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European Satellite ERS-2 to Reenter Earth’s Atmosphere This Week

Universe Today - Mon, 02/19/2024 - 12:11pm

One of the largest reentries in recent years, ESA’s ERS-2 satellite is coming down this week.

After almost three decades in orbit, an early Earth-observation satellite is finally coming down this week. The European Space Agency’s (ESA) European Remote Sensing satellite ERS-2 is set to reenter the Earth’s atmosphere on or around Wednesday, February 21st.

A Trail Blazing Mission

Launched atop an Ariane-4 rocket from the Kourou Space Center in French Guiana on April 21st, 1995, ERS-2 was one of ESA’s first Earth observation satellites. ERS-2 monitored land masses, oceans, rivers, vegetation and the polar regions of the Earth using visible light and ultraviolet sensors. The mission was on hand for several natural disasters, including the flood of the Elbe River across Germany in 2006. ERS-2 ceased operations in September 2011.

Anatomy of the reentry of ERS-2. ESA

ERS-2 was placed in a retrograde, Sun-synchronous low Earth orbit, inclined 98.5 degrees relative to the equator. This orbit is typical for Earth-observing and clandestine spy satellites, as it allows the mission to image key target sites at the same relative Sun angle, an attribute handy for image interpretation.

ERS-2 tracks and ice floe. ESA The Last Days of ERS-2

Reentry predictions for the satellite are centered on February 21st at 00:19 Universal Time (UT)+/- 25 hours. As we get closer, expect that time to get refined. The mass of ERS-2 at launch (including fuel) was 2,516 kilograms. Expect most of the satellite to burn up on reentry.

The orbital path of ERS-2. Orbitron

For context, recent high profile reentries include the UARS satellite (6.5 tons, in 2011), and the massive Long March-5B booster that launched the core module for China’s Tiangong Space Station in late 2022 (weighing in at 23 tons).

ERS-2 in the clean room on Earth prior to launch. ESA

ESA passed its first space debris mitigation policy in 2008, 13 years after ERS-2 was launched. In 2011, ESA decided to passively reenter the satellite, and began a series of 66 deorbiting maneuvers to bring its orbit down from 785 kilometers to 573 kilometers. Its fuel drained and batteries exhausted, ERS-2 is now succumbing to the increased drag of the Earth’s atmosphere as we near the peak of the current solar cycle.

Flooding in Prague, seen by ERS-2. ESA Tracking the Reentry

Tracking the satellite is as simple as knowing where and when to look. The ID number for ERS-2 is 1995-021A/23560. ESA has a site set up dedicated to tracking the decay of ERS-2. Aerospace.Org, Space-Track and Heavens-Above are other good sites to follow the end of ERS-2.

Expect the satellite to be a real ‘fast mover’ on its final passes. We saw UARS on its final orbit, flashing as it tumbled swiftly across the sky.

Taking out ERS-2 highlights the growing dilemma posed by space junk. There are currently over 25,800 objects in Earth orbit. That amount is growing exponentially as the annual launch cadence increases. 2023 saw a record 212 launches reach orbit, and 2024 is on track to break that number. The rise of mega-constellations such as SpaceX’s Starlink is adding to this burden.

The Age of Space Debris

Space junk adds to the number of artificial ‘stars’ seen whizzing across the night sky, impacts astronomical sky surveys, and poses a hazard to crewed missions and the International Space Station and the Tiangong Space Station. Reentries also contaminate the atmosphere, and a recent study suggests that mega-constellations may even impact the Earth’s magnet field. And while it’s mainly wealthier countries in the northern hemisphere that are launching satellites, the global south disproportionately bears the brunt of uncontrolled reentries.

Finally, all of these are consequences we don’t fully understand and are worthy of further study. For now, you can still track the demise of ERS-2, as it comes to a fiery end this week.

The post European Satellite ERS-2 to Reenter Earth’s Atmosphere This Week appeared first on Universe Today.

