Powell River Peak

Published

on


DETROIT — Tesla confirmed Thursday that CEO Elon Musk will get the first tranche worth nearly $770 million of a stock-based compensation package triggered by the company meeting several financial metrics.

The electric car and solar panel maker’s board certified that Musk earned the big payout, according to a filing with the U.S. Securities and Exchange Commission. The filing says Musk can buy 1.69 million shares of Tesla stock for $350.02 each, but it wasn’t clear whether he had exercised the stock options. His payout is based on the difference between the option price and Thursday’s closing share price of $805.81.

article continues below

Musk earned the options as part of an audacious compensation package approved by the board in 2018.

According to the filing, the board certified that Tesla had reached the milestones by hitting $20 billion in total revenue for four previous quarters and a total market value of $100 billion. The company also reached $1.5 billion in adjusted pretax earnings, but that must still be certified by the board, the filing said.

Musk has to hold the stock for a minimum of five years, under the terms of the compensation package.

Musk can afford to wait before cashing in on his latest windfall, given his wealth is estimated at $39 billion by Forbes magazine.

All told, the incentives approved by Tesla’s board in 2018 consist of 20.3 million stock options that will be doled out in 12 different bundles if the company is able to reach progressively more difficult financial goals. It’s one of the biggest corporate pay packages in U.S. history.

In order for Musk to receive all 20.3 million stock options, Tesla will have to generate adjusted annual earnings of $14 billion on annual revenue of $175 billion coupled with a market value of $650 billion. In the past four quarters, Tesla, which is based in Palo Alto, California, has reported adjusted earnings totalling $3.6 billion on revenue totalling $26 billion.

Let’s block ads! (Why?)



Source link

Continue Reading

Science

SpaceX’s historic NASA astronaut launch debut on track for second attempt – Teslarati

Published

on



Rather than making history on May 27th, SpaceX’s highest-profile launch ever – Crew Dragon’s NASA astronaut launch debut – was scrubbed just minutes before liftoff by stormy Florida weather. Unfortunately, conditions appear to be even less favorable on Saturday and Sunday backup windows.

Weather trended well, until it didn’t

The day began with launch fans growing increasingly concerned about a system of low-pressure off of Florida’s northeast coast that strengthened into tropical storm Bertha – the second named storm before the official start of the Atlantic basin hurricane season on June 1st. As the day progressed, Bertha became less of a worry for SpaceX recovery and emergency abort drop zones as it moved further north up the coast eventually making landfall in South Carolina. Then the thunderstorms began firing up.

Hans Koenigsmann, vice president for build and flight reliability at SpaceX, looks at a monitor showing a live feed of a SpaceX Falcon 9 rocket carrying the company’s Crew Dragon spacecraft on the launch pad during the countdown for a launch attempt of NASA’s SpaceX Demo-2 mission. (Credit: NASA/Joel Kowsky)

Going into launch day launch weather officer, Mike McAleenan of the U.S. Space Force’s 45th Weather Squadron predicted a 60% chance of favorable launch weather conditions. That decreased slightly to 50% during the morning’s launch weather briefing. The 50/50 shot of Florida weather cooperating to get the launch off during the one-second long launch window opportunity remained the main concern for the rest of the day.

An ominous thunderstorm rolls over LC-39A ahead of SpaceX’s ultimately scrubbed first attempt to launch the Crew Dragon Demo-2 test flight on Wednesday, May 27th. (Credit: Richard Angle for Teslarati)

During the final thirty minutes of the countdown, many of the weather constraints that were holding up a green-light for launch from cleared up, but one last weather rule remained no-go. McAleenan stated over the internal weather communication loop during NASA’s live broadcast that if the launch window could’ve extended another 10 minutes, the weather would probably cooperate. This wasn’t the case, though. The launch attempt was ultimately aborted just 14 minutes shy of liftoff due to the “field mill” rule not clearing in time. The lightning field mill rule refers to a sophisticated electrical field system that spans the entire area of Kennedy Space Center and the surrounding area of Cape Canaveral responsible for continuously detecting the electrical charge of the atmosphere.

Protecting rockets from producing lightning

Rockets are not permitted to launch through an electrically charged atmosphere because of the possibility of what is called “triggered” lightning – lightning that is actually produced by a rocket bursting through an electrically charged atmosphere. Sending a rocket through an already unstable atmosphere can cause a disturbance, a lightning bolt, to be triggered. This phenomenon has the capability of being potentially dangerous for the rocket and, more importantly in this case, the occupants on board.

