Hubble Space Telescope
How NASA’s Spitzer Has Stayed Alive for So Long
Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
calla.e.cofield@jpl.nasa.gov
After nearly 16 years of exploring the cosmos in infrared light, NASA’s Spitzer Space Telescope will be switched off permanently on Jan. 30, 2020. By then, the spacecraft will have operated for more than 11 years beyond its prime mission, thanks to the Spitzer engineering team’s ability to address unique challenges as the telescope slips farther and farther from Earth.
Managed and operated by NASA’s Jet Propulsion Laboratory in Pasadena, California, Spitzer is a small but transformational observatory. It captures infrared light, which is often emitted by “warm” objects that aren’t quite hot enough to radiate visible light. Spitzer has lifted the veil on hidden objects in nearly every corner of the universe, from a new ring around Saturn to observations of some of the most distant galaxies known. It has spied stars in every stage of life, mapped our home galaxy, captured gorgeous images of nebulas and probed newly discovered planets orbiting distant stars.
New Clues About How Ancient Galaxies Lit up the Universe
Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
calla.e.cofield@jpl.nasa.gov
NASA’s Spitzer Space Telescope has revealed that some of the universe’s earliest galaxies were brighter than expected. The excess light is a byproduct of the galaxies releasing incredibly high amounts of ionizing radiation. The finding offers clues to the cause of the Epoch of Reionization, a major cosmic event that transformed the universe from being mostly opaque to the brilliant starscape seen today.
In a new study (Royal Astronomical Society), researchers report on observations of some of the first galaxies to form in the universe, less than 1 billion years after the big bang (or a little more than 13 billion years ago). The data show that in a few specific wavelengths of infrared light, the galaxies are considerably brighter than scientists anticipated. The study is the first to confirm this phenomenon for a large sampling of galaxies from this period, showing that these were not special cases of excessive brightness, but that even average galaxies present at that time were much brighter in these wavelengths than galaxies we see today.
SPACE-TIME: The Missing Mass Mystery
By George McGinn
Cosmology and Space Research Institute
I don’t believe in Dark Matter or Dark Energy. Even the new Dark Flow.
ESA: Lensed Supernova Gives Insight to Expansion of Universe
Ariel Goobar & Rahman Amanullah
Oskar Klein Centre at Stockholm University, Stockholm, Sweden
An international team, led by astronomers from the Stockholm University, Sweden, has discovered a distant type Ia supernova, called iPTF16geu [1] — it took the light 4.3 billion years to travel to Earth [2]. The light from this particular supernova was bent and magnified by the effect of gravitational lensing so that it was split into four separate images on the sky [3]. The four images lie on a circle with a radius of only about 3000 light-years around the lensing foreground galaxy, making it one of the smallest extragalactic gravitational lenses discovered so far. Its appearance resembles the famous Refsdal supernova, which astronomers detected in 2015 (heic1525). Refsdal, however, was a core-collapse supernova.
Type Ia supernovae always have the same intrinsic brightness, so by measuring how bright they appear astronomers can determine how far away they are. They are therefore known as standard candles. These supernovae have been used for decades to measure distances across the Universe, and were also used to discover its accelerated expansion and infer the existence of dark energy. Now the supernova iPTF16geu allows scientists to explore new territory, testing the theories of the warping of spacetime on smaller extragalactic scales than ever before.
Ancient Stardust Sheds Light on the First Stars
This research was presented in a paper entitled “Dust in the Reionization Era: ALMA Observations of a z =8.38 Gravitationally-Lensed Galaxy”
by Laporte et al., to appear in The Astrophysical Journal Letters.
An international team of astronomers, led by Nicolas Laporte of University College London, have used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe A2744_YD4, the youngest and most remote galaxy ever seen by ALMA. They were surprised to find that this youthful galaxy contained an abundance of interstellar dust — dust formed by the deaths of an earlier generation of stars.
Follow-up observations using the X-shooter instrument on ESO’s Very Large Telescope confirmed the enormous distance to A2744_YD4. The galaxy appears to us as it was when the Universe was only 600 million years old, during the period when the first stars and galaxies were forming [1].
