Institute of Astronomy

Astronomy News

Asteroid 2023 BU: Space rock passes closer than some satellites

3 hours 54 min ago

About the size of a bus, the space rock whipped over the southern tip of South America.

Weird supernova remnant blows scientists’ minds

3 hours 54 min ago

Nature, Published online: 26 January 2023; doi:10.1038/d41586-023-00202-1

Fireworks display from rare dying star is unlike anything astronomers have seen.

NASA’s Fermi Detects First Gamma-Ray Eclipses From ‘Spider’ Star Systems

3 hours 55 min ago
Portal origin URL: NASA’s Fermi Detects First Gamma-Ray Eclipses From ‘Spider’ Star SystemsPortal origin nid: 485227Published: Thursday, January 26, 2023 - 11:00Featured (stick to top of list): noPortal text teaser: Scientists have discovered the first gamma-ray eclipses from a special type of binary star system using data from NASA’s Fermi Gamma-ray Space Telescope.Portal image: Streams of material blow off an orange-yellow in the foreground. In the distance, a pulsar rotates like a lighthouse, emitting beams of magenta light. The background is black, purple, and speckled with stars.

‘Forbidden’ planet somehow escaped consumption by its dying host star

3 hours 55 min ago

The planet 8 Ursae Minoris b should have been destroyed when its star became a red giant, but it continues to orbit strangely close to the star

Supernovae might be a good place to hunt for alien broadcasts

3 hours 55 min ago

Other intelligent civilisations may send transmissions after a bright galactic event like a supernova to make them more visible to others, according to SETI researchers

Meteorite results bode well for exo-Earths

3 hours 57 min ago
Science, Volume 379, Issue 6630, Page 318-319, January 2023.

NASA’s Webb Telescope Receives Top Space Foundation Award

26 January 2023 - 9:42am
Portal origin URL: NASA’s Webb Telescope Receives Top Space Foundation AwardPortal origin nid: 485216Published: Wednesday, January 25, 2023 - 09:30Featured (stick to top of list): noPortal text teaser: NASA’s James Webb Space Telescope team has been selected to receive the 2023 John L. “Jack” Swigert, Jr., Award for Space Exploration, a top award from the Space Foundation. This annual award honors a space agency, company, or consortium of organizations in the realm of space exploration and discovery.Portal image: The James Webb Space Telescope with primary mirror fully unfolded in cleanroom

NASA’s Lucy Team Announces New Asteroid Target

26 January 2023 - 9:42am
Portal origin URL: NASA’s Lucy Team Announces New Asteroid TargetPortal origin nid: 485217Published: Wednesday, January 25, 2023 - 11:55Featured (stick to top of list): noPortal text teaser: NASA’s Lucy spacecraft will add another asteroid encounter to its 4-billion-mile journey. On Nov. 1, 2023, Lucy will get a close-up view of a small main-belt asteroid to conduct an engineering test of the spacecraft’s innovative asteroid-tracking navigation system.Portal image: A diagram of the solar system, with the Sun a small yellow dot just off-center and Mercury, Venus, Earth, and Mars' orbits represented by colorful circles. The Lucy mission's blue orbit intersects with asteroid 1999 VD57's pink orbit.

Rare green comet C/2022 E3 is about to make its closest pass by Earth

26 January 2023 - 9:42am

A comet that last passed by Earth about 50,000 years ago is coming around again and will make its closest pass on 2 February, at which point it may be visible with the naked eye

Webb telescope hunts life's icy chemical origins

25 January 2023 - 9:47am

The new super space telescope has been studying some of the darkest, coldest regions of space.

Applied technology will block light from multi-star systems to search for Earth-like planets

25 January 2023 - 9:46am
PROJECT

Multi-star Wavefront Control (MSWC)

SNAPSHOT

Multi-star wavefront control technology enables imaging planets in systems with multiple suns (such as Alpha Centauri, the nearest star system to us) and searching them for signs of life.

In 1990, at the behest of Carl Sagan, the Voyager mission took a photo of Earth from 3.7 billion miles away (image at left). The next challenge is to take a similar image of an Earth-like planet orbiting another star. MSWC technology could enable images of multi-star systems such as Alpha Centauri (simulated image on the right; image credit: J. Males, University of Arizona), the nearest star system to the Sun that could potentially host such planets.