Categories: Astronomy

Star Trek's Seven of Nine returns in new novel 'Picard: Firewall' (exclusive)

Space.com - Mon, 02/19/2024 - 12:00pm
Space.com has an exclusive excerpt from New York Times bestselling author David Mack's "Picard: Firewall," a new Star Trek novel featuring former Borg drone Seven of Nine.
Categories: Astronomy

Monster black hole powers the brightest known object in the universe

New Scientist Space - Space Headlines - Mon, 02/19/2024 - 11:00am
Astronomers have found a quasar 12 billion light years away hosting a supermassive black hole that gobbles up a sun-sized amount of mass every day
Categories: Astronomy

Monster black hole powers the brightest known object in the universe

New Scientist Space - Cosmology - Mon, 02/19/2024 - 11:00am
Astronomers have found a quasar 12 billion light years away hosting a supermassive black hole that gobbles up a sun-sized amount of mass every day
Categories: Astronomy

Niacin supplements linked to greater risk of heart attacks and strokes

New Scientist Space - Space Headlines - Mon, 02/19/2024 - 11:00am
People with higher levels of niacin in their blood may be more at risk of a heart attack or stroke, possibly because too much of the vitamin inflames blood vessels
Categories: Astronomy

Niacin supplements linked to greater risk of heart attacks and strokes

New Scientist Space - Cosmology - Mon, 02/19/2024 - 11:00am
People with higher levels of niacin in their blood may be more at risk of a heart attack or stroke, possibly because too much of the vitamin inflames blood vessels
Categories: Astronomy

Brightest quasar ever seen is powered by black hole that eats a 'sun a day'

Space.com - Mon, 02/19/2024 - 11:00am
Astronomers have discovered a quasar that remained hidden for over the years is the brightest ever, powered by the fastest growing black hole ever discovered that eats a sun every day.
Categories: Astronomy

New evidence finally reveals how male and female brains really differ

New Scientist Space - Space Headlines - Mon, 02/19/2024 - 10:58am
Research is cutting through historical discrimination and gender politics to get to the truth about differences between the brains of men and women
Categories: Astronomy

New evidence finally reveals how male and female brains really differ

New Scientist Space - Cosmology - Mon, 02/19/2024 - 10:58am
Research is cutting through historical discrimination and gender politics to get to the truth about differences between the brains of men and women
Categories: Astronomy

Underwater photo competition showcases stunning images of marine life

New Scientist Space - Space Headlines - Mon, 02/19/2024 - 10:41am
Diving seabirds, a tiny octopus and a close encounter with a grey whale feature in breathtaking entries for the 2024 Underwater Photographer of the Year competition
Categories: Astronomy

Underwater photo competition showcases stunning images of marine life

New Scientist Space - Cosmology - Mon, 02/19/2024 - 10:41am
Diving seabirds, a tiny octopus and a close encounter with a grey whale feature in breathtaking entries for the 2024 Underwater Photographer of the Year competition
Categories: Astronomy

Build your own moon base and explore the lunar surface in 'Moonshot' (video)

Space.com - Mon, 02/19/2024 - 10:00am
The new lunar simulation video game "Moonshot" offers players the chance to build and manage their own settlements on the moon's surface.
Categories: Astronomy

NASA's twin spacecraft will go to the ends of the Earth to combat climate change

Space.com - Mon, 02/19/2024 - 9:00am
In Spring 2024, NASA will launch two tiny twin satellites as part of the PREFIRE mission that will journey to the poles to collect data that will help monitor climate change.
Categories: Astronomy

The strange truth about why thinking hard makes you feel exhausted

New Scientist Space - Cosmology - Mon, 02/19/2024 - 9:00am
Your brain burns through the same amount of energy whether you’re daydreaming or taking an exam. So why do we experience mental fatigue?
Categories: Astronomy

The strange truth about why thinking hard makes you feel exhausted

New Scientist Space - Space Headlines - Mon, 02/19/2024 - 9:00am
Your brain burns through the same amount of energy whether you’re daydreaming or taking an exam. So why do we experience mental fatigue?
Categories: Astronomy

