Image (Credit): Hubble image of a triple-star system. (NASA, ESA, G. Duchene (Universite de Grenoble I); Image Processing: Gladys Kober (NASA/Catholic University of America))
This week’s image is from the NASA/ESA Hubble Space Telescope. It shows a triple-star system that consists of the variable star HP Tau, HP Tau G2, and HP Tau G3.
HP Tau is known as a T Tauri star, a type of young variable star that hasn’t begun nuclear fusion yet but is beginning to evolve into a hydrogen-fueled star similar to our Sun. T Tauri stars tend to be younger than 10 million years old ― in comparison, our Sun is around 4.6 billion years old ― and are often found still swaddled in the clouds of dust and gas from which they formed.
Image (Credit): The Little Dumbell Nebula as captured by the Hubble Space Telescope. (NASA, ESA, STScI)
This week’s image comes from the NASA/European Space Agency’s Hubble Space Telescope. It shows what is called the Little Dumbbell Nebula, more formally called Messier 76, M76, or NGC 650/651, which is about 3,400 light-years away. The image is being shared as part of the celebration of Hubble’s 34th anniversary, which is discussed in this video.
M76 is classified as a planetary nebula, an expanding shell of glowing gases that were ejected from a dying red giant star. The star eventually collapses to an ultra-dense and hot white dwarf. A planetary nebula is unrelated to planets, but have that name because astronomers in the 1700s using low-power telescopes thought this type of object resembled a planet.
M76 is composed of a ring, seen edge-on as the central bar structure, and two lobes on either opening of the ring. Before the star burned out, it ejected the ring of gas and dust. The ring was probably sculpted by the effects of the star that once had a binary companion star. This sloughed off material created a thick disk of dust and gas along the plane of the companion’s orbit. The hypothetical companion star isn’t seen in the Hubble image, and so it could have been later swallowed by the central star. The disk would be forensic evidence for that stellar cannibalism.
The primary star is collapsing to form a white dwarf. It is one of the hottest stellar remnants known at a scorching 250,000 degrees Fahrenheit, 24 times our Sun’s surface temperature. The sizzling white dwarf can be seen as a pinpoint in the center of the nebula. A star visible in projection beneath it is not part of the nebula.
Pinched off by the disk, two lobes of hot gas are escaping from the top and bottom of the “belt,” along the star’s rotation axis that is perpendicular to the disk. They are being propelled by the hurricane-like outflow of material from the dying star, tearing across space at two million miles per hour. That’s fast enough to travel from Earth to the Moon in a little over seven minutes! This torrential “stellar wind” is plowing into cooler, slower-moving gas that was ejected at an earlier stage in the star’s life, when it was a red giant. Ferocious ultraviolet radiation from the super-hot star is causing the gases to glow. The red color is from nitrogen, and blue is from oxygen.
Given our solar system is 4.6 billion years old, the entire nebula is a flash in the pan by cosmological timekeeping. It will vanish in about 15,000 years.
ESA’s Mars Express recently looped around Mars for the 25,000th time – and the orbiter has captured yet another spectacular view of the Red Planet to mark the occasion. The new high-altitude view was taken by Mars Express’s High Resolution Stereo Camera (HRSC). It features many of Mars’s towering volcanoes and even includes a surprise appearance from the planet’s largest moon, Phobos.
A piece of metal came crashing through a home in Florida that is believed to be from a 5,800-pound battery pallet discarded by the International Space Station (ISS). Naples homeowner Alejandro Otero was on vacation when he received a call from his son, saying he heard a ‘tremendous sound’ and there were gaping holes in the ceiling and floor – while explaining whatever fell almost hit him. The two-pound, cylinder object has since been recovered by NASA to determine its origin and if found to be space junk, the agency could be liable for damages.
The White House on Tuesday directed NASA to establish a unified standard of time for the moon and other celestial bodies, as the United States aims to set international norms in space amid a growing lunar race among nations and private companies. The head of the White House Office of Science and Technology Policy (OSTP), according to a memo seen by Reuters, instructed the space agency to work with other parts of the U.S. government to devise a plan by the end of 2026 for setting what it called a Coordinated Lunar Time (LTC).
Scientists say Mars may have had more water and stayed wet for longer than they had previously estimated based on photos from NASA’s Curiosity rover. An international team of researchers led by Imperial College London recently found unusual formations in rock and sediment in unexpected places in the crater. The rocks allow scientists to compare the evolving geology of Mars with Earth.
Today, U.S. Senators Alex Padilla and Laphonza Butler (both D-Calif.) wrote to NASA Administrator Bill Nelson urging him to allocate the full $650 million necessary to fund the Mars Sample Return (MSR) mission in NASA’s FY24 spending plan. The Senators are issuing the letter following the passage of the FY 2024 appropriations package, which reiterated Congress’ strong commitment to the MSR mission.
A fresh, icy crust hides a deep, enigmatic ocean. Plumes of water burst through cracks in the ice, shooting into space. An intrepid lander collects samples and analyses them for hints of life. ESA has started to turn this scene into a reality, devising a mission to investigate an ocean world around either Jupiter or Saturn. But which moon should we choose? What should the mission do exactly? A team of expert scientists has delivered their findings...Aiming for transformational science, considering the characteristics of each moon and future planned missions to Jupiter and Saturn’s ocean worlds, the scientists identified Saturn’s moon Enceladus as the most compelling target, followed by Saturn’s moon Titan and then Jupiter’s moon Europa.
The two-tonne ERS-2 spacecraft burnt up in the atmosphere over the Pacific. So far, there have been no eyewitness accounts of the mission’s demise or of any debris reaching Earth’s surface. ERS-2 was one of a pair of missions launched by the European Space Agency in the 1990s to study the atmosphere, the land and the oceans in novel ways. The duo monitored floods, measured continental and ocean-surface temperatures, traced the movement of ice fields, and sensed the ground buckle during earthquakes.
Houston-based Intuitive Machines is targeting 5:49 p.m. EST on Thursday, February 22, to put its Odysseus lunar lander on the surface of the moon—and it will be streamed live on NASA TV on YouTube. The first U.S. commercial moon lander, Odysseus—also known by its nickname “Odie”—will touchdown near a crater called Malapert A in the south pole region of the moon. If successful, this IM-1 mission—which is taking a scientific payload to the moon—will be the first spacecraft from the U.S. to land on the moon since Apollo 17 in December 1972.
There may be a lot more than we thought to the belt of icy debris that circles the outer Solar System. Data from the New Horizons probe as it sails serenely through the Kuiper Belt hints at unexpected levels of particles where dust ought to be thinning out, suggesting the donut-shaped field extends significantly farther from the Sun than previous estimates suggest.
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