Hubble Finds Big Brother of Halley’s Comet – Ripped Apart By White Dwarf
February 9, 2017
European Space Agency News Release
Siyi Xu
European Southern Observatory
Garching bei München, Germany
Mathias Jäger
ESA/Hubble, Public Information Officer
Garching, Germany
The international team of astronomers observed the white dwarf WD 1425+540, about 170 light-years from Earth in the constellation Boötes (the Herdsman) [1]. While studying the white dwarf’s atmosphere using both the NASA/ESA Hubble Space Telescope and the W. M. Keck Observatory the team found evidence that an object rather like a massive comet was falling onto the star, getting tidally disrupted while doing so.
The team determined that the object had a chemical composition similar to the famous Halley’s Comet in our own Solar System, but it was 100,000 times more massive and had twice the proportion of water as its local counterpart. Spectral analysis showed that the destroyed object was rich in the elements essential for life, including carbon, oxygen, sulphur and even nitrogen [2].
Celestial Cat Meets Cosmic Lobster
Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Astronomers have for a long time studied the glowing, cosmic clouds of gas and dust catalogued as NGC 6334 and NGC 6357, this gigantic new image from ESO’s Very Large Telescope Survey Telescope being only the most recent one. With around two billion pixels this is one of the largest images ever released by ESO. The evocative shapes of the clouds have led to their memorable names: the Cat’s Paw Nebula and the Lobster Nebula, respectively. Credit: ES
NGC 6334 is located about 5500 light-years away from Earth, while NGC 6357 is more remote, at a distance of 8000 light-years. Both are in the constellation of Scorpius (The Scorpion), near the tip of its stinging tail.
The British scientist John Herschel first saw traces of the two objects, on consecutive nights in June 1837, during his three-year expedition to the Cape of Good Hope in South Africa. At the time, the limited telescopic power available to Herschel, who was observing visually, only allowed him to document the brightest “toepad” of the Cat’s Paw Nebula. It was to be many decades before the true shapes of the nebulae became apparent in photographs — and their popular names coined.
The three toepads visible to modern telescopes, as well as the claw-like regions in the nearby Lobster Nebula, are actually regions of gas — predominantly hydrogen — energised by the light of brilliant newborn stars. With masses around 10 times that of the Sun, these hot stars radiate intense ultraviolet light. When this light encounters hydrogen atoms still lingering in the stellar nursery that produced the stars, the atoms become ionised. Accordingly, the vast, cloud-like objects that glow with this light from hydrogen (and other) atoms are known as emission nebulae.
Water Vapor Plumes Discovered on Jupiter’s Moon Europa
Written by George McGinn
Cosmology and Space Research
September 27, 2016 at 4:32pm EST
In one of the most promising places in the Solar System where life may exist, astronomers using NASA’s Hubble Space Telescope have photographed what appears to be water vapor plumes escaping Jupiter’s moon Europa.
The team from the Space Telescope Science Institute (STScI) in Baltimore saw finger-like projections when viewing Europa as it past in front of Jupiter, according to team leader William Sparks.
The discovery occurred by accident as the team’s original proposal was to observe Europa to determine if it had an atmosphere or exosphere.
An exosphere of neon was detected on Earth’s Moon on August 17, 2015 based on study the data from the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft.
NASA Extends Hubble Space Telescope Science Operations Contract
This action will extend the period of performance from July 1 through June 30, 2021. The contract value will increase by approximately $196.3 million for a total contract value of $2.03 billion.
This contract extension covers the work necessary to continue the science program of the Hubble mission by the Space Telescope Science Institute. The support includes the products and services required to execute science system engineering, science ground system development, science operations, science research, grants management and public outreach support for Hubble and data archive support for missions in the Mikulski Archive for Space Telescopes.
After the final space shuttle servicing mission to the telescope in 2009, Hubble is better than ever. Hubble is expected to continue to provide valuable data into the 2020’s, securing its place in history as an outstanding general purpose observatory in areas ranging from our solar system to the distant universe.
