Like most big galaxies, the Milky Way is a cold-blooded cannibal, with a history of gobbling up smaller galaxies in order to maintain its lovely spiral figure. But, a few billion years from now, our cosmic home could meet its match with an equally hungry neighbor called Andromeda.
Andromeda, the nearest large galaxy to ours, is on a crash course to merge with the Milky Way about 4.5 billion years from now. How will the monstrous smash-up change the shapes of the participating galaxies? That’s anyone’s guess. But, given Andromeda’s size, astronomers know our neighbor is no slouch when it comes to playing galactic tug-of-war — and, according to new research published today (Oct. 2) in the journal Nature, Andromeda may have a far more cannibalistic past than scientists gave it credit for.
Using observations from five different telescopes, the study authors observed the diffuse halo of stars at the edge of Andromeda’s orbit and detected at least two clusters of stars with distinct trajectories and velocities that didn’t seem to match each other, or the rest of the galaxy. Based on the estimated ages of these clusters, the team determined they were the remnants of two ancient dwarf galaxies that Andromeda had devoured long ago — one, gobbled up just a few billion years ago, and the other swallowed nearly 10 billion years ago.
Scientists have detected new types of organic compounds in the plumes that have been erupting from Saturn’s icy moon Enceladus.
NASA’s Cassini spacecraft collected invaluable data and images of Saturn and its moons over the approximately 20 years that the mission took place. While the mission ended on Sept. 15, 2017, with the craft diving toward the planet in a “Grand Finale,” scientists continue to study the wealth of data that they gathered during the mission.
In one new study, scientists looked at the material that Enceladus ejects from its core using hydrothermal vents. The material mixes with water in the moon’s subsurface ocean and is then emitted as water vapor and icy grains.
In Photos: Enceladus, Saturn’s Icy, Shiny Moon
Related: Saturn’s Moon Enceladus Is Likely the ‘Perfect Age’ to Harbor Life
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In studying these ejections, the team found organic molecules that are condensed onto these grains and which contain oxygen and nitrogen. This comes after the first discovery of organics on the moon in 2018.
Similar compounds on Earth take part in the chemical reactions that form amino acids, which are the organic compounds that combine to form proteins and are essential to life as we know it.
On Earth, energy, or heat, from hydrothermal vents on the ocean floor helps to fuel these amino acid-producing reactions. With these findings, scientists have suggested that perhaps something similar is happening on Enceladus and the hydrothermal vents under its subsurface ocean are aiding in the creation of amino acids on the moon.
“If the conditions are right, these molecules coming from the deep ocean of Enceladus could be on the same reaction pathway as we see here on Earth. We don’t yet know if amino acids are needed for life beyond Earth, but finding the molecules that form amino acids is an important piece of the puzzle,” Nozair Khawaja, who led the research team from the Free University of Berlin, said in a statement.
Now, the discovery of these organic compounds in no way equates to the discovery of life or even necessarily the building blocks of life. But it is another step in the direction of discovering whether or not amino acids might form on Enceladus and what that might mean with regard to the search for life in the universe.
“Here we are finding smaller and soluble organic building blocks — potential precursors for amino acids and other ingredients required for life on Earth,” co-author Jon Hillier said in the statement.
“This work shows that Enceladus’ ocean has reactive building blocks in abundance, and it’s another green light in the investigation of the habitability of Enceladus,” co-author Frank Postberg added in the same statement.
To detect these compounds and come to this exciting conclusion, Khawaja’s team used data from Cassini’s Cosmic Dust Analyzer (CDA), which detected ice grains emitted in the moon’s plumes; and data from the CDA’s spectrometer, which analyzed the composition of the grains.
These findings were published Oct. 2 in the journal the Monthly Notices of the Royal Astronomical Society.
Saturn Moon Enceladus Is First Alien ‘Water World’ with Complex Organics
Could Methane on Saturn’s Moon Enceladus Be a Sign of Life?
