Space and astronomy news
Space telescopes designed to observe distant planets need to be powerful, but they also need some method of blocking the light from the parent star, which completely washes out any dimmer objects orbiting it. A strategy from CU-Boulder professor Webster Cash would use a large, daisy-shaped space shield to block the light from the star. …
Even though our Solar System’s gas giants vary widely in size and mass, they do have something in common. Each planet is roughly 10,000 times more massive than the combined mass of all their moons. During planetary formation, rocky moons grew out of the solid material surrounding each planet. As these moons grew larger, leftover …
Continue reading “Gas Giants Gobbled Up Most of Their Moons”
If you could strip away all the gas from Jupiter and Saturn, what would you find inside? Inside gas giant planets, the pressures and temperatures are enormous, and not much can survive those conditions. Researchers at the University of Minnesota have calculated that crystals would dissolve, and would actually work like metals, facilitating the flow of electrons. This could help to explain the tremendous magnetic fields detected around gas giant planets.
NASA’s Spitzer Space Telescope has uncovered a hot extrasolar planet orbiting a nearby star. Planet HD 189733b orbits its parent star only 63 light-years from Earth, making it the closest extrasolar planet ever detected directly. It moves in an extremely tight orbit – less than 3% of the distance from the Earth to the Sun – completing a tour around its star in just over 2 days. And it’s scorching hot, reaching temperatures of 844 Celsius (about 1,551 Fahrenheit) on its surface.
Researchers at the Washington University in St. Louis have developed a “field guide” for planet hunters searching for other Earths. They modeled the chemistry of silicate vapour and steam rich environments, similar to the early stages when an Earthlike planet is forming. During this stage, the planet is covered with a magma ocean which vapourises. This is a very distinct moment in the lifetime of a planet, and should be detectable because silicon monoxide gas is easy to see in infrared and radio wavelengths.
One of the more productive telescopes in space is the tiny Canadian MOST satellite (Microvariability and Oscillations of Stars). Developed and maintained on a shoestring – $7 million USD – MOST is only the size of a suitcase, but it has a very sensitive instrument which can detect the variations in star brightness. MOST has been used to analyze recently discovered extrasolar planets as they pass in front of their parent stars, and even get some information about their atmospheres.
A new high-speed camera has been mounted to the European Southern Observatory’s Very Large Telescope in Chile. This ultra fast camera is called ULTRACAM, and it’s capable of recording some of the most rapid astronomical events. It’s capable of taking 500 pictures a second, so it will be used to watch any object that can change quite rapidly, like black holes, gamma ray bursts, white dwarfs or cataclysmic variables.
Canadian astronomers using the MOST (Microvariability & Oscillations of STars) Space Telescope have detected that a giant extrasolar planet has forced its parent star into a lock-step orbit. This interaction is between the star tau Bootis and its “hot Jupiter” planet discovered in 1997. MOST was able to detect subtle variations in the star’s brightness that correspond with the planet’s orbit. It’s likely that the planet has forced the outer layer of tau Bootis’ atmosphere so that it rotates to keep the same side facing.
Astronomers working with the Canadian Microvariability & Oscillations of STars (MOST) space telescope have been able to indirectly probe the atmosphere of a planet orbiting another star. The planet, HD209458b, was imaged earlier this year by NASA’s Spitzer space telescope; it’s a “hot jupiter”, orbiting very close to its parent star. MOST will watch how its parent star changes in brightness as the planet passes in front and behind, and should be able to provide details about its temperature, pressure, and even cloud cover.
Astronomers have discovered more than 150 planets orbiting distant stars, but only indirectly. Now an international team of researchers think they might have the first direct photograph of a planet orbiting another star. The image is of GQ Lupi, a young star located 400-500 light-years away. A dimmer object, potentially a planet, is located to the right of the star separated by 100 astronomical units (2.5 times the distance of the Sun to Pluto). Unfortunately, the astronomers haven’t been able to determine the mass of the object, so they can’t rule out that it might be a brown dwarf.