A very helpful infographic published by the 45th Weather Squadron regarding the natural and triggered lightning launch rules. (Credit: 45th Weather Squadron)

Demo-2, Round 2

Following a scrubbed first attempt, the 45th Weather Squadron released the L-3 (3 days until launch) forecast for the second attempt to send NASA astronauts Doug Hurley and Bob Behnken to the International Space Station. The prediction looked much like the one going into Wednesday’s attempt. On Thursday morning, May 28th, a new L-2 (2 days until launch) forecast was released showing very little change from the evening before.

SpaceX’s next attempt at a Demo-2 launch will occur on Saturday, May 30th, at 3:22:41pm EDT with another backup attempt scheduled for Sunday, May 31st at 3:00:07pm EDT. The outlook for the weather, however, looks much the same as it did for Wednesday. The 45th Weather Squadron is currently predicting only a 40% chance of favorable launching conditions on both days, and that’s just for the weather directly over LC-39A at the time of launch.

A L-3 weather forcast provided by the U.S. Space Force’s 45th Weather Squadron outlines a 40% chance of acceptable weather conditions at time of launch for SpaceX’s back-up attempt to lauch the first ever crewed mission, Demo-2, on Saturday, May 30th. (Credt: U.S. Space Force – 45th Weather Squadron)

The 45th Weather Squadron does not predict other conditions that can determine a scrub of launch including upper-level atmospheric winds capable of completely sheering apart a rocket at altitude, or weather conditions for booster recovery and the recovery zones needed to rescue the Dragon capsule in the event of an emergency abort scenario. SpaceX has its own team of professionals that work in tandem with the 45th Weather Squadron to monitor the conditions of the recovery and abort zones. SpaceX takes things into consideration like wave height and patterns to determine whether or not conditions are appropriate enough for crews to perform any and all recovery operations that may be needed.

For Saturday’s attempt, the SpaceX Demo-2 will once again face the challenges of precipitation and dangerous lightning producing anvil and cumulus clouds. Expect launch day to look much like it did during the first attempt on Wednesday. SpaceX will need to thread one seriously precise needle to pull off the most historic rocket launch in company history.

Check out Teslarati’s newsletters for prompt updates, on-the-ground perspectives, and unique glimpses of SpaceX’s rocket launch and recovery processes.

SpaceX’s historic NASA astronaut launch debut on track for second attempt




<!–

View Comments

–>

Let’s block ads! (Why?)



Source link

Continue Reading

Science

Tesla's Musk earns $770M in stock options, company confirms – OttawaMatters.com

Published

on


DETROIT — Tesla confirmed Thursday that CEO Elon Musk will get the first tranche worth nearly $770 million of a stock-based compensation package triggered by the company meeting several financial metrics.

The electric car and solar panel maker’s board certified that Musk earned the big payout, according to a filing with the U.S. Securities and Exchange Commission. The filing says Musk can buy 1.69 million shares of Tesla stock for $350.02 each, but it wasn’t clear whether he had exercised the stock options. His payout is based on the difference between the option price and Thursday’s closing share price of $805.81.

Musk earned the options as part of an audacious compensation package approved by the board in 2018.

According to the filing, the board certified that Tesla had reached the milestones by hitting $20 billion in total revenue for four previous quarters and a total market value of $100 billion. The company also reached $1.5 billion in adjusted pretax earnings, but that must still be certified by the board, the filing said.

Musk has to hold the stock for a minimum of five years, under the terms of the compensation package.

Musk can afford to wait before cashing in on his latest windfall, given his wealth is estimated at $39 billion by Forbes magazine.

All told, the incentives approved by Tesla’s board in 2018 consist of 20.3 million stock options that will be doled out in 12 different bundles if the company is able to reach progressively more difficult financial goals. It’s one of the biggest corporate pay packages in U.S. history.

In order for Musk to receive all 20.3 million stock options, Tesla will have to generate adjusted annual earnings of $14 billion on annual revenue of $175 billion coupled with a market value of $650 billion. In the past four quarters, Tesla, which is based in Palo Alto, California, has reported adjusted earnings totalling $3.6 billion on revenue totalling $26 billion.

The Associated Press

Let’s block ads! (Why?)



Source link

Continue Reading

Trending