Thursday, June 8, 2023
Support Our Journalism
HomeScientiFixHow are stars like Sun formed? James Webb Space Telescope images hold...

How are stars like Sun formed? James Webb Space Telescope images hold key to new investigations

ScientiFix, our weekly feature, offers you a summary of the top global science stories of the week, with links to their sources.

Text Size:

New Delhi: Taking a “deep dive” into one of James Webb Space Telescope’s (JWST) iconic first images, scientists have discovered dozens of energetic jets and outflows from young stars previously hidden by dust clouds. The JWST is a partnership between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).

The discovery marks the beginning of a new era of investigating how stars like our Sun form, and how the radiation from nearby massive stars might affect the development of planets.

The Cosmic Cliffs, a region at the edge of a gigantic, gaseous cavity within the star cluster NGC 3324, is interesting to astronomers for being a hotbed for star formation.

The region has been well studied by the Hubble Space Telescope. However, many details of star formation in NGC 3324 remain hidden at visible-light wavelengths.

The JWST, on the other hand, is built to detect jets and outflows seen only in the infrared at high resolution. Its capabilities also allow researchers to track the movement of other features previously captured by Hubble.

Molecular hydrogen is a vital ingredient for making new stars and an excellent tracer of the early stages of their formation. As young stars gather material from the gas and dust that surround them, most also eject a fraction of that material back out again from their polar regions in jets and outflows. These jets then act like a snowplow, bulldozing into the surrounding environment. Visible in JWST observations is the molecular hydrogen getting swept up and excited by these jets.

Previous observations of jets and outflows looked mostly at nearby regions and more evolved objects that are already detectable in the visual wavelengths seen by Hubble. The unparalleled sensitivity of Webb allows observations of more distant regions, while its infrared optimisation probes into the dust-sampling younger stages. Together this provides astronomers with an unprecedented view into environments that resemble the birthplace of our solar system. Read more.

Also read: NASA’s InSight rover prepares to join Mars’s robot graveyard — ‘may be last image I send’

Ancient microbes, direct ancestors of complex life, grown in lab

For the first time, scientists have grown ancient microbes in the lab whose existence predates the rise of nucleus-carrying cells on Earth. This may hold the secrets to how such complex cells first came to be.

For the study, researchers grew an organism called Lokiarchaeum ossiferum, which belongs to a group of microbes known as Asgard archaea.

Named after the abode of the gods in Norse mythology, Asgard archaea are thought by some scientists to be the closest evolutionary relatives of eukaryotes, cells that package their DNA in a protective bubble called a nucleus.

On the evolutionary tree of life, Asgards often appear as a “sister” of eukaryotes, or as their direct ancestor. Asgards don’t carry nuclei themselves, but they carry genes and proteins that were once thought to be unique to eukaryotes.

Researchers have a variety of theories as to how Asgards may have gained primitive nuclei and thus birthed the first complex cells, which later gave rise to plants, animals and humans. Read more.

Scientists propose building futuristic space colonies on asteroids

Researchers at the University of Rochester have proposed a futuristic plan to develop large cities on asteroids that could feasibly allow humans to live in space.

In 1972 NASA commissioned physicist Gerard O’Neill to design a space habitat that could feasibly allow humans to live in space. O’Neill and his colleagues worked out a plan for “O’Neill cylinders”, spinning space metropolises consisting of two cylinders rotating in opposite directions, with a rod connecting the cylinders at each end.

The cylinders would rotate fast enough to provide artificial gravity on their inner surface, but slow enough that people living in them would not experience motion sickness. However, getting the required materials to build such structures on space made the plan cost prohibitive.

The team from Rochester worked on creating a plan for cost effective O’Neill cylinders, which have been featured on TV shows and movies including Star Trek and books such as Orson Scott Card’s 1985 novel Ender’s Game.

The team proposes that the asteroid would be enveloped by a giant mesh made of carbon nanotutbes and would be spun to create artificial gravity. This process would cause the asteroid to break apart. Bits of the asteroid rubble would fling outward, which would then expand the carbon nanofiber bag enveloping the asteroid.

When the bag reaches its maximum extent, the carbon nanofibers would snap taut, catching the expanding rubble. As the rubble settles against the bag, it would produce a layer thick enough to shield against radiation for anyone living inside.

The spin of the cylinder would induce artificial gravity on the inner surface.

Calculations by the University of Rochester researchers show that a 300-meter-diameter asteroid just a few football fields across could be expanded into a cylindrical space habitat with about 22 square miles of living area. Read more.

Now, a new cancer treatment using artificial DNA?

Researchers at the University of Tokyo have used artificial DNA to create a hairpin-shaped structure that can target and kill cancer cells. The method was effective in lab tests against human cervical cancer and breast cancer-derived cells, and against malignant melanoma cells from mice.

When the chemically synthesised DNA pairs were injected into cancer cells, they connected to microRNA (miRNA) molecules that are overproduced in certain cancers. Once connected to the miRNA, they unraveled and joined together, forming longer chains of DNA which triggered an immune response.

This response not only killed the cancer cells but prevented further growth of cancerous tissue. Read more.

(Edited by Poulomi Banerjee)

Also read: Scientists identify brain pattern for drug & food craving, can be used to diagnose addiction


Subscribe to our channels on YouTube & Telegram

Support Our Journalism

India needs fair, non-hyphenated and questioning journalism, packed with on-ground reporting. ThePrint – with exceptional reporters, columnists and editors – is doing just that.

Sustaining this needs support from wonderful readers like you.

Whether you live in India or overseas, you can take a paid subscription by clicking here.

Support Our Journalism

Most Popular