Hydrothermal Vent Experiments Bring Saturn Moon Enceladus to Earth
Goodness gracious! Great balls of fire rained from the sky in Chile last week, and officials are still trying to figure out what they were and where they came from.
One thing is certain: The mysterious burning objects were not meteors, according to news reports.
The fiery UFOs descended on Dalcahue City on the Chilean island of Chiloé on Sept. 25, CNET reported. . The tumbling objects crash-landed in seven locations, setting off fires that were promptly put out by volunteer firefighters. .
Related: 7 Things Most Often Mistaken for UFOs
Chiloé island resident Bernardita Ojeda had one fireball land on her property, where the flames ignited a few bushes, Ojeda told local news station Channel 2.
Geologists from Chile’s National Geology and Mining Service soon arrived to examine the seven sites that had been scorched by the falling space stuff. While they conducted their analyses, the story spread through local news, social media and national outlets.
Chilean astronomer and astrophysicist José Maza told Chilean news network TVN that the blazing bodies were likely either meteorites or space debris that had detached from rockets or satellites, according to CNET. On Sept. 26, astronomer Jonathan McDowell of the Harvard-Smithsonian Center for Astrophysics chimed in on Twitter, saying that the falling objects were probably meteorites and that there were “no obvious space debris candidates that [he could] see.”
“But [it] sometimes takes a few days for relevant data to come in,”
American Airlines frequent fliers will lose one of their biggest perks next year: the ability to earn and cash-in miles on each other’s flights.
The American-Alaska program partnership has become wobbly in recent years, but starting March 1, 2020 the two airlines will implement cuts that will gut their long-standing partnership even more.
Alaska Airlines is the second largest carrier at SFO; American Airlines is the third largest. (See the full list of ranked SFO airlines here.) Both have significant presence at Oakland and San Jose airports, too.
Alaska Airlines MileagePlan members will no longer be able to redeem their miles for flights on American Airlines international flights. This is in addition to similar restrictions on redemptions for domestic AA flights that went into effect in early 2018.
Alaska fliers will also not be able to earn miles when flying on American’s domestic and international flights come March 1. (See Alaska’s statement here.)
This cuts both ways: American Airlines says AAdvantage fliers will no longer earn miles when flying Alaska Airlines and Horizon Air domestic and international flights either.
There is an exception here, though. Miles can still be earned on codeshare flights, where both American and Alaska have placed their respective flight numbers on the flight. Those codeshare flights are few and far between and are mainly hops within the Midwest and East Coast.
Alaska Airlines is telling MileagePlan members that if they want to earn miles for flying on an American Airlines international flight, travel must be done by February 29, 2020. Flights booked before October 2 for travel after February 29, 2020 are still eligible for credit, but you’ll need to contact Alaska directly to get those miles. Alaska warns there cannot be any changes to American Airlines award travel after that date. So consider yourself warned, and get traveling!
Why the change?
American Airlines said the cuts were implemented after a “review of its airline partners and programs.”
Photo: Wilfredo Lee, Associated Press
Alaska Airlines and American Airlines loyalty partnership is taking a hit
“Starting March 1, Alaska Airlines Mileage Plan members will no longer be able to redeem miles on American Airlines flights, which will enable more award seats for AAdvantage members, particularly in the premium cabin between our domestic hubs and Seattle and Portland in the Pacific Northwest,” a spokesperson said.
The airline said many of the mileage redemptions by Alaska fliers were for seats in American’s first and business class cabins. American also said many of its members were redeeming AAdvantage miles for Alaska flights in a market that American already served.
With the merger of Alaska and Virgin America completed, industry observers said the combined Alaska Airlines network competed rather than complimented American Airlines, resulting in this latest round of partnership cuts.
When the partnership was formed, American helped Alaska fill the gaps in the South and on the East Coast where it had holes in its network, and Alaska helped American fill gaps on the West Coast — where it wasn’t as dominant.
But, American is aiming to grow its West Coast presence by building up its only hub at Los Angeles International Airport, where Alaska Airlines also has a big presence.