For millennia, people have wondered if life exists elsewhere in the universe. To answer this question, we need to directly image exoplanets (planets orbiting stars other than the Sun) and search them for signs of life. Many nearby stars, however, reside in multi-star systems (i.e., systems with more than one star). In fact, Sun-like stars are more likely to be in multi-star systems—such as Alpha Centauri, the nearest star system to the Sun—than be single stars like our Sun. Therefore, to detect life we will likely need to image exoplanets in these multi-star systems. A newly developed technology, Multi-Star Wavefront Control (MSWC), provides just this kind of capability.

Planets are much dimmer than stars and typically light from nearby stars must be suppressed to image them. Broadly speaking, instruments that suppress starlight inside the telescope are called coronagraphs and those that do it externally are called starshades.

NASA’s next flagship telescope will be the Nancy Grace Roman Space Telescope, scheduled to launch by May 2027, and will include a technology demonstration of a coronagraphic instrument capable of imaging large planets near their host stars. NASA is also embarking on the development of the next flagship after Roman, provisionally named the “Habitable Worlds Observatory.” Recommended by the 2020 Decadal Survey in Astronomy and Astrophysics, this flagship will address the guidance to identify at least 25 Earth-like planets and characterize them for evidence of life. In addition, NASA may select smaller missions that support the objective of discovering and characterizing habitable planets.

Although binary stars are scientifically a very attractive class of targets for such missions (especially Alpha Centauri), they present a technical challenge because light from both stars needs to be suppressed to image any nearby planets. Using a combination of a coronagraph and/or starshade to suppress light from each star is not optimal because of the added cost and risk. In addition, current coronagraphic systems can suppress starlight around an individual star, but cannot suppress the cross-contamination of starlight between stars. Eliminating this cross-contamination is the key challenge that must be overcome to image planets around binary star systems.

Multi-Star Wavefront Control (MSWC) was developed to address this challenge. Invented at NASA Ames in 2014, it relies on two innovations that work together. The first is a way to control a deformable mirror (DM) to suppress light from two stars independently. This is done by using two different sets of shapes (spatial frequency modes) on the DM for different stars. The second technique, called “super-Nyquist wavefront control,” is a way to enable deformable mirrors to suppress starlight beyond their normal limits by using a special "mild grating,” shown as a grid of blue dots in the image below. Normally, a DM can only suppress starlight in a small region around a star, like a single tent pole (the star) supporting a small tent (DM control region). This poses a problem when imaging binary stars, because a typical DM can only suppress starlight from both stars if those stars’ two regions overlap. However, binary stars tend to be far apart, so there is no overlap, like two small tents that are far away from each other. The mild grating solves this problem by creating a grid of faint copies of the second star (so-called “diffraction orders”), extending the reach of the DM to a much larger region around each star, similar to how a grid of tent poles can support a larger tent than a single pole. Using these two techniques, a coronagraph can overcome cross-contamination and increase the starlight contrast to image exoplanets in binary star systems.

Left: Microscope image of an optical mask that enables suppression of stars in multi-star systems to reveal planets in such systems. Middle and right: the enabling element is a grid of dots (mild grating), shown in this design image at different zoom levels.

Because deformable mirrors will be present in essentially all future coronagraphic mission concepts, MSWC is compatible with most of them, without requiring a major instrument redesign. This compatibility enabled MSWC to be accepted as a contributed mode on the Roman Space Telescope’s Coronagraph Instrument, with only slight modifications of the single-star instrument masks. Testing MSWC on the sky with Roman’s coronagraph will demonstrate this important technology to enable imaging of exoplanets in binary star systems, and has the potential to detect planets around binaries like Alpha Centauri.

The MSWC team has been steadily maturing the technology through simulations as well as demonstrations at the Ames Coronagraph Experiment Laboratory and on the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument on the Subaru Telescope—a ground-based telescope operated by the National Astronomical Observatory of Japan. Also, over the past few years, the team extended MSWC testing to the High Contrast Imaging Testbed (HCIT) at NASA’s Jet Propulsion Laboratory (JPL), a state-of-the-art facility for high-contrast demonstrations in vacuum.