Varda's 1st in-space manufacturing capsule to land in Utah this week

Space.com - Mon, 02/19/2024 - 8:00am
Varda Space Industries' first off-Earth manufacturing effort, a mission called W-1, is scheduled to land in northern Utah on Wednesday (Feb. 21).
Categories: Astronomy

New Linguistics Technique Could Reveal Who Spoke the First Indo-European Languages

Scientific American.com - Mon, 02/19/2024 - 8:00am

Linguists and archaeologists have argued for decades about where and when the first Indo-European languages were spoken and what kind of lives those first speakers led

Categories: Astronomy

Against Medical Advice: Another Deadly Consequence of Our Opioid Epidemic

Scientific American.com - Mon, 02/19/2024 - 7:00am

People struggling with addiction cite untreated withdrawal, pain, discrimination and stringent policies as reasons for leaving hospitals against medical advice. We need to take their complaints seriously

Categories: Astronomy

Look at How Much the Sun Has Changed in Just Two Years

Universe Today - Mon, 02/19/2024 - 6:18am

The solar cycle has been reasonably well understood since 1843 when Samuel Schwabe spent 17 years observing the variation of sunspots. Since then, we have regularly observed the ebb and flow of the sunspots cycle every 11 years. More recently ESA’s Solar Orbiter has taken regular images of the Sun to track the progress as we head towards the peak of the current solar cycle. Two recently released images from February 2021 and October 2023 show how things are really picking up as we head toward solar maximum.

The Sun is a great big ball of plasma, electrically charged gas, which has the amazing property that it can move a magnetic field that may be embedded within.  As the Sun rotates, the magnetic field gets dragged around with it but, because the Sun rotates faster at the equator than at the poles, the field lines get wound up tighter and tighter.

Under this immense stressing, the field lines occasionally break, snap or burst through the surface of the Sun and when they do, we see a sunspot. These dark patches on the visible surface of the Sun are regions where denser concentrations of solar material prohibit heat flow to the visible surface giving rise to slightly cooler, and therefore darker patches on the Sun. 

A collage of new solar images captured by the Inouye Solar Telescope, which is a small amount of solar data obtained during the Inouye’s first year of operations throughout its commissioning phase. Images include sunspots and quiet regions of the Sun, known as convection cells. (Credit: NSF/AURA/NSO)

The slow rotation of the Sun and the slow but continuous winding up of the field lines means that sun spots become more and more numerous as the field gets more distorted. Observed over a period of years the spots seem to slowly migrate from the polar regions to the equatorial regions as the solar cycle progresses. 

To try and help understand this complex cycle and unlock other mysteries of the Sun, the European Space Agency launched its Solar Orbiter on 10 February 2020. Its mission to explore the Sun’s polar regions, understand what drives the 11 year solar cycle and what drives the heating of the corona, the outer layers of the Sun’s atmosphere. 

Solar Orbiter

Images from Solar Orbiter have been released that show closeups of the Sun’s visible surface, the photosphere as it nears peak of solar activity. At the beginning of the cycle, at solar minimum in 2019, there was relatively little activity and only a few sunspots. Since then, things have been slowly increasing. The image from February 2021 showed a reasonably quiet Sun but an image taken in October last year shows that things are, dare I say, hotting up! The maximum of this cycle is expected to occur in 2025 which supports theories that the period of maximum activity could arrive a year earlier. 

Understanding the cycle is not just of whimsical scientific interest, it is vital to ensure we minimise damage to ground based and orbiting systems but crucially understand impact on life on Earth. 

Source : Sun’s surprising activity surge in Solar Orbiter snapshot

The post Look at How Much the Sun Has Changed in Just Two Years appeared first on Universe Today.

Categories: Astronomy

Big, doomed satellite seen from space as it tumbles towards a fiery reentry on Feb. 21 (photos)

Space.com - Mon, 02/19/2024 - 6:00am
Non-Earth imaging company HEO Robotics captured breathtaking images of ESA's ERS-2 satellite as it tumbles towards an atmospheric reentry on Feb. 21.
Categories: Astronomy