In 2018, NASA’s James Webb Space Telescope will be launched into space as the premier observatory of the next decade, serving astronomers worldwide to build on Hubble’s legacy of discoveries and help unlock some of the biggest mysteries of the universe.
For information about NASA and agency programs, visit: http://www.nasa.gov
Cloudy Days on Exoplanets May Hide Atmospheric Water
Water is a hot topic in the study of exoplanets, including “hot Jupiters,” whose masses are similar to that of Jupiter, but which are much closer to their parent star than Jupiter is to the sun. They can reach a scorching 2,000 degrees Fahrenheit (1,100 degrees Celsius), meaning any water they host would take the form of water vapor.
Astronomers have found many hot Jupiters with water in their atmospheres, but others appear to have none. Scientists at NASA’s Jet Propulsion Laboratory, Pasadena, California, wanted to find out what the atmospheres of these giant worlds have in common.
Researchers focused on a collection of hot Jupiters studied by NASA’s Hubble Space Telescope. They found that the atmospheres of about half of the planets were blocked by clouds or haze.
“The motivation of our study was to see what these planets would be like if they were grouped together, and to see whether they share any atmospheric properties,” said Aishwarya Iyer, a JPL intern and master’s degree candidate at California State University, Northridge, who led the study.
The new study, published in the June 1 issue of the Astrophysical Journal, suggests that clouds or haze layers could be preventing a substantial amount of atmospheric water from being detected by space telescopes. The clouds themselves are likely not made of water, as the planets in this sample are too hot for water-based clouds.
“Clouds or haze seem to be on almost every planet we studied,” Iyer said. “You have to be careful to take clouds or haze into account, or else you could underestimate the amount of water in an exoplanet’s atmosphere by a factor of two.”
In the study, scientists looked at a set of 19 hot Jupiters previously observed by Hubble. The telescope’s Wide Field Camera 3 had detected water vapor in the atmospheres of 10 of these planets, and no water on the other nine. But that information was spread across more than a dozen studies. The methods of analyzing and interpretation varied because the studies were conducted separately. There had not been one overarching analysis of all these planets.
To compare the planets and look for patterns, the JPL team had to standardize the data: Researchers combined the datasets for all 19 hot Jupiters to create an average overall light spectrum for the group of planets. They then compared these data to models of clear, cloud-free atmospheres and those with various cloud thicknesses.
The scientists determined that, for almost every planet they studied, haze or clouds were blocking half of the atmosphere, on average.
“In some of these planets, you can see water peeking its head up above the clouds or haze, and there could still be more water below,” Iyer said.
Scientists do not yet know the nature of these clouds or hazes, including what they are they made of.
“Clouds or haze being on almost all these planets is pretty surprising,” said Robert Zellem, a postdoctoral fellow at JPL and co-author of the study.
The implications of this result agree with findings published in the Dec. 14, 2015, issue of the journal Nature. The Nature study used data from NASA’s Hubble and Spitzer Space Telescopes to suggest that clouds or haze could be hiding undetected water in hot Jupiters. This new study uses exoplanet data from a single instrument on Hubble to uniformly characterize a larger group of hot Jupiters, and is the first to quantify how much of the atmosphere would be shielded as a result of clouds or haze.
The new research could have implications for follow-up studies with future space observatories, such as NASA’s James Webb Space Telescope. Exoplanets with thick cloud covers blocking the detection of water and other substances may be less desirable targets for more extensive study.
These results are also important for figuring out how planets form, scientists say.
“Did these planets form in their current positions or migrate toward their host stars from farther out? Understanding the abundances of molecules such as water helps us answer those questions,” Zellem said.
“This paper is an exciting step forward for the study of exoplanets and comparing their properties,” said Mark Swain, study co-author and group supervisor for the exoplanet discovery and science group at JPL.
Michael Line of the University of California, Santa Cruz, also contributed to the study. Other co-authors from JPL included Gael Roudier, Graca Rocha and John Livingston.
For more information about the Hubble Space Telescope, visit: www.nasa.gov/hubble.
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