Team members working at the High Contrast Imaging Testbed (HCIT) facility at NASA’s JPL. Pictured left to right: Eduardo Bendek, Ruslan Belikov, Dan Sirbu, and David Marx. The goal of these tests is to perform a vacuum demonstration of the MSWC technology by suppressing the glare of more than one star to reveal dim planets that are otherwise hidden.

MSWC has made significant strides, demonstrating the basic feasibility of suppressing starlight from more than one star, as well as doing so for stars that are separated beyond the conventional limits of deformable mirrors. Now, the team is hard at work to increase the performance, ultimately to levels required for detecting Earthlike planets.

“Just imagine -- when you go outside and look at a star in the night sky, you might be looking at a planet just like the Earth, hidden in the star’s glare,” said Ruslan Belikov, the project lead for MSWC. “Also, chances are that the star you’re looking it is a multi-star system. I just can’t wait until we lift veils of starlight to unlock the secrets that lie on the planets within.”

Acknowledgment: This work was supported by NASA Internal Scientist Funding Model (ISFM) program and led by the NASA Ames Research Center. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).

PROJECT LEADS

Dr. Ruslan Belikov, NASA Ames Research Center (Principal Investigator) and Dr. Eduardo Bendek (Institutional PI), NASA Jet Propulsion Laboratory.

SPONSORING ORGANIZATION

NASA Astrophysics Division (Internal Scientist Funding Model/ Strategic Astrophysics Technology [SAT])

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Rare Antarctic meteorite is one of the largest ever found

25 January 2023 - 9:46am

Antarctica is the perfect place to go meteorite hunting, as space rocks stand out on the wide fields of ice, and researchers have found a new crop

Webb Unveils Dark Side of Pre-stellar Ice Chemistry

24 January 2023 - 9:50am
Portal origin URL: Webb Unveils Dark Side of Pre-stellar Ice ChemistryPortal origin nid: 485155Published: Monday, January 23, 2023 - 11:00Featured (stick to top of list): noPortal text teaser: An international team of astronomers using NASA’s James Webb Space Telescope has obtained an in-depth inventory of the deepest, coldest ices measured to date in a molecular cloud.Portal image: A black background filled with galaxies in shades of a red, orange and blue. In the foreground are blue smokey wisps. On the left top, the wisps are orange and white. Four bright points of light, three orange and one a white-orange mix at the bottom left.

JWST has seen building blocks of life in a dark, cold cloud in space

24 January 2023 - 9:49am

The James Webb Space Telescope has observed a frigid cloud of dust and gas where stars are forming, and it found frozen elements that are crucial for the development of life

Winchcombe meteorite: Is this the UK's most important fireball?

23 January 2023 - 9:43am

The meteorite crashed in England in 2021, containing water that was a near-perfect match for that on Earth.

Why the Hubble telescope is still in the game — even as JWST wows

23 January 2023 - 9:42am

Nature, Published online: 20 January 2023; doi:10.1038/d41586-023-00136-8

NASA’s nearly 33-year-old observatory still has plenty of top science to do, and astronomers want to extend its lifetime.

Hubble Captures Cosmic Treasure Trove

23 January 2023 - 9:41am
Portal origin URL: Hubble Captures Cosmic Treasure TrovePortal origin nid: 485110Published: Friday, January 20, 2023 - 08:00Featured (stick to top of list): noPortal text teaser: A host of astronomical objects are scattered across this image from the NASA/ESA Hubble Space Telescope. Background galaxies ranging from stately spirals to fuzzy ellipticals are strewn across the image.Portal image: Black field with with galaxies. Center of image holds a diffuse collection of stars, the galaxy UGC 7983. Upper Left: four distinct vertical streaks, alternating rust-red and blue, form a dashed line. The signature of the photobombing asteroid.

Amazing JWST images show a nebula shaped by a multi-star smash-up

23 January 2023 - 9:41am

The stunning filaments and coils of light that make up the Southern Ring Nebula were shaped by as many as five stars all orbiting one another